From 257f90cff9f73efed81cd36b8e627bed74897112 Mon Sep 17 00:00:00 2001
From: Hadeed Ahmad <hadeedji@gmail.com>
Date: Mon, 11 Sep 2023 16:02:21 +0500
Subject: [PATCH] Fix rx_to_cx bug

---
 src/commands.c |  2 ++
 src/erow.c     | 18 +++++++-----------
 2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/src/commands.c b/src/commands.c
index 570f7a6..56de385 100644
--- a/src/commands.c
+++ b/src/commands.c
@@ -82,6 +82,7 @@ void command_insert_char(char c) {
     input_process_key(ARROW_RIGHT);
 }
 
+// TODO: Is this many simulated keypresses necessary? Is it bad?
 void command_delete_char(void) {
     if (E.current_buf->cy == E.current_buf->n_rows)
         input_process_key(ARROW_LEFT);
@@ -94,6 +95,7 @@ void command_delete_char(void) {
 
         struct erow *prow = E.current_buf->rows[E.current_buf->cy - 1];
 
+        input_process_key(HOME);
         input_process_key(ARROW_UP);
         cursor_move(E.current_buf, prow->n_chars, 0);
 
diff --git a/src/erow.c b/src/erow.c
index 9da9f7f..c47b3db 100644
--- a/src/erow.c
+++ b/src/erow.c
@@ -55,9 +55,8 @@ int erow_cx_to_rx(struct erow *erow, int cx) {
     cx = CLAMP(cx, 0, (int) erow->n_chars);
 
     int rx = 0;
-
-    for (char *c = erow->chars; c < erow->chars + cx; c++) {
-        if (*c == '\t')
+    for (int c_cx = 0; c_cx < cx; c_cx++) {
+        if (erow->chars[c_cx] == '\t')
             rx += KILO_TAB_STOP - (rx % KILO_TAB_STOP);
         else
             rx++;
@@ -70,20 +69,17 @@ int erow_rx_to_cx(struct erow *erow, int rx) {
     if (erow == NULL)
         return 0;
 
-    int cx = 0, c_rx = 0;
-    while ((size_t) cx < erow->n_chars) {
+    rx = CLAMP(rx, 0, (int) erow->n_rchars);
+
+    int cx = 0;
+    for (int c_rx = 0; c_rx < rx; cx++) {
         if (erow->chars[cx] == '\t')
             c_rx += KILO_TAB_STOP - (c_rx % KILO_TAB_STOP);
         else
             c_rx++;
-
-        cx++;
-
-        if (c_rx >= rx)
-            return cx;
     }
 
-    return erow->n_chars;
+    return cx;
 }
 
 void erow_free(struct erow *erow) {