add csv export

engine/todo.c

@@ -55,3 +55,20 @@ char *todo_item_serialize(TodoItem *item, int *buffer_size_out) {
 
   return buffer;
 }
+
+// Exports
+void todo_export_as_csv(TodoItem *items, int item_count, const char *filename) {
+  FILE *file = fopen(filename, "w");
+  if (file == NULL) {
+    perror("Failed to open file for writing");
+    return;
+  }
+
+  // Write CSV header
+  fprintf(file, "Title,Completed\n");
+  for (int i = 0; i < item_count; i++) {
+    fprintf(file, "\"%s\",%s\n", items[i].title,
+            items[i].completed ? "Yes" : "No");
+  }
+  fclose(file);
+}

engine/todo.h

@@ -20,4 +20,7 @@ void todo_print_item(TodoItem *item);
 
 // Serialization
 char *todo_item_serialize(TodoItem *item, int *buffer_size_out);
+
+// Exports
+void todo_export_as_csv(TodoItem *items, int item_count, const char *filename);
 #endif