Config.php

<?php
/**
 *****************************************************************************
 ** Copyright (c) 2007-2010 Jerome Poichet <jerome@frencaze.com>
 **
 ** This software is supplied to you by Jerome Poichet in consideration of 
 ** your agreement to the following terms, and your use, installation, 
 ** modification or redistribution of this software constitutes acceptance of 
 ** these terms. If you do not agree with these terms, please do not use, 
 ** install, modify or redistribute this software.
 **
 ** In consideration of your agreement to abide by the following terms, and 
 ** subject to these terms, Jerome Poichet grants you a personal, non-exclusive
 ** license, to use, reproduce, modify and redistribute the software, with or 
 ** without modifications, in source and/or binary forms; provided that if you
 ** redistribute the software in its entirety and without modifications, you 
 ** must retain this notice and the following text and disclaimers in all such 
 ** redistributions of the software, and that in all cases attribution of 
 ** Jerome Poichet as the original author of the source code shall be included
 ** in all such resulting software products or distributions.
 **
 ** Neither the name, trademarks, service marks or logos of Jerome Poichet may
 ** be used to endorse or promote products derived from the software without 
 ** specific prior written permission from Jerome Poichet. Except as expressly
 ** stated in this notice, no other rights or licenses, express or implied, are
 ** granted by Jerome Poichet herein, including but not limited to any patent
 ** rights that may be infringed by your derivative works or by other works in
 ** which the software may be incorporated.
 ** 
 ** The software is provided by Jerome Poichet on an "AS IS" basis. 
 ** JEROME POICHET MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT 
 ** LIMITATION THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND 
 ** FITNESS FOR A PARTICULAR PURPOSE, REGARDING THE SOFTWARE OR ITS USE AND 
 ** OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.
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 ** IN NO EVENT SHALL JEROME POICHET BE LIABLE FOR ANY SPECIAL, INDIRECT, 
 ** INCIDENTAL OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
 ** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 ** OR BUSINESS INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION,
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 *****************************************************************************
 **/

class Config 
{
    var $sName;
    var $oConfig;

    public static $_configs = array();

    private function __construct($name)
    {
        global $aAppConfig;
        $this->sName = $name;

        $sClass = basename($name).'Config';
        $sAltClass = $sClass;
        $sPath = 'app/config/'.$name.'Config.php';
        $sAltPath = $sPath;

        if ($aAppConfig['TARGET']) {
            $sClass = basename($name).ucfirst(strtolower($aAppConfig['TARGET'])).'Config';
            $sPath  = 'app/config/';
            $sPath .= $aAppConfig['TARGET'].'/';
            $sPath .= dirname($name).'/'.$sClass.'.php';
        }
        if (!file_exists($sPath)) {
            if ($sAltPath && !file_exists($sAltPath)) {
                throw new Exception('Config: '.$name.' not found');
            } else {
                $sClass = $sAltClass;
                include_once $sAltPath;
            }
        } else {
            include_once $sPath;
        }

        $this->oConfig = new $sClass();
    }

    public function get($key)
    {
        return $this->oConfig->$key;
    }

    public static function get_config($name)
    {
        if (!Config::$_configs[$name]) {
            Config::$_configs[$name] = new Config($name);
        }
        return Config::$_configs[$name];
    }

}