Syntax highlighting and comment

src/syntax_highlighter.c

@@ -0,0 +1,163 @@
+#include "../include/syntax_highlighter.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+const char *c_keywords[] = {
+    "if", "else", "while", "for", "do", "switch", "case", "break",
+    "continue", "return", "goto", "struct", "union", "enum",
+    "typedef", "static", "extern", "const", "volatile", "sizeof",
+    "auto", "register", "inline", "restrict", NULL
+};
+
+// C types
+const char *c_types[] = {
+    "int", "char", "float", "double", "void", "long", "short",
+    "unsigned", "signed", "bool", NULL
+};
+
+// 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 == '_';
+}
+
+// Check if string is a keyword
+int is_keyword(const char *word) {
+    for (int i = 0; c_keywords[i] != NULL; i++) {
+        if (strcmp(word, c_keywords[i]) == 0) return 1;
+    }
+    return 0;
+}
+
+// Check if string is a type
+int is_type(const char *word) {
+    for (int i = 0; c_types[i] != NULL; i++) {
+        if (strcmp(word, c_types[i]) == 0) return 1;
+    }
+    return 0;
+}
+
+// Get color code for token type
+const char *get_color(TokenType type) {
+    switch (type) {
+        case TOKEN_KEYWORD: return COLOR_KEYWORD;
+        case TOKEN_TYPE: return COLOR_TYPE;
+        case TOKEN_STRING: return COLOR_STRING;
+        case TOKEN_COMMENT: return COLOR_COMMENT;
+        case TOKEN_NUMBER: return COLOR_NUMBER;
+        default: return COLOR_DEFAULT;
+    }
+}
+
+// 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
+    int result_pos = 0;
+    int i = 0;
+    
+    while (line[i] != '\0' && line[i] != '\n') {
+        // Skip whitespace
+        if (line[i] == ' ' || line[i] == '\t') {
+            result[result_pos++] = line[i++];
+            continue;
+        }
+        
+        // Handle line comments
+        if (line[i] == '/' && line[i + 1] == '/') {
+            result_pos += sprintf(&result[result_pos], "%s", COLOR_COMMENT);
+            while (line[i] != '\0' && line[i] != '\n') {
+                result[result_pos++] = line[i++];
+            }
+            result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
+            continue;
+        }
+        
+        // Handle block comments
+        if (line[i] == '/' && line[i + 1] == '*') {
+            result_pos += sprintf(&result[result_pos], "%s", COLOR_COMMENT);
+            result[result_pos++] = line[i++];
+            result[result_pos++] = line[i++];
+            while (line[i] != '\0') {
+                if (line[i] == '*' && line[i + 1] == '/') {
+                    result[result_pos++] = line[i++];
+                    result[result_pos++] = line[i++];
+                    break;
+                }
+                result[result_pos++] = line[i++];
+            }
+            result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
+            continue;
+        }
+        
+        // Handle strings
+        if (line[i] == '"') {
+            result_pos += sprintf(&result[result_pos], "%s\"", COLOR_STRING);
+            i++;
+            while (line[i] != '\0' && line[i] != '"') {
+                if (line[i] == '\\') {
+                    result[result_pos++] = line[i++];
+                    result[result_pos++] = line[i++];
+                } else {
+                    result[result_pos++] = line[i++];
+                }
+            }
+            if (line[i] == '"') result[result_pos++] = line[i++];
+            result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
+            continue;
+        }
+        
+        // Handle character literals
+        if (line[i] == '\'') {
+            result_pos += sprintf(&result[result_pos], "%s'", COLOR_STRING);
+            i++;
+            while (line[i] != '\0' && line[i] != '\'') {
+                if (line[i] == '\\') {
+                    result[result_pos++] = line[i++];
+                    result[result_pos++] = line[i++];
+                } else {
+                    result[result_pos++] = line[i++];
+                }
+            }
+            if (line[i] == '\'') result[result_pos++] = line[i++];
+            result_pos += sprintf(&result[result_pos], "%s", COLOR_RESET);
+            continue;
+        }
+        
+        // Handle numbers
+        if (line[i] >= '0' && line[i] <= '9') {
+            result_pos += sprintf(&result[result_pos], "%s", COLOR_NUMBER);
+            while (is_word_char(line[i]) || line[i] == '.') {
+                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])) {
+            int start = i;
+            while (is_word_char(line[i])) i++;
+            
+            char word[256];
+            strncpy(word, &line[start], i - start);
+            word[i - start] = '\0';
+            
+            TokenType type = TOKEN_DEFAULT;
+            if (is_keyword(word)) type = TOKEN_KEYWORD;
+            else if (is_type(word)) type = TOKEN_TYPE;
+            
+            result_pos += sprintf(&result[result_pos], "%s%s%s", 
+                                 get_color(type), word, COLOR_RESET);
+            continue;
+        }
+        
+        // Handle operators and other characters
+        result[result_pos++] = line[i++];
+    }
+
+    result[result_pos] = '\0';
+    *length = result_pos + 1;
+    return result;
+}