<?php
/**
* Autoload debugging
*
* The internal __autoload() function of the shell-wrapper has two hooks.
* The first is called before the include is done, the second afterwards.
*
* we use it to track the order the includes are handled. That makes it 
* easier to find implicit dependency problems.
*
* :set autoloaddebug = on
* :set autoloaddebug = off
*
* the depth functions track the recursive depth of the includes. The
* wrapper uses it to print the dots at the beginning of the line.
*/
class PHP_Shell_Extensions_AutoloadDebug implements PHP_Shell_Extension {
    /**
    * is the extenion enabled
    *
    * @var bool
    */
    protected $autoload_debug = false;

    /**
    * recursive depth of the includes
    *
    * @var int
    */
    protected $autoload_depth = 0;

    public function register() {
        $opt = PHP_Shell_Options::getInstance();
        $opt->registerOption('autoloaddebug', $this, 'optSetAutoloadDebug');
    }

    /**
    * handle the autoloaddebug flag
    *
    * @param string  
    */
    public function optSetAutoloadDebug($key, $value) {
        switch ($value) {
        case "enable":
        case "1":
        case "on":
            $this->autoload_debug = true;
            break;
        case "disable":
        case "0":
        case "off":
            $this->autoload_debug = false;
            break;
        default:
            printf(":set %s failed, unknown value. Use :set %s = (on|off)", $key, $key);
            return;
        }

    }

    /**
    * is the autoload-debug flag set ?
    *
    * @return bool true if debug is enabled
    */
    public function isAutoloadDebug() {
        return $this->autoload_debug;
    }

    /**
    * increment the depth counter
    */
    public function incAutoloadDepth() {
        return $this->autoload_depth++;
    }
    
    /**
    * decrement the depth counter
    */
    public function decAutoloadDepth() {
        return --$this->autoload_depth;
    }
}