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