editor: start with the editor interface

3 files changed, 156 insertions, 4 deletions

diff --git a/src/editor.c b/src/editor.c
new file mode 100644
index 0000000..1087ae4
--- /dev/null
+++ b/src/editor.c
@@ -0,0 +1,116 @@
+/* parc
+ * Copyright (C) 2025 Ekaitz Zarraga <ekaitz@elenq.tech>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include "piece-table.h"
+
+typedef struct _string
+  {
+    char *start;
+    size_t length;
+  }
+string;
+
+void
+string_init (string *str)
+{
+  str->start = NULL;
+  str->length = 0;
+}
+
+string
+read_file (const char *path)
+{
+  /*
+   * The buffer has to be freed later.
+   */
+  string out;
+  FILE *in;
+  char *buff = NULL;
+  size_t read = 0, total_size = 0, block_size = 1024;
+  in = fopen (path, "r"); /* TODO: Error handling!*/
+  do
+    {
+      buff = realloc (buff, sizeof (*buff) * (total_size + block_size));
+      read = fread (buff + total_size, sizeof (*buff), block_size, in);
+      total_size += read;
+    }
+  while (read == block_size );
+  buff = realloc (buff, sizeof (*buff) * total_size);
+  fclose (in);
+
+  out.start = buff;
+  out.length = total_size;
+  return out;
+}
+
+
+
+
+
+typedef struct _editor
+  {
+    piece_table *pt;
+    const char *path;
+    string orig;
+  }
+editor;
+
+/*
+ * https://texteditors.org/cgi-bin/wiki.pl?Implementing_Undo_For_Text_Editors
+ */
+
+editor *
+editor_create (void)
+{
+  editor *ed = malloc (sizeof (*ed));
+  ed->pt = piece_table_create_from_str ("", 0);
+  ed->path = NULL;
+  string_init (&ed->orig);
+  return ed;
+}
+
+void
+editor_open (editor *ed, const char *path)
+{
+  ed->path = path;
+  piece_table_destroy (ed->pt);
+
+  ed->orig = read_file (ed->path);
+  ed->pt = piece_table_create_from_str (ed->orig.start, ed->orig.length);
+}
+
+void
+editor_destroy (editor *ed)
+{
+  free (ed->orig.start);
+  piece_table_destroy (ed->pt);
+  free (ed);
+}
+
+void
+editor_display (editor *ed)
+{
+  /* Debug only */
+  size_t len = piece_table_length (ed->pt);
+  char *disp = malloc (sizeof (*disp) * len + 1);
+  piece_table_to_string (ed->pt, disp, len);
+  printf ("%s", disp);
+  free (disp);
+}
diff --git a/src/editor.h b/src/editor.h
new file mode 100644
index 0000000..d0b382f
--- /dev/null
+++ b/src/editor.h
@@ -0,0 +1,35 @@
+/* parc
+ * Copyright (C) 2025 Ekaitz Zarraga <ekaitz@elenq.tech>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef EDITOR_H
+#define EDITOR_H
+
+typedef struct _editor editor;
+
+editor *editor_create (void);
+void editor_open (editor *ed, const char *path);
+void editor_destroy (editor *ed);
+
+/* TODO */
+void editor_move_cursor (editor *ed, size_t where);
+void editor_insert_at (editor *ed, size_t where, const char *x);
+void editor_delete_at (editor *ed, size_t where, size_t count);
+
+/* Debug only */
+void editor_display (editor *ed);
+
+#endif
diff --git a/src/main.c b/src/main.c
index 045ebdc..7ef8df0 100644
--- a/src/main.c
+++ b/src/main.c
@@ -16,13 +16,14 @@
  */
 
 #include <stdio.h>
-#include "ui.h"
+#include "editor.h"
 
 int
 main (int argc, char* argv[])
 {
-  ui *ui = ui_create ();
-  ui_loop (ui);
-  ui_destroy (ui);
+  editor *ed = editor_create ();
+  editor_open (ed, "src/main.c");
+  editor_display (ed);
+  editor_destroy (ed);
   return 0;
 }