/*
    * Copyright (C) 2007-2012 Argeo GmbH
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *         http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.argeo.slc.lib.linux;
  
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.commons.io.FilenameUtils;
  import org.apache.commons.io.IOUtils;
  import org.argeo.slc.SlcException;
  import org.argeo.slc.core.execution.tasks.SystemCall;
  import org.springframework.beans.factory.InitializingBean;
  import org.springframework.core.io.Resource;
  
  /** Call to the interpreter of a script language. */
  public class ScriptCall extends SystemCall implements InitializingBean {
  	private Resource script;
  	private List<Object> scriptArgs = new ArrayList<Object>();
  
  	private Boolean localScriptCopy = false;
  
  	/** For use in Spring. */
  	public ScriptCall() {
  		super();
  	}
  
  	/** For use in code ({@link #init()} is called). */
  	public ScriptCall(Resource script) {
  		this.script = script;
  		init();
  	}
  
  	public void init() {
  		initInterpreter();
  		for (Object obj : scriptArgs) {
  			arg(obj.toString());
  		}
  	}
  
  	public void afterPropertiesSet() throws Exception {
  		init();
  	}
  
  	protected void initInterpreter() {
  		String ext = FilenameUtils.getExtension(script.getFilename());
  
  		if (localScriptCopy) {
  			File scriptFile = copyScript();
  			if ("sh".equals(ext))
  				arg("/bin/sh").arg(scriptFile.getAbsolutePath());
  			else if ("pl".equals(ext))
  				arg("/usr/bin/perl").arg(scriptFile.getAbsolutePath());
  			else if ("py".equals(ext))
  				arg("/usr/bin/python").arg(scriptFile.getAbsolutePath());
  			else
  				throw new SlcException(
  						"Cannot initialize script intepreter for " + script);
  		} else {
  			setStdInFile(script);
  			if ("sh".equals(ext))
  				arg("/bin/sh").arg("-s");
  			else if ("pl".equals(ext))
  				arg("/usr/bin/perl").arg("/dev/stdin");
  			else if ("py".equals(ext))
  				arg("/usr/bin/python").arg("-");
  			else
  				throw new SlcException(
  						"Cannot initialize script intepreter for " + script);
  		}
  	}
  
  	private File copyScript() {
  		InputStream in = null;
  		OutputStream out = null;
  		try {
  			File scriptFile = File.createTempFile("script", ".sh");
  			scriptFile.deleteOnExit();
  			in = script.getInputStream();
  			out = new FileOutputStream(scriptFile);
  			IOUtils.copy(in, out);
  			return scriptFile;
  		} catch (Exception e) {
 			throw new SlcException("Cannot copy " + script, e);
 		} finally {
 			IOUtils.closeQuietly(in);
 			IOUtils.closeQuietly(out);
 		}
 	}
 
 	public void setScript(Resource script) {
 		this.script = script;
 	}
 
 	public void setScriptArgs(List<Object> scriptArgs) {
 		this.scriptArgs = scriptArgs;
 	}
 
 	public void setLocalScriptCopy(Boolean localScriptCopy) {
 		this.localScriptCopy = localScriptCopy;
 	}
 
 }