/*************************************************************************** * Copyright (c) 2024 Microsoft Corporation * * This program and the accompanying materials are made available under the * terms of the MIT License which is available at * https://opensource.org/licenses/MIT. * * SPDX-License-Identifier: MIT **************************************************************************/ /**************************************************************************/ /**************************************************************************/ /** */ /** GUIX Component */ /** */ /** Multi Line Text Input Management (Multi Line Text Input) */ /** */ /**************************************************************************/ #define GX_SOURCE_CODE /* Include necessary system files. */ #include "gx_api.h" #include "gx_system.h" #include "gx_multi_line_text_input.h" #include "gx_multi_line_text_view.h" #include "gx_window.h" #include "gx_widget.h" #include "gx_utility.h" #include "gx_scrollbar.h" /**************************************************************************/ /* */ /* FUNCTION RELEASE */ /* */ /* _gx_multi_line_text_input_backspace PORTABLE C */ /* 6.1.7 */ /* AUTHOR */ /* */ /* Kenneth Maxwell, Microsoft Corporation */ /* */ /* DESCRIPTION */ /* */ /* This function deletes a character before the cursor. */ /* */ /* INPUT */ /* */ /* text_input Multi line text input widget */ /* control block */ /* */ /* OUTPUT */ /* */ /* None */ /* */ /* CALLS */ /* */ /* _gx_widget_font_get Retrieve font */ /* _gx_utility_rectangle_resize Increase/Shrink rectangle with*/ /* specified value */ /* _gx_utility_utf8_string_character_get Parses utf8 string to */ /* multi-byte glyph */ /* _gx_utility_string_length_check Test string length */ /* _gx_window_scrollbar_find Find scrollbar for a window */ /* _gx_window_client_width_get Get client width */ /* _gx_scrollbar_reset Reset scrollbar information */ /* _gx_multi_line_text_view_line_cache_update */ /* Update line cache */ /* _gx_multi_line_text_view_display_info_get */ /* Get the number of characters */ /* that a line can display */ /* _gx_multi_line_text_input_char_remove Remove a character */ /* _gx_multi_line_text_input_cursor_pos_update */ /* Update cursor position */ /* according to insert index */ /* _gx_multi_line_text_view_string_total_rows_compute */ /* _gx_system_string_width_get Get string width */ /* _gx_system_dirty_partial_add Add one dirty area to dirty */ /* list */ /* */ /* */ /* CALLED BY */ /* */ /* _gx_multi_line_text_input_keydown_process */ /* */ /* RELEASE HISTORY */ /* */ /* DATE NAME DESCRIPTION */ /* */ /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */ /* 09-30-2020 Kenneth Maxwell Modified comment(s), */ /* resulting in version 6.1 */ /* 06-02-2021 Kenneth Maxwell Modified comment(s), */ /* removed unused variable */ /* assignment, */ /* resulting in version 6.1.7 */ /* */ /**************************************************************************/ UINT _gx_multi_line_text_input_backspace(GX_MULTI_LINE_TEXT_INPUT *text_input) { GX_TEXT_INPUT_CURSOR *cursor_ptr = &text_input -> gx_multi_line_text_input_cursor_instance; GX_MULTI_LINE_TEXT_VIEW *view = (GX_MULTI_LINE_TEXT_VIEW *)text_input; GX_FONT *font; GX_RECTANGLE client; GX_RECTANGLE dirty_rect; UINT insert_pos; INT shift; INT last_visible_line; GX_VALUE line_height; GX_VALUE delete_width; UINT old_text_rows; UINT glyph_len = 1; GX_STRING string; GX_SCROLLBAR *scroll; UINT start_mark = text_input -> gx_multi_line_text_input_start_mark; UINT end_mark = text_input -> gx_multi_line_text_input_end_mark; if (end_mark < start_mark) { return _gx_multi_line_text_input_delete(text_input); } insert_pos = text_input -> gx_multi_line_text_input_text_insert_position; if (insert_pos > 0) { _gx_widget_font_get((GX_WIDGET *)text_input, text_input -> gx_multi_line_text_view_font_id, &font); if (!font) { return GX_FAILURE; } if (start_mark != end_mark) { glyph_len = (UINT)GX_ABS((INT)start_mark - (INT)end_mark); text_input -> gx_multi_line_text_input_start_mark = 0; text_input -> gx_multi_line_text_input_end_mark = 0; string.gx_string_ptr = &text_input -> gx_multi_line_text_view_text.gx_string_ptr[insert_pos - glyph_len]; } else { _gx_multi_line_text_input_cursor_visible(text_input); #ifdef GX_UTF8_SUPPORT _gx_utility_utf8_string_backward_character_length_get(&text_input -> gx_multi_line_text_view_text, (INT)(insert_pos - 1), &glyph_len); #endif /* Get the character to be deleted. */ string.gx_string_ptr = &text_input -> gx_multi_line_text_view_text.gx_string_ptr[insert_pos - glyph_len]; if (string.gx_string_ptr[0] == GX_KEY_CARRIAGE_RETURN || string.gx_string_ptr[0] == GX_KEY_LINE_FEED) { glyph_len = text_input -> gx_multi_line_text_input_new_line_character_size; string.gx_string_ptr = &text_input -> gx_multi_line_text_view_text.gx_string_ptr[insert_pos - glyph_len]; } } string.gx_string_length = glyph_len; /* Get the width of the character to be deleted. */ _gx_system_string_width_get_ext(font, &string, &delete_width); /* Record old shift value. */ shift = text_input -> gx_multi_line_text_view_text_scroll_shift; /* Remove character before cursor. */ _gx_multi_line_text_input_char_remove(text_input, insert_pos - glyph_len, glyph_len); /* Save old text rows. */ old_text_rows = text_input -> gx_multi_line_text_view_text_total_rows; /* Calculate new text rows. */ _gx_multi_line_text_view_string_total_rows_compute((GX_MULTI_LINE_TEXT_VIEW *)text_input); if (old_text_rows != text_input -> gx_multi_line_text_view_text_total_rows) { _gx_window_scrollbar_find((GX_WINDOW *)text_input, GX_TYPE_VERTICAL_SCROLL, &scroll); if (scroll) { /* Reset scrollbar. */ _gx_scrollbar_reset(scroll, GX_NULL); } else { if (text_input -> gx_multi_line_text_view_text_total_rows > view -> gx_multi_line_text_view_cache_size) { _gx_multi_line_text_view_line_cache_update((GX_MULTI_LINE_TEXT_VIEW *)text_input); } } } /* Update text insert position. */ text_input -> gx_multi_line_text_input_text_insert_position -= glyph_len; client = text_input -> gx_window_client; if (text_input -> gx_multi_line_text_view_whitespace) { /* Offset client bounding box. */ _gx_utility_rectangle_resize(&client, (GX_VALUE)(-text_input -> gx_multi_line_text_view_whitespace)); } /* Recalculate cursor position. */ _gx_multi_line_text_input_cursor_pos_update(text_input, GX_TRUE); if (shift == text_input -> gx_multi_line_text_view_text_scroll_shift) { line_height = (GX_VALUE)(font -> gx_font_line_height + text_input -> gx_multi_line_text_view_line_space); if (line_height) { /* Calculate dirty area. */ dirty_rect = client; dirty_rect.gx_rectangle_top = (GX_VALUE)(cursor_ptr -> gx_text_input_cursor_pos.gx_point_y - (line_height << 1)); /* Calculate last visible line. */ last_visible_line = (-text_input -> gx_multi_line_text_view_text_scroll_shift) / line_height; last_visible_line = last_visible_line + (INT)view -> gx_multi_line_text_view_text_visible_rows + 1; if (last_visible_line > (INT)text_input -> gx_multi_line_text_view_text_total_rows) { last_visible_line = (INT)text_input -> gx_multi_line_text_view_text_total_rows; } shift = (last_visible_line + (INT)old_text_rows - (INT)text_input -> gx_multi_line_text_view_text_total_rows) * line_height + shift; shift += client.gx_rectangle_top; if (shift < dirty_rect.gx_rectangle_bottom) { dirty_rect.gx_rectangle_bottom = (GX_VALUE)shift; } _gx_system_dirty_partial_add((GX_WIDGET *)text_input, &dirty_rect); } } else { _gx_system_dirty_mark((GX_WIDGET *)text_input); } } return GX_SUCCESS; }