1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** GUIX Component */
16 /** */
17 /** Multi Line Text Input Management (Multi Line Text Input) */
18 /** */
19 /**************************************************************************/
20
21 #define GX_SOURCE_CODE
22
23
24 /* Include necessary system files. */
25
26 #include "gx_api.h"
27 #include "gx_system.h"
28 #include "gx_window.h"
29 #include "gx_scrollbar.h"
30 #include "gx_multi_line_text_input.h"
31 #include "gx_multi_line_text_view.h"
32 #include "gx_text_input_cursor.h"
33 #include "gx_utility.h"
34 #include "gx_widget.h"
35
36 /**************************************************************************/
37 /* */
38 /* FUNCTION RELEASE */
39 /* */
40 /* _gx_multi_line_text_input_mark_previous PORTABLE C */
41 /* 6.1.7 */
42 /* AUTHOR */
43 /* */
44 /* Kenneth Maxwell, Microsoft Corporation */
45 /* */
46 /* DESCRIPTION */
47 /* */
48 /* This function moves highlight text end mark one character left. */
49 /* */
50 /* INPUT */
51 /* */
52 /* text_input Multi line text input */
53 /* control block */
54 /* */
55 /* OUTPUT */
56 /* */
57 /* None */
58 /* */
59 /* CALLS */
60 /* */
61 /* _gx_text_input_cursor_dirty_rectangle_get */
62 /* Get cursor rectangle */
63 /* _gx_multi_line_text_input_cursor_pos_update */
64 /* Calculate cursor position */
65 /* according to insert index */
66 /* _gx_system_dirty_partial_add Add one dirty area to */
67 /* dirty list */
68 /* _gx_system_dirty_mark Mark widget area dirty */
69 /* _gx_utility_utf8_string_character_get Parses utf8 string to */
70 /* multi-byte glyph */
71 /* _gx_utility_string_length_check Test string length */
72 /* */
73 /* CALLED BY */
74 /* */
75 /* _gx_multi_line_text_input_keydown_process */
76 /* */
77 /* RELEASE HISTORY */
78 /* */
79 /* DATE NAME DESCRIPTION */
80 /* */
81 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */
82 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */
83 /* resulting in version 6.1 */
84 /* 06-02-2021 Kenneth Maxwell Modified comment(s), */
85 /* removed unused variable */
86 /* assignment, */
87 /* resulting in version 6.1.7 */
88 /* */
89 /**************************************************************************/
_gx_multi_line_text_input_mark_previous(GX_MULTI_LINE_TEXT_INPUT * text_input)90 UINT _gx_multi_line_text_input_mark_previous(GX_MULTI_LINE_TEXT_INPUT *text_input)
91 {
92 GX_TEXT_INPUT_CURSOR *cursor_ptr = &text_input -> gx_multi_line_text_input_cursor_instance;
93 GX_CONST GX_CHAR *string;
94 INT old_shift;
95 GX_RECTANGLE cur_rect;
96 UINT glyph_len = 1;
97 UINT cursor_line;
98 GX_POINT start_pos;
99 GX_POINT end_pos;
100 UINT start_mark = text_input -> gx_multi_line_text_input_start_mark;
101 UINT end_mark = text_input -> gx_multi_line_text_input_end_mark;
102
103 if (start_mark == end_mark)
104 {
105 start_mark = text_input -> gx_multi_line_text_input_text_insert_position;
106 end_mark = text_input -> gx_multi_line_text_input_text_insert_position;
107
108 text_input -> gx_multi_line_text_input_start_mark = start_mark;
109 text_input -> gx_multi_line_text_input_end_mark = end_mark;
110 }
111
112 if (end_mark > 0)
113 {
114 cursor_line = (UINT)(text_input -> gx_multi_line_text_input_text_cursor_line - 1);
115 cursor_line = (UINT)(cursor_line - text_input -> gx_multi_line_text_view_first_cache_line);
116
117 #ifdef GX_UTF8_SUPPORT
118 _gx_utility_utf8_string_backward_character_length_get(&text_input -> gx_multi_line_text_view_text,
119 (INT)(end_mark - 1), &glyph_len);
120 #endif
121 string = &text_input -> gx_multi_line_text_view_text.gx_string_ptr[end_mark - glyph_len];
122
123 if (string[0] == GX_KEY_CARRIAGE_RETURN || string[0] == GX_KEY_LINE_FEED)
124 {
125 glyph_len = text_input -> gx_multi_line_text_input_new_line_character_size;
126 }
127
128 text_input -> gx_multi_line_text_input_end_mark -= glyph_len;
129
130 /* Record scroll shift before recalculate cursor position. */
131 old_shift = text_input -> gx_multi_line_text_view_text_scroll_shift;
132
133 start_pos = cursor_ptr -> gx_text_input_cursor_pos;
134
135 text_input -> gx_multi_line_text_input_text_insert_position = text_input -> gx_multi_line_text_input_end_mark;
136
137 _gx_multi_line_text_input_cursor_pos_update(text_input, GX_TRUE);
138
139 /* Dirty mark. */
140 if (old_shift == text_input -> gx_multi_line_text_view_text_scroll_shift)
141 {
142 end_pos = cursor_ptr -> gx_text_input_cursor_pos;
143
144 _gx_multi_line_text_input_text_rectangle_get(text_input, start_pos, end_pos, &cur_rect);
145
146 /* Mark highlight area as dirty. */
147 _gx_system_dirty_partial_add((GX_WIDGET *)text_input, &cur_rect);
148 }
149 else
150 {
151 _gx_system_dirty_mark((GX_WIDGET *)text_input);
152 }
153 }
154 return GX_SUCCESS;
155 }
156
157
