<?php

/**
 * provides {@link r3_generate_OutputManager} class
 *
 *
 * Copyright (c) 2007 Yahoo! Inc.  All rights reserved.
 * The copyrights embodied in the content of this file are licensed under the BSD
 * open source license
 *
 * @package r3
 * @subpackage generate
 */

/**
 * requires
 */
 require_once( "r3/generate/Output.php" );
 require_once( "r3/generate/FileOutput.php" );
 require_once( "r3/generate/StdoutOutput.php" );


/**
 * provides {@link r3_generate_Output} class
 *
 * @package r3
 * @subpackage generate
 */
class r3_generate_OutputManager {
    private $outputstack = array();
    private $defaultOutput;

   
    function __construct() {
        $this->setDefault( new r3_generate_FileOutput() );
    }

    function stackEmpty() {
        return ( ! count( $this->outputstack ) ); 
    }

    function setDefault( r3_generate_Output $output ) {
        $this->defaultOutput = $output;
    }

    private function current() {
        if ( $this->stackEmpty() ) {
            $this->add( $this->defaultOutput );
        }
        return $this->outputstack[ count( $this->outputstack )-1 ];
    }

    function open(  r3_generate_GenerateContext $context ) {
        $current = $this->current();
        $current->open( $context );
    }

    function output(  $txt ) {
        $current = $this->current();
        if ( ! $current->isOpen() ) {
            throw new r3_util_Exception("attempting to write to unopened Output");
        }
        $current->output( $txt );
    }

    function close(  ) {
        $current = $this->current();
        if ( $current->isOpen() ) {
            $current->close( );
        }
        array_pop( $this->outputstack );
    }

    function remove( ) {
        $this->current();
        return array_pop( $this->outputstack );
    }

    function add( r3_generate_Output $output ) {
        array_push( $this->outputstack, $output );
    }


    function clear() {
        $this->outputstack=array();
    }

    function closeAll( ) {
        while ( ! is_null( $this->close( ) ) ) {
            ;
        }
    }
}

?>