<?php
/**
 * Bootstrap for serving all common framework functionality.
 *
 * @package system
 * @author Michael Beers <[email protected]>
 * @copyright (c) 2012, Michael Beers | Online Media en Design
 */

//Set the namespace
namespace PhpBakery;

/**
 * Bootstrap for serving all common framework functionality.
 *
 * Note: Do not use this class directly. Instead use its child class {@link PhpBakery}
 * where you can customize all methods.
 *
 * @package system
 * @author Michael Beers <[email protected]>
 * @copyright (c) 2012, Michael Beers | Online Media en Design
 * @todo logger methods
 */
class Bootstrap
{
    /**
     * Class map used to load all framework functionalities very fast.
     *
     * Format: Class name => File path
     *
     * @var array
     */
    public static $coreClassMap = array(
        'PhpBakery\Exception' => 'Exception.php',
        'PhpBakery\Web' => 'Web.php',
    );

    /**
     * Class map used to load other functionalities very fast.
     *
     * Format: Class name => File path
     *
     * @var array
     */
    public static $classMap = array();

    /**
     * Alias paths used to shorten all paths.
     *
     * Format: Alias => Path
     *
     * @var array
     */
    public static $aliases = array();

    /**
     * Class map used to check what resources are already loaded.
     *
     * @var array
     */
    public static $resources = array();

    /**
     * Include paths to search in for files
     *
     * @var array
     */
    public static $paths = array();

    /**
     * Whether to rely on the PHP include paths at the autoloader.
     *
     * Note: You may set this to false if your hosting environment does not support this.
     *
     * @var boolean
     */
    private static $_enableIncludePaths = TRUE;

    /**
     * Instance of the registered application.
     *
     * @var object
     */
    private static $_app;

    /**
     * Instance of the registered logger.
     *
     * @var object
     */
    private static $_logger;

    /* Constructor and class helpers.
    ===================================================== */

    /**
     * Constructor.
     */
    public function __construct()
    {
        //Set default aliases
        self::$aliases['system'] = SYS_PATH;

        //Register the autoloader
        spl_autoload_register( array($this, 'autoloader') );
    }

    /**
     * Creates a web-based application instance.
     *
     * Note: This is a function shortner for registerApplication().
     *
     * @param mixed $params Application configurations.
     * @return object
     */
    public static function runWebApplication($params = NULL)
    {
        return self::registerApplication('PhpBakery\Web', $params);
    }

    /**
     * Creates a console-based application instance.
     *
     * Note: This is a function shortner for registerApplication().
     *
     * @param mixed $params Application configurations.
     * @return object
     */
    public static function runConsoleApplication($params = NULL)
    {
        return self::registerApplication('PhpBakery\Console', $params);
    }

    /**
     * Returns the registered application instance.
     *
     * Note: This is function shortner for getApplication().
     *
     * @return object
     */
    public static function app()
    {
        return self::getApplication();
    }

    /* Application methods
    ===================================================== */

    /**
     * Creates a new application instance.
     *
     * @param string $className Class name of the application.
     * @param mixed $params Application configurations.
     * @return object
     */
    public static function registerApplication($className, $params = NULL)
    {
        return new $className($params);
    }

    /**
     * Returns the registered application instance.
     *
     * @return object
     */
    public static function getApplication()
    {
        return self::$_app;
    }

    /**
     * Set the application instance.
     *
     * Note: If the parameter is null, the existing application
     * will be removed.
     *
     * @param object $obj Application instance.
     */
    public static function setApplication($obj)
    {
        if (self::$_app === NULL || $obj === NULL)
        {
            self::$_app = $obj;
        }
        else
        {
            //Throw exception
            Throw new PhpBakery\Exception('Application instance can only be created once.');
        }
    }

    /* Autoloader methods
    ===================================================== */

    /**
     * Register a new class autoloader.
     *
     * @param mixed $callback Valid php callback (function name or array)
     * @param boolean $append Whether to append the new autoloader after the default autoloader.
     */
    public static function registerAutoloader($callback, $append = FALSE)
    {
        if ($append)
        {
            self::$_enableIncludePaths = FALSE;
            spl_autoload_register($callback);
        }
        else
        {
            spl_autoload_unregister( array($this, 'autoloader') );
            spl_autoload_register($callback);
            spl_autoload_register( array($this, 'autoloader') );
        }
    }

    /**
     * Class autoloader.
     *
     * Note: This method provided to be invoked within an __autoload() magic method.
     *
     * @param string $className Class name to be loaded.
     * @return boolean
     */
    public static function autoloader($className)
    {
        if (isset(self::$coreClassMap[$className]))
        {
            //Get class from the core class map.
            include(SYS_PATH . self::$coreClassMap[$className]);
        }
        else if (isset(self::$classMap[$className]))
        {
            //Get class from the normal class map.
            include(self::$classMap[$className]);
        }
        else
        {
            //
            // Dont know how to do this for now, first make the core classes etc.
            // This function is not needed then.
            //
        }

        return TRUE;
    }

    /* Resource methods
    ===================================================== */

    /**
     * Creates an new object an initialize it based on the given configurations.
     *
     * @param mixed $params Resource configurations. (String or Array)
     * @return object
     */
    public static function registerResource($params)
    {
        //Format parameters
        if (is_string($params))
        {
            $class = $params;
            $params = array();
        }
        else if (isset($params['class']))
        {
            $class = $params['class'];
            unset($params['class']);
        }
        else
        {
            //Throw exception
            Throw new PhpBakery\Exception('Resource configurations must contain a string or array with the key "class".');
        }

        //Check whether a class exists else import
        if (!class_exists($class, TRUE))
        {
            self::importResource($class, TRUE);
        }

        //Register the component self
        if ( func_num_args() > 1 )
        {
            $args = func_get_args();
            unset($args[0]);

            $resource_reflection = new ReflectionClass($class);
            $resource = call_user_func_array(array($resource_reflection, 'newInstance'), $args);
        }
        else
        {
            $resource = new $class();
        }

        return $resource;
    }

    /**
     * Import a resource class or directory.
     *
     * @param string $alias Alias path to the file
     * @param boolean $force Whether to include the file immediately.
     * @return string
     */
    public static function importResource($alias, $force = FALSE)
    {
        //
        // Dont know how to do this for now, first make the core classes etc.
        // This function is not needed then.
        //
    }

    /**
     * Returns a path by the given alias.
     *
     * @param string $alias Alias from the path.
     * @return mixed
     */
    public static function getAlias($alias)
    {
        if (isset(self::$aliases[$alias]))
        {
            //Get alias from alias cache
            return self::$aliases[$alias];
        }
        else if ( ($pos = strpos($alias, '.')) !== FALSE )
        {
            //Check whether a alias is having a root to return
            $root_alias = substr($alias, 0, $pos);

            if (isset(self::$aliases[$root_alias]))
            {
                //Get root alias from alias cache
                return self::$aliases[$root_alias] = rtrim(self::$aliases[$root_alias] . DS . str_replace('.', DS, substr($alias, $pos+1)), '*', DS);
            }

            //
            // Other options can be placed here like finding modules etc.
            //

        }

        return FALSE;
    }

    /**
     * Set a new alias path.
     *
     * Note: This method checks the existing path and normalizes it.
     *
     * @param string $alias Alias from the path.
     * @param string $path Path corresponding to the alias.
     */
    public static function setAlias($alias, $path = NULL)
    {
        if (empty($path))
        {
            unset(self::$aliases[$alias]);
        }
        else
        {
            self::$aliases[$alias] = ltrim($path, '\\/');
        }
    }

    /* Logging methods
    ===================================================== */

}