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.SpannableString;
40import android.text.Spanned;
41import android.text.TextWatcher;
42import android.text.style.BackgroundColorSpan;
43import android.text.style.ForegroundColorSpan;
44import android.text.style.StrikethroughSpan;
45import android.text.style.StyleSpan;
46import android.text.style.TypefaceSpan;
47import android.widget.EditText;
48import android.widget.TextView;
49
50import java.util.ArrayList;
51import java.util.Arrays;
52import java.util.List;
53
54import eu.siacs.conversations.R;
55import eu.siacs.conversations.entities.Message;
56import eu.siacs.conversations.ui.text.QuoteSpan;
57
58public class StylingHelper {
59
60 private static List<? extends Class<? extends ParcelableSpan>> SPAN_CLASSES = Arrays.asList(
61 StyleSpan.class,
62 StrikethroughSpan.class,
63 TypefaceSpan.class,
64 ForegroundColorSpan.class
65 );
66
67 public static void clear(final Editable editable) {
68 final int end = editable.length() - 1;
69 for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
70 for (ParcelableSpan span : editable.getSpans(0, end, clazz)) {
71 editable.removeSpan(span);
72 }
73 }
74 }
75
76 public static void format(final Editable editable, int start, int end, @ColorInt int textColor) {
77 for (ImStyleParser.Style style : ImStyleParser.parse(editable, start, end)) {
78 final int keywordLength = style.getKeyword().length();
79 editable.setSpan(createSpanForStyle(style), style.getStart() + keywordLength, style.getEnd() - keywordLength + 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
80 makeKeywordOpaque(editable, style.getStart(), style.getStart() + keywordLength, textColor);
81 makeKeywordOpaque(editable, style.getEnd() - keywordLength + 1, style.getEnd() + 1, textColor);
82 }
83 }
84
85 public static void format(final Editable editable, @ColorInt int textColor) {
86 int end = 0;
87 Message.MergeSeparator[] spans = editable.getSpans(0, editable.length() - 1, Message.MergeSeparator.class);
88 for (Message.MergeSeparator span : spans) {
89 format(editable, end, editable.getSpanStart(span), textColor);
90 end = editable.getSpanEnd(span);
91 }
92 format(editable, end, editable.length() - 1, textColor);
93 }
94
95 public static void highlight(final Context context, final Editable editable, List<String> needles, boolean dark) {
96 for(String needle : needles) {
97 if (!FtsUtils.isKeyword(needle)) {
98 highlight(context, editable, needle, dark);
99 }
100 }
101 }
102
103 public static List<String> filterHighlightedWords(List<String> terms) {
104 List<String> words = new ArrayList<>();
105 for(String term : terms) {
106 if (!FtsUtils.isKeyword(term)) {
107 StringBuilder builder = new StringBuilder();
108 for (int codepoint, i = 0; i < term.length(); i += Character.charCount(codepoint)) {
109 codepoint = term.codePointAt(i);
110 if (Character.isLetterOrDigit(codepoint)) {
111 builder.append(Character.toChars(codepoint));
112 }
113 }
114 if (builder.length() > 0) {
115 words.add(builder.toString());
116 }
117 }
118 }
119 return words;
120 }
121
122 private static void highlight(final Context context, final Editable editable, String needle, boolean dark) {
123 final int length = needle.length();
124 String string = editable.toString();
125 int start = indexOfIgnoreCase(string, needle, 0);
126 while (start != -1) {
127 int end = start + length;
128 editable.setSpan(new BackgroundColorSpan(ContextCompat.getColor(context, dark ? R.color.blue_a100 : R.color.blue_a200)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
129 editable.setSpan(new ForegroundColorSpan(ContextCompat.getColor(context, dark ? R.color.black87 : R.color.white)), start, end, SpannableString.SPAN_EXCLUSIVE_EXCLUSIVE);
130 start = indexOfIgnoreCase(string, needle, start + length);
131 }
132
133 }
134
135 public static boolean isDarkText(TextView textView) {
136 int argb = textView.getCurrentTextColor();
137 return Color.red(argb) + Color.green(argb) + Color.blue(argb) == 0;
138 }
139
140 private static ParcelableSpan createSpanForStyle(ImStyleParser.Style style) {
141 switch (style.getKeyword()) {
142 case "*":
143 return new StyleSpan(Typeface.BOLD);
144 case "_":
145 return new StyleSpan(Typeface.ITALIC);
146 case "~":
147 return new StrikethroughSpan();
148 case "`":
149 case "```":
150 return new TypefaceSpan("monospace");
151 default:
152 throw new AssertionError("Unknown Style");
153 }
154 }
155
156 private static void makeKeywordOpaque(final Editable editable, int start, int end, @ColorInt int fallbackTextColor) {
157 QuoteSpan[] quoteSpans = editable.getSpans(start, end, QuoteSpan.class);
158 @ColorInt int textColor = quoteSpans.length > 0 ? quoteSpans[0].getColor() : fallbackTextColor;
159 @ColorInt int keywordColor = transformColor(textColor);
160 editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
161 }
162
163 private static
164 @ColorInt
165 int transformColor(@ColorInt int c) {
166 return Color.argb(Math.round(Color.alpha(c) * 0.6f), Color.red(c), Color.green(c), Color.blue(c));
167 }
168
169 private static int indexOfIgnoreCase(final String haystack, final String needle, final int start) {
170 if (haystack == null || needle == null) {
171 return -1;
172 }
173 final int endLimit = haystack.length() - needle.length() + 1;
174 if (start > endLimit) {
175 return -1;
176 }
177 if (needle.length() == 0) {
178 return start;
179 }
180 for (int i = start; i < endLimit; i++) {
181 if (haystack.regionMatches(true, i, needle, 0, needle.length())) {
182 return i;
183 }
184 }
185 return -1;
186 }
187
188 public static class MessageEditorStyler implements TextWatcher {
189
190 private final EditText mEditText;
191
192 public MessageEditorStyler(EditText editText) {
193 this.mEditText = editText;
194 }
195
196 @Override
197 public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
198
199 }
200
201 @Override
202 public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
203
204 }
205
206 @Override
207 public void afterTextChanged(Editable editable) {
208 clear(editable);
209 format(editable, mEditText.getCurrentTextColor());
210 }
211 }
212}