meson error

# Conflicts:
#	include/builtins.h
#	include/data.h
#	include/editor_op.h
#	include/file_io.h
#	include/input.h
#	include/row_op.h
#	install.sh
#	main.c
#	meson.build
#	src/builtins.c
#	src/editor_op.c
#	src/file_io.c
#	src/init.c
#	src/input.c
#	src/output.c
#	src/row_op.c

assets/beluga.txt

@@ -1,43 +1,43 @@
                       **#%#*****###%**
-                *##+--------------------=##*  
-             #*=----------------------------=*#*                                 
-          #*------------------------------------*#                               
-        %+----------------------------------------=#*                            
-       #+---------------------------------------------##                            
-     *#-------------------------------------------------=##                         
+                *##+--------------------=##*
+             #*=----------------------------=*#*
+          #*------------------------------------*#
+        %+----------------------------------------=#*
+       #+---------------------------------------------##
+     *#-------------------------------------------------=##
     *#----------------------------------------------------:-##
-    #----------------------------------------------------------##                   
-   #=--------------------------------------------------------------##                
-  +--------------------------+@#-%*-----------------------------------#*         
-  +--------------------------%@@@@#-------------------------------------**                              BELUGA - VERSION 2.3
+    #----------------------------------------------------------##
+   #=--------------------------------------------------------------##
+  +--------------------------+@#-%*-----------------------------------#*
+  +--------------------------%@@@@#-------------------------------------**                              BELUGA - VERSION 2.4
   *-=-------------------------#@@*---------------------------------------=%
   %*#==--------------------------------------------------------------------+#                           ----- KEY-BINDS -----
   *%%=-=--------------------------------------------------------------------=#                          CTRL-x CTRL-c  leave
   %=--------------------------------------------------------------------------#*                        CTRL-x CTRL-s   save
  %-----------------------------------------------------------------------------**                       CTRL-x f   open-file
-*+--=---===----=---------------=*-----------------------------------------------** 
- #--=##      *#%#*+==----==+**+----------------------=  ***=---------------------% 
- *%**=-----------====    ==---------------------------------=+#+-----------------=#                                 
-   *%=----------------------------------------------------------=#*---------------#                                 
-     ##=----------------------------------=------------------------+%=------------+#                                
-       #%+---------------------------------=*------------------------+%------------#                                
-         *#%*=-------------=-----------------#-------------------------#+----------#                                
-             **#%#*******+=======-------------#=------------------------#----------#                                
-                #===#*=======------------------#*----=-----------=--=##*-----------#                                
-                 -====##=------------------------*%+------------=*#+=====----------#                                
-                 --=====+#*=----------------------=-=+*#####***+=======-----------=*                                
-                %------=====*%*=-------------------------========-----------------+*                                
-                 *-=--------====%%###+=--------------------------=-----------------#                                
-                  #-----------=%        +*##%%%%%%@@%%%%####*==---------------------**                              
-                    %=-------#*                                  #%*=-----------------+#                              
-                     *%+--=##                                       ##=-----------------=#*                           
-                        **                                       #+----=-------------------#*                       
-                                                               %+----------------------------#*                     
-                                                             *%-------------==----------------+#                    
-                                                            ##--------------==------------------#                     
-                                                           *#--------------===%-----------------=%                  
-                                                          ##---------------=-##*-----------------+#                 
-                                                        *#---------------==#+=#%-----------------%                 
-                                                       *%---------------+#      %*---------------#*                  
-                                                      *#------------=+#*          #%*=-----------#*                  
-                                                       #****##******                 *#%%##+=----%                 
+*+--=---===----=---------------=*-----------------------------------------------**
+ #--=##      *#%#*+==----==+**+----------------------=  ***=---------------------%
+ *%**=-----------====    ==---------------------------------=+#+-----------------=#
+   *%=----------------------------------------------------------=#*---------------#
+     ##=----------------------------------=------------------------+%=------------+#
+       #%+---------------------------------=*------------------------+%------------#
+         *#%*=-------------=-----------------#-------------------------#+----------#
+             **#%#*******+=======-------------#=------------------------#----------#
+                #===#*=======------------------#*----=-----------=--=##*-----------#
+                 -====##=------------------------*%+------------=*#+=====----------#
+                 --=====+#*=----------------------=-=+*#####***+=======-----------=*
+                %------=====*%*=-------------------------========-----------------+*
+                 *-=--------====%%###+=--------------------------=-----------------#
+                  #-----------=%        +*##%%%%%%@@%%%%####*==---------------------**
+                    %=-------#*                                  #%*=-----------------+#
+                     *%+--=##                                       ##=-----------------=#*
+                        **                                       #+----=-------------------#*
+                                                               %+----------------------------#*
+                                                             *%-------------==----------------+#
+                                                            ##--------------==------------------#
+                                                           *#--------------===%-----------------=%
+                                                          ##---------------=-##*-----------------+#
+                                                        *#---------------==#+=#%-----------------%
+                                                       *%---------------+#      %*---------------#*
+                                                      *#------------=+#*          #%*=-----------#*
+                                                       #****##******                 *#%%##+=----%

config/init.lisp

@@ -48,8 +48,8 @@
     ))
                                      ))
 
-(define enter-and-tab 
-  (lambda () 
+(define enter-and-tab
+  (lambda ()
     (editor-insert-new-line)
     (let ((is-in (move-cursor "up")))
       (do ((ch (editor-read-char) (editor-read-char)))
@@ -80,10 +80,13 @@
 (map-key "PAGE-DOWN" move-cursor-page-down "no-prefix")
 (map-key "f" editor-open-file "user")
 (map-key "TAB" editor-insert-tab "no-prefix")
-(map-key "CTRL-k" editor-del-row "no-prefix")
 (map-key "CTRL-s" buffer-find "no-prefix")
-(map-key "CTRL-r" editor-move-to-end-of-word "no-prefix")
+(map-key "CTRL-r" buffer-find-reverse "no-prefix")
+(map-key "ARROW-RIGHT" editor-switch-next-buffer "user")
 (map-key "\"" editor-split-screen-vertical "user")
 (map-key "o" editor-switch-next-pane "user")
 (map-key "*" editor-unify-panes "user")
-
+(map-key "CTRL-y" editor-paste "no-prefix")
+(map-key "CTRL-k" editor-cut-end-line "no-prefix")
+(map-key "a" editor-move-cursor-beg-buffer "user")
+(map-key "z" editor-move-cursor-end-buffer "user")

include/buffer.h

@@ -13,7 +13,7 @@
  * @param filename Path to the file
  * @return Buffer ID on success, -1 on failure
  */
-int bufferCreate(const char *filename);
+int bufferCreate(const char *filename, enum bufferStatus_e state);
 
 /**
  * @brief Switches to a specific buffer by ID
@@ -55,4 +55,15 @@ int bufferSave(void);
  */
 int bufferSaveAll(void);
 
+void bufferFind(struct buffer_t *buf);
+void bufferFindReverse(struct buffer_t* buf);
+void bufferInsertNewLine();
+void bufferInsertBytes(const char *src, int n);
+void bufferDelBytes();
+void bufferRowInsertBytes(struct buffer_t *buffer, row_t *row, int at, const char *src, int n);
+void bufferRowDelByte(struct buffer_t *buffer, row_t *row, int at, int n);
+void bufferInsertRow(struct buffer_t *buffer, int at, char *s, size_t len);
+void bufferFreeRow(row_t *row);
+
+
 #endif

include/builtins.h

@@ -17,7 +17,6 @@ Lisp l_editorInsertNewLine(Lisp args, LispError* e, LispContext ctx);
 Lisp l_editorInserTab(Lisp args, LispError *e, LispContext ctx);
 Lisp deletePreviousChar(Lisp args, LispError *e, LispContext ctx);
 Lisp editorPrintC(Lisp args, LispError *e, LispContext ctx);
-Lisp editorDelRow_L(Lisp args, LispError *e, LispContext ctx);
 Lisp editorReadChar_L(Lisp args, LispError *e, LispContext ctx);
 
 // Editor
@@ -36,6 +35,7 @@ Lisp addPackage(Lisp args, LispError *e, LispContext ctx);
 
 Lisp editorSwitchNextBuffer(Lisp args, LispError *e, LispContext ctx);
 Lisp bufferFind_L(Lisp args, LispError *e, LispContext ctx);
+Lisp bufferFindReverse_L(Lisp args, LispError *e, LispContext ctx);
 
 
 // Pane
@@ -45,12 +45,16 @@ Lisp editorSwitchNextPane(Lisp args, LispError *e, LispContext ctx);
 Lisp editorUnifiedPanes(Lisp args, LispError *e, LispContext ctx);
 
 
+Lisp editorPaste(Lisp args, LispError *e, LispContext ctx);
+Lisp editorCutEndLine(Lisp args, LispError *e, LispContext ctx);
 
-
-
+Lisp editorMoveBegBuffer(Lisp args, LispError *e, LispContext ctx);
+Lisp editorMoveEndBuffer(Lisp args, LispError *e, LispContext ctx);
 
 // Other
 
+
+
 void free_structs(void);
 
 #endif

include/data.h

@@ -8,18 +8,23 @@
 #include "lisp.h"
 
 /**
- * \struct erow
+ * \struct row_t
  * \brief Store one editor row
  * \param
  * */
 
-typedef struct frow {
+typedef struct row {
   int size;     /**< Size of the line */
-  int rsize;    /**< Size of the render line */
+  int cap;    /**< Size of the render line */
   char *chars;  /**< Characters of the line */
-  char *render; /**< The actual line we will print */
-} frow;
+} row_t;
 
+typedef struct context_buffer_t
+{
+  int editor_x, editor_y;
+  int width, height;
+  row_t *rows;
+} ContextBuffer;
 
 /**
  * @brief Split modes for screen layout
@@ -35,15 +40,12 @@ typedef enum {
  */
 typedef struct {
     int buffer_id;        // Which buffer this pane displays
-    int start_row;        // Starting row on screen
-    int start_col;        // Starting column on screen
     int height;           // Height of this pane
     int width;            // Width of this pane
+    int origin_x, origin_y;
     int cursor_x;         // Local cursor x in this pane
     int cursor_y;         // Local cursor y in this pane
-  int rx, ry; 
-    int row_offset;       // Scroll offset for rows
-    int col_offset;       // Scroll offset for columns
+    int x_offset, y_offset;
     int is_active;        // Is this pane currently active
 } EditorPane;
 
@@ -97,15 +99,12 @@ enum buffer_type { FILE_BUFF, TERMINAL_BUFF };
 struct buffer_t {
   enum buffer_type type;
   int buffer_id;
-  int width, height;
-  int x, y; /**< Position in the buffer (cursor) */
-  frow *row;
+  int x, y; /**< Position in the file */
+  row_t *row;
   int numrows;
   char *filename;
   enum bufferStatus_e state;
   int dirty;             /**< Has this buffer been modified since last save */
-  int row_offset;        /**< Scroll offset for rows in this buffer */
-  int col_offset;        /**< Scroll offset for columns in this buffer */
 };
 
 /**
@@ -113,14 +112,19 @@ struct buffer_t {
  * \brief Containing our editor state.
  */
 struct editorConfig {
+  int cursor_x, cursor_y; /**< Cursor position */
   int screenrows;         /**< Terminal height*/
   int screencols;         /**< Terminal width*/
 
   ScreenLayout layout;
-  
+
+  row_t *rows;        /**< Store all the rows printed */
+
+  ContextBuffer* context_buffers;
+
   int dirty;
-  int prefix_state;
-  char status_msg[80];
+
+  char *status_msg;
   time_t status_msg_time;
   struct termios orig_termios; /**< Terminal communication interface */
 
@@ -139,6 +143,7 @@ struct editorConfig {
 
   struct prefix_t *prefix;
   int number_of_prefix;
+  int prefix_state;
 
   struct buffer_t buffers[64];
   int number_of_buffer;
@@ -158,4 +163,5 @@ struct abuf {
 
 extern struct editorConfig E;
 
+
 #endif

include/define.h

@@ -2,28 +2,41 @@
 #define DEFINE_H_
 
 #define CTRL_KEY(k) ((k) & 0x1f)
+#define ALT(k) ((k) | 0x200)  // set bit 9 to mark as Option combo
+
 
 #define ESCAPE '\x1b'
 #define CURSOR_TOP_LEFT "\x1b[H"
 #define HIDE_CURSOR "\x1b[?25l"
 #define SHOW_CURSOR "\x1b[?25h"
 #define ERASE_END_LINE "\x1b[K"
+#define TAB "\t"
+#define SPACE "\x20"
+#define APP_DEBUG
 
-enum editorKey {
-  BACKSPACE = 127,
-  ARROW_LEFT = 1000,
-  ARROW_RIGHT,
-  ARROW_UP,
-  ARROW_DOWN,
-  DEL_KEY,
-  BEG_LINE,
-  END_LINE,
-  PAGE_UP,
-  PAGE_DOWN,
-};
+enum editorKey_e {
+    BACKSPACE = 127,
+    ARROW_LEFT = 1000,
+    ARROW_RIGHT,
+    ARROW_UP,
+    ARROW_DOWN,
+    DEL_KEY,
+    BEG_LINE,
+    END_LINE,
+    PAGE_UP,
+    PAGE_DOWN,
+  };
 
 #define ABUF_INIT {NULL, 0}
 
-#define BELUGA_VERSION "1.1"
+#define BELUGA_VERSION "2.4"
+
+#ifdef __APPLE__
+#define CLIPBOARD_COPY_CMD  "pbcopy"
+#define CLIPBOARD_PASTE_CMD "pbpaste"
+#else
+#define CLIPBOARD_COPY_CMD  "xclip -selection clipboard"
+#define CLIPBOARD_PASTE_CMD "xclip -selection clipboard -o"
+#endif
 
 #endif // DEFINE_H_

include/editor_op.h

@@ -2,12 +2,12 @@
 #define EDITOR_OP_H_
 
 #include "data.h"
-void bufferInsertChar(int c);
-
-void bufferInsertNewLine();
-
-void bufferDelChar();
 
 void editorSetStatusMessage(const char *fmt, ...);
+int editorRowCharCount(row_t *row, int x);
+int editorRowCxToByte(const row_t *row, int cursor_x);
+char *editorGetClipboard(void);
+void editorSetClipboard(const char *text, int len);
+
 
 #endif // EDITOR_OP_H_

include/file_io.h

@@ -2,21 +2,14 @@
 #define FILE_IO_H_
 
 #include "data.h"
-#include "row_op.h"
-#include "terminal.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/types.h>
 
-char *bufferRowsToString(struct buffer_t *buf,int *buffer_len);
-
-
 void editorCloseFile(void);
 
 void editorOpen(struct buffer_t *buffer);
 
 void editorSave();
 
-void bufferFind(struct buffer_t *buf);
-
 #endif // FILE_IO_H_

include/input.h

@@ -22,7 +22,7 @@
 
 char *editorPrompt(char *prompt, char * PlaceHolder, char bPathMode);
 
-char *key_to_string(int key);
+const char *fileCompletion(const char *path);
 
 int editorMoveCursor(int key);
 

include/output.h

@@ -9,8 +9,6 @@
  * \brief Draws left rows of the editor.
  */
 
-void editorDrawRows(struct abuf *ab);
-
 void editorRefreshScreen();
 
 void editorScroll();

include/row_op.h

@@ -8,22 +8,8 @@
 #include <time.h>
 #include <unistd.h>
 
-int bufferRowCxToRx(frow *row, int cursor_x);
 
-int bufferRowRxToCx(frow *row, int rx);
 
-void bufferUpdatfrow(frow *row);
 
-void bufferInsertRow(struct buffer_t *buffer, int at, char *s, size_t len);
-
-void bufferFrefrow(frow *row);
-
-void bufferDelRow(struct buffer_t *buffer, int at);
-
-void bufferRowInsertChar(struct buffer_t *buffer, frow *row, int at, int c);
-
-void bufferRowAppendString(struct buffer_t *buffer, frow *row, char *s, size_t len);
-
-void bufferRowDelchar(struct buffer_t *buffer, frow *row, int at);
 
 #endif // ROW_OP_H_

include/syntax_highlighter.h

@@ -1,7 +1,6 @@
 #ifndef SYNTAX_HIGHLIGHTER_H_
 #define SYNTAX_HIGHLIGHTER_H_
 
-#include "color.h"
 
 // Color codes that only affect foreground, preserving your background color
 #define COLOR_RESET         "\x1b[39m"            // Reset all (4 bytes)
@@ -20,4 +19,3 @@ typedef enum {
 char *highlight_line(const char * line, int *length);
 
 #endif
-

include/terminal.h

@@ -4,8 +4,6 @@
 
 /* includes */
 
-#include "data.h"
-#include "define.h"
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -31,4 +29,8 @@ int getCursorPosition(int *rows, int *cols);
 
 int getWindowSize(int *rows, int *cols);
 
+char *keyToString(int key);
+
+void appDebug(const char *fmt, ...);
+
 #endif

include/utf8.h

@@ -0,0 +1,16 @@
+//
+// Created by Giorgio on 01/05/2026.
+//
+
+#ifndef BELUGA_UTF8_H
+#define BELUGA_UTF8_H
+#include <stdint.h>
+
+uint32_t readUtf8Char(void);
+int utf8Encode(uint32_t cp, char *buf);
+int utf8Seqlen(unsigned char c);
+int codepointWidth(uint32_t codepoint);
+uint32_t utf8Decode(const char** s);
+
+
+#endif //BELUGA_UTF8_H

main.c

@@ -5,19 +5,16 @@
  * interactions. \version 0.1 \date 21 septembre 2024
  */
 
-#include "include/buffer.h"
-#include "include/split_screen.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
 #define _DEFAULT_SOURCE
 #define _BSD_SOURCE
 #define _GNU_SOURCE
 
+#include "include/buffer.h"
+#include "include/split_screen.h"
+#include <string.h>
+#include <unistd.h>
+
 #include "include/data.h"
-#include "include/file_io.h"
 #include "include/init.h"
 #include "include/input.h"
 #include "include/editor_op.h"
@@ -28,20 +25,21 @@ struct editorConfig E;
 int main(int argc, char *argv[]) {
 
   char * splash_screen = (char *) calloc(256, sizeof(char));
-  
+
   enableRawMode();
   initEditor();
   if (argc >= 2) {
     EditorPane *active = splitScreenGetActivePane();
-    active->buffer_id = bufferCreate(argv[1]);
+    active->buffer_id = bufferCreate(argv[1], READ_AND_WRITE);
   } else {
     strcat(splash_screen, getenv("HOME"));
     strcat(splash_screen, "/.beluga/assets/beluga.txt");
-    fprintf(stderr, "%s\n", splash_screen);
+
+    appDebug("splash : %s\n", splash_screen);
     EditorPane *active = splitScreenGetActivePane();
-    active->buffer_id = bufferCreate(splash_screen);
+    active->buffer_id = bufferCreate(splash_screen, READ_ONLY);
   }
-  //free(splash_screen);
+  free(splash_screen);
 
   editorSetStatusMessage("HELP: Ctrl-x Ctrl-s = save | Ctrl-x Ctrl-c = quit");
 

meson.build

@@ -22,11 +22,14 @@ src_files = files(
   'src/terminal.c',
   'src/builtins.c',
   'src/buffer.c',
-  'src/split_screen.c'
+  'src/split_screen.c',
+  'src/utf8.c'
 )
 
 # Executable
 executable('beluga',
   src_files,
   dependencies: [m]
+)
+  dependencies: [m]
 )

src/append_buffer.c

@@ -1,7 +1,5 @@
 #include "../include/append_buffer.h"
 
-extern struct editorConfig E;
-
 void abAppend(struct abuf *ab, const char *s, int len) {
   char *new = realloc(ab->b, ab->len + len);
 

src/buffer.c

@@ -11,18 +11,23 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
+
+#include "include/input.h"
 
-extern struct editorConfig E;
 
 /**
  * @brief Finds a buffer by filename
  * @param filename The filename to search for
  * @return Buffer ID if found, -1 if not found
  */
-static int bufferFindByFilename(const char *filename) {
-    for (int i = 0; i < E.number_of_buffer; i++) {
-        if (E.buffers[i].filename != NULL && 
-            strcmp(E.buffers[i].filename, filename) == 0) {
+static int bufferFindByFilename(const char* filename)
+{
+    for (int i = 0; i < E.number_of_buffer; i++)
+    {
+        if (E.buffers[i].filename != NULL &&
+            strcmp(E.buffers[i].filename, filename) == 0)
+        {
             return E.buffers[i].buffer_id;
         }
     }
@@ -34,9 +39,12 @@ static int bufferFindByFilename(const char *filename) {
  * @param buffer_id The buffer ID to find
  * @return Pointer to buffer, NULL if not found
  */
-struct buffer_t *bufferFindById(int buffer_id) {
-    for (int i = 0; i < E.number_of_buffer; i++) {
-        if (E.buffers[i].buffer_id == buffer_id) {
+struct buffer_t* bufferFindById(int buffer_id)
+{
+    for (int i = 0; i < E.number_of_buffer; i++)
+    {
+        if (E.buffers[i].buffer_id == buffer_id)
+        {
             return &E.buffers[i];
         }
     }
@@ -50,36 +58,37 @@ struct buffer_t *bufferFindById(int buffer_id) {
  * @param filename Path to the file
  * @return Buffer ID on success, -1 on failure
  */
-int bufferCreate(const char *filename) {
+int bufferCreate(const char* filename, enum bufferStatus_e state)
+{
     // Check if file is already open
-    int existing_id = bufferFindByFilename(filename);
-    if (existing_id != -1) {
+    const int existing_id = bufferFindByFilename(filename);
+    if (existing_id != -1)
+    {
         return bufferSwitch(existing_id);
     }
-    
+
     // Check if we have space for more buffers
-    if (E.number_of_buffer >= 64) {
+    if (E.number_of_buffer >= 64)
+    {
         editorSetStatusMessage("Error: maximum buffers reached (64)");
         return -1;
     }
-    
+
     // Initialize new buffer
-    struct buffer_t *new_buf = &E.buffers[E.number_of_buffer];
+    struct buffer_t* new_buf = &E.buffers[E.number_of_buffer];
     new_buf->buffer_id = E.number_of_buffer;
     new_buf->filename = strdup(filename);
     new_buf->type = FILE_BUFF;
-    new_buf->state = READ_AND_WRITE;
+    new_buf->state = state;
     new_buf->x = 0;
     new_buf->y = 0;
-    new_buf->row_offset = 0;
-    new_buf->col_offset = 0;
-    new_buf->dirty = 0;  // New file starts clean
-    
+    new_buf->dirty = 0; // New file starts clean
+
     // Load file content using existing editorOpen
     editorOpen(new_buf);
-    
+
     E.number_of_buffer++;
-    
+
     editorSetStatusMessage("Opened: %s (buffer %d)", filename, new_buf->buffer_id);
     return new_buf->buffer_id;
 }
@@ -90,17 +99,19 @@ int bufferCreate(const char *filename) {
  * @param buffer_id The buffer ID to switch to
  * @return 0 on success, -1 on failure
  */
-int bufferSwitch(int buffer_id) {
-    struct buffer_t *target = bufferFindById(buffer_id);
-    if (target == NULL) {
-      E.layout.panes[E.layout.active_pane].buffer_id = buffer_id;
+int bufferSwitch(int buffer_id)
+{
+    struct buffer_t* target = bufferFindById(buffer_id);
+    if (target == NULL)
+    {
+        E.layout.panes[E.layout.active_pane].buffer_id = buffer_id;
         editorSetStatusMessage("Error: buffer not found");
         return -1;
     }
-        
-    
-    editorSetStatusMessage("Switched to: %s (buffer %d)", 
-                          target->filename, buffer_id);
+
+
+    editorSetStatusMessage("Switched to: %s (buffer %d)",
+                           target->filename, buffer_id);
     return 0;
 }
 
@@ -112,51 +123,62 @@ int bufferSwitch(int buffer_id) {
  * @param buffer_id The buffer ID to close
  * @return 0 on success, -1 on failure
  */
-int bufferClose(int buffer_id) {
-    struct buffer_t *buf = bufferFindById(buffer_id);
-    if (buf == NULL) {
+int bufferClose(int buffer_id)
+{
+    struct buffer_t* buf = bufferFindById(buffer_id);
+    if (buf == NULL)
+    {
         editorSetStatusMessage("Error: buffer not found");
         return -1;
     }
 
-    EditorPane * active = splitScreenGetActivePane();
-    
+    EditorPane* active = splitScreenGetActivePane();
+
     // If this is the current buffer, find next buffer to switch to
-    if (active->buffer_id == buffer_id) {
+    if (active->buffer_id == buffer_id)
+    {
         int next_id = -1;
-        
+
         // Try to switch to next buffer
-        for (int i = 0; i < E.number_of_buffer; i++) {
-            if (E.buffers[i].buffer_id != buffer_id) {
+        for (int i = 0; i < E.number_of_buffer; i++)
+        {
+            if (E.buffers[i].buffer_id != buffer_id)
+            {
                 next_id = E.buffers[i].buffer_id;
                 break;
             }
         }
-        
-        if (next_id != -1) {
+
+        if (next_id != -1)
+        {
             bufferSwitch(next_id);
-        } else {
+        }
+        else
+        {
             // No other buffers, clear editor
             editorCloseFile();
         }
     }
-    
+
     // Free buffer resources
     free(buf->filename);
     buf->filename = NULL;
     buf->buffer_id = -1;
-    
+
     // Remove from buffer list by shifting
-    for (int i = 0; i < E.number_of_buffer; i++) {
-        if (E.buffers[i].buffer_id == buffer_id) {
-            for (int j = i; j < E.number_of_buffer - 1; j++) {
+    for (int i = 0; i < E.number_of_buffer; i++)
+    {
+        if (E.buffers[i].buffer_id == buffer_id)
+        {
+            for (int j = i; j < E.number_of_buffer - 1; j++)
+            {
                 E.buffers[j] = E.buffers[j + 1];
             }
             E.number_of_buffer--;
             break;
         }
     }
-    
+
     editorSetStatusMessage("Closed buffer %d", buffer_id);
     return 0;
 }
@@ -165,8 +187,9 @@ int bufferClose(int buffer_id) {
  * @brief Gets the current active buffer
  * @return Pointer to current buffer_t, NULL if none
  */
-struct buffer_t *bufferGetCurrent(void) {
-  EditorPane * active = splitScreenGetActivePane();
+struct buffer_t* bufferGetCurrent(void)
+{
+    EditorPane* active = splitScreenGetActivePane();
     return bufferFindById(active->buffer_id);
 }
 
@@ -175,24 +198,27 @@ struct buffer_t *bufferGetCurrent(void) {
  * @details Prints buffer information to status message
  * @return Number of open buffers
  */
-int bufferListAll(void) {
-    if (E.number_of_buffer == 0) {
+int bufferListAll(void)
+{
+    if (E.number_of_buffer == 0)
+    {
         editorSetStatusMessage("No buffers open");
         return 0;
     }
-    
+
     char buf[256] = "";
     int offset = 0;
-    EditorPane * active = splitScreenGetActivePane();
-    
-    for (int i = 0; i < E.number_of_buffer; i++) {
-        struct buffer_t *b = &E.buffers[i];
+    EditorPane* active = splitScreenGetActivePane();
+
+    for (int i = 0; i < E.number_of_buffer; i++)
+    {
+        struct buffer_t* b = &E.buffers[i];
         char marker = (b->buffer_id == active->buffer_id) ? '*' : ' ';
         offset += snprintf(&buf[offset], sizeof(buf) - offset,
-                          "%c%d:%s ", marker, b->buffer_id, 
-                          b->filename ? b->filename : "[No Name]");
+                           "%c%d:%s ", marker, b->buffer_id,
+                           b->filename ? b->filename : "[No Name]");
     }
-    
+
     editorSetStatusMessage("Buffers: %s", buf);
     return E.number_of_buffer;
 }
@@ -201,13 +227,15 @@ int bufferListAll(void) {
  * @brief Saves current buffer to disk
  * @return 0 on success, -1 on failure
  */
-int bufferSave(void) {
-    EditorPane * active = splitScreenGetActivePane();
-    if (active->buffer_id == -1) {
+int bufferSave(void)
+{
+    EditorPane* active = splitScreenGetActivePane();
+    if (active->buffer_id == -1)
+    {
         editorSetStatusMessage("Error: no buffer active");
         return -1;
     }
-    
+
     editorSave();
     return 0;
 }
@@ -217,20 +245,233 @@ int bufferSave(void) {
  * @details Iterates through all buffers, saves each one
  * @return 0 on success, -1 on failure
  */
-int bufferSaveAll(void) {
+int bufferSaveAll(void)
+{
     int saved = 0;
     int failed = 0;
-    
-    for (int i = 0; i < E.number_of_buffer; i++) {
-        if (bufferSwitch(E.buffers[i].buffer_id) == 0) {
-            if (E.dirty && bufferSave() == 0) {
+
+    for (int i = 0; i < E.number_of_buffer; i++)
+    {
+        if (bufferSwitch(E.buffers[i].buffer_id) == 0)
+        {
+            if (E.dirty && bufferSave() == 0)
+            {
                 saved++;
             }
-        } else {
+        }
+        else
+        {
             failed++;
         }
     }
-    
+
     editorSetStatusMessage("Saved %d buffers (%d failed)", saved, failed);
     return (failed == 0) ? 0 : -1;
 }
+
+/**
+ * @brief Searches for a string in the document
+ * @details Prompts user for a search query, then searches forward from current
+ * cursor position. Updates cursor position to the first match found.
+ * @note Updates global editor state E (cursor position, row_offset)
+ * @note Search is case-sensitive and operates on rendered line content
+ * @note Searches begin from the line after current cursor position
+ * @see editorPrompt()
+ * @see editorRowRxToCx()
+ */
+void bufferFind(struct buffer_t* buf)
+{
+    appDebug("searching\n");
+    char* query = editorPrompt("Search: %s (ESC to cancel)", "", 0);
+
+    if (query == NULL)
+        return;
+    int i;
+    for (i = buf->y+1; i < buf->numrows; i++)
+    {
+        row_t* row = &buf->row[i];
+        char* match = strstr(row->chars, query);
+        if (match)
+        {
+            buf->y = i;
+            break;
+        }
+    }
+    free(query);
+}
+
+void bufferFindReverse(struct buffer_t* buf)
+{
+    appDebug("searching\n");
+    char* query = editorPrompt("Reverse search: %s (ESC to cancel)", "", 0);
+
+    if (query == NULL)
+        return;
+    int i;
+    if (!buf->y)
+        return;
+    for (i = buf->y - 1; i >= 0; i--)
+    {
+        row_t* row = &buf->row[i];
+        char* match = strstr(row->chars, query);
+        if (match)
+        {
+            buf->y = i;
+            break;
+        }
+    }
+    free(query);
+}
+
+void bufferInsertRow(struct buffer_t *buffer, int at, char *s, size_t len) {
+  if (at < 0 || at > buffer->numrows)
+    return;
+
+  row_t *tmp = realloc(buffer->row, sizeof(row_t) * (buffer->numrows + 1));
+  if (!tmp)
+    return;
+  buffer->row = tmp;
+
+  /* Shift existing rows to make room at 'at' — no at++ */
+  if (at < buffer->numrows) {
+    memmove(&buffer->row[at + 1], &buffer->row[at],
+            sizeof(row_t) * (buffer->numrows - at)); /* not -at+1 */
+  }
+
+  buffer->row[at].size  = len;
+  buffer->row[at].cap   = len + 1;
+  buffer->row[at].chars = malloc(len + 1);
+  if (!buffer->row[at].chars)
+    return;
+  memcpy(buffer->row[at].chars, s, len);
+  buffer->row[at].chars[len] = '\0'; /* always NUL-terminate */
+
+  buffer->numrows++;
+  buffer->dirty++;
+}
+
+void bufferFreeRow(row_t *row) { free(row->chars); }
+
+/**
+ * \fn editorRowInsertChar(erow *row, int at, int c)
+ * \param at Index of where we want to insert the char */
+
+void bufferRowInsertBytes(struct buffer_t *buffer, row_t *row, int at,
+                          const char *src, int n) {
+  if (buffer->state == READ_ONLY)
+    return;
+  if (row->size + n + 1 > row->cap) {
+    row->cap = (row->size + n + 1) * 2;
+    row->chars = realloc(row->chars, row->cap);
+  }
+  memmove(row->chars + at + n, row->chars + at, row->size - at);
+  memcpy(row->chars + at, src, n);
+  row->size += n;
+  row->chars = realloc(row->chars, row->size + 2);
+  ++buffer->dirty;
+}
+
+/**
+ * \fn bufferRowDelChar(struct bufferConfig *E, frow *frow, int at)
+ * \brief Delete the a char at the chosen position on the given row
+ * \param at Index of the char to delete
+ * \param row Row on operation is made */
+void bufferRowDelByte(struct buffer_t *buffer, row_t *row, int at, int n) {
+    if (buffer->state == READ_ONLY)
+        return;
+    if (at < 0 || at >= row->size)
+        return;
+  memmove(row->chars + at, row->chars + at + n, row->size - at - n);
+  row->size -= n;
+  row->chars[row->size] = '\0';
+  buffer->x -= n;
+  ++buffer->dirty;
+}
+
+
+void bufferInsertBytes(const char* src, int n)
+{
+    appDebug("bufferInsertBytes \r\n");
+    EditorPane* active = splitScreenGetActivePane();
+    struct buffer_t* buf = bufferFindById(active->buffer_id);
+    if (buf->y == buf->numrows)
+    {
+        bufferInsertRow(buf, buf->numrows, "", 0);
+    }
+    bufferRowInsertBytes(buf, &buf->row[buf->y], buf->x, src, n);
+    buf->x += n;
+}
+
+void bufferDelBytes(void)
+{
+    EditorPane* active = splitScreenGetActivePane();
+    struct buffer_t* buf = bufferFindById(active->buffer_id);
+
+    /* Nothing to delete */
+    if (buf->numrows == 0) return;
+    if (buf->x == 0 && buf->y == 0) return;
+
+    /* Use row_offset, not col_offset, for row indexing */
+    row_t* r = &buf->row[buf->y];
+
+    if (buf->x > 0)
+    {
+        int byte_end = editorRowCxToByte(r, buf->x);
+        int byte_start = editorRowCxToByte(r, buf->x - 1);
+        int char_width = byte_end - byte_start; /* byte width of the character */
+
+        bufferRowDelByte(buf, r, byte_start, char_width);
+        E.dirty = 1;
+    }
+    else
+    {
+        /* Merge current row into the previous one */
+        row_t* prev = &buf->row[buf->y - 1];  // FIX: was buf->y (same as r)
+        int prev_char_count = editorRowCharCount(prev, prev->size);
+
+        bufferRowInsertBytes(buf, prev, prev->size, r->chars, r->size);
+        free(r->chars);
+        r->chars = NULL;
+
+        memmove(&buf->row[buf->y],
+                &buf->row[buf->y + 1],
+                sizeof(row_t) * (buf->numrows - buf->y - 1));
+        buf->numrows--;
+
+        active->cursor_x = prev_char_count;
+        buf->x = prev_char_count;
+        active->cursor_y--;
+        buf->y--;
+        E.dirty = 1;
+    }
+}
+
+void bufferInsertNewLine(void) {
+    appDebug("Inserting new line\n");
+    EditorPane *active = splitScreenGetActivePane();
+    struct buffer_t *buf = bufferFindById(active->buffer_id);
+
+    appDebug("buf x %d\n", buf->x);
+
+    if (buf->y >= buf->numrows) {
+        /* Cursor is past the last row: just append a blank line */
+        bufferInsertRow(buf, buf->numrows, "", 0);
+    } else {
+        row_t *row = &buf->row[buf->y];
+
+        /* Insert the tail (from cursor to end) as a new row below */
+        bufferInsertRow(buf, buf->y + 1, &row->chars[buf->x], row->size - buf->x);
+
+        /* Re-fetch: realloc inside bufferInsertRow may have moved the array */
+        row = &buf->row[buf->y];
+
+        /* Truncate the current row at the cursor */
+        row->size           = buf->x;
+        row->chars[row->size] = '\0';
+        /* Do NOT touch row->cap — the allocation is still valid */
+    }
+
+    buf->y++;
+    buf->x = 0;
+    appDebug("Insert new line done\n");
+}

src/builtins.c

@@ -2,18 +2,20 @@
  * @file builtins.c
  * @brief Built-in Lisp functions for editor operations
  * @details Provides Lisp bindings for core editor functionality including
- * cursor movement, file operations, keybinding management, and text manipulation
+ * cursor movement, file operations, keybinding management, and text
+ * manipulation
  */
 
 #include "../include/builtins.h"
+#include "../include/buffer.h"
 #include "../include/data.h"
 #include "../include/define.h"
 #include "../include/editor_op.h"
 #include "../include/file_io.h"
 #include "../include/input.h"
-#include "../include/row_op.h"
-#include "../include/buffer.h"
+#include "../include/terminal.h"
 #include "../include/split_screen.h"
+#include "../include/completion.h"
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -57,7 +59,7 @@ Lisp mapKey(Lisp args, LispError *e, LispContext ctx) {
   const char *key_sequence = lisp_string(lisp_car(args));
   args = lisp_cdr(args);
   // second argument
-  Lisp func = lisp_car(args);
+  const Lisp func = lisp_car(args);
 
   E.key_binds = (struct keyBind_t *)realloc(
       E.key_binds, ++E.number_of_keybinds * sizeof(struct keyBind_t));
@@ -74,13 +76,14 @@ Lisp mapKey(Lisp args, LispError *e, LispContext ctx) {
   struct prefix_t prefix = find_prefix(prefix_name);
 
   E.key_binds[E.number_of_keybinds - 1].prefix_id = prefix.prefix_id;
-  
+
   return lisp_null();
 }
 
 /**
  * @brief Lisp function to move cursor in a specified direction
- * @details Moves the editor cursor up, down, left, or right based on direction string.
+ * @details Moves the editor cursor up, down, left, or right based on direction
+ * string.
  * @param args Lisp list with one argument: direction string
  *        - "u": up, "d": down, "r": right, "l": left
  * @param e Error pointer for Lisp error handling
@@ -106,7 +109,7 @@ Lisp moveCursor(Lisp args, LispError *e, LispContext ctx) {
     is_in = editorMoveCursor(ARROW_LEFT);
     break;
   }
-  fprintf(stderr, "move lisp %d\n", is_in);
+  appDebug("move lisp %d\n", is_in);
   return lisp_make_bool(is_in);
 }
 
@@ -130,21 +133,20 @@ void free_structs(void) {
   for (i = 0; i < E.number_of_buffer; ++i) {
     free(E.buffers[i].filename);
     for (j = 0; j < E.buffers[i].numrows; ++j) {
-      free(E.buffers[i].row[j].render);
       free(E.buffers[i].row[j].chars);
     }
     free(E.buffers[i].row);
   }
-  
+
   free(E.init_file_path);
   fclose(E.fd_init_file);
-  
 }
 
 /**
  * @brief Lisp function to quit the editor
- * @details Closes editor with unsaved changes protection. Prompts user to confirm
- * quit after multiple attempts if file is dirty. Cleans up resources and restores terminal.
+ * @details Closes editor with unsaved changes protection. Prompts user to
+ * confirm quit after multiple attempts if file is dirty. Cleans up resources
+ * and restores terminal.
  * @param args Lisp arguments (unused)
  * @param e Error pointer for Lisp error handling
  * @param ctx Lisp context
@@ -182,10 +184,10 @@ Lisp editorQuit(Lisp args, LispError *e, LispContext ctx) {
 
 Lisp l_editorSplitScreenVertical(Lisp args, LispError *e, LispContext ctx) {
   if (E.number_of_buffer >= 2) {
-        splitScreenVertical(E.buffers[0].buffer_id, E.buffers[1].buffer_id);
-    } else {
-        editorSetStatusMessage("Need at least 2 buffers open");
-    }
+    splitScreenVertical(E.buffers[0].buffer_id, E.buffers[1].buffer_id);
+  } else {
+    editorSetStatusMessage("Need at least 2 buffers open");
+  }
   return lisp_null();
 }
 
@@ -222,9 +224,8 @@ Lisp l_editorInsertNewLine(Lisp args, LispError *e, LispContext ctx) {
  * @note Uses E.constantes.TAB_LENGTH for indentation width
  */
 Lisp l_editorInserTab(Lisp args, LispError *e, LispContext ctx) {
-
-  for (int i = 0; i<E.constantes.TAB_LENGTH; ++i) {
-    bufferInsertChar(' ');
+  for (int i = 0; i < E.constantes.TAB_LENGTH; ++i) {
+    bufferInsertBytes(" ", 1);
   }
 
   return lisp_null();
@@ -240,7 +241,9 @@ Lisp l_editorInserTab(Lisp args, LispError *e, LispContext ctx) {
  * @note Updates global editor state E
  */
 Lisp moveCursorBeginLine(Lisp args, LispError *e, LispContext ctx) {
-  E.layout.panes[E.layout.active_pane].cursor_x = 0;
+  EditorPane *active = splitScreenGetActivePane();
+  struct buffer_t *buf = bufferFindById(active->buffer_id);
+  buf->x = 0;
   return lisp_null();
 }
 
@@ -256,9 +259,7 @@ Lisp moveCursorBeginLine(Lisp args, LispError *e, LispContext ctx) {
 Lisp moveCursorEndLine(Lisp args, LispError *e, LispContext ctx) {
   EditorPane *active = splitScreenGetActivePane();
   struct buffer_t *buf = bufferFindById(active->buffer_id);
-  if (active->cursor_y < buf->numrows) {
-    active->cursor_x = buf->row[active->cursor_y].size;
-  }
+  buf->x = buf->row[buf->y].size;
   return lisp_null();
 }
 
@@ -272,13 +273,14 @@ Lisp moveCursorEndLine(Lisp args, LispError *e, LispContext ctx) {
  * @see editorDelChar()
  */
 Lisp deletePreviousChar(Lisp args, LispError *e, LispContext ctx) {
-  bufferDelChar();
+  bufferDelBytes();
   return lisp_null();
 }
 
 /**
  * @brief Lisp function to move cursor up by one screen
- * @details Scrolls up one full screen height, moving cursor to top of visible area.
+ * @details Scrolls up one full screen height, moving cursor to top of visible
+ * area.
  * @param args Lisp arguments (unused)
  * @param e Error pointer for Lisp error handling
  * @param ctx Lisp context
@@ -288,7 +290,7 @@ Lisp deletePreviousChar(Lisp args, LispError *e, LispContext ctx) {
  */
 Lisp editorMoveCursorPageUp(Lisp args, LispError *e, LispContext ctx) {
   EditorPane *active = splitScreenGetActivePane();
-  active->cursor_y = active->row_offset;
+  active->cursor_y = active->y_offset;
   int times = E.screenrows;
   while (--times) {
     editorMoveCursor(ARROW_UP);
@@ -298,7 +300,8 @@ Lisp editorMoveCursorPageUp(Lisp args, LispError *e, LispContext ctx) {
 
 /**
  * @brief Lisp function to move cursor down by one screen
- * @details Scrolls down one full screen height, moving cursor to bottom of visible area.
+ * @details Scrolls down one full screen height, moving cursor to bottom of
+ * visible area.
  * @param args Lisp arguments (unused)
  * @param e Error pointer for Lisp error handling
  * @param ctx Lisp context
@@ -309,7 +312,7 @@ Lisp editorMoveCursorPageUp(Lisp args, LispError *e, LispContext ctx) {
 Lisp editorMoveCursorPageDown(Lisp args, LispError *e, LispContext ctx) {
   EditorPane *active = splitScreenGetActivePane();
   struct buffer_t *buffer = bufferFindById(active->buffer_id);
-  active->cursor_y = active->row_offset + E.screenrows - 1;
+  active->cursor_y = active->y_offset + E.screenrows - 1;
   if (active->cursor_y > buffer->numrows) {
     active->cursor_y = buffer->numrows;
   }
@@ -334,20 +337,20 @@ Lisp editorMoveCursorPageDown(Lisp args, LispError *e, LispContext ctx) {
  */
 Lisp editorOpenFile(Lisp args, LispError *e, LispContext ctx) {
   char *filename = editorPrompt("Open : %s", getenv("PWD"), 1);
-  if (filename){
+  if (filename) {
     //    editorOpen(filename);
     EditorPane *active = splitScreenGetActivePane();
-    active->buffer_id = bufferCreate(filename);
+    active->buffer_id = bufferCreate(filename, READ_AND_WRITE);
   }
   free(filename);
-  
 
   return lisp_null();
 }
 
 /**
  * @brief Lisp function to insert a character
- * @details Extracts a character from Lisp string argument and inserts it at cursor.
+ * @details Extracts a character from Lisp string argument and inserts it at
+ * cursor.
  * @param args Lisp list with one string argument
  * @param e Error pointer for Lisp error handling
  * @param ctx Lisp context
@@ -355,8 +358,8 @@ Lisp editorOpenFile(Lisp args, LispError *e, LispContext ctx) {
  * @note Uses first character of the string argument
  */
 Lisp editorPrintC(Lisp args, LispError *e, LispContext ctx) {
-  char c = lisp_string(lisp_car(args))[0];
-  bufferInsertChar(c);
+  const char *src = lisp_string(lisp_car(args));
+  bufferInsertBytes(src, strlen(src));
   return lisp_null();
 }
 
@@ -373,14 +376,14 @@ Lisp editorPrintC(Lisp args, LispError *e, LispContext ctx) {
  */
 Lisp addPackage(Lisp args, LispError *e, LispContext ctx) {
   const char *package_name = lisp_string(lisp_car(args));
-  fprintf(stderr, "%s\n", package_name);
+  appDebug("%s\n", package_name);
   char *package_dir = (char *)calloc(256, sizeof(char));
   FILE *fd_package = NULL;
   strcat(package_dir, getenv("HOME"));
   strcat(package_dir, "/.beluga/packages/");
   strcat(package_dir, package_name);
   strcat(package_dir, "/init.lisp");
-  fprintf(stderr, "%s\n", package_dir);
+  appDebug("%s\n", package_dir);
   fd_package = fopen(package_dir, "r");
   lisp_eval(lisp_read_file(fd_package, &E.ctx_error, E.ctx), &E.ctx_error,
             E.ctx);
@@ -390,30 +393,13 @@ Lisp addPackage(Lisp args, LispError *e, LispContext ctx) {
   return lisp_null();
 }
 
-/**
- * @brief Lisp function to delete the current row
- * @details Removes the line at the current cursor position.
- * @param args Lisp arguments (unused)
- * @param e Error pointer for Lisp error handling
- * @param ctx Lisp context
- * @return lisp_null()
- * @note Updates global editor state E
- * @see editorDelRow()
- */
-Lisp editorDelRow_L(Lisp args, LispError *e, LispContext ctx) {
-  EditorPane *active = splitScreenGetActivePane();
-  struct buffer_t *buffer = bufferFindById(active->buffer_id);
-  bufferDelRow(buffer, active->cursor_y);
-  return lisp_null();
-}
-
 Lisp editorSwitchNextBuffer(Lisp args, LispError *e, LispContext ctx) {
-  fprintf(stderr, "switch buffer\n");
+  appDebug("switch buffer\n");
   if (E.number_of_buffer > 0) {
     EditorPane *active = splitScreenGetActivePane();
     int next_idx = (active->buffer_id + 1) % E.number_of_buffer;
     active->buffer_id = next_idx;
-    }
+  }
 
   return lisp_null();
 }
@@ -440,17 +426,34 @@ Lisp editorUnifiedPanes(Lisp args, LispError *e, LispContext ctx) {
  * @see editorFind()
  */
 Lisp bufferFind_L(Lisp args, LispError *e, LispContext ctx) {
-  fprintf(stderr, "LispFind\n");
+  appDebug("LispFind\n");
   EditorPane *active = splitScreenGetActivePane();
   struct buffer_t *buffer = bufferFindById(active->buffer_id);
   bufferFind(buffer);
   return lisp_null();
 }
 
+/**
+ * @brief Lisp function to search for text
+ * @details Wrapper around editorFind() for use in Lisp keybindings.
+ * @param args Lisp arguments (unused)
+ * @param e Error pointer for Lisp error handling
+ * @param ctx Lisp context
+ * @return lisp_null()
+ * @see editorFind()
+ */
+Lisp bufferFindReverse_L(Lisp args, LispError *e, LispContext ctx) {
+  appDebug("LispFind\n");
+  EditorPane *active = splitScreenGetActivePane();
+  struct buffer_t *buffer = bufferFindById(active->buffer_id);
+  bufferFindReverse(buffer);
+  return lisp_null();
+}
+
 /**
  * @brief Lisp function to read character at cursor
- * @details Returns the character at the current cursor position as a Lisp character.
- * Returns 'a' if at end of line.
+ * @details Returns the character at the current cursor position as a Lisp
+ * character. Returns 'a' if at end of line.
  * @param args Lisp arguments (unused)
  * @param e Error pointer for Lisp error handling
  * @param ctx Lisp context
@@ -460,11 +463,10 @@ Lisp editorReadChar_L(Lisp args, LispError *e, LispContext ctx) {
   Lisp returned_char;
   EditorPane *active = splitScreenGetActivePane();
   struct buffer_t *buffer = bufferFindById(active->buffer_id);
-  if (buffer->row[active->cursor_y].render[active->cursor_x] == 0) {
+  if (buffer->row[buffer->y].chars[buffer->x] == 0) {
     returned_char = lisp_make_char('a');
   } else {
-    
-     returned_char = lisp_make_char(buffer->row[active->cursor_y].render[active->cursor_x]); 
+    returned_char = lisp_make_char(buffer->row[buffer->y].chars[buffer->x]);
   }
   return returned_char;
 }
@@ -488,7 +490,7 @@ Lisp editorSetPrefix(Lisp args, LispError *e, LispContext ctx) {
   struct prefix_t prefix = find_prefix(prefix_name);
   E.prefix_state = prefix.prefix_id;
   editorSetStatusMessage("prefix %s", prefix.prefix_name);
-  fprintf(stderr, "%s set\n", prefix_name);
+  appDebug("%s set\n", prefix_name);
 
   return lisp_null();
 }
@@ -511,3 +513,49 @@ Lisp editorPrefix(Lisp args, LispError *e, LispContext ctx) {
           64);
   return lisp_null();
 }
+
+Lisp editorPaste(Lisp args, LispError *e, LispContext ctx)
+{
+  const char *char_to_paste = editorGetClipboard();
+  appDebug("editor-paste, %s\n", char_to_paste);
+  bufferInsertBytes(char_to_paste, (int) strlen(char_to_paste));
+  return lisp_null();
+}
+
+Lisp editorCutEndLine(Lisp args, LispError *e, LispContext ctx)
+{
+  EditorPane *active = splitScreenGetActivePane();
+  struct buffer_t *buffer = bufferFindById(active->buffer_id);
+  int bytes_to_delete = buffer->row[buffer->y].size - buffer->x;
+  editorSetClipboard(&buffer->row[buffer->y].chars[buffer->x], bytes_to_delete);
+  buffer->x = buffer->row[buffer->y].size;
+  while (bytes_to_delete--)
+  {
+    bufferDelBytes();
+  }
+  return lisp_null();
+}
+
+Lisp editorMoveBegBuffer(Lisp args, LispError *e, LispContext ctx)
+{
+  EditorPane *active = splitScreenGetActivePane();
+  struct buffer_t *buffer = bufferFindById(active->buffer_id);
+  buffer->x = 0;
+  buffer->y = 0;
+  return lisp_null();
+}
+
+Lisp editorMoveEndBuffer(Lisp args, LispError *e, LispContext ctx)
+{
+  EditorPane *active = splitScreenGetActivePane();
+  struct buffer_t *buffer = bufferFindById(active->buffer_id);
+  buffer->x = buffer->row[buffer->numrows-1].size;
+  buffer->y = buffer->numrows-1;
+  return lisp_null();
+}
+
+Lisp editorAutoComplete(Lisp args, LispError *e, LispContext ctx)
+{
+  createContextBuffer(E.cursor_x - 2, E.cursor_y + 1, "hello");
+  return lisp_null();
+}

src/editor_op.c

@@ -1,10 +1,13 @@
+#include "../include/editor_op.h"
+
 #include <stdarg.h>
 
-#include "../include/editor_op.h"
 #include "../include/row_op.h"
-#include "include/buffer.h"
-#include "include/data.h"
-#include "include/split_screen.h"
+#include "../include/buffer.h"
+#include "../include/data.h"
+#include "../include/split_screen.h"
+#include "../include/terminal.h"
+#include "../include/utf8.h"
 
 
 extern struct editorConfig E;
@@ -19,64 +22,109 @@ extern struct editorConfig E;
  * @note Updates global editor state E (status_msg, status_msg_time)
  * @see editorDrawMessageBar()
  */
-void editorSetStatusMessage(const char *fmt, ...) {
-  va_list ap;
-  va_start(ap, fmt);
-  vsnprintf(E.status_msg, sizeof(E.status_msg), fmt, ap);
-  va_end(ap);
-  E.status_msg_time = time(NULL);
+void editorSetStatusMessage(const char* fmt, ...)
+{
+    va_list ap;
+    va_start(ap, fmt);
+    vsnprintf(E.status_msg, E.screencols, fmt, ap);
+    va_end(ap);
+    E.status_msg_time = time(NULL);
 }
 
+/**
+ * @brief Moves the cursor based on arrow key input
+ * @details Updates cursor position (E.cursor_x, E.cursor_y) based on the given
+ * key direction. Handles line wrapping and boundary conditions. Prevents cursor
+ * from exceeding line lengths.
+ * @param key The arrow key code (ARROW_UP, ARROW_DOWN, ARROW_LEFT, ARROW_RIGHT)
+ * @return 1 if cursor movement was valid, 0 if cursor was constrained to line boundary
+ * @note Updates global editor state E
+ */
+int editorMoveCursor(int key) {
+    EditorPane *active = splitScreenGetActivePane();
+    struct buffer_t *buf = bufferFindById(active->buffer_id);
+    row_t *row = &buf->row[buf->y];
+    switch (key) {
+    case ARROW_RIGHT:
+        if (row && buf->x < row->size) {
+            int len = utf8Seqlen(row->chars[buf->x]);
+            buf->x += len;
+        } else if (row && buf->y < buf->numrows) {
+            buf->y++;
+            buf->x = 0;
+        }
+        break;
+    case ARROW_DOWN:
+        if (buf->y < buf->numrows) {
 
-void bufferInsertChar(int c) {
-  EditorPane *active = splitScreenGetActivePane();
-  struct buffer_t *buf = bufferFindById(active->buffer_id);
-    if (active->cursor_y == buf->numrows) {
-      bufferInsertRow(buf, buf->numrows, "", 0);
+            buf->y++;
+        }
+        break;
+    case ARROW_UP:
+        if (buf->y != 0) {
+            --buf->y;
+        }
+        break;
+    case ARROW_LEFT:
+        if (buf->x != 0) {
+            --buf->x;
+        } else if (buf->y > 0) {
+            --buf->y;
+            buf->x = buf->row[buf->y].size;
+        }
+        break;
     }
-    bufferRowInsertChar(buf, &buf->row[active->cursor_y], active->cursor_x, c);
-    active->cursor_x++;
+    return 1;
 }
 
-void bufferInsertNewLine() {
-  /*
-   * Add new line and place the cursor at the beginning of it
-   */
-  fprintf(stderr, "Inserting new line\n");
-    EditorPane *active = splitScreenGetActivePane();
-  struct buffer_t *buf = bufferFindById(active->buffer_id);
-  frow *row;
-  if (!active->cursor_x) {
-    bufferInsertRow(buf, active->cursor_y, "", 0);
-  } else {
-    row = &buf->row[active->cursor_y];
-    bufferInsertRow(buf, active->cursor_y + 1, &row->chars[active->cursor_x],
-                    row->size - active->cursor_x);
-    row = &buf->row[active->cursor_y];
-    row->size = active->cursor_x;
-    row->chars[row->size] = '\0';
-    bufferUpdatfrow(row);
-  }
-  ++active->cursor_y;
-  active->cursor_x = 0;
-  fprintf(stderr, "Insert new line done\n");
+char *editorGetClipboard(void) {
+    FILE *pipe = popen(CLIPBOARD_PASTE_CMD, "r");
+    if (!pipe) return NULL;
+
+    size_t cap = 4096;
+    size_t len = 0;
+    char *buf = malloc(cap);
+
+    int c;
+    while ((c = fgetc(pipe)) != EOF) {
+        if (len + 1 >= cap) {
+            cap *= 2;
+            buf = realloc(buf, cap);
+        }
+        buf[len++] = (char)c;
+    }
+    buf[len] = '\0';
+    pclose(pipe);
+    return buf; // caller must free
 }
 
-void bufferDelChar() {
-  frow *row;
-    EditorPane *active = splitScreenGetActivePane();
-  struct buffer_t *buf = bufferFindById(active->buffer_id);
-  if (active->cursor_y == buf->numrows || !(active->cursor_x || active->cursor_y)) {
-    return;
-  }
-  row = &buf->row[active->cursor_y];
-  if (active->cursor_x > 0) {
-    bufferRowDelchar(buf, row, active->cursor_x - 1);
-    --active->cursor_x;
-  } else {
-    active->cursor_x = buf->row[active->cursor_y - 1].size;
-    bufferRowAppendString(buf, &buf->row[active->cursor_y - 1], row->chars, row->size);
-    bufferDelRow(buf, active->cursor_y);
-    --active->cursor_y;
-  }
+void editorSetClipboard(const char *text, int len) {
+    FILE *pipe = popen(CLIPBOARD_COPY_CMD, "w");
+    if (!pipe) return;
+    fwrite(text, 1, len, pipe);
+    pclose(pipe);
 }
+
+int editorRowCxToByte(const row_t *row, int cursor_x) {
+    int i = 0, col = 0;
+    while (col < cursor_x && i < row->size) {
+        int sl = utf8Seqlen((unsigned char)row->chars[i]);
+        if (sl < 1)
+            sl = 1;
+        col++;
+        i += sl;
+    }
+    return i;
+}
+
+int editorRowCharCount(row_t *row, int x) {
+    int n = 0, i = 0;
+    while (i < x && i < row->size) {
+        int sl = utf8Seqlen((unsigned char)row->chars[i]);
+        if (sl < 1)
+            sl = 1;
+        n++;
+        i += sl;
+    }
+    return n;
+}

src/file_io.c

@@ -9,53 +9,20 @@
 #include "../include/file_io.h"
 #include "../include/editor_op.h"
 #include "../include/input.h"
-#include "include/buffer.h"
-#include "include/data.h"
-#include "include/split_screen.h"
+#include "../include/buffer.h"
+#include "../include/data.h"
+#include "../include/split_screen.h"
+#include "../include/row_op.h"
 #include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
+#include <errno.h>
 
-extern char *strdup(const char *);
-extern ssize_t getline(char **restrict lineptr, size_t *restrict n,
-                       FILE *restrict stream);
-extern int ftruncate(int fd, off_t length);
 extern struct editorConfig E;
 
-/**
- * @brief Converts all editor rows to a single string buffer
- * @details Concatenates all row content into a single allocated buffer with
- * newlines between rows. Useful for file saving and buffer operations.
- * @param buffer_len Pointer to integer where total buffer length will be stored
- * @return Pointer to dynamically allocated buffer containing all row data.
- *         Rows are separated by newline characters.
- * @note Caller is responsible for freeing the returned buffer
- */
-char *bufferRowsToString(struct buffer_t *buf, int *buffer_len) {
-  int tot_len = 0;
-  int j;
-  char *buffer;
-  char *p;
-
-  for (j = 0; j < buf->numrows; ++j) {
-    tot_len += buf->row[j].size + 1;
-  }
-  *buffer_len = tot_len;
-  buffer = malloc(tot_len);
-  p = buffer;
-  for (j = 0; j < buf->numrows; ++j) {
-    memcpy(p, buf->row[j].chars, buf->row[j].size);
-    p += buf->row[j].size;
-    *p = '\n';
-    p++;
-  }
-
-  return buffer;
-}
-
 /**
  * @brief Closes the current file and resets editor state
  * @details Clears all rows, resets cursor position, scroll offsets, and file
@@ -67,12 +34,10 @@ void editorCloseFile(void) {
   struct buffer_t *buf = bufferFindById(active->buffer_id);
   active->cursor_x = 0;
   active->cursor_y = 0;
-  active->rx = 0;
-  active->row_offset = 0;
-  active->col_offset = 0;
+  active->x_offset = 0;
+  active->y_offset = 0;
   for (int i = 0; i < buf->numrows; ++i) {
     free(buf->row[i].chars);
-    free(buf->row[i].render);
   }
   buf->numrows = 0;
   free(buf->row);
@@ -103,14 +68,17 @@ void editorOpen(struct buffer_t* buffer) {
     die("fopen");
 
   char *line = NULL;
-  size_t line_cap = 0;
+  size_t line_cap;
   ssize_t line_len;
 
+  rewind(fp);
+
   while ((line_len = getline(&line, &line_cap, fp)) != -1) {
     while (line_len > 0 &&
            (line[line_len - 1] == '\n' || line[line_len - 1] == '\r')) {
       --line_len;
     }
+    appDebug("line %s\n", line);
     bufferInsertRow(buffer, buffer->numrows, line, line_len);
     free(line);
     line = NULL;
@@ -134,7 +102,6 @@ void editorSave() {
   EditorPane *active = splitScreenGetActivePane();
   struct buffer_t *buffer = bufferFindById(active->buffer_id);
   int len;
-  char *buf;
   int fd;
   if (buffer->filename == NULL) {
     buffer->filename = editorPrompt("Save as: %s (ESC to cancel)", "", 1);
@@ -143,51 +110,21 @@ void editorSave() {
       return;
     }
   }
-  buf = bufferRowsToString(buffer, &len);
   fd = open(buffer->filename, O_RDWR | O_CREAT, 0644);
   if (fd != -1) {
-    if (ftruncate(fd, len) != -1) {
-      if (write(fd, buf, len) == len) {
+    for (int i = 0; i < buffer->numrows; ++i)
+    {
+      len = strlen(buffer->row[i].chars);
+      if (write(fd, buffer->row[i].chars, len) != len) {
         close(fd);
-        free(buf);
-        E.dirty = 0;
-        editorSetStatusMessage("%d bytes written to disk", len);
+        editorSetStatusMessage("Can't save! I/O error: %s", strerror(errno));
+
         return;
       }
+      write(fd, "\n", 1);
     }
+    buffer->dirty = 0;
     close(fd);
   }
-  free(buf);
-  editorSetStatusMessage("Can't save! I/O error: %s", strerror(errno));
-}
-
-/**
- * @brief Searches for a string in the document
- * @details Prompts user for a search query, then searches forward from current
- * cursor position. Updates cursor position to the first match found.
- * @note Updates global editor state E (cursor position, row_offset)
- * @note Search is case-sensitive and operates on rendered line content
- * @note Searches begin from the line after current cursor position
- * @see editorPrompt()
- * @see editorRowRxToCx()
- */
-void bufferFind(struct buffer_t *buf) {
-  fprintf(stderr, "searching\n");
-  char *query = editorPrompt("Search: %s (ESC to cancel)", "", 0);
-  EditorPane *active = splitScreenGetActivePane();
-
-  if (query == NULL)
-    return;
-  int i;
-  for (i = active->cursor_y + 1; i < buf->numrows; i++) {
-    frow *row = &buf->row[i];
-    char *match = strstr(row->render, query);
-    if (match) {
-      active->cursor_y = i;
-      active->cursor_x = bufferRowRxToCx(row, match - row->render);
-      buf->row_offset = buf->numrows;
-      break;
-    }
-  }
-  free(query);
+  editorSetStatusMessage("File saved");
 }

src/init.c

@@ -3,7 +3,7 @@
 #include "../include/color.h"
 #include "../include/data.h"
 #include "../include/terminal.h"
-#include "include/split_screen.h"
+#include "../include/split_screen.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -17,6 +17,7 @@ struct editorConfig;
 void registerBuiltin(char *key_sequence, LispCFunc f) {
   lisp_env_define(E.ctx.p->env, lisp_make_symbol(key_sequence, E.ctx),
                   lisp_make_func(f), E.ctx);
+
 }
 
 void initBuiltins() {
@@ -34,8 +35,8 @@ void initBuiltins() {
   registerBuiltin("editor-open-file", editorOpenFile);
   registerBuiltin("editor-insert-char", editorPrintC);
   registerBuiltin("add-package", addPackage);
-  registerBuiltin("editor-del-row", editorDelRow_L);
   registerBuiltin("buffer-find", bufferFind_L);
+  registerBuiltin("buffer-find-reverse", bufferFindReverse_L);
   registerBuiltin("editor-read-char", editorReadChar_L);
   registerBuiltin("add-prefix", editorPrefix);
   registerBuiltin("editor-set-prefix", editorSetPrefix);
@@ -44,11 +45,16 @@ void initBuiltins() {
   registerBuiltin("editor-split-screen-vertical", l_editorSplitScreenVertical);
   registerBuiltin("editor-switch-next-pane", editorSwitchNextPane);
   registerBuiltin("editor-unify-panes", editorUnifiedPanes);
+  registerBuiltin("editor-paste", editorPaste);
+  registerBuiltin("editor-cut-end-line", editorCutEndLine);
+  registerBuiltin("editor-move-cursor-beg-buffer", editorMoveBegBuffer);
+  registerBuiltin("editor-move-cursor-end-buffer", editorMoveEndBuffer);
 }
 
 void initConfig() {
 
   E.ctx = lisp_init();
+  E.ctx.p->err_port = fopen("log.err", "w");
   E.env = lisp_env(E.ctx);
   lisp_lib_load(E.ctx);
   // Init builtins lisp functions
@@ -62,7 +68,7 @@ void initConfig() {
   lisp_eval(E.ctx_data, &E.ctx_error, E.ctx);
 }
 
-void init_theme() {
+void initTheme() {
   E.constantes.THEME = (char *)lisp_string(
       lisp_eval(lisp_read("THEME", &E.ctx_error, E.ctx), &E.ctx_error, E.ctx));
   if (strcmp(E.constantes.THEME, "dark") == 0) {
@@ -89,23 +95,31 @@ void initEditor() {
   if (getWindowSize(&E.screenrows, &E.screencols) == -1) {
     die("getWindowSize");
   }
+  appDebug("%d %d\n", E.screenrows, E.screencols);
   E.screenrows -= 2;
 
-  
+
   // Init graphics variables
   splitScreenInit();
   EditorPane *active = splitScreenGetActivePane();
+  E.cursor_x = 0;
+  E.cursor_y = 0;
+
   active->cursor_x = 0;
   active->cursor_y = 0;
-  active->rx = 0;
-  active->row_offset = 0;
-  active->col_offset = 0;
+  active->origin_x = 0;
+  active->origin_y = 0;
+  active->width = E.screencols;
+  active->height = E.screenrows;
+
   E.init_file_path = (char *)calloc(256, sizeof(char));
   strcat(E.init_file_path, getenv("HOME"));
   strcat(E.init_file_path, "/.beluga/config/init.lisp");
+  appDebug("%s\n", E.init_file_path);
   E.fd_init_file = fopen(E.init_file_path, "r");
 
   // Status bar
+  E.status_msg = (char *)calloc(E.screencols, sizeof(char));
   E.status_msg[0] = '\0';
   E.status_msg_time = 0;
 
@@ -120,7 +134,7 @@ void initEditor() {
 
   initConfig();
 
-  init_theme();
+  initTheme();
 
   // To modify
 

src/input.c

@@ -2,16 +2,22 @@
 #include "../include/define.h"
 #include "../include/editor_op.h"
 #include "../include/output.h"
+#include "include/data.h"
 #include "include/buffer.h"
 #include "include/data.h"
 #include "include/split_screen.h"
 #include <ctype.h>
+#include <sys/stat.h>
 #include <dirent.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/stat.h>
+#include <unistd.h>
+
+#include "include/terminal.h"
+#include "include/utf8.h"
 
 extern struct editorConfig E;
 
@@ -34,10 +40,10 @@ extern struct editorConfig E;
  * @note Caller is responsible for freeing the returned string
  * @note Uses static buffer internally; may return stale pointers across calls
  */
-const char *file_completion(const char *path) {
+const char *fileCompletion(const char *path) {
   DIR *dir;
   struct dirent *entry;
-  char directory[128];
+  char directory[256];
   char predict[128];
   const char *last_slash;
   int predict_len = 0;
@@ -45,8 +51,8 @@ const char *file_completion(const char *path) {
 
   // path is a directory
   if (path[strlen(path) - 1] == '/') {
-    fprintf(stderr, "[FILE COMP] is dir\n");
-    strncpy(directory, path, 128);
+    appDebug("[FILE COMP] is dir\n");
+    strncpy(directory, path, 256);
   }
 
   // Find dir name
@@ -58,9 +64,9 @@ const char *file_completion(const char *path) {
     strncpy(predict, last_slash + 1, predict_len);
     directory[dir_len] = '\0';
     predict[predict_len] = '\0';
-    fprintf(stderr, "%s %s\n", directory, predict);
+    appDebug("%s %s\n", directory, predict);
   } else {
-    fprintf(stderr, "[FILE COMP] dir not found\n");
+    appDebug("[FILE COMP] dir not found\n");
     return strdup(path);
   }
 
@@ -70,7 +76,7 @@ const char *file_completion(const char *path) {
 
   while ((entry = readdir(dir)) != NULL) {
     if (strncmp(entry->d_name, predict, predict_len) == 0) {
-      static char full_path[512];
+      static char full_path[1024];
       snprintf(full_path, sizeof(full_path), "%s%s", directory, entry->d_name);
 
       struct stat st;
@@ -78,7 +84,7 @@ const char *file_completion(const char *path) {
         strcat(full_path, "/"); // add slash for directories
       }
       closedir(dir);
-      
+
       return strdup(full_path);
     }
   }
@@ -87,7 +93,7 @@ const char *file_completion(const char *path) {
   closedir(dir);
   dir = NULL;
   free(entry);
-  fprintf(stderr, "[FILE COMP] no entries\n");
+  appDebug("[FILE COMP] no entries\n");
   return strdup(path);
 }
 
@@ -106,7 +112,8 @@ const char *file_completion(const char *path) {
  * @note Uses editorReadKey() for input and editorRefreshScreen() for display
  */
 char *editorPrompt(char *prompt, char *placeHolder, char bPathMode) {
-  size_t buf_size = 128;
+  size_t buf_size = 256;
+  appDebug("[FILE COMP] %s %d\n", placeHolder, strlen(placeHolder));
   char *buf = malloc(buf_size);
   size_t buf_len = 0;
   int c = 0;
@@ -132,26 +139,26 @@ char *editorPrompt(char *prompt, char *placeHolder, char bPathMode) {
         return buf;
       }
     } else if (bPathMode && c == '\t') {
-      char path[128];
+      char path[256];
       char *pwd;
       if (buf[0] != '/') {
         pwd = getenv("PWD");
-        fprintf(stderr, "%s\n", pwd);
+        appDebug("%s\n", pwd);
         memcpy(path, pwd, strlen(pwd));
         path[strlen(pwd)] = '/';
         strncat(path, buf, buf_len);
       } else {
         strcpy(path, buf);
       }
-      memset(buf, 0, 128);
+      memset(buf, 0, 256);
       buf_len = 0;
-      char * buf_complete = (char *) file_completion(path);
+      char * buf_complete = (char *) fileCompletion(path);
       strcpy(buf, buf_complete);
       free(buf_complete);
       buf_len = strlen(buf);
       buf[buf_len] = '\0';
 
-    } else if (!iscntrl(c) && c < 128) {
+    } else if (!iscntrl(c) && c < 256) {
       if (buf_len == buf_size - 1) {
         buf_size *= 2;
         buf = realloc(buf, buf_size);
@@ -162,133 +169,7 @@ char *editorPrompt(char *prompt, char *placeHolder, char bPathMode) {
   }
 }
 
-/**
- * @brief Converts a key code to its string representation
- * @details Translates raw key codes (including special keys, control keys,
- * and regular characters) into human-readable string formats suitable for
- * display and keybinding configuration.
- * @param key The key code to convert
- * @return Pointer to static buffer containing the string representation.
- *         Examples: "ENTER", "ARROW-UP", "CTRL-a", "TAB", "DELETE", etc.
- * @note Returns pointer to static buffer; string is overwritten on next call
- * @note Non-printable characters are formatted as "KEY-<number>"
- */
-char *key_to_string(int key) {
-  static char key_str[32];
 
-  char tmp[10];
-  sprintf(tmp, "%d", key);
-
-  // First test enter key
-
-  if (key == '\r') {
-    strcpy(key_str, "ENTER");
-  } else if (key == '\t') {
-    strcpy(key_str, "TAB");
-  } else if (key >= 1 && key <= 26) { // CTRL keys
-    snprintf(key_str, sizeof(key_str), "CTRL-%c", 'a' + key - 1);
-  } else {
-    switch (key) {
-    case ARROW_UP:
-      strcpy(key_str, "ARROW-UP");
-      break;
-    case ARROW_DOWN:
-      strcpy(key_str, "ARROW-DOWN");
-      break;
-    case ARROW_LEFT:
-      strcpy(key_str, "ARROW-LEFT");
-      break;
-    case ARROW_RIGHT:
-      strcpy(key_str, "ARROW-RIGHT");
-      break;
-    case PAGE_UP:
-      strcpy(key_str, "PAGE-UP");
-      fprintf(stderr, "pagr up\n");
-      break;
-    case PAGE_DOWN:
-      strcpy(key_str, "PAGE-DOWN");
-      break;
-    case DEL_KEY:
-      strcpy(key_str, "DEL");
-
-      break;
-    case BACKSPACE:
-      strcpy(key_str, "BACKSPACE");
-      break;
-    case '\r':
-      strcpy(key_str, "ENTER");
-      break;
-    case '\x1b':
-      strcpy(key_str, "ESCAPE");
-      break;
-    case BEG_LINE:
-      strcpy(key_str, "HOME");
-      break;
-    case END_LINE:
-      strcpy(key_str, "END");
-      break;
-    default:
-      // For regular characters
-      if (isprint(key)) {
-        snprintf(key_str, sizeof(key_str), "%c", key);
-      } else {
-        snprintf(key_str, sizeof(key_str), "KEY-%d", key);
-      }
-    }
-  }
-  return key_str;
-}
-
-/**
- * @brief Moves the cursor based on arrow key input
- * @details Updates cursor position (E.cursor_x, E.cursor_y) based on the given
- * key direction. Handles line wrapping and boundary conditions. Prevents cursor
- * from exceeding line lengths.
- * @param key The arrow key code (ARROW_UP, ARROW_DOWN, ARROW_LEFT, ARROW_RIGHT)
- * @return 1 if cursor movement was valid, 0 if cursor was constrained to line boundary
- * @note Updates global editor state E
- */
-int editorMoveCursor(int key) {
-  EditorPane *active = splitScreenGetActivePane();
-  struct buffer_t *buf = bufferFindById(active->buffer_id);
-  frow *row = (active->cursor_y + active->row_offset >= buf->numrows) ? NULL : &buf->row[active->cursor_y + active->row_offset];
-  int row_len;
-  int x = active->cursor_x + active->col_offset;
-  int y = active->cursor_y + active->row_offset;
-  switch (key) {
-  case ARROW_RIGHT:
-    if (row && x < row->size) {
-        active->cursor_x++;
-
-    } else if (row && y == row->size) {
-      active->cursor_y++;
-      active->cursor_x = 0;
-    }
-    break;
-  case ARROW_DOWN:
-    if (y < buf->numrows) {
-
-      active->cursor_y++;
-    }
-    break;
-  case ARROW_UP:
-    if (y != 0) {
-      --active->cursor_y;
-    }
-    break;
-  case ARROW_LEFT:
-    if (x != 0) {
-      --active->cursor_x;
-    } else if (y > 0) {
-      --active->cursor_y;
-      active->cursor_x = buf->row[y].size;
-    }
-    break;
-  }
-    
-    
-  return 1;
-}
 
 /**
  * @brief Executes the command bound to a key sequence
@@ -302,7 +183,7 @@ int editorMoveCursor(int key) {
 int executeKeyBind(char *key_sequence) {
   int i;
   int previous_state = 0;
-  fprintf(stderr, "pressed %s\n", key_sequence);
+  appDebug("pressed %s\n", key_sequence);
   for (i = 0; i < E.number_of_keybinds; ++i) {
     if (!strcmp(key_sequence, E.key_binds[i].key_sequence)) {
       if (E.prefix_state != E.key_binds[i].prefix_id) {
@@ -330,10 +211,13 @@ int executeKeyBind(char *key_sequence) {
  */
 void editorProcessKeypress() {
   int c = editorReadKey();
+  char key_sequence[8];
 
-  if (executeKeyBind(key_to_string(c))) {
+  if (executeKeyBind(keyToString(c))) {
     return;
   }
-  bufferInsertChar(c);
+  int seq_len = utf8Encode(c, key_sequence);
+  appDebug("key seq : %s\n", key_sequence);
+  bufferInsertBytes(key_sequence, seq_len);
   E.quit_times_buffer = E.constantes.QUIT_TIMES;
 }

src/output.c

@@ -8,11 +8,13 @@
 #include "../include/output.h"
 #include "../include/append_buffer.h"
 #include "../include/buffer.h"
+#include "../include/editor_op.h"
 #include "../include/data.h"
 #include "../include/define.h"
 #include "../include/row_op.h"
 #include "../include/split_screen.h"
 #include "../include/syntax_highlighter.h"
+#include "../include/terminal.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -23,127 +25,129 @@ extern struct editorConfig E;
 /**
  * @brief Renders a single pane with its buffer content
  */
-static void editorDrawPane(struct abuf *ab, EditorPane *pane) {
-  if (pane == NULL || pane->buffer_id < 0)
-    return;
-
-  struct buffer_t *buf = bufferFindById(pane->buffer_id);
-  if (buf == NULL)
-    return;
-
-  // Draw content for this pane
-  for (int y = 0; y < pane->height; y++) {
-    int file_row = y + pane->row_offset;
-
-    // Position cursor at start of pane row
+static void editorDrawPane(struct abuf* ab, EditorPane* pane)
+{
+    int file_row;
     char pos_buf[32];
-    int pos_len = snprintf(pos_buf, sizeof(pos_buf), "\x1b[%d;%dH",
-                           pane->start_row + y + 1, pane->start_col + 1);
-    abAppend(ab, pos_buf, pos_len);
+    int pos_len;
+    int byte_len_to_print;
+    int bytes_to_print;
+    char* highlighted;
 
-    // Apply background color (6 bytes for RGB format)
-    abAppend(ab, E.theme.BACKGROUND_COLOR, strlen(E.theme.BACKGROUND_COLOR));
+    if (pane == NULL || pane->buffer_id < 0)
+        return;
 
-    int chars_printed = 0;
+    const struct buffer_t* buf = bufferFindById(pane->buffer_id);
+    if (buf == NULL)
+        return;
 
-    if (file_row >= buf->numrows) {
-      // Empty line - show tilde
-      if (buf->numrows == 0 && y == pane->height / 3) {
-        char welcome[80];
-        int welcome_len =
-            snprintf(welcome, sizeof(welcome), "Buffer %d", pane->buffer_id);
-        if (welcome_len > pane->width)
-          welcome_len = pane->width;
+    // Draw all pane
+    for (int y = 0; y < pane->height; y++)
+    {
+        file_row = y + pane->y_offset;
 
-        int padding = (pane->width - welcome_len) / 2;
-        if (padding) {
-          abAppend(ab, "~", 1);
-          chars_printed++;
-          padding--;
+        // Set cursor at start of pane row
+        pos_len = snprintf(pos_buf, sizeof(pos_buf), "\x1b[%d;%dH",
+                           pane->origin_y + y + 1, pane->origin_x + 1);
+        abAppend(ab, pos_buf, pos_len);
+
+        // Apply background color (6 bytes for RGB format)
+        abAppend(ab, E.theme.BACKGROUND_COLOR, (int) strlen(E.theme.BACKGROUND_COLOR));
+
+
+        // pane line is out of buffer
+        if (file_row >= buf->numrows)
+        {
+            // Empty line - show tilde
+
+            abAppend(ab, "~", 1);
+            for (int i = 0;
+                 i < pane->width - 1;
+                 ++i)
+            {
+                abAppend(ab, " ", 1);
+            }
         }
-        while (padding-- && chars_printed < pane->width) {
-          abAppend(ab, " ", 1);
-          chars_printed++;
+        else
+        {
+
+
+            if (buf->filename[strlen(buf->filename) - 1] == 'c' || buf->filename[strlen(buf->filename) - 1] == 'h')
+            {
+                // Render line with syntax highlighting, constrain to pane width
+                highlighted = highlight_line(
+                    &buf->row[file_row].chars[pane->x_offset], &byte_len_to_print);
+
+                // Print only up to pane width
+                abAppend(ab, highlighted, byte_len_to_print);
+                free(highlighted);
+            }
+            else
+            {
+                // Render basic line
+                bytes_to_print =
+                    buf->row[file_row].size - pane->x_offset < pane->width
+                        ? buf->row[file_row].size - pane->x_offset
+                        : pane->width;
+                abAppend(ab, &buf->row[file_row].chars[pane->x_offset], bytes_to_print);
+            }
+            // Fill remaining space with background color to pane width
+            for (int i = 0;
+                 i < pane->width - editorRowCharCount(&buf->row[file_row], pane->width) + pane->x_offset;
+                 ++i)
+            {
+                abAppend(ab, " ", 1);
+            }
         }
-        abAppend(ab, welcome, welcome_len);
-        chars_printed += welcome_len;
-      } else {
-        abAppend(ab, "~", 1);
-        chars_printed++;
-      }
-    } else {
-      // Render line with syntax highlighting, constrain to pane width
-      int start_offset = pane->col_offset;
-      int visible_len = buf->row[file_row].rsize - start_offset;
-      if (visible_len < 0)
-        visible_len = 0;
-      if (visible_len > pane->width)
-        visible_len = pane->width;
-
-      if (buf->filename[strlen(buf->filename) - 1] == 'c') {
-        int byte_len_to_print;
-
-        char *highlighted = highlight_line(
-            &buf->row[file_row].render[start_offset], &byte_len_to_print);
-
-        // Print only up to pane width
-
-        abAppend(ab, highlighted, byte_len_to_print);
-        free(highlighted);
-      } else {
-        abAppend(ab, &buf->row[file_row].render[start_offset], buf->row[file_row].rsize);
-      }
-
-      chars_printed = visible_len;
     }
-
-    // Fill remaining space with background color to pane width
-    abAppend(ab, E.theme.BACKGROUND_COLOR, strlen(E.theme.BACKGROUND_COLOR));
-    while (chars_printed < pane->width) {
-      abAppend(ab, " ", 1);
-      chars_printed++;
-    }
-
-    // Restore background color at end of line
-  }
 }
 
 /**
  * @brief Renders all panes based on current split configuration
  */
-static void editorDrawAllPanes(struct abuf *ab) {
-  ScreenLayout *layout = splitScreenGetLayout();
+static void editorDrawAllPanes(struct abuf* ab)
+{
+    const ScreenLayout* layout = splitScreenGetLayout();
 
-  if (layout->num_panes == 1) {
-    // Single pane fullscreen
-    editorDrawPane(ab, &layout->panes[0]);
-  } else if (layout->num_panes == 2) {
-    // Draw both panes
-    for (int i = 0; i < 2; i++) {
-      editorDrawPane(ab, &layout->panes[i]);
-
-      // Draw pane border/divider if not the last pane
-      if (layout->mode == SPLIT_VERTICAL && i == 0) {
-        // Draw vertical divider
-        int divider_col = layout->panes[0].width;
-        for (int y = 0; y < layout->panes[0].height; y++) {
-          char pos_buf[32];
-          snprintf(pos_buf, sizeof(pos_buf), "\x1b[%d;%dH", y + 1, divider_col);
-          abAppend(ab, pos_buf, strlen(pos_buf));
-          abAppend(ab, "\x1b[1m|\x1b[0m", 9); // Bold pipe divider
-        }
-      } else if (layout->mode == SPLIT_HORIZONTAL && i == 0) {
-        // Draw horizontal divider
-        int divider_row = layout->panes[0].height;
-        char pos_buf[32];
-        snprintf(pos_buf, sizeof(pos_buf), "\x1b[%d;%dH", divider_row + 1, 1);
-        abAppend(ab, pos_buf, strlen(pos_buf));
-        for (int x = 0; x < E.screencols; x++) {
-          abAppend(ab, "\x1b[1m-\x1b[0m", 9); // Bold dash divider
-        }
-      }
+    if (layout->num_panes == 1)
+    {
+        // Single pane fullscreen
+        editorDrawPane(ab, &layout->panes[0]);
+    }
+    else if (layout->num_panes == 2)
+    {
+        // Draw both panes
+        for (int i = 0; i < 2; i++)
+        {
+            editorDrawPane(ab, &layout->panes[i]);
+
+            // Draw pane border/divider if not the last pane
+            if (layout->mode == SPLIT_VERTICAL && i == 0)
+            {
+                // Draw vertical divider
+                int divider_col = layout->panes[0].width;
+                for (int y = 0; y < layout->panes[0].height; y++)
+                {
+                    char pos_buf[32];
+                    snprintf(pos_buf, sizeof(pos_buf), "\x1b[%d;%dH", y + 1, divider_col);
+                    abAppend(ab, pos_buf, (int) strlen(pos_buf));
+                    abAppend(ab, "\x1b[1m|\x1b[0m", 9); // Bold pipe divider
+                }
+            }
+            else if (layout->mode == SPLIT_HORIZONTAL && i == 0)
+            {
+                // Draw horizontal divider
+                int divider_row = layout->panes[0].height;
+                char pos_buf[32];
+                snprintf(pos_buf, sizeof(pos_buf), "\x1b[%d;%dH", divider_row + 1, 1);
+                abAppend(ab, pos_buf, (int) strlen(pos_buf));
+                for (int x = 0; x < E.screencols; x++)
+                {
+                    abAppend(ab, "\x1b[1m-\x1b[0m", 9); // Bold dash divider
+                }
+            }
+        }
     }
-  }
 }
 
 /**
@@ -153,35 +157,87 @@ static void editorDrawAllPanes(struct abuf *ab) {
  * @note Updates global editor state E
  * @see editorRowCxToRx()
  */
-void editorScroll() {
-  EditorPane *active = splitScreenGetActivePane();
-  struct buffer_t *buf = bufferFindById(active->buffer_id);
-  active->rx = active->cursor_x;
+void editorScroll()
+{
+    EditorPane* active = splitScreenGetActivePane();
+    struct buffer_t* buf = bufferFindById(active->buffer_id);
+    int rel_x, rel_y;
 
-  fprintf(stderr, "%d %d / %d %d\n", active->cursor_x, active->col_offset,
-          active->cursor_y, active->row_offset);
+    // compute relative coordinates
+    rel_x = editorRowCharCount(&buf->row[buf->y], buf->x);
+    appDebug("counting %d\n", rel_x);
+    rel_y = buf->y;
 
-  if (active->cursor_x < 0) {
-    active->cursor_x = 0;
-    active->col_offset = active->col_offset == 0 ? 0 : --active->col_offset;
-  }
+    appDebug("%d %d / %d %d\n", active->cursor_x, active->x_offset,
+             active->cursor_y, active->y_offset);
 
-  if (active->cursor_y < 0) {
-    active->cursor_y = 0;
-    active->row_offset = active->row_offset == 0 ? 0 : --active->row_offset;
-  }
+    while (rel_x != active->cursor_x + active->x_offset ||
+        rel_y != active->cursor_y + active->y_offset)
+    {
+        if (rel_x < active->cursor_x + active->x_offset)
+        {
+            // LEFT
+            if (active->cursor_x == 0 && active->x_offset)
+            {
+                active->x_offset--;
+            } else
+            {
+                active->cursor_x--;
+            }
+        } else
+        {
+            // RIGHT
+            if (rel_x > active->cursor_x + active->x_offset)
+            {
+                if (active->cursor_x == active->width - 1)
+                {
+                    active->x_offset++;
+                } else
+                {
+                    active->cursor_x++;
+                }
+            }
+        }
 
-  if (active->cursor_x == active->width) {
+        if (rel_y < active->cursor_y + active->y_offset)
+        {
+            if (active->cursor_y == 0 && active->y_offset)
+            {
+                active->y_offset--;
+            } else
+            {
+                active->cursor_y--;
+            }
+        }
 
-    active->cursor_x--;
-    active->col_offset++;
-  }
+        if (rel_y > active->cursor_y + active->y_offset)
+        {
+            if (active->cursor_y == active->height - 1)
+            {
+                active->y_offset++;
+            } else
+            {
+                active->cursor_y++;
+            }
+        }
 
-  if (active->cursor_y == active->height) {
+    }
+}
 
-    active->cursor_y--;
-    active->row_offset++;
-  }
+char * basename(char *path)
+{
+    int len = (int) strlen(path);
+
+
+    for(int i=len-1; i>0; i--)
+    {
+        if(path[i]=='/' )
+        {
+            path = path+i+1;
+            break;
+        }
+    }
+    return path;
 }
 
 /**
@@ -192,55 +248,63 @@ void editorScroll() {
  * @param ab Pointer to append buffer structure for accumulating output
  * @note Uses ANSI escape codes for color inversion
  */
-void editorDrawStatusBar(struct abuf *ab) {
-  int len, render_len;
-  char status[80], render_status[80];
-  EditorPane *active = splitScreenGetActivePane();
-  struct buffer_t *buf = bufferFindById(active->buffer_id);
+void editorDrawStatusBar(struct abuf* ab)
+{
+    // TO MODIFY
+    int len, render_len;
+    char status[E.screencols], render_status[E.screencols * 4];
+    EditorPane* active = splitScreenGetActivePane();
+    struct buffer_t* buf = bufferFindById(active->buffer_id);
 
-  abAppend(ab, "\x1b[7m", 4); // inverting colors
+    abAppend(ab, "\x1b[7m", 4); // inverting colors
 
-  const char *mode_str = "";
-  ScreenLayout *layout = splitScreenGetLayout();
-  if (layout->mode == SPLIT_VERTICAL)
-    mode_str = " [V-SPLIT]";
-  else if (layout->mode == SPLIT_HORIZONTAL)
-    mode_str = " [H-SPLIT]";
+    const char* mode_str = "";
+    ScreenLayout* layout = splitScreenGetLayout();
+    if (layout->mode == SPLIT_VERTICAL)
+        mode_str = " [V-SPLIT]";
+    else if (layout->mode == SPLIT_HORIZONTAL)
+        mode_str = " [H-SPLIT]";
 
-  // Build buffer status showing all buffers with dirty indicators
-  char buf_status[200] = "";
-  int offset = 0;
-  for (int i = 0; i < E.number_of_buffer; i++) {
-    struct buffer_t *b = &E.buffers[i];
-    char marker = (b->buffer_id == active->buffer_id) ? '>' : ' ';
-    char dirty_marker = b->dirty ? '*' : ' ';
-    offset += snprintf(&buf_status[offset], sizeof(buf_status) - offset,
-                       "%c%d:%s%c ", marker, b->buffer_id,
-                       b->filename ? b->filename : "[No Name]", dirty_marker);
-  }
-
-  len = snprintf(status, sizeof(status), "%s%s", buf_status, mode_str);
-
-  render_len = snprintf(render_status, sizeof(render_status), "%d/%d",
-                        active->cursor_y + 1, buf->numrows);
-
-  if (len > E.screencols) {
-    len = E.screencols;
-  }
-
-  abAppend(ab, status, len);
-  while (len < E.screencols) {
-    if (E.screencols - len == render_len) {
-      abAppend(ab, render_status, render_len);
-      break;
-    } else {
-      abAppend(ab, " ", 1);
-      ++len;
+    // Build buffer status showing all buffers with dirty indicators
+    char buf_status[1024] = "";
+    int offset = 0;
+    for (int i = 0; i < E.number_of_buffer; i++)
+    {
+        struct buffer_t* b = &E.buffers[i];
+        char marker = (b->buffer_id == active->buffer_id) ? '>' : ' ';
+        char dirty_marker = b->dirty ? '*' : ' ';
+        offset += snprintf(&buf_status[offset], sizeof(buf_status) - offset,
+                           "%c%d:%s%c ", marker, b->buffer_id,
+                           b->filename ? basename(b->filename) : "[No Name]", dirty_marker);
     }
-  }
 
-  abAppend(ab, "\x1b[m", 3); // normal text mode
-  abAppend(ab, "\r\n", 2);
+    len = snprintf(status, sizeof(status), "%s%s", buf_status, mode_str);
+
+    render_len = snprintf(render_status, sizeof(render_status), "%d/%d",
+                          active->cursor_y + 1, buf->numrows);
+
+    if (len > E.screencols)
+    {
+        len = E.screencols;
+    }
+
+    abAppend(ab, status, len);
+    while (len < E.screencols)
+    {
+        if (E.screencols - len == render_len + 1)
+        {
+            abAppend(ab, render_status, render_len);
+            break;
+        }
+        else
+        {
+            abAppend(ab, " ", 1);
+            ++len;
+        }
+    }
+
+    abAppend(ab, "\x1b[m", 3); // normal text mode
+    abAppend(ab, "\r\n", 2);
 }
 
 /**
@@ -250,17 +314,21 @@ void editorDrawStatusBar(struct abuf *ab) {
  * @param ab Pointer to append buffer structure for accumulating output
  * @note Messages are set by editorSetStatusMessage()
  */
-void editorDrawMessageBar(struct abuf *ab) {
-  int msg_len = strlen(E.status_msg);
-  abAppend(ab, ERASE_END_LINE, 3);
-  if (msg_len > E.screencols) {
-    msg_len = E.screencols;
-  }
-  if (msg_len && time(NULL) - E.status_msg_time < 5) {
-    abAppend(ab, E.status_msg, msg_len);
-  }
+void editorDrawMessageBar(struct abuf* ab)
+{
+    int msg_len = (int) strlen(E.status_msg);
+    abAppend(ab, ERASE_END_LINE, 3);
+    if (msg_len > E.screencols)
+    {
+        msg_len = E.screencols;
+    }
+    if (msg_len && time(NULL) - E.status_msg_time < 5)
+    {
+        abAppend(ab, E.status_msg, msg_len);
+    }
 }
 
+
 /**
  * @brief Performs complete screen refresh and buffer synchronization
  * @details Clears screen, redraws all visible content (rows, status bar,
@@ -272,33 +340,36 @@ void editorDrawMessageBar(struct abuf *ab) {
  * @see editorDrawMessageBar()
  */
 
-void editorRefreshScreen() {
-  struct abuf ab = ABUF_INIT;
-  char buf[32];
+void editorRefreshScreen()
+{
+    struct abuf ab = ABUF_INIT;
+    char buf[32];
 
-  abAppend(&ab, HIDE_CURSOR, 6);
-  abAppend(&ab, CURSOR_TOP_LEFT, 3);
-  abAppend(&ab, E.theme.BACKGROUND_COLOR,
-           strlen(E.theme.BACKGROUND_COLOR)); // RGB background is 12 bytes
+    abAppend(&ab, HIDE_CURSOR, 6);
+    abAppend(&ab, CURSOR_TOP_LEFT, 3);
+    abAppend(&ab, E.theme.BACKGROUND_COLOR,
+             (int) strlen(E.theme.BACKGROUND_COLOR)); // RGB background is 12 bytes
 
-  // Draw all panes
-  editorScroll();
-  editorDrawAllPanes(&ab);
+    // Draw all panes
+    editorScroll();
+    editorDrawAllPanes(&ab);
 
-  // Draw status bar and message bar
-  editorDrawStatusBar(&ab);
-  editorDrawMessageBar(&ab);
+    // Draw status bar and message bar
+    editorDrawStatusBar(&ab);
+    editorDrawMessageBar(&ab);
+    // editorDrawContextBuffer(&ab);
 
-  // Position cursor in active pane
-  EditorPane *active = splitScreenGetActivePane();
-  if (active != NULL) {
-    snprintf(buf, sizeof(buf), "\x1b[%d;%dH",
-             active->cursor_y + active->start_row + 1,
-             active->cursor_x + active->start_col + 1);
-    abAppend(&ab, buf, strlen(buf));
-  }
+    // Position cursor in active pane
+    EditorPane* active = splitScreenGetActivePane();
+    if (active != NULL)
+    {
+        snprintf(buf, sizeof(buf), "\x1b[%d;%dH",
+                 active->cursor_y + active->origin_y + 1,
+                 active->cursor_x + active->origin_x + 1);
+        abAppend(&ab, buf, (int) strlen(buf));
+    }
 
-  abAppend(&ab, SHOW_CURSOR, 6);
-  write(STDOUT_FILENO, ab.b, ab.len);
-  abFree(&ab);
+    abAppend(&ab, SHOW_CURSOR, 6);
+    write(STDOUT_FILENO, ab.b, ab.len);
+    abFree(&ab);
 }

src/row_op.c

@@ -1,4 +1,6 @@
 #include "../include/row_op.h"
+#include "../include/data.h"
+#include "../include/utf8.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -6,147 +8,5 @@
 
 extern struct editorConfig E;
 
-int bufferRowCxToRx(frow *row, int cursor_x) {
-  int render_x = 0;
-  int i;
-  for (i = 0; i < cursor_x; ++i) {
-    if (row->chars[i] == '\t') {
-      render_x += (E.constantes.TAB_LENGTH - 1) - (render_x % E.constantes.TAB_LENGTH);
-    }
-    render_x++;
-  }
-  return render_x;
-}
 
-int bufferRowRxToCx(frow *row, int rx) {
-  int cur_rx = 0;
-  int cx;
-  for (cx = 0; cx < row->size; cx++) {
-    if (row->chars[cx] == '\t')
-      cur_rx += (E.constantes.TAB_LENGTH - 1) - (cur_rx % E.constantes.TAB_LENGTH);
-    cur_rx++;
-    if (cur_rx > rx) return cx;
-  }
-  return cx;
-}
 
-/**
- * \fn bufferUpdatfrow(frow *row)
- * \brief Copy content of \p row in \p row->render.
- *  */
-
-void bufferUpdatfrow(frow *row) {
-  int i, i_render;
-  int tabs = 0;
-
-  // counting number of tabs
-
-  for (i = 0; i < row->size; ++i) {
-    tabs +=
-        (row->chars[i] == '\t'); /**< increment tabs of 1 if chars[i] is one. */
-  }
-
-  free(row->render);
-  row->render = malloc(row->size + tabs * (E.constantes.TAB_LENGTH - 1) +
-                       1); /**< Tabs needs E.constantes.TAB_LENGTH chars so E.constantes.TAB_LENGTH - 1
-                              more than the first already counted. */
-
-  // end of counting
-  i_render = 0;
-  for (i = 0; i < row->size; ++i) {
-    if (row->chars[i] == '\t') {
-      row->render[i_render++] = ' ';
-      while (i_render % E.constantes.TAB_LENGTH) {
-        row->render[i_render++] =
-            ' '; /**< Addind the right amount of spaces for tabs */
-      }
-    } else {
-      row->render[i_render++] = row->chars[i];
-    }
-  }
-  row->render[i_render] = '\0'; // Don't forget the end of string character.
-  row->rsize = i_render;
-}
-
-void bufferInsertRow(struct buffer_t *buffer, int at, char *s, size_t len) {
-  
-  if (at < 0 || at > buffer->numrows) {
-    
-    return;
-  }
-  frow *tmp = (frow *)realloc(buffer->row, sizeof(frow) * (buffer->numrows + 1));
-  if (!tmp) {
-    return;
-  }
-  buffer->row = tmp;
-  memmove(&buffer->row[at + 1], &buffer->row[at], sizeof(frow) * (buffer->numrows - at));
-
-  buffer->row[at].size = len;
-  buffer->row[at].chars = malloc(len + 1);
-  memcpy(buffer->row[at].chars, s, len);
-  buffer->row[at].chars[len] = '\0';
-
-  buffer->row[at].rsize = 0;
-  buffer->row[at].render = NULL;
-  bufferUpdatfrow(&buffer->row[at]);
-
-  ++buffer->numrows;
-  ++buffer->dirty;
-}
-
-void bufferFrefrow(frow *row) {
-  free(row->render);
-  free(row->chars);
-}
-
-void bufferDelRow(struct buffer_t *buffer, int at) {
-  if (at < 0 || at >= buffer->numrows) {
-    return;
-  }
-  bufferFrefrow(&buffer->row[at]);
-  memmove(&buffer->row[at], &buffer->row[at + 1], sizeof(frow) * (buffer->numrows - at - 1));
-  --buffer->numrows;
-  ++buffer->dirty;
-}
-
-/**
- * \fn bufferRowInsertChar(frow *row, int at, int c)
- * \param at Index of where we want to insert the char */
-
-void bufferRowInsertChar(struct buffer_t *buffer, frow *row, int at, int c) {
-  if (buffer->state == READ_ONLY)
-    return;
-  if (at < 0 || at > row->size) {
-    at = row->size;
-  }
-  row->chars = realloc(row->chars, row->size + 2);
-  memmove(&row->chars[at + 1], &row->chars[at], row->size - at + 1);
-  ++row->size;
-  row->chars[at] = c;
-  bufferUpdatfrow(row);
-  ++buffer->dirty;
-}
-
-void bufferRowAppendString(struct buffer_t *buffer, frow *row, char *s, size_t len) {
-  row->chars = realloc(row->chars, row->size + len + 1);
-  memcpy(&row->chars[row->size], s, len);
-  row->size += len;
-  row->chars[row->size] = '\0';
-  bufferUpdatfrow(row);
-  ++buffer->dirty;
-}
-
-/**
- * \fn bufferRowDelChar(struct bufferConfig *E, frow *frow, int at)
- * \brief Delete the a char at the chosen position on the given row
- * \param at Index of the char to delete
- * \param row Row on operation is made */
-void bufferRowDelchar(struct buffer_t *buffer, frow *row, int at) {
-  if (at < 0 || at >= row->size) {
-    return;
-  }
-  memmove(&row->chars[at], &row->chars[at + 1], row->size - at);
-  --row->size;
-  bufferUpdatfrow(row);
-  ++buffer->dirty;
-}

src/split_screen.c

@@ -18,19 +18,19 @@ void splitScreenInit(void) {
     E.layout.mode = SPLIT_NONE;
     E.layout.num_panes = 1;
     E.layout.active_pane = 0;
-    
+
     E.layout.panes = malloc(sizeof(EditorPane) * 2);
-    
+
     // Initialize single fullscreen pane
     E.layout.panes[0].buffer_id = -1; // No buffer for now
-    E.layout.panes[0].start_row = 0;
-    E.layout.panes[0].start_col = 0;
+    E.layout.panes[0].origin_y = 0;
+    E.layout.panes[0].origin_x = 0;
     E.layout.panes[0].height = E.screenrows - 2;  // Leave room for status bar
     E.layout.panes[0].width = E.screencols;
     E.layout.panes[0].cursor_x = 0;
     E.layout.panes[0].cursor_y = 0;
-    E.layout.panes[0].row_offset = 0;
-    E.layout.panes[0].col_offset = 0;
+    E.layout.panes[0].y_offset = 0;
+    E.layout.panes[0].x_offset = 0;
     E.layout.panes[0].is_active = 1;
 }
 
@@ -47,40 +47,40 @@ int splitScreenVertical(int buffer_id_left, int buffer_id_right) {
         editorSetStatusMessage("Error: invalid buffer IDs");
         return -1;
     }
-    
+
     // Reallocate panes array
     E.layout.panes = realloc(E.layout.panes, sizeof(EditorPane) * 2);
     E.layout.mode = SPLIT_VERTICAL;
     E.layout.num_panes = 2;
     E.layout.active_pane = 0;
-    
+
     int half_width = E.screencols / 2;
-    int pane_height = E.screenrows - 2;  // Leave room for status bar
-    
+    int pane_height = E.screenrows;  // Leave room for status bar
+
     // Left pane
     E.layout.panes[0].buffer_id = buffer_id_left;
-    E.layout.panes[0].start_row = 0;
-    E.layout.panes[0].start_col = 0;
+    E.layout.panes[0].origin_y = 0;
+    E.layout.panes[0].origin_x = 0;
     E.layout.panes[0].height = pane_height;
     E.layout.panes[0].width = half_width;
     E.layout.panes[0].cursor_x = 0;
     E.layout.panes[0].cursor_y = 0;
-    E.layout.panes[0].row_offset = 0;
-    E.layout.panes[0].col_offset = 0;
+    E.layout.panes[0].y_offset = 0;
+    E.layout.panes[0].x_offset = 0;
     E.layout.panes[0].is_active = 1;
-    
+
     // Right pane
     E.layout.panes[1].buffer_id = buffer_id_right;
-    E.layout.panes[1].start_row = 0;
-    E.layout.panes[1].start_col = half_width;
+    E.layout.panes[1].origin_y = 0;
+    E.layout.panes[1].origin_x = half_width;
     E.layout.panes[1].height = pane_height;
     E.layout.panes[1].width = E.screencols - half_width;
     E.layout.panes[1].cursor_x = 0;
     E.layout.panes[1].cursor_y = 0;
-    E.layout.panes[1].row_offset = 0;
-    E.layout.panes[1].col_offset = 0;
+    E.layout.panes[1].y_offset = 0;
+    E.layout.panes[1].x_offset = 0;
     E.layout.panes[1].is_active = 0;
-    
+
     editorSetStatusMessage("Vertical split: %d | %d", buffer_id_left, buffer_id_right);
     return 0;
 }
@@ -98,39 +98,39 @@ int splitScreenHorizontal(int buffer_id_top, int buffer_id_bottom) {
         editorSetStatusMessage("Error: invalid buffer IDs");
         return -1;
     }
-    
+
     // Reallocate panes array
     E.layout.panes = realloc(E.layout.panes, sizeof(EditorPane) * 2);
     E.layout.mode = SPLIT_HORIZONTAL;
     E.layout.num_panes = 2;
     E.layout.active_pane = 0;
-    
+
     int half_height = (E.screenrows - 2) / 2;  // Account for status bar
-    
+
     // Top pane
     E.layout.panes[0].buffer_id = buffer_id_top;
-    E.layout.panes[0].start_row = 0;
-    E.layout.panes[0].start_col = 0;
+    E.layout.panes[0].origin_y = 0;
+    E.layout.panes[0].origin_x = 0;
     E.layout.panes[0].height = half_height;
     E.layout.panes[0].width = E.screencols;
     E.layout.panes[0].cursor_x = 0;
     E.layout.panes[0].cursor_y = 0;
-    E.layout.panes[0].row_offset = 0;
-    E.layout.panes[0].col_offset = 0;
+    E.layout.panes[0].y_offset = 0;
+    E.layout.panes[0].x_offset = 0;
     E.layout.panes[0].is_active = 1;
-    
+
     // Bottom pane
     E.layout.panes[1].buffer_id = buffer_id_bottom;
-    E.layout.panes[1].start_row = half_height;
-    E.layout.panes[1].start_col = 0;
+    E.layout.panes[1].origin_y = half_height;
+    E.layout.panes[1].origin_x = 0;
     E.layout.panes[1].height = E.screenrows - 2 - half_height;
     E.layout.panes[1].width = E.screencols;
     E.layout.panes[1].cursor_x = 0;
     E.layout.panes[1].cursor_y = 0;
-    E.layout.panes[1].row_offset = 0;
-    E.layout.panes[1].col_offset = 0;
+    E.layout.panes[1].x_offset = 0;
+    E.layout.panes[1].y_offset = 0;
     E.layout.panes[1].is_active = 0;
-    
+
     editorSetStatusMessage("Horizontal split: %d / %d", buffer_id_top, buffer_id_bottom);
     return 0;
 }
@@ -142,13 +142,13 @@ void splitScreenUnify(void) {
     E.layout.mode = SPLIT_NONE;
     E.layout.num_panes = 1;
     E.layout.active_pane = 0;
-    
-    E.layout.panes[0].start_row = 0;
-    E.layout.panes[0].start_col = 0;
-    E.layout.panes[0].height = E.screenrows - 2;
+
+    E.layout.panes[0].origin_x = 0;
+    E.layout.panes[0].origin_y = 0;
+    E.layout.panes[0].height = E.screenrows;
     E.layout.panes[0].width = E.screencols;
     E.layout.panes[0].is_active = 1;
-    
+
     editorSetStatusMessage("Unified view");
 }
 
@@ -161,17 +161,17 @@ int splitScreenSwitchPane(void) {
         editorSetStatusMessage("No split to switch");
         return -1;
     }
-    
+
     // Deactivate current pane
     E.layout.panes[E.layout.active_pane].is_active = 0;
-    
+
     // Move to next pane
     E.layout.active_pane = (E.layout.active_pane + 1) % E.layout.num_panes;
-    
+
     // Activate new pane
     E.layout.panes[E.layout.active_pane].is_active = 1;
-    
-    editorSetStatusMessage("Switched to pane %d (buffer %d)", 
+
+    editorSetStatusMessage("Switched to pane %d (buffer %d)",
                           E.layout.active_pane,
                           E.layout.panes[E.layout.active_pane].buffer_id);
     return 0;
@@ -187,15 +187,15 @@ int splitScreenSetPaneBuffer(int buffer_id) {
         editorSetStatusMessage("Error: invalid buffer ID");
         return -1;
     }
-    
+
     EditorPane *active = &E.layout.panes[E.layout.active_pane];
     active->buffer_id = buffer_id;
     active->cursor_x = 0;
     active->cursor_y = 0;
-    active->row_offset = 0;
-    active->col_offset = 0;
-    
-    editorSetStatusMessage("Pane %d now showing buffer %d", 
+    active->origin_x = 0;
+    active->origin_y = 0;
+
+    editorSetStatusMessage("Pane %d now showing buffer %d",
                           E.layout.active_pane, buffer_id);
     return 0;
 }

src/syntax_highlighter.c

@@ -1,5 +1,6 @@
 #include "../include/syntax_highlighter.h"
 #include "../include/data.h"
+#include "../include/utf8.h"
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -8,7 +9,7 @@ extern struct editorConfig E;
 
 const char *c_keywords[] = {
     "if",     "else",     "while",    "for",     "do",       "switch",
-    "case",   "break",    "#include", "#define", "continue", "return",
+    "case",   "break",    "#include", "#define", "#if", "#endif", "#ifndef", "continue", "return",
     "goto",   "struct",   "union",    "enum",    "typedef",  "static",
     "extern", "const",    "volatile", "sizeof",  "auto",     "register",
     "inline", "restrict", NULL};
@@ -18,10 +19,52 @@ const char *c_types[] = {"int",    "char", "float", "double",
                          "void",   "long", "short", "unsigned",
                          "signed", "bool", NULL};
 
+// Returns the byte length of the UTF-8 character starting at s.
+// Never returns 0 for a non-NUL byte, so callers won't infinite-loop.
+static int utf8_char_len(const char *s)
+{
+    unsigned char c = (unsigned char)*s;
+    if (c == 0)              return 0;
+    if (c < 0x80)            return 1;
+    if ((c & 0xE0) == 0xC0)  return 2;
+    if ((c & 0xF0) == 0xE0)  return 3;
+    if ((c & 0xF8) == 0xF0)  return 4;
+    return 1; // continuation byte or invalid — advance 1 to avoid infinite loop
+}
+
+// Copy one full UTF-8 character from src+i into dst+pos, advance both indices.
+static void copy_utf8_char(char *dst, int *dst_pos, const char *src, int *src_pos)
+{
+    int len = utf8_char_len(&src[*src_pos]);
+    for (int b = 0; b < len; b++)
+        dst[(*dst_pos)++] = src[(*src_pos)++];
+}
+
 // Check if character is alphanumeric or underscore
-int is_word_char(char c) {
-  return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') ||
-         (c >= '0' && c <= '9') || c == '_' || c == '#';
+int is_word_char(const char *s)
+{
+    uint32_t cp = utf8Decode(&s);
+
+    if ((cp >= 'a' && cp <= 'z') || (cp >= 'A' && cp <= 'Z') ||
+        (cp >= '0' && cp <= '9') || cp == '_' || cp == '#')
+        return 1;
+
+    if (cp == 0xFFFD) return 0;
+
+    if (cp >= 0x00C0 && cp <= 0x017F) return 1;
+    if (cp >= 0x0370 && cp <= 0x03FF) return 1;
+    if (cp >= 0x0400 && cp <= 0x04FF) return 1;
+    if (cp >= 0x0600 && cp <= 0x06FF) return 1;
+    if (cp >= 0x05D0 && cp <= 0x05EA) return 1;
+    if (cp >= 0x0900 && cp <= 0x097F) return 1;
+    if (cp >= 0x4E00 && cp <= 0x9FFF) return 1;
+    if ((cp >= 0x3040 && cp <= 0x309F) ||
+        (cp >= 0x30A0 && cp <= 0x30FF)) return 1;
+    if (cp >= 0xAC00 && cp <= 0xD7A3) return 1;
+    if ((cp >= 0x0660 && cp <= 0x0669) ||
+        (cp >= 0x06F0 && cp <= 0x06F9)) return 1;
+
+    return 0;
 }
 
 // Check if string is a keyword
@@ -65,26 +108,29 @@ int comment_section = 0;
 // Highlight a line of C code and return the highlighted string
 // Returns a newly allocated string that must be freed by the caller
 char *highlight_line(const char *line, int *length) {
-  char *result = malloc(1024); // Allocate space for result
+  // Each byte can expand to at most (color_prefix + 4 bytes + color_reset).
+  // Allocate generously based on line length to avoid overflow.
+  int line_len = strlen(line);
+  int buf_size = line_len * 32 + 256;
+  char *result = malloc(buf_size);
   int result_pos = 0;
   int i = 0;
 
   while (line[i] != '\0' && line[i] != '\n') {
-    // Skip whitespace
+    // Skip whitespace — copy full UTF-8 char (whitespace is always ASCII,
+    // but using copy_utf8_char keeps the pattern consistent)
     if (line[i] == ' ' || line[i] == '\t') {
-      result[result_pos++] = line[i++];
+      copy_utf8_char(result, &result_pos, line, &i);
       continue;
     }
-    
+
     if (comment_section) {
       result_pos += sprintf(&result[result_pos], "%s", E.theme.COLOR_COMMENT);
       while (line[i] != '\0' && line[i] != '\n') {
-        
-    if (line[i] == '*' && line[i + 1] == '/') {
-      comment_section = 0;
-    }
-
-        result[result_pos++] = line[i++];
+        if (line[i] == '*' && line[i + 1] == '/') {
+          comment_section = 0;
+        }
+        copy_utf8_char(result, &result_pos, line, &i);
       }
       result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
       continue;
@@ -94,14 +140,14 @@ char *highlight_line(const char *line, int *length) {
     if (line[i] == '/' && line[i + 1] == '/') {
       result_pos += sprintf(&result[result_pos], "%s", E.theme.COLOR_COMMENT);
       while (line[i] != '\0' && line[i] != '\n') {
-        result[result_pos++] = line[i++];
+        copy_utf8_char(result, &result_pos, line, &i);
       }
       result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
       continue;
     }
 
     // Handle block comments
-    if ((line[i] == '/' && line[i + 1] == '*')) {
+    if (line[i] == '/' && line[i + 1] == '*') {
       comment_section = 1;
       result_pos += sprintf(&result[result_pos], "%s", E.theme.COLOR_COMMENT);
       result[result_pos++] = line[i++];
@@ -110,9 +156,10 @@ char *highlight_line(const char *line, int *length) {
         if (line[i] == '*' && line[i + 1] == '/') {
           result[result_pos++] = line[i++];
           result[result_pos++] = line[i++];
+          comment_section = 0;
           break;
         }
-        result[result_pos++] = line[i++];
+        copy_utf8_char(result, &result_pos, line, &i);
       }
       result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
       continue;
@@ -125,9 +172,9 @@ char *highlight_line(const char *line, int *length) {
       while (line[i] != '\0' && line[i] != '"') {
         if (line[i] == '\\') {
           result[result_pos++] = line[i++];
-          result[result_pos++] = line[i++];
+          copy_utf8_char(result, &result_pos, line, &i);
         } else {
-          result[result_pos++] = line[i++];
+          copy_utf8_char(result, &result_pos, line, &i);
         }
       }
       if (line[i] == '"')
@@ -143,9 +190,9 @@ char *highlight_line(const char *line, int *length) {
       while (line[i] != '\0' && line[i] != '\'') {
         if (line[i] == '\\') {
           result[result_pos++] = line[i++];
-          result[result_pos++] = line[i++];
+          copy_utf8_char(result, &result_pos, line, &i);
         } else {
-          result[result_pos++] = line[i++];
+          copy_utf8_char(result, &result_pos, line, &i);
         }
       }
       if (line[i] == '\'')
@@ -157,22 +204,26 @@ char *highlight_line(const char *line, int *length) {
     // Handle numbers
     if (line[i] >= '0' && line[i] <= '9') {
       result_pos += sprintf(&result[result_pos], "%s", E.theme.COLOR_NUMBER);
-      while (is_word_char(line[i]) || line[i] == '.') {
-        result[result_pos++] = line[i++];
+      while (is_word_char(&line[i]) || line[i] == '.') {
+        copy_utf8_char(result, &result_pos, line, &i);
       }
       result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
       continue;
     }
 
     // Handle identifiers and keywords
-    if (is_word_char(line[i])) {
+    if (is_word_char(&line[i])) {
       int start = i;
-      while (is_word_char(line[i]))
-        i++;
+      // Advance by full UTF-8 character widths, not single bytes
+      while (line[i] != '\0' && is_word_char(&line[i]))
+        i += utf8_char_len(&line[i]);
 
       char word[256];
-      strncpy(word, &line[start], i - start);
-      word[i - start] = '\0';
+      int word_len = i - start;
+      if (word_len >= (int)sizeof(word))
+        word_len = (int)sizeof(word) - 1;
+      strncpy(word, &line[start], word_len);
+      word[word_len] = '\0';
 
       TokenType type = TOKEN_DEFAULT;
       if (is_keyword(word))
@@ -185,9 +236,9 @@ char *highlight_line(const char *line, int *length) {
       continue;
     }
 
-    // Handle operators and other characters
+    // Handle operators and other characters (including non-ASCII multi-byte)
     result_pos += sprintf(&result[result_pos], "%s", E.theme.COLOR_DEFAULT);
-    result[result_pos++] = line[i++];
+    copy_utf8_char(result, &result_pos, line, &i);
     result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
   }
 

src/terminal.c

@@ -1,7 +1,16 @@
 #include "../include/terminal.h"
-#include "../include/data.h"
 
+#include <ctype.h>
+
+#include "../include/data.h"
+#include "../include/define.h"
+
+#include <stdarg.h>
 #include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "include/utf8.h"
 
 void die(const char *s) {
   write(STDOUT_FILENO, "\x1b[2J", 4);
@@ -35,26 +44,88 @@ void enableRawMode() {
   }
 }
 
-int editorReadKey() {
-  int nread;
-  char c;
-  char seq[3];
-  while ((nread = read(STDIN_FILENO, &c, 1)) != 1) {
-    if (nread == -1 && errno != EAGAIN) {
-      die("read");
+#include <ctype.h> /* isprint */
+
+char *keyToString(int key) {
+  static char key_str[32];
+
+  if (key == '\r') {
+    strcpy(key_str, "ENTER");
+  } else if (key == 0x09) {
+    strcpy(key_str, "TAB");
+  } else if (key >= 1 && key <= 26) {
+    snprintf(key_str, sizeof(key_str), "CTRL-%c", 'a' + key - 1);
+  } else {
+    switch (key) {
+    case ARROW_UP:
+      strcpy(key_str, "ARROW-UP");
+      break;
+    case ARROW_DOWN:
+      strcpy(key_str, "ARROW-DOWN");
+      break;
+    case ARROW_LEFT:
+      strcpy(key_str, "ARROW-LEFT");
+      break;
+    case ARROW_RIGHT:
+      strcpy(key_str, "ARROW-RIGHT");
+      break;
+    case PAGE_UP:
+      strcpy(key_str, "PAGE-UP");
+      break;
+    case PAGE_DOWN:
+      strcpy(key_str, "PAGE-DOWN");
+      break;
+    case DEL_KEY:
+      strcpy(key_str, "DEL");
+      break;
+    case BACKSPACE:
+      strcpy(key_str, "BACKSPACE");
+      break;
+    case BEG_LINE:
+      strcpy(key_str, "HOME");
+      break;
+    case END_LINE:
+      strcpy(key_str, "END");
+      break;
+    case '\x1b':
+      strcpy(key_str, "ESCAPE");
+      break;
+    default:
+      if (key > 127) {
+        /* UTF-8 code point — re-encode into the buffer */
+        char buf[5] = {0};
+        int n = utf8Encode((uint32_t)key, buf);
+        snprintf(key_str, sizeof(key_str), "%.*s", n, buf);
+      } else if (isprint(key)) {
+        snprintf(key_str, sizeof(key_str), "%c", key);
+      } else {
+        snprintf(key_str, sizeof(key_str), "KEY-%d", key);
+      }
     }
   }
+  return key_str;
+}
+
+int editorReadKey() {
+  char c;
+  /* read first byte — may be start of UTF-8 or escape */
+  while (read(STDIN_FILENO, &c, 1) != 1)
+    ;
+  appDebug("f : %hhu %ld\r\n", c, 0x200);
 
   if (c == '\x1b') {
-    if (read(STDIN_FILENO, &seq[0], 1) != 1 ||
-        read(STDIN_FILENO, &seq[1], 1) != 1) {
+    char seq[6];
+    /* try to read escape sequence */
+    if (read(STDIN_FILENO, &seq[0], 1) != 1)
       return '\x1b';
-    }
+    if (read(STDIN_FILENO, &seq[1], 1) != 1)
+      return '\x1b';
+    appDebug("f2 : %s\r\n", seq);
+
     if (seq[0] == '[') {
       if (seq[1] >= '0' && seq[1] <= '9') {
-        if (read(STDIN_FILENO, &seq[2], 1) != 1) {
+        if (read(STDIN_FILENO, &seq[2], 1) != 1)
           return '\x1b';
-        }
         if (seq[2] == '~') {
           switch (seq[1]) {
           case '1':
@@ -74,7 +145,6 @@ int editorReadKey() {
           }
         }
       } else {
-
         switch (seq[1]) {
         case 'A':
           return ARROW_UP;
@@ -90,18 +160,26 @@ int editorReadKey() {
           return END_LINE;
         }
       }
-    } else if (seq[0] == 'O') {
-      switch (seq[1]) {
-      case 'H':
-        return BEG_LINE;
-      case 'F':
-        return END_LINE;
-      }
     }
     return '\x1b';
-  } else {
-    return c;
   }
+
+  /* multi-byte UTF-8: read remaining bytes */
+  int seqlen = utf8Seqlen((unsigned char)c);
+  if (seqlen > 1) {
+    /* pack into a pseudo-codepoint just to pass bytes through;
+       we handle encoding/decoding at the row level */
+    char buf[4] = {c, 0, 0, 0};
+    for (int i = 1; i < seqlen; i++)
+      if (read(STDIN_FILENO, &buf[i], 1) != 1)
+        break;
+    /* decode and return as uint32, but we need int — use high range */
+    const char *p = buf;
+    uint32_t cp = utf8Decode(&p);
+    return (int)cp; /* caller re-encodes when inserting */
+  }
+
+  return (unsigned char)c;
 }
 
 int getCursorPosition(int *rows, int *cols) {
@@ -147,3 +225,14 @@ int getWindowSize(int *rows, int *cols) {
     return 0;
   }
 }
+
+void appDebug(const char *fmt, ...) {
+#ifdef APP_DEBUG
+  va_list ap;
+  char message[256];
+  va_start(ap, fmt);
+  vsnprintf(message, 256, fmt, ap);
+  va_end(ap);
+  fprintf(stderr, "%s\n", message);
+#endif
+}

src/utf8.c

@@ -0,0 +1,147 @@
+/**
+ * @file utf8.c
+ */
+
+#include "../include/utf8.h"
+
+#include <stdint.h>
+#include <unistd.h>
+
+
+uint32_t readUtf8Char(void)
+{
+    unsigned char buf[4];
+
+    read(STDIN_FILENO, &buf[0], 1);
+
+    int extra;
+    uint32_t cp;
+
+    if (buf[0] < 0x80)
+    {
+        cp = buf[0];
+        extra = 0;
+    }
+    else if (buf[0] < 0xC0) { return 0xFFFD; } // stray continuation
+    else if (buf[0] < 0xE0)
+    {
+        cp = buf[0] & 0x1F;
+        extra = 1;
+    }
+    else if (buf[0] < 0xF0)
+    {
+        cp = buf[0] & 0x0F;
+        extra = 2;
+    }
+    else
+    {
+        cp = buf[0] & 0x07;
+        extra = 3;
+    }
+
+    if (extra > 0)
+    {
+        read(STDIN_FILENO, &buf[1], extra); // read remaining bytes at once
+        for (int i = 0; i < extra; i++)
+            cp = (cp << 6) | (buf[1 + i] & 0x3F);
+    }
+
+    return cp;
+}
+
+uint32_t utf8Decode(const char** s)
+{
+    unsigned char c = (unsigned char)**s;
+    uint32_t cp;
+    int extra;
+    if (c < 0x80)
+    {
+        cp = c;
+        extra = 0;
+    }
+    else if (c < 0xC0)
+    {
+        (*s)++;
+        return 0xFFFD;
+    }
+    else if (c < 0xE0)
+    {
+        cp = c & 0x1F;
+        extra = 1;
+    }
+    else if (c < 0xF0)
+    {
+        cp = c & 0x0F;
+        extra = 2;
+    }
+    else
+    {
+        cp = c & 0x07;
+        extra = 3;
+    }
+    (*s)++;
+    while (extra--)
+    {
+        c = (unsigned char)**s;
+        if ((c & 0xC0) != 0x80) return 0xFFFD;
+        cp = (cp << 6) | (c & 0x3F);
+        (*s)++;
+    }
+    return cp;
+}
+
+// buf must have at least 4 bytes; returns bytes written
+int utf8Encode(uint32_t cp, char* buf)
+{
+    if (cp < 0x80)
+    {
+        buf[0] = cp;
+        return 1;
+    }
+    if (cp < 0x800)
+    {
+        buf[0] = 0xC0 | (cp >> 6);
+        buf[1] = 0x80 | (cp & 0x3F);
+        return 2;
+    }
+    if (cp < 0x10000)
+    {
+        buf[0] = 0xE0 | (cp >> 12);
+        buf[1] = 0x80 | ((cp >> 6) & 0x3F);
+        buf[2] = 0x80 | (cp & 0x3F);
+        return 3;
+    }
+    buf[0] = 0xF0 | (cp >> 18);
+    buf[1] = 0x80 | ((cp >> 12) & 0x3F);
+    buf[2] = 0x80 | ((cp >> 6) & 0x3F);
+    buf[3] = 0x80 | (cp & 0x3F);
+    return 4;
+}
+
+int utf8Seqlen(unsigned char c)
+{
+    if (c < 0x80) return 1;
+    if (c < 0xC0) return 0; /* continuation — shouldn't be leading */
+    if (c < 0xE0) return 2;
+    if (c < 0xF0) return 3;
+    return 4;
+}
+
+/**
+ * @param codepoint utf8 codepoint of a char
+ * @return length of the codepoint
+ */
+int codepointWidth(uint32_t codepoint)
+{
+    if (codepoint < 0x20 || codepoint == 0x7F) return 0;
+    /* rough double-width ranges */
+    if ((codepoint >= 0x1100 && codepoint <= 0x115F) ||
+        (codepoint >= 0x2E80 && codepoint <= 0x303E) ||
+        (codepoint >= 0x3041 && codepoint <= 0x33BF) ||
+        (codepoint >= 0xAC00 && codepoint <= 0xD7AF) ||
+        (codepoint >= 0xF900 && codepoint <= 0xFAFF) ||
+        (codepoint >= 0xFF01 && codepoint <= 0xFF60) ||
+        (codepoint >= 0x1F300 && codepoint <= 0x1FAFF))
+        return 2;
+    return 1;
+}