1/*
2 * Copyright (c) 2017, Daniel Gultsch All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification,
5 * are permitted provided that the following conditions are met:
6 *
7 * 1. Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * 2. Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation and/or
12 * other materials provided with the distribution.
13 *
14 * 3. Neither the name of the copyright holder nor the names of its contributors
15 * may be used to endorse or promote products derived from this software without
16 * specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
20 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
23 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
24 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
25 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
27 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30package eu.siacs.conversations.utils;
31
32import android.content.Context;
33import android.graphics.Color;
34import android.graphics.Typeface;
35import android.preference.PreferenceManager;
36import android.text.Editable;
37import android.text.ParcelableSpan;
38import android.text.Spannable;
39import android.text.SpannableString;
40import android.text.Spanned;
41import android.text.TextWatcher;
42import android.text.style.BackgroundColorSpan;
43import android.text.style.ForegroundColorSpan;
44import android.text.style.RelativeSizeSpan;
45import android.text.style.StrikethroughSpan;
46import android.text.style.StyleSpan;
47import android.text.style.TypefaceSpan;
48import android.widget.EditText;
49import android.widget.TextView;
50
51import androidx.annotation.ColorInt;
52import androidx.core.content.ContextCompat;
53
54import com.google.android.material.color.MaterialColors;
55
56import java.util.ArrayList;
57import java.util.Arrays;
58import java.util.List;
59
60import eu.siacs.conversations.R;
61import eu.siacs.conversations.entities.Message;
62import eu.siacs.conversations.ui.adapter.MessageAdapter;
63import eu.siacs.conversations.ui.text.QuoteSpan;
64
65public class StylingHelper {
66
67 public static final int XHTML_IGNORE = 1;
68 public static final int XHTML_REMOVE = 2;
69 public static final int XHTML_EMPHASIS = 3;
70 public static final int XHTML_CODE = 4;
71 public static final int NOLINKIFY = 0xf0;
72
73 private static final List<? extends Class<? extends ParcelableSpan>> SPAN_CLASSES = Arrays.asList(
74 StyleSpan.class,
75 StrikethroughSpan.class,
76 TypefaceSpan.class,
77 ForegroundColorSpan.class,
78 RelativeSizeSpan.class
79 );
80
81 public static void clear(final Editable editable) {
82 final int end = editable.length() - 1;
83 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
84 for (ParcelableSpan span : editable.getSpans(0, end, clazz)) {
85 editable.removeSpan(span);
86 }
87 }
88 }
89
90 public static void format(final Editable editable, int start, int end, @ColorInt int textColor, final boolean composing) {
91 for (ImStyleParser.Style style : ImStyleParser.parse(editable, start, end)) {
92 final int keywordLength = style.getKeyword().length();
93 int keywordLengthStart = keywordLength;
94 if ("```".equals(style.getKeyword())) {
95 int i;
96 for (i = style.getStart(); i < editable.length(); i++) {
97 if (editable.charAt(i) == '\n') break;
98 }
99 keywordLengthStart = i - style.getStart() + 1;
100 }
101
102 editable.setSpan(
103 createSpanForStyle(style),
104 style.getStart() + keywordLengthStart,
105 style.getEnd() - keywordLength + 1,
106 Spanned.SPAN_EXCLUSIVE_EXCLUSIVE |
107 ("*".equals(style.getKeyword()) || "_".equals(style.getKeyword()) ? XHTML_EMPHASIS << Spanned.SPAN_USER_SHIFT : 0) |
108 ("```".equals(style.getKeyword()) && keywordLengthStart > 4 ? XHTML_CODE << Spanned.SPAN_USER_SHIFT : 0) |
109 ("`".equals(style.getKeyword()) || "```".equals(style.getKeyword()) ? NOLINKIFY << Spanned.SPAN_USER_SHIFT : 0)
110 );
111 makeKeywordOpaque(editable, style.getStart(), style.getStart() + keywordLengthStart, textColor, composing);
112 makeKeywordOpaque(editable, style.getEnd() - keywordLength + 1, style.getEnd() + 1, textColor, composing);
113 }
114 }
115
116 public static void format(final Editable editable, @ColorInt int textColor) {
117 format(editable, textColor, false);
118 }
119
120 public static void format(final Editable editable, @ColorInt int textColor, final boolean composing) {
121 int end = 0;
122 Message.MergeSeparator[] spans = editable.getSpans(0, editable.length() - 1, Message.MergeSeparator.class);
123 for (Message.MergeSeparator span : spans) {
124 format(editable, end, editable.getSpanStart(span), textColor, composing);
125 end = editable.getSpanEnd(span);
126 }
127 format(editable, end, editable.length() - 1, textColor, composing);
128 }
129
130 public static void highlight(final TextView view, final Editable editable, final List<String> needles) {
131 for (final String needle : needles) {
132 if (!FtsUtils.isKeyword(needle)) {
133 highlight(view, editable, needle);
134 }
135 }
136 }
137
138 public static List<String> filterHighlightedWords(List<String> terms) {
139 List<String> words = new ArrayList<>();
140 for (String term : terms) {
141 if (!FtsUtils.isKeyword(term)) {
142 StringBuilder builder = new StringBuilder();
143 for (int codepoint, i = 0; i < term.length(); i += Character.charCount(codepoint)) {
144 codepoint = term.codePointAt(i);
145 if (Character.isLetterOrDigit(codepoint)) {
146 builder.append(Character.toChars(codepoint));
147 } else if (builder.length() > 0) {
148 words.add(builder.toString());
149 builder.delete(0, builder.length());
150 }
151 }
152 if (builder.length() > 0) {
153 words.add(builder.toString());
154 }
155 }
156 }
157 return words;
158 }
159
160 private static void highlight(final TextView view, final Editable editable, final String needle) {
161 final int length = needle.length();
162 String string = editable.toString();
163 int start = indexOfIgnoreCase(string, needle, 0);
164 while (start != -1) {
165 int end = start + length;
166 editable.setSpan(new BackgroundColorSpan(MaterialColors.getColor(view, com.google.android.material.R.attr.colorPrimaryFixedDim)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
167 editable.setSpan(new ForegroundColorSpan(MaterialColors.getColor(view, com.google.android.material.R.attr.colorOnPrimaryFixed)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
168 start = indexOfIgnoreCase(string, needle, start + length);
169 }
170
171 }
172
173 static CharSequence subSequence(CharSequence charSequence, int start, int end) {
174 if (start == 0 && charSequence.length() + 1 == end) {
175 return charSequence;
176 }
177 if (charSequence instanceof Spannable spannable) {
178 Spannable sub = (Spannable) spannable.subSequence(start, end);
179 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
180 ParcelableSpan[] spannables = spannable.getSpans(start, end, clazz);
181 for (ParcelableSpan parcelableSpan : spannables) {
182 int beginSpan = spannable.getSpanStart(parcelableSpan);
183 int endSpan = spannable.getSpanEnd(parcelableSpan);
184 if (beginSpan >= start && endSpan <= end) {
185 continue;
186 }
187 sub.setSpan(clone(parcelableSpan), Math.max(beginSpan - start, 0), Math.min(Math.max(sub.length() - 1, 0), endSpan), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
188 }
189 }
190 return sub;
191 } else {
192 return charSequence.subSequence(start, end);
193 }
194 }
195
196 private static ParcelableSpan clone(ParcelableSpan span) {
197 if (span instanceof ForegroundColorSpan) {
198 return new ForegroundColorSpan(((ForegroundColorSpan) span).getForegroundColor());
199 } else if (span instanceof TypefaceSpan) {
200 return new TypefaceSpan(((TypefaceSpan) span).getFamily());
201 } else if (span instanceof StyleSpan) {
202 return new StyleSpan(((StyleSpan) span).getStyle());
203 } else if (span instanceof StrikethroughSpan) {
204 return new StrikethroughSpan();
205 } else {
206 throw new AssertionError("Unknown Span");
207 }
208 }
209
210 private static ParcelableSpan createSpanForStyle(final ImStyleParser.Style style) {
211 return switch (style.getKeyword()) {
212 case "*" -> new StyleSpan(Typeface.BOLD);
213 case "_" -> new StyleSpan(Typeface.ITALIC);
214 case "~" -> new StrikethroughSpan();
215 case "`", "```" -> new TypefaceSpan("monospace");
216 default -> throw new AssertionError("Unknown Style");
217 };
218 }
219
220 private static void makeKeywordOpaque(final Editable editable, int start, int end, @ColorInt int fallbackTextColor, final boolean composing) {
221 QuoteSpan[] quoteSpans = editable.getSpans(start, end, QuoteSpan.class);
222 @ColorInt int textColor = quoteSpans.length > 0 ? quoteSpans[0].getColor() : fallbackTextColor;
223 @ColorInt int keywordColor = transformColor(textColor);
224 if (composing) {
225 if (end-start > 1) {
226 editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE | XHTML_REMOVE << Spanned.SPAN_USER_SHIFT);
227 } else {
228 editable.setSpan(new RelativeSizeSpan(0), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE | XHTML_REMOVE << Spanned.SPAN_USER_SHIFT);
229 }
230 } else {
231 editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
232 }
233 }
234
235 private static
236 @ColorInt
237 int transformColor(@ColorInt int c) {
238 return Color.argb(Math.round(Color.alpha(c) * 0.45f), Color.red(c), Color.green(c), Color.blue(c));
239 }
240
241 private static int indexOfIgnoreCase(final String haystack, final String needle, final int start) {
242 if (haystack == null || needle == null) {
243 return -1;
244 }
245 final int endLimit = haystack.length() - needle.length() + 1;
246 if (start > endLimit) {
247 return -1;
248 }
249 if (needle.length() == 0) {
250 return start;
251 }
252 for (int i = start; i < endLimit; i++) {
253 if (haystack.regionMatches(true, i, needle, 0, needle.length())) {
254 return i;
255 }
256 }
257 return -1;
258 }
259
260 public static class MessageEditorStyler implements TextWatcher {
261
262 private final EditText mEditText;
263 private final MessageAdapter mAdapter;
264
265 public MessageEditorStyler(EditText editText, MessageAdapter adapter) {
266 this.mEditText = editText;
267 this.mAdapter = adapter;
268 }
269
270 @Override
271 public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
272
273 }
274
275 @Override
276 public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
277
278 }
279
280 @Override
281 public void afterTextChanged(Editable editable) {
282 clear(editable);
283 final var p = PreferenceManager.getDefaultSharedPreferences(mEditText.getContext());
284 if (!p.getBoolean("compose_rich_text", mEditText.getContext().getResources().getBoolean(R.bool.compose_rich_text))) return;
285 for (final var span : editable.getSpans(0, editable.length() - 1, QuoteSpan.class)) {
286 editable.removeSpan(span);
287 }
288 format(editable, mEditText.getCurrentTextColor(), true);
289 mAdapter.handleTextQuotes(mEditText, editable, false);
290 }
291 }
292}