--- lbbs/src/editor.c	2025/06/13 13:39:46	1.19
+++ lbbs/src/editor.c	2025/06/15 13:40:52	1.23
@@ -79,7 +79,7 @@ EDITOR_DATA *editor_data_load(const char
 {
 	EDITOR_DATA *p_editor_data;
 	char *p_data_line = NULL;
-	long line_offsets[MAX_EDITOR_DATA_LINES];
+	long line_offsets[MAX_EDITOR_DATA_LINES + 1];
 	long current_data_line_length = 0;
 	long i;
 
@@ -96,7 +96,7 @@ EDITOR_DATA *editor_data_load(const char
 		return NULL;
 	}
 
-	p_editor_data->display_line_total = split_data_lines(p_data, SCREEN_COLS, line_offsets, MAX_EDITOR_DATA_LINES);
+	p_editor_data->display_line_total = split_data_lines(p_data, SCREEN_COLS, line_offsets, MAX_EDITOR_DATA_LINES + 1);
 
 	for (i = 0; i < p_editor_data->display_line_total; i++)
 	{
@@ -128,8 +128,8 @@ EDITOR_DATA *editor_data_load(const char
 		current_data_line_length += p_editor_data->display_line_lengths[i];
 
 		// Trim \n from last line
-		if (i + 1 == p_editor_data->display_line_total && 
-			p_editor_data->display_line_lengths[i] > 0 && 
+		if (i + 1 == p_editor_data->display_line_total &&
+			p_editor_data->display_line_lengths[i] > 0 &&
 			p_editor_data->p_display_lines[i][p_editor_data->display_line_lengths[i] - 1] == '\n')
 		{
 			p_editor_data->display_line_lengths[i]--;
@@ -227,10 +227,18 @@ int editor_data_insert(EDITOR_DATA *p_ed
 		return -1;
 	}
 
+	// Validate str
+	if ((str_len == 1 && str[0] <= 0) ||
+		(str_len == 2 && (str[0] >= 0 || str[1] >= 0)))
+	{
+		log_error("Invalid input str, len=%d\n", str_len);
+		return -2;
+	}
+
 	// Get accurate offset of first character of CJK at offset position
 	for (i = 0; i < offset; i++)
 	{
-		if (p_editor_data->p_display_lines[display_line][i] < 0 || p_editor_data->p_display_lines[display_line][i] > 127) // GBK
+		if (p_editor_data->p_display_lines[display_line][i] < 0) // GBK
 		{
 			i++;
 		}
@@ -411,12 +419,27 @@ int editor_data_insert(EDITOR_DATA *p_ed
 		}
 	}
 
+	// Prevent the last display line from being over-length
+	if (p_editor_data->display_line_total == MAX_EDITOR_DATA_LINES)
+	{
+		len = split_line(p_editor_data->p_display_lines[p_editor_data->display_line_total - 1], SCREEN_COLS - 1, &eol, &display_len);
+		p_editor_data->p_display_lines[p_editor_data->display_line_total - 1][len] = '\0';
+		p_editor_data->display_line_lengths[p_editor_data->display_line_total - 1] = len;
+		if (*p_display_line + 1 >= p_editor_data->display_line_total)
+		{
+			*p_offset = MIN(*p_offset, len);
+			*p_display_line = p_editor_data->display_line_total - 1;
+		}
+	}
+
 	return 0;
 }
 
-int editor_data_delete(EDITOR_DATA *p_editor_data, long display_line, long offset,
+int editor_data_delete(EDITOR_DATA *p_editor_data, long *p_display_line, long *p_offset,
 					   long *p_last_updated_line)
 {
+	long display_line = *p_display_line;
+	long offset = *p_offset;
 	char *p_data_line = NULL;
 	long len_data_line;
 	long offset_data_line;
@@ -435,7 +458,7 @@ int editor_data_delete(EDITOR_DATA *p_ed
 	// Get accurate offset of first character of CJK at offset position
 	for (i = 0; i < offset; i++)
 	{
-		if (p_editor_data->p_display_lines[display_line][i] < 0 || p_editor_data->p_display_lines[display_line][i] > 127) // GBK
+		if (p_editor_data->p_display_lines[display_line][i] < 0) // GBK
 		{
 			i++;
 		}
@@ -483,7 +506,7 @@ int editor_data_delete(EDITOR_DATA *p_ed
 	{
 		str_len = 1;
 	}
-	else if (p_data_line[offset_data_line + 1] < 0 || p_data_line[offset_data_line] > 127) // GBK
+	else if (p_data_line[offset_data_line + 1] < 0) // GBK
 	{
 		str_len = 2;
 	}
@@ -574,6 +597,9 @@ int editor_data_delete(EDITOR_DATA *p_ed
 		*p_last_updated_line = MAX(j - 1, *p_last_updated_line);
 	}
 
+	// Return real offset
+	*p_offset = offset;
+
 	return str_len;
 }
 
@@ -671,15 +697,16 @@ int editor_display(EDITOR_DATA *p_editor
 					input_str[str_len] = (char)(ch - 256);
 					str_len++;
 				}
-				else
+				else if (str_len > 0)
 				{
+					log_error("Received %d character over 127 followed by character less than 127\n", str_len);
 					str_len = 0;
 				}
 
 				if ((ch >= 32 && ch < 127) || (ch > 127 && ch <= 255 && str_len == 2) || // Printable character or GBK
 					ch == CR || ch == KEY_ESC)											 // Special character
 				{
-					if (str_len == 0)
+					if (str_len == 0) // ch >= 32 && ch < 127
 					{
 						input_str[0] = (char)ch;
 						str_len = 1;
@@ -693,7 +720,7 @@ int editor_display(EDITOR_DATA *p_editor
 
 					if (!key_insert) // overwrite
 					{
-						if (editor_data_delete(p_editor_data, display_line_in, offset_in,
+						if (editor_data_delete(p_editor_data, &display_line_out, &offset_out,
 											   &last_updated_line) < 0)
 						{
 							log_error("editor_data_delete() error\n");
@@ -704,12 +731,9 @@ int editor_display(EDITOR_DATA *p_editor
 										   input_str, str_len, &last_updated_line) < 0)
 					{
 						log_error("editor_data_insert(str_len=%d) error\n", str_len);
-						str_len = 0;
 					}
 					else
 					{
-						str_len = 0;
-
 						output_end_row = MIN(SCREEN_ROWS - 1, output_current_row + (int)(last_updated_line - line_current));
 						line_current -= (output_current_row - row_pos);
 						output_current_row = (int)row_pos;
@@ -737,9 +761,10 @@ int editor_display(EDITOR_DATA *p_editor
 						{
 							row_pos += (display_line_out - display_line_in);
 						}
-						col_pos = offset_out + 1;
+						col_pos = offset_out + 1; // Set col_pos to accurate pos
 					}
 
+					str_len = 0;
 					continue;
 				}
 				else if (ch == KEY_DEL || ch == BACKSPACE) // Del
@@ -753,6 +778,12 @@ int editor_display(EDITOR_DATA *p_editor
 						}
 
 						col_pos--;
+						if (col_pos > 1 &&
+							p_editor_data->p_display_lines[line_current - output_current_row + row_pos][col_pos - 1] < 0) // GBK
+						{
+							col_pos--;
+						}
+
 						if (col_pos < 1 && line_current - output_current_row + row_pos >= 0)
 						{
 							row_pos--;
@@ -760,25 +791,19 @@ int editor_display(EDITOR_DATA *p_editor
 						}
 					}
 
-					if ((str_len = editor_data_delete(p_editor_data, line_current - output_current_row + row_pos, col_pos - 1,
+					display_line_in = line_current - output_current_row + row_pos;
+					offset_in = col_pos - 1;
+					display_line_out = display_line_in;
+					offset_out = offset_in;
+
+					if ((str_len = editor_data_delete(p_editor_data, &display_line_out, &offset_out,
 													  &last_updated_line)) < 0)
 					{
 						log_error("editor_data_delete() error\n");
 					}
 					else
 					{
-						if (ch == BACKSPACE)
-						{
-							for (i = 1; i < str_len; i++)
-							{
-								col_pos--;
-								if (col_pos < 1 && line_current - output_current_row + row_pos >= 0)
-								{
-									row_pos--;
-									col_pos = MAX(1, p_editor_data->display_line_lengths[line_current - output_current_row + row_pos]);
-								}
-							}
-						}
+						col_pos = offset_out + 1; // Set col_pos to accurate pos
 
 						output_end_row = MIN(SCREEN_ROWS - 1, output_current_row + (int)(last_updated_line - line_current));
 						line_current -= (output_current_row - row_pos);
@@ -807,6 +832,7 @@ int editor_display(EDITOR_DATA *p_editor
 						clrline(output_current_row, output_end_row);
 					}
 
+					str_len = 0;
 					continue;
 				}
 
@@ -824,6 +850,12 @@ int editor_display(EDITOR_DATA *p_editor
 					break;
 				case Ctrl('E'): // End of line
 				case KEY_CTRL_RIGHT:
+					if (line_current - output_current_row + row_pos == p_editor_data->display_line_total - 1) // row_pos at end line
+					{
+						// last display line does NOT have \n in the end
+						col_pos = p_editor_data->display_line_lengths[line_current - output_current_row + row_pos] + 1;
+						break;
+					}
 					col_pos = MAX(1, p_editor_data->display_line_lengths[line_current - output_current_row + row_pos]);
 					break;
 				case Ctrl('T'): // Top of screen
@@ -884,6 +916,12 @@ int editor_display(EDITOR_DATA *p_editor
 					if (col_pos > 1)
 					{
 						col_pos--;
+						if (col_pos > 1 &&
+							p_editor_data->p_display_lines[line_current - output_current_row + row_pos][col_pos - 1] < 0 &&
+							p_editor_data->p_display_lines[line_current - output_current_row + row_pos][col_pos - 2] < 0) // GBK
+						{
+							col_pos--;
+						}
 						break;
 					}
 					col_pos = SCREEN_COLS; // continue to KEY_UP
@@ -911,6 +949,11 @@ int editor_display(EDITOR_DATA *p_editor
 				case KEY_RIGHT:
 					if (col_pos < p_editor_data->display_line_lengths[line_current - output_current_row + row_pos])
 					{
+						if (p_editor_data->p_display_lines[line_current - output_current_row + row_pos][col_pos - 1] < 0 &&
+							p_editor_data->p_display_lines[line_current - output_current_row + row_pos][col_pos] < 0) // GBK
+						{
+							col_pos++;
+						}
 						col_pos++;
 						break;
 					}
@@ -922,7 +965,7 @@ int editor_display(EDITOR_DATA *p_editor
 						col_pos = MIN(col_pos, MAX(1, p_editor_data->display_line_lengths[line_current - output_current_row + row_pos]));
 						break;
 					}
-					if (line_current + (screen_row_total - (output_current_row - screen_begin_row)) >= p_editor_data->display_line_total) // Reach end
+					if (line_current - output_current_row + row_pos == p_editor_data->display_line_total - 1) // row_pos at end line
 					{
 						// last display line does NOT have \n in the end
 						col_pos = p_editor_data->display_line_lengths[line_current - output_current_row + row_pos] + 1;