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kilo.c

@@ -18,6 +18,7 @@
 /*** data ***/
 
 struct editorConfig {
+  int cx, cy;
   int screenrows;
   int screencols;
   struct termios orig_termios;
@@ -120,6 +121,23 @@ void abFree(struct abuf *ab) {
 
 /*** input ***/
 
+void editorMoveCursor(char key) {
+  switch (key) {
+    case 'a':
+      E.cx--;
+      break;
+    case 'd':
+      E.cx++;
+      break;
+    case 'w':
+      E.cy--;
+      break;
+    case 's':
+      E.cy++;
+      break;
+  }
+}
+
 void editorProcessKeyPress() {
   char c = editorReadKey();
 
@@ -130,6 +148,12 @@ void editorProcessKeyPress() {
 
       exit(0);
       break;
+    case 'w':
+    case 's':
+    case 'a':
+    case 'd':
+      editorMoveCursor(c);
+      break;
   }
 }
 
@@ -169,7 +193,10 @@ void editorRefreshScreen() {
 
   editorDrawRows(&ab);
 
-  abAppend(&ab, "\x1b[H", 3);
+  char buf[32];
+  snprintf(buf, sizeof(buf), "\x1b[%d;%dH", E.cy + 1, E.cx + 1);
+  abAppend(&ab, buf, strlen(buf));
+
   abAppend(&ab, "\x1b[?25h", 6);
 
   write(STDIN_FILENO, ab.b, ab.len);
@@ -179,6 +206,9 @@ void editorRefreshScreen() {
 /*** init ***/
 
 void initEditor() {
+  E.cx = 0;
+  E.cy = 0;
+
   if (getWindowSize(&E.screenrows, &E.screencols) == -1) die("getWindowSize");
 }