/*
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 1999 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution, if
 *    any, must include the following acknowlegement:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 *
 * 4. The names "The Jakarta Project", "Ant", and "Apache Software
 *    Foundation" must not be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

package org.apache.tools.ant.taskdefs.optional;

import org.apache.tools.ant.* ;
import org.apache.tools.ant.types.FileSet ;
import org.apache.tools.ant.taskdefs.CallTarget ;
import org.apache.tools.ant.taskdefs.Property ;

import java.util.Vector ;
import java.util.Hashtable ;
import java.util.Enumeration ;

/**
 * Call a target foreach entry in a set of parameters
 *
 *  <pre>
 *    <target name="target1">
 *      <foreach target="target2">
 *        <param name="param1">
 *            <fileset refid="fset1"/>
 *        </param>
 *        <param name="param2">
 *          <item value="jar" />
 *          <item value="zip" />
 *        </param>
 *       </foreach>
 *    </target>
 *
 *    <target name="target2">
 *      <echo message="prop is ${param1}.${param2}" />
 *    </target>
 * </pre>
 *
 * <br>
 * Really this just a wrapper around "AntCall"
 *
 * @author <a href="mailto:tpv@spamcop.net">Tim Vernum</a> 
 */
public class ForeachTask extends Task {

    /** 
     * Inner class stores <item>s with <param> lists
     */
    public class ParamItem {

        private String value ;

        public void setValue( String value ) {
            this.value = value ;
        }
       
        public String getValue() {
            return this.value ;
        }
       
    }

    /** 
     * Inner class stores sets of <param>s.
     * It can hold <fileset>s or <item>s or both.
     */
    public class ParamSet {

        private Vector      filesets ;
        private Vector    items ;
        private String      name ;

        public ParamSet() {
            filesets = new Vector() ;
            items    = new Vector() ;
        }
   
        public void addFileset( FileSet fileset ) {
            filesets.addElement( fileset ) ;
        }

        public ParamItem createItem() {
            ParamItem item = new ParamItem() ;
            items.addElement( item ) ;
            return item ;
        }
         
        public void setName( String name ) {
            this.name = name ;
        }

        public String getName( ) {
            return name ;
        }

        public Enumeration getValues( Project project ) {

            /* As an arbitrary rule, this will return filesets first,
               and then <item>s. The ordering of the buildfile is
               not guaranteed. */
            Vector values = new Vector() ;

            Enumeration enum = filesets.elements() ;
            while( enum.hasMoreElements() ) {

                FileSet fileSet = (FileSet)enum.nextElement() ;
                DirectoryScanner scanner = fileSet.getDirectoryScanner(project) ;
                String[] files = scanner.getIncludedFiles() ;

                for( int i=0 ; i< files.length ; i++ ) {
                    values.addElement( files[i] ) ;
                }
            }

            enum = items.elements() ;
            while( enum.hasMoreElements() ) {

                ParamItem item = (ParamItem)enum.nextElement() ;
                values.addElement( item.getValue() ) ;
            }
            
            return values.elements() ;
        }

    }

    private String    subTarget;
    private Vector    params ;
    private Hashtable properties ;

    public ForeachTask( ) {
        params = new Vector() ;
        properties  = new Hashtable() ;
    }

    public void init() {
    }

    private void buildProperty( String propName, String propValue ) {
        properties.put(propName,propValue) ;
    }

    private void executeTarget() {

        /* The "callee" has to be created each time in order to make
           the properties mutable. */
        CallTarget callee;
        callee = (CallTarget) project.createTask("antcall");
        callee.init() ;

        callee.setTarget(subTarget);

        Enumeration keys = properties.keys();
        while( keys.hasMoreElements() ) {

            String key = (String)keys.nextElement() ;
            String val = (String)properties.get(key) ;

            Property prop = callee.createParam() ;
            prop.setName( key ) ;
            prop.setValue( val ) ;
        }

        callee.execute();
    }

    /** This method is used to recursively iterate through
      * each parameter set.
      * It ends up being something like:
      * <pre>
      *    for( i=0; i< params[0].size ; i++ )
      *       for( j=0; j < params[1].size ; j++ )
      *          for( k=0; k < params[2].size ; k++ )
      *             executeTarget( params[0][i], params[1][j] , params[2][k] ) ;
      * </pre>
      */ 
    private void executeParameters( int paramNumber ) {

        if( paramNumber == params.size() ) {

            executeTarget() ;
        }
        else {
            ParamSet paramSet = (ParamSet)params.elementAt(paramNumber) ;

            Enumeration values = paramSet.getValues(project) ;
            while( values.hasMoreElements() ) { 

                String val = (String)values.nextElement() ;
                buildProperty( paramSet.getName(), val ) ;

                executeParameters( paramNumber+1 ) ;
            }
        }
    }

    public void execute() {
        
        if (subTarget == null) {
            throw new BuildException("Attribute target is required.", 
                                     location);
        }
        
        executeParameters(0) ;
    }

    public ParamSet createParam() {
        ParamSet param = new ParamSet() ;
        params.addElement( param ) ;
        return param ;
    }

    public void setTarget(String target) {
        subTarget = target;
    }
}