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 NOLINKIFY = 0xf0;
71
72 private static final List<? extends Class<? extends ParcelableSpan>> SPAN_CLASSES = Arrays.asList(
73 StyleSpan.class,
74 StrikethroughSpan.class,
75 TypefaceSpan.class,
76 ForegroundColorSpan.class,
77 RelativeSizeSpan.class
78 );
79
80 public static void clear(final Editable editable) {
81 final int end = editable.length() - 1;
82 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
83 for (ParcelableSpan span : editable.getSpans(0, end, clazz)) {
84 editable.removeSpan(span);
85 }
86 }
87 }
88
89 public static void format(final Editable editable, int start, int end, @ColorInt int textColor, final boolean composing) {
90 for (ImStyleParser.Style style : ImStyleParser.parse(editable, start, end)) {
91 final int keywordLength = style.getKeyword().length();
92 editable.setSpan(
93 createSpanForStyle(style),
94 style.getStart() + keywordLength,
95 style.getEnd() - keywordLength + 1,
96 Spanned.SPAN_EXCLUSIVE_EXCLUSIVE |
97 ("*".equals(style.getKeyword()) || "_".equals(style.getKeyword()) ? XHTML_EMPHASIS << Spanned.SPAN_USER_SHIFT : 0) |
98 ("`".equals(style.getKeyword()) || "```".equals(style.getKeyword()) ? NOLINKIFY << Spanned.SPAN_USER_SHIFT : 0)
99 );
100 makeKeywordOpaque(editable, style.getStart(), style.getStart() + keywordLength + ("```".equals(style.getKeyword()) ? 1 : 0), textColor, composing);
101 makeKeywordOpaque(editable, style.getEnd() - keywordLength + 1, style.getEnd() + 1, textColor, composing);
102 }
103 }
104
105 public static void format(final Editable editable, @ColorInt int textColor) {
106 format(editable, textColor, false);
107 }
108
109 public static void format(final Editable editable, @ColorInt int textColor, final boolean composing) {
110 int end = 0;
111 Message.MergeSeparator[] spans = editable.getSpans(0, editable.length() - 1, Message.MergeSeparator.class);
112 for (Message.MergeSeparator span : spans) {
113 format(editable, end, editable.getSpanStart(span), textColor, composing);
114 end = editable.getSpanEnd(span);
115 }
116 format(editable, end, editable.length() - 1, textColor, composing);
117 }
118
119 public static void highlight(final TextView view, final Editable editable, final List<String> needles) {
120 for (final String needle : needles) {
121 if (!FtsUtils.isKeyword(needle)) {
122 highlight(view, editable, needle);
123 }
124 }
125 }
126
127 public static List<String> filterHighlightedWords(List<String> terms) {
128 List<String> words = new ArrayList<>();
129 for (String term : terms) {
130 if (!FtsUtils.isKeyword(term)) {
131 StringBuilder builder = new StringBuilder();
132 for (int codepoint, i = 0; i < term.length(); i += Character.charCount(codepoint)) {
133 codepoint = term.codePointAt(i);
134 if (Character.isLetterOrDigit(codepoint)) {
135 builder.append(Character.toChars(codepoint));
136 } else if (builder.length() > 0) {
137 words.add(builder.toString());
138 builder.delete(0, builder.length());
139 }
140 }
141 if (builder.length() > 0) {
142 words.add(builder.toString());
143 }
144 }
145 }
146 return words;
147 }
148
149 private static void highlight(final TextView view, final Editable editable, final String needle) {
150 final int length = needle.length();
151 String string = editable.toString();
152 int start = indexOfIgnoreCase(string, needle, 0);
153 while (start != -1) {
154 int end = start + length;
155 editable.setSpan(new BackgroundColorSpan(MaterialColors.getColor(view, com.google.android.material.R.attr.colorPrimaryFixedDim)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
156 editable.setSpan(new ForegroundColorSpan(MaterialColors.getColor(view, com.google.android.material.R.attr.colorOnPrimaryFixed)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
157 start = indexOfIgnoreCase(string, needle, start + length);
158 }
159
160 }
161
162 static CharSequence subSequence(CharSequence charSequence, int start, int end) {
163 if (start == 0 && charSequence.length() + 1 == end) {
164 return charSequence;
165 }
166 if (charSequence instanceof Spannable spannable) {
167 Spannable sub = (Spannable) spannable.subSequence(start, end);
168 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
169 ParcelableSpan[] spannables = spannable.getSpans(start, end, clazz);
170 for (ParcelableSpan parcelableSpan : spannables) {
171 int beginSpan = spannable.getSpanStart(parcelableSpan);
172 int endSpan = spannable.getSpanEnd(parcelableSpan);
173 if (beginSpan >= start && endSpan <= end) {
174 continue;
175 }
176 sub.setSpan(clone(parcelableSpan), Math.max(beginSpan - start, 0), Math.min(Math.max(sub.length() - 1, 0), endSpan), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
177 }
178 }
179 return sub;
180 } else {
181 return charSequence.subSequence(start, end);
182 }
183 }
184
185 private static ParcelableSpan clone(ParcelableSpan span) {
186 if (span instanceof ForegroundColorSpan) {
187 return new ForegroundColorSpan(((ForegroundColorSpan) span).getForegroundColor());
188 } else if (span instanceof TypefaceSpan) {
189 return new TypefaceSpan(((TypefaceSpan) span).getFamily());
190 } else if (span instanceof StyleSpan) {
191 return new StyleSpan(((StyleSpan) span).getStyle());
192 } else if (span instanceof StrikethroughSpan) {
193 return new StrikethroughSpan();
194 } else {
195 throw new AssertionError("Unknown Span");
196 }
197 }
198
199 private static ParcelableSpan createSpanForStyle(final ImStyleParser.Style style) {
200 return switch (style.getKeyword()) {
201 case "*" -> new StyleSpan(Typeface.BOLD);
202 case "_" -> new StyleSpan(Typeface.ITALIC);
203 case "~" -> new StrikethroughSpan();
204 case "`", "```" -> new TypefaceSpan("monospace");
205 default -> throw new AssertionError("Unknown Style");
206 };
207 }
208
209 private static void makeKeywordOpaque(final Editable editable, int start, int end, @ColorInt int fallbackTextColor, final boolean composing) {
210 QuoteSpan[] quoteSpans = editable.getSpans(start, end, QuoteSpan.class);
211 @ColorInt int textColor = quoteSpans.length > 0 ? quoteSpans[0].getColor() : fallbackTextColor;
212 @ColorInt int keywordColor = transformColor(textColor);
213 if (composing) {
214 if (end-start > 1) {
215 editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE | XHTML_REMOVE << Spanned.SPAN_USER_SHIFT);
216 } else {
217 editable.setSpan(new RelativeSizeSpan(0), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE | XHTML_REMOVE << Spanned.SPAN_USER_SHIFT);
218 }
219 } else {
220 editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
221 }
222 }
223
224 private static
225 @ColorInt
226 int transformColor(@ColorInt int c) {
227 return Color.argb(Math.round(Color.alpha(c) * 0.45f), Color.red(c), Color.green(c), Color.blue(c));
228 }
229
230 private static int indexOfIgnoreCase(final String haystack, final String needle, final int start) {
231 if (haystack == null || needle == null) {
232 return -1;
233 }
234 final int endLimit = haystack.length() - needle.length() + 1;
235 if (start > endLimit) {
236 return -1;
237 }
238 if (needle.length() == 0) {
239 return start;
240 }
241 for (int i = start; i < endLimit; i++) {
242 if (haystack.regionMatches(true, i, needle, 0, needle.length())) {
243 return i;
244 }
245 }
246 return -1;
247 }
248
249 public static class MessageEditorStyler implements TextWatcher {
250
251 private final EditText mEditText;
252 private final MessageAdapter mAdapter;
253
254 public MessageEditorStyler(EditText editText, MessageAdapter adapter) {
255 this.mEditText = editText;
256 this.mAdapter = adapter;
257 }
258
259 @Override
260 public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
261
262 }
263
264 @Override
265 public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
266
267 }
268
269 @Override
270 public void afterTextChanged(Editable editable) {
271 clear(editable);
272 final var p = PreferenceManager.getDefaultSharedPreferences(mEditText.getContext());
273 if (!p.getBoolean("compose_rich_text", mEditText.getContext().getResources().getBoolean(R.bool.compose_rich_text))) return;
274 for (final var span : editable.getSpans(0, editable.length() - 1, QuoteSpan.class)) {
275 editable.removeSpan(span);
276 }
277 format(editable, mEditText.getCurrentTextColor(), true);
278 mAdapter.handleTextQuotes(mEditText, editable, false);
279 }
280 }
281}