001 /*
002 * Copyright (C) 2010 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.term;
021
022 import org.crsh.term.console.Console;
023 import org.crsh.term.console.ViewWriter;
024 import org.crsh.term.spi.TermIO;
025 import org.slf4j.Logger;
026 import org.slf4j.LoggerFactory;
027
028 import java.io.IOException;
029 import java.util.LinkedList;
030
031 /**
032 * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
033 * @version $Revision$
034 */
035 public class BaseTerm implements Term {
036
037 /** . */
038 private final Logger log = LoggerFactory.getLogger(BaseTerm.class);
039
040 /** . */
041 private final LinkedList<CharSequence> history;
042
043 /** . */
044 private CharSequence historyBuffer;
045
046 /** . */
047 private int historyCursor;
048
049 /** . */
050 private final TermIO io;
051
052 /** . */
053 private final Console console;
054
055 public BaseTerm(final TermIO io) {
056 this.history = new LinkedList<CharSequence>();
057 this.historyBuffer = null;
058 this.historyCursor = -1;
059 this.io = io;
060 this.console = new Console(new ViewWriter() {
061
062 @Override
063 protected void flush() throws IOException {
064 io.flush();
065 }
066
067 @Override
068 protected void writeCRLF() throws IOException {
069 io.writeCRLF();
070 }
071
072 @Override
073 protected void write(CharSequence s) throws IOException {
074 io.write(s.toString());
075 }
076
077 @Override
078 protected void write(char c) throws IOException {
079 io.write(c);
080 }
081
082 @Override
083 protected void writeDel() throws IOException {
084 io.writeDel();
085 }
086
087 @Override
088 protected boolean writeMoveLeft() throws IOException {
089 return io.moveLeft();
090 }
091
092 @Override
093 protected boolean writeMoveRight(char c) throws IOException {
094 return io.moveRight(c);
095 }
096 });
097 }
098
099 public int getWidth() {
100 return io.getWidth();
101 }
102
103 public void setEcho(boolean echo) {
104 console.setEchoing(echo);
105 }
106
107 public TermEvent read() throws IOException {
108
109 //
110 while (true) {
111 int code = io.read();
112 CodeType type = io.decode(code);
113 switch (type) {
114 case CLOSE:
115 return new TermEvent.Close();
116 case BACKSPACE:
117 console.getViewReader().del();
118 break;
119 case UP:
120 case DOWN:
121 int nextHistoryCursor = historyCursor + (type == CodeType.UP ? + 1 : -1);
122 if (nextHistoryCursor >= -1 && nextHistoryCursor < history.size()) {
123 CharSequence s = nextHistoryCursor == -1 ? historyBuffer : history.get(nextHistoryCursor);
124 CharSequence t = console.getViewReader().replace(s);
125 if (historyCursor == -1) {
126 historyBuffer = t;
127 }
128 if (nextHistoryCursor == -1) {
129 historyBuffer = null;
130 }
131 historyCursor = nextHistoryCursor;
132 }
133 break;
134 case RIGHT:
135 console.getViewReader().moveRight();
136 break;
137 case LEFT:
138 console.getViewReader().moveLeft();
139 break;
140 case BREAK:
141 log.debug("Want to cancel evaluation");
142 console.clearBuffer();
143 return new TermEvent.Break();
144 case CHAR:
145 if (code >= 0 && code < 128) {
146 console.getViewReader().write((char)code);
147 } else {
148 log.debug("Unhandled char " + code);
149 }
150 break;
151 case TAB:
152 log.debug("Tab");
153 return new TermEvent.Complete(console.getBufferToCursor());
154 }
155
156 //
157 if (console.getReader().hasNext()) {
158 historyCursor = -1;
159 historyBuffer = null;
160 CharSequence input = console.getReader().next();
161 return new TermEvent.ReadLine(input);
162 }
163 }
164 }
165
166 public void bufferInsert(CharSequence msg) throws IOException {
167 console.getViewReader().write(msg);
168 }
169
170 public void addToHistory(CharSequence line) {
171 history.addFirst(line);
172 }
173
174 public CharSequence getBuffer() {
175 return console.getBufferToCursor();
176 }
177
178 public void close() {
179 try {
180 log.debug("Closing connection");
181 io.flush();
182 io.close();
183 } catch (IOException e) {
184 log.debug("Exception thrown during term close()", e);
185 }
186 }
187
188 public void write(CharSequence msg) throws IOException {
189 console.getWriter().write(msg);
190 }
191 }