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 org.crsh.shell.ScreenContext;
023
024 import java.io.IOException;
025 import java.util.LinkedList;
026
027 public class RenderAppendable implements Appendable, ScreenContext<Chunk> {
028
029 /** . */
030 private final ScreenContext<Chunk> context;
031
032 /** . */
033 private LinkedList<Style.Composite> stack;
034
035 public RenderAppendable(ScreenContext<Chunk> context) {
036 this.context = context;
037 }
038
039 private void safeAppend(Chunk chunk) {
040 try {
041 context.provide(chunk);
042 }
043 catch (java.io.IOException e) {
044 // e.printStackTrace();
045 }
046 }
047
048 public Class<Chunk> getConsumedType() {
049 return Chunk.class;
050 }
051
052 public int getWidth() {
053 return context.getWidth();
054 }
055
056 public int getHeight() {
057 return context.getHeight();
058 }
059
060 public void provide(Chunk element) throws IOException {
061 context.provide(element);
062 }
063
064 public void flush() throws IOException {
065 context.flush();
066 }
067
068 public RenderAppendable append(CharSequence csq) {
069 safeAppend(Text.create(csq));
070 return this;
071 }
072
073 public void enterStyle(Style.Composite style) {
074 if (stack == null) {
075 stack = new LinkedList<Style.Composite>();
076 }
077 safeAppend(style);
078 stack.addLast(style);
079 }
080
081 public Style.Composite leaveStyle() {
082 if (stack == null || stack.isEmpty()) {
083 throw new IllegalStateException("Cannot leave non existing style");
084 }
085 Style.Composite last = stack.removeLast();
086 if (stack.size() > 0) {
087
088 // Compute merged
089 Style.Composite merged = getMerged();
090
091 // Compute diff with removed
092 Boolean bold = foo(last.getBold(), merged.getBold());
093 Boolean underline = foo(last.getUnderline(), merged.getUnderline());
094 Boolean blink = foo(last.getBlink(), merged.getBlink());
095
096 // For now we assume that black is the default background color
097 // and white is the default foreground color
098 Color fg = foo(last.getForeground(), merged.getForeground(), Color.def);
099 Color bg = foo(last.getBackground(), merged.getBackground(), Color.def);
100
101 //
102 Style.Composite bilto = Style.style(bold, underline, blink, fg, bg);
103
104 //
105 safeAppend(bilto);
106 } else {
107 safeAppend(Style.reset);
108 }
109 return last;
110 }
111
112 /**
113 * Compute the current merged style.
114 *
115 * @return the merged style
116 */
117 private Style.Composite getMerged() {
118 Style.Composite merged = Style.style();
119 for (Style s : stack) {
120 merged = (Style.Composite)merged.merge(s);
121 }
122 return merged;
123 }
124
125 private Boolean foo(Boolean last, Boolean merged) {
126 if (last != null) {
127 if (merged != null) {
128 return merged;
129 } else {
130 return !last;
131 }
132 } else {
133 return null;
134 }
135 }
136
137 private Color foo(Color last, Color merged, Color def) {
138 if (last != null) {
139 if (merged != null) {
140 return merged;
141 } else {
142 return def;
143 }
144 } else {
145 return null;
146 }
147 }
148
149 public void styleOff() {
150 if (stack != null && stack.size() > 0) {
151 safeAppend(Style.reset);
152 }
153 }
154
155 public void styleOn() {
156 if (stack != null && stack.size() > 0) {
157 safeAppend(getMerged());
158 }
159 }
160
161 public RenderAppendable append(CharSequence csq, int start, int end) {
162 safeAppend(Text.create(csq.subSequence(start, end)));
163 return this;
164 }
165
166 public RenderAppendable append(char c) {
167 safeAppend(Text.create(Character.toString(c)));
168 return this;
169 }
170 }