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.support.annotation.ColorInt;
36import android.support.v4.content.ContextCompat;
37import android.text.Editable;
38import android.text.ParcelableSpan;
39import android.text.Spannable;
40import android.text.SpannableString;
41import android.text.Spanned;
42import android.text.TextWatcher;
43import android.text.style.BackgroundColorSpan;
44import android.text.style.ForegroundColorSpan;
45import android.text.style.StrikethroughSpan;
46import android.text.style.StyleSpan;
47import android.text.style.TypefaceSpan;
48import android.util.Log;
49import android.widget.EditText;
50import android.widget.TextView;
51
52import java.util.ArrayList;
53import java.util.Arrays;
54import java.util.List;
55
56import eu.siacs.conversations.Config;
57import eu.siacs.conversations.R;
58import eu.siacs.conversations.entities.Message;
59import eu.siacs.conversations.ui.text.QuoteSpan;
60
61public class StylingHelper {
62
63 private static List<? extends Class<? extends ParcelableSpan>> SPAN_CLASSES = Arrays.asList(
64 StyleSpan.class,
65 StrikethroughSpan.class,
66 TypefaceSpan.class,
67 ForegroundColorSpan.class
68 );
69
70 public static void clear(final Editable editable) {
71 final int end = editable.length() - 1;
72 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
73 for (ParcelableSpan span : editable.getSpans(0, end, clazz)) {
74 editable.removeSpan(span);
75 }
76 }
77 }
78
79 public static void format(final Editable editable, int start, int end, @ColorInt int textColor) {
80 for (ImStyleParser.Style style : ImStyleParser.parse(editable, start, end)) {
81 final int keywordLength = style.getKeyword().length();
82 editable.setSpan(createSpanForStyle(style), style.getStart() + keywordLength, style.getEnd() - keywordLength + 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
83 makeKeywordOpaque(editable, style.getStart(), style.getStart() + keywordLength, textColor);
84 makeKeywordOpaque(editable, style.getEnd() - keywordLength + 1, style.getEnd() + 1, textColor);
85 }
86 }
87
88 public static void format(final Editable editable, @ColorInt int textColor) {
89 int end = 0;
90 Message.MergeSeparator[] spans = editable.getSpans(0, editable.length() - 1, Message.MergeSeparator.class);
91 for (Message.MergeSeparator span : spans) {
92 format(editable, end, editable.getSpanStart(span), textColor);
93 end = editable.getSpanEnd(span);
94 }
95 format(editable, end, editable.length() - 1, textColor);
96 }
97
98 public static void highlight(final Context context, final Editable editable, List<String> needles, boolean dark) {
99 for (String needle : needles) {
100 if (!FtsUtils.isKeyword(needle)) {
101 highlight(context, editable, needle, dark);
102 }
103 }
104 }
105
106 public static List<String> filterHighlightedWords(List<String> terms) {
107 List<String> words = new ArrayList<>();
108 for (String term : terms) {
109 if (!FtsUtils.isKeyword(term)) {
110 StringBuilder builder = new StringBuilder();
111 for (int codepoint, i = 0; i < term.length(); i += Character.charCount(codepoint)) {
112 codepoint = term.codePointAt(i);
113 if (Character.isLetterOrDigit(codepoint)) {
114 builder.append(Character.toChars(codepoint));
115 }
116 }
117 if (builder.length() > 0) {
118 words.add(builder.toString());
119 }
120 }
121 }
122 return words;
123 }
124
125 private static void highlight(final Context context, final Editable editable, String needle, boolean dark) {
126 final int length = needle.length();
127 String string = editable.toString();
128 int start = indexOfIgnoreCase(string, needle, 0);
129 while (start != -1) {
130 int end = start + length;
131 editable.setSpan(new BackgroundColorSpan(ContextCompat.getColor(context, dark ? R.color.blue_a100 : R.color.blue_a200)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
132 editable.setSpan(new ForegroundColorSpan(ContextCompat.getColor(context, dark ? R.color.black87 : R.color.white)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
133 start = indexOfIgnoreCase(string, needle, start + length);
134 }
135
136 }
137
138 static CharSequence subSequence(CharSequence charSequence, int start, int end) {
139 if (start == 0 && charSequence.length() + 1 == end) {
140 return charSequence;
141 }
142 if (charSequence instanceof Spannable) {
143 Spannable spannable = (Spannable) charSequence;
144 Spannable sub = (Spannable) spannable.subSequence(start, end);
145 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
146 ParcelableSpan[] spannables = spannable.getSpans(start, end, clazz);
147 for (ParcelableSpan parcelableSpan : spannables) {
148 int beginSpan = spannable.getSpanStart(parcelableSpan);
149 int endSpan = spannable.getSpanEnd(parcelableSpan);
150 if (beginSpan >= start && endSpan <= end) {
151 continue;
152 }
153 sub.setSpan(clone(parcelableSpan), Math.max(beginSpan - start, 0), Math.min(sub.length() - 1, endSpan), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
154 }
155 }
156 return sub;
157 } else {
158 return charSequence.subSequence(start, end);
159 }
160 }
161
162 private static ParcelableSpan clone(ParcelableSpan span) {
163 if (span instanceof ForegroundColorSpan) {
164 return new ForegroundColorSpan(((ForegroundColorSpan) span).getForegroundColor());
165 } else if (span instanceof TypefaceSpan) {
166 return new TypefaceSpan(((TypefaceSpan) span).getFamily());
167 } else if (span instanceof StyleSpan) {
168 return new StyleSpan(((StyleSpan) span).getStyle());
169 } else if (span instanceof StrikethroughSpan) {
170 return new StrikethroughSpan();
171 } else {
172 throw new AssertionError("Unknown Span");
173 }
174 }
175
176 public static boolean isDarkText(TextView textView) {
177 int argb = textView.getCurrentTextColor();
178 return Color.red(argb) + Color.green(argb) + Color.blue(argb) == 0;
179 }
180
181 private static ParcelableSpan createSpanForStyle(ImStyleParser.Style style) {
182 switch (style.getKeyword()) {
183 case "*":
184 return new StyleSpan(Typeface.BOLD);
185 case "_":
186 return new StyleSpan(Typeface.ITALIC);
187 case "~":
188 return new StrikethroughSpan();
189 case "`":
190 case "```":
191 return new TypefaceSpan("monospace");
192 default:
193 throw new AssertionError("Unknown Style");
194 }
195 }
196
197 private static void makeKeywordOpaque(final Editable editable, int start, int end, @ColorInt int fallbackTextColor) {
198 QuoteSpan[] quoteSpans = editable.getSpans(start, end, QuoteSpan.class);
199 @ColorInt int textColor = quoteSpans.length > 0 ? quoteSpans[0].getColor() : fallbackTextColor;
200 @ColorInt int keywordColor = transformColor(textColor);
201 editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
202 }
203
204 private static
205 @ColorInt
206 int transformColor(@ColorInt int c) {
207 return Color.argb(Math.round(Color.alpha(c) * 0.45f), Color.red(c), Color.green(c), Color.blue(c));
208 }
209
210 private static int indexOfIgnoreCase(final String haystack, final String needle, final int start) {
211 if (haystack == null || needle == null) {
212 return -1;
213 }
214 final int endLimit = haystack.length() - needle.length() + 1;
215 if (start > endLimit) {
216 return -1;
217 }
218 if (needle.length() == 0) {
219 return start;
220 }
221 for (int i = start; i < endLimit; i++) {
222 if (haystack.regionMatches(true, i, needle, 0, needle.length())) {
223 return i;
224 }
225 }
226 return -1;
227 }
228
229 public static class MessageEditorStyler implements TextWatcher {
230
231 private final EditText mEditText;
232
233 public MessageEditorStyler(EditText editText) {
234 this.mEditText = editText;
235 }
236
237 @Override
238 public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
239
240 }
241
242 @Override
243 public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
244
245 }
246
247 @Override
248 public void afterTextChanged(Editable editable) {
249 clear(editable);
250 format(editable, mEditText.getCurrentTextColor());
251 }
252 }
253}