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 /** Text Input Management (Single 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_context.h"
28 #include "gx_system.h"
29 #include "gx_widget.h"
30 #include "gx_single_line_text_input.h"
31 #include "gx_utility.h"
32
33 /**************************************************************************/
34 /* */
35 /* FUNCTION RELEASE */
36 /* */
37 /* _gx_single_line_text_input_position_get PORTABLE C */
38 /* 6.1 */
39 /* AUTHOR */
40 /* */
41 /* Kenneth Maxwell, Microsoft Corporation */
42 /* */
43 /* DESCRIPTION */
44 /* */
45 /* This service positions the text input cursor based on the requested */
46 /* cursor position. The text input cursor index will be calculated */
47 /* based on the x value of the pixel pisition. */
48 /* */
49 /* INPUT */
50 /* */
51 /* text_input Single-line text input */
52 /* widget control block */
53 /* pixel_position X value of pixel position */
54 /* */
55 /* OUTPUT */
56 /* */
57 /* Status Completion status */
58 /* */
59 /* CALLS */
60 /* */
61 /* _gx_widget_font_get Get widget font */
62 /* _gx_widget_border_width_get Get the widget border width */
63 /* _gx_widget_client_get Get client rectangle */
64 /* _gx_utility_utf8_string_character_get Parse utf8 string to */
65 /* multi-byte glyph */
66 /* _gx_system_string_width_get Get the width of a string */
67 /* _gx_system_dirty_mark Mark a widget area dirty */
68 /* _gx_system_dirty_partial_add Mark the partial area of a */
69 /* widget as dirty */
70 /* */
71 /* CALLED BY */
72 /* */
73 /* Application Code */
74 /* GUIX Internal Code */
75 /* */
76 /* RELEASE HISTORY */
77 /* */
78 /* DATE NAME DESCRIPTION */
79 /* */
80 /* 05-19-2020 Kenneth Maxwell Initial Version 6.0 */
81 /* 09-30-2020 Kenneth Maxwell Modified comment(s), */
82 /* resulting in version 6.1 */
83 /* */
84 /**************************************************************************/
_gx_single_line_text_input_position_get(GX_SINGLE_LINE_TEXT_INPUT * text_input,INT pixel_position)85 UINT _gx_single_line_text_input_position_get(GX_SINGLE_LINE_TEXT_INPUT *text_input, INT pixel_position)
86 {
87 GX_TEXT_INPUT_CURSOR *cursor_ptr;
88 GX_CHAR *string_buffer;
89 GX_FONT *gx_font;
90 GX_RECTANGLE client;
91 GX_VALUE width;
92 GX_VALUE cursor_pos;
93 GX_VALUE x_pos;
94 GX_VALUE distance;
95 UINT new_insert_pos;
96 UINT index;
97 UINT glyph_len = 1;
98 GX_STRING utf8_string;
99 GX_STRING string;
100
101 string.gx_string_ptr = text_input -> gx_single_line_text_input_buffer;
102 string.gx_string_length = text_input -> gx_single_line_text_input_string_size;
103
104 cursor_ptr = &text_input -> gx_single_line_text_input_cursor_instance;
105
106 string_buffer = text_input -> gx_single_line_text_input_buffer;
107
108 _gx_widget_font_get((GX_WIDGET *)text_input, text_input -> gx_prompt_font_id, &gx_font);
109
110 _gx_widget_border_width_get((GX_WIDGET *)text_input, &width);
111 _gx_widget_client_get((GX_WIDGET *)text_input, width, &client);
112
113 switch (text_input -> gx_widget_style & GX_STYLE_TEXT_ALIGNMENT_MASK)
114 {
115 case GX_STYLE_TEXT_RIGHT:
116 x_pos = (GX_VALUE)(client.gx_rectangle_right - 1);
117 break;
118
119 case GX_STYLE_TEXT_CENTER:
120 x_pos = (GX_VALUE)(client.gx_rectangle_left + 1 + ((client.gx_rectangle_right - client.gx_rectangle_left + 1) >> 1));
121 break;
122
123 case GX_STYLE_TEXT_LEFT:
124 default:
125 x_pos = (GX_VALUE)(client.gx_rectangle_left + 1);
126 break;
127 }
128
129 x_pos = (GX_VALUE)(x_pos - text_input -> gx_single_line_text_input_xoffset);
130
131 /* Reset mouse down position when it was out of the text show area. */
132 if (pixel_position < client.gx_rectangle_left + 1)
133 {
134 pixel_position = client.gx_rectangle_left + 1;
135 }
136 else if (pixel_position > client.gx_rectangle_right + 1)
137 {
138 pixel_position = client.gx_rectangle_right - 1;
139 }
140
141 /*Compute the distance from the first character position to the mouse down position. */
142 if (pixel_position > x_pos)
143 {
144 distance = (GX_VALUE)(pixel_position - x_pos);
145 }
146 else
147 {
148 distance = 0;
149 }
150
151 new_insert_pos = string.gx_string_length;
152 index = 0;
153 cursor_pos = 0;
154
155 while (string.gx_string_length > 0)
156 {
157 #ifdef GX_UTF8_SUPPORT
158 _gx_utility_utf8_string_character_get(&string, GX_NULL, &glyph_len);
159 #else
160 string.gx_string_ptr++;
161 string.gx_string_length--;
162 #endif
163 utf8_string.gx_string_ptr = string_buffer + index;
164 utf8_string.gx_string_length = glyph_len;
165
166 _gx_system_string_width_get_ext(gx_font, &utf8_string, &width);
167 if ((cursor_pos + width / 2) > distance)
168 {
169 new_insert_pos = index;
170 break;
171 }
172 cursor_pos = (GX_VALUE)(cursor_pos + width);
173 index += glyph_len;
174 }
175
176 /* Update insert position. */
177 text_input -> gx_single_line_text_input_insert_pos = new_insert_pos;
178
179 cursor_pos = (GX_VALUE)(x_pos + cursor_pos);
180
181 if (cursor_pos < client.gx_rectangle_left + 1)
182 {
183 /* Cursor is beyond widget left, adjust text offset to show cursor. */
184 cursor_ptr -> gx_text_input_cursor_pos.gx_point_x = (GX_VALUE)(client.gx_rectangle_left + 1);
185
186 distance = (GX_VALUE)(client.gx_rectangle_left + 1 - cursor_pos);
187 text_input -> gx_single_line_text_input_xoffset = (GX_VALUE)(text_input -> gx_single_line_text_input_xoffset - distance);
188
189 /* Text offset is modified, mark whole text input area dirty. */
190 _gx_system_dirty_mark((GX_WIDGET *)text_input);
191 }
192 else if (cursor_pos > client.gx_rectangle_right - 1)
193 {
194 /* Cursor is beyond widget right, adjust text offset to show cursor. */
195 cursor_ptr -> gx_text_input_cursor_pos.gx_point_x = (GX_VALUE)(client.gx_rectangle_right - 1);
196
197 distance = (GX_VALUE)(cursor_pos - (client.gx_rectangle_right - 1));
198 text_input -> gx_single_line_text_input_xoffset = (GX_VALUE)(text_input -> gx_single_line_text_input_xoffset + distance);
199
200 /* Text offset is modified, mark whole text input area dirty. */
201 _gx_system_dirty_mark((GX_WIDGET *)text_input);
202 }
203 else if (cursor_ptr -> gx_text_input_cursor_pos.gx_point_x != cursor_pos)
204 {
205 /* For this situation, we only need to mark old and new cursor position dirty. */
206 client.gx_rectangle_left = (GX_VALUE)(cursor_ptr -> gx_text_input_cursor_pos.gx_point_x - (cursor_ptr -> gx_text_input_cursor_width >> 1));
207 client.gx_rectangle_right = (GX_VALUE)(client.gx_rectangle_left + cursor_ptr -> gx_text_input_cursor_width);
208 _gx_system_dirty_partial_add((GX_WIDGET *)text_input, &client);
209
210 cursor_ptr -> gx_text_input_cursor_pos.gx_point_x = cursor_pos;
211
212 client.gx_rectangle_left = (GX_VALUE)(cursor_ptr -> gx_text_input_cursor_pos.gx_point_x - (cursor_ptr -> gx_text_input_cursor_width >> 1));
213 client.gx_rectangle_right = (GX_VALUE)(client.gx_rectangle_left + cursor_ptr -> gx_text_input_cursor_width);
214 _gx_system_dirty_partial_add((GX_WIDGET *)text_input, &client);
215 }
216
217 return GX_SUCCESS;
218 }
219
220
