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