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
020package org.crsh.text.ui;
021
022import groovy.lang.Closure;
023import org.crsh.groovy.GroovyCommand;
024import org.crsh.shell.impl.command.AbstractInvocationContext;
025import org.crsh.shell.impl.command.spi.CommandException;
026import org.crsh.text.Screenable;
027import org.crsh.shell.impl.command.spi.CommandInvoker;
028import org.crsh.lang.impl.groovy.command.GroovyScriptCommand;
029import org.crsh.command.InvocationContext;
030import org.crsh.text.CLS;
031import org.crsh.text.LineRenderer;
032import org.crsh.text.RenderPrintWriter;
033import org.crsh.text.Renderer;
034import org.crsh.text.Style;
035
036import java.io.IOException;
037import java.util.LinkedList;
038import java.util.Map;
039
040public class EvalElement extends Element {
041
042  /** The closure to evaluate. */
043  Closure closure;
044
045  public LineRenderer renderer() {
046
047    Object owner = closure.getOwner();
048
049    //
050    final InvocationContext ctx;
051    Object cmd;
052    while (true) {
053      if (owner instanceof GroovyCommand) {
054        cmd = owner;
055        ctx = ((GroovyCommand)cmd).peekContext();
056        break;
057      } else if (owner instanceof GroovyScriptCommand) {
058        cmd = owner;
059        ctx = ((GroovyScriptCommand)cmd).peekContext();
060        break;
061      } else if (owner instanceof Closure) {
062        owner = ((Closure)owner).getOwner();
063      } else {
064        throw new UnsupportedOperationException("Cannot resolver owner " + owner + " to command");
065      }
066    }
067
068    //
069    final LinkedList<LineRenderer> renderers = new LinkedList<LineRenderer>();
070
071    //
072    final InvocationContext nested = new AbstractInvocationContext() {
073
074      /** . */
075      private LinkedList<Object> buffer = new LinkedList<Object>();
076
077      /** . */
078      private Renderer renderable;
079
080      public CommandInvoker<?, ?> resolve(String s) throws CommandException {
081        return ctx.resolve(s);
082      }
083
084      public boolean takeAlternateBuffer() {
085        return false;
086      }
087
088      public boolean releaseAlternateBuffer() {
089        return false;
090      }
091
092      public RenderPrintWriter getWriter() {
093        return ctx.getWriter();
094      }
095
096      public Map<String, Object> getSession() {
097        return ctx.getSession();
098      }
099
100      public Map<String, Object> getAttributes() {
101        return ctx.getAttributes();
102      }
103
104      public int getWidth() {
105        return ctx.getWidth();
106      }
107
108      public int getHeight() {
109        return ctx.getHeight();
110      }
111
112      public String getProperty(String propertyName) {
113        return ctx.getProperty(propertyName);
114      }
115
116      public String readLine(String msg, boolean echo) {
117        return null;
118      }
119
120      public Class getConsumedType() {
121        return Object.class;
122      }
123
124      public Screenable append(CharSequence s) throws IOException {
125        provide(s);
126        return this;
127      }
128
129      @Override
130      public Appendable append(char c) throws IOException {
131        return append(Character.toString(c));
132      }
133
134      @Override
135      public Appendable append(CharSequence csq, int start, int end) throws IOException {
136        return append(csq.subSequence(start, end));
137      }
138
139      public Screenable append(Style style) throws IOException {
140        provide(style);
141        return this;
142      }
143
144      public Screenable cls() throws IOException {
145        provide(CLS.INSTANCE);
146        return this;
147      }
148
149      public void provide(Object element) throws IOException {
150        Renderer current = Renderer.getRenderable(element.getClass());
151        if (current == null) {
152          current = Renderer.ANY;
153        }
154        if (current != null) {
155          if (renderable != null && !current.equals(renderable)) {
156            flush();
157          }
158          buffer.addLast(element);
159          renderable = current;
160        }
161      }
162
163      public void flush() throws IOException {
164        // We don't really flush, we just compute renderables from the buffer
165        if (buffer.size() > 0) {
166          LineRenderer i = renderable.renderer(buffer.iterator());
167          buffer.clear();
168          renderers.add(i);
169        }
170      }
171
172      public void close() throws IOException {
173        // Nothing to do, except maybe release resources (and also prevent to do any other operation)
174      }
175    };
176
177    if (cmd instanceof GroovyCommand) {
178      ((GroovyCommand)cmd).pushContext(nested);
179    } else {
180      ((GroovyScriptCommand)cmd).pushContext(nested);
181    }
182    try {
183      closure.call();
184    }
185    finally {
186      if (cmd instanceof GroovyCommand) {
187        ((GroovyCommand)cmd).popContext();
188      } else {
189        ((GroovyScriptCommand)cmd).popContext();
190      }
191    }
192
193    // Be sure to flush
194    try {
195      nested.flush();
196    }
197    catch (Exception e) {
198      e.printStackTrace();
199    }
200
201    //
202    return LineRenderer.vertical(renderers);
203  }
204}