001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.text;
021
022 import java.io.IOException;
023 import java.util.LinkedList;
024
025 public class RenderAppendable implements ScreenContext {
026
027 /** . */
028 private final ScreenContext context;
029
030 /** . */
031 private LinkedList<Style.Composite> stack;
032
033 public RenderAppendable(ScreenContext context) {
034 this.context = context;
035 }
036
037 @Override
038 public RenderAppendable append(CharSequence s) {
039 try {
040 context.append(s);
041 }
042 catch (java.io.IOException ignore) {
043 }
044 return this;
045 }
046
047 @Override
048 public Screenable append(char c) {
049 try {
050 context.append(c);
051 }
052 catch (java.io.IOException ignore) {
053 }
054 return this;
055 }
056
057 @Override
058 public Screenable append(CharSequence csq, int start, int end) {
059 try {
060 context.append(csq, start, end);
061 }
062 catch (java.io.IOException ignore) {
063 }
064 return this;
065 }
066
067 @Override
068 public Screenable append(Style style) {
069 try {
070 context.append(style);
071 }
072 catch (java.io.IOException ignore) {
073 }
074 return this;
075 }
076
077 @Override
078 public Screenable cls() {
079 try {
080 context.cls();
081 }
082 catch (java.io.IOException ignore) {
083 }
084 return this;
085 }
086
087 public int getWidth() {
088 // Use one less char to have a correct display on windows
089 return Math.max(0, context.getWidth() - 1);
090 }
091
092 public int getHeight() {
093 return context.getHeight();
094 }
095
096 public void flush() throws IOException {
097 context.flush();
098 }
099
100 public void enterStyle(Style.Composite style) {
101 if (stack == null) {
102 stack = new LinkedList<Style.Composite>();
103 }
104 append(style);
105 stack.addLast(style);
106 }
107
108 public Style.Composite leaveStyle() {
109 if (stack == null || stack.isEmpty()) {
110 throw new IllegalStateException("Cannot leave non existing style");
111 }
112 Style.Composite last = stack.removeLast();
113 if (stack.size() > 0) {
114
115 // Compute merged
116 Style.Composite merged = getMerged();
117
118 // Compute diff with removed
119 Boolean bold = foo(last.getBold(), merged.getBold());
120 Boolean underline = foo(last.getUnderline(), merged.getUnderline());
121 Boolean blink = foo(last.getBlink(), merged.getBlink());
122
123 // For now we assume that black is the default background color
124 // and white is the default foreground color
125 Color fg = foo(last.getForeground(), merged.getForeground(), Color.def);
126 Color bg = foo(last.getBackground(), merged.getBackground(), Color.def);
127
128 //
129 Style.Composite bilto = Style.style(bold, underline, blink, fg, bg);
130
131 //
132 append(bilto);
133 } else {
134 append(Style.reset);
135 }
136 return last;
137 }
138
139 /**
140 * Compute the current merged style.
141 *
142 * @return the merged style
143 */
144 private Style.Composite getMerged() {
145 Style.Composite merged = Style.style();
146 for (Style s : stack) {
147 merged = (Style.Composite)merged.merge(s);
148 }
149 return merged;
150 }
151
152 private Boolean foo(Boolean last, Boolean merged) {
153 if (last != null) {
154 if (merged != null) {
155 return merged;
156 } else {
157 return !last;
158 }
159 } else {
160 return null;
161 }
162 }
163
164 private Color foo(Color last, Color merged, Color def) {
165 if (last != null) {
166 if (merged != null) {
167 return merged;
168 } else {
169 return def;
170 }
171 } else {
172 return null;
173 }
174 }
175
176 public void styleOff() {
177 if (stack != null && stack.size() > 0) {
178 append(Style.reset);
179 }
180 }
181
182 public void styleOn() {
183 if (stack != null && stack.size() > 0) {
184 append(getMerged());
185 }
186 }
187 }