<?php
/**
 * Global Autoload class.
 *
 * @author Tarmo Lehtpuu <tarmo.lehtpuu@delfi.ee>
 * @author Tanel Suurhans <tanel.suurhans@delfi.ee>
 * @author Elan Ruusamäe <glen@delfi.ee>
 *
 * @package autoload
 */
class PHP_Autoload {

	private static $excludes = array('.', '..', '.svn', 'CVS', 'data', 'cake', 'propel', 'phing', 'geshi', 'adodb');
	private static $classes;
	private static $scandirs = array();

	/**
	 * array of directories already scanned
	 */
	private static $dirs = array();

	public static function autoload($className) {
		if (class_exists($className, false) || interface_exists($className, false)) {
			return true;
		}

		// Zend framework -- we can optimize
		if (strpos($className, 'Zend') === 0){
			require_once str_replace('_', '/', $className) . '.php';
			return true;
		}

		// Smarty
		if ($className === 'Smarty') {
			require_once 'Smarty/Smarty.class.php';
			return true;
		}

		if (!is_array(self::$classes)) {
			self::$classes = array();

			// scan frameworks dir
			foreach (explode(PATH_SEPARATOR, get_include_path()) as $path) {
				if ($path == '.') {
					continue;
				}
				if ($path == PEAR_INSTALL_DIR) {
					self::scan($path, true);
				} else {
					self::scan($path);
				}
			}

			// scan additional project dirs
			if (!empty(self::$scandirs)) {
				foreach (self::$scandirs as $path) {
					self::scan($path);
				}
			}
		}

		// the rest
		if (array_key_exists($className, self::$classes)) {
			require_once self::$classes[$className];
			return true;
		}
	}

	/**
	 * Return scanned class => path mappings
	 */
	public static function get_classmap() {
		return self::$classes;
	}

	/**
	 * Add project path to scan for additional classes.
	 */
	public static function add_path($dir) {
		self::$scandirs = array_merge(self::$scandirs, array($dir));
	}

	private static function scan($path, $pear = false, $subdir = null) {
		$scandir = $subdir ? $path . DIRECTORY_SEPARATOR . $subdir : $path;

		if (array_key_exists($scandir, self::$dirs)) {
			return;
		}
		self::$dirs[$scandir] = true;

		$dh = opendir($scandir);
		while (($file = readdir($dh)) !== false) {
			// omit exclusions
			if (array_search($file, self::$excludes) !== false) {
				continue;
			}

			// exclude hidden paths
			if ($file[0] == '.') {
				continue;
			}

			// recurse
			if (is_dir($scandir. DIRECTORY_SEPARATOR . $file)) {
				self::scan($path, $pear, $subdir ? $subdir . DIRECTORY_SEPARATOR . $file : $file);
				continue;
			}

			// skip without .php extension
			if (substr($file, -4) != '.php') {
				continue;
			}
			$class = substr($file, 0, -4);

			// rewrite class.CLASSNAME.php
			if (substr($class, 0, 6) === 'class.') {
				$class = substr($class, 6);
			}

			if (strchr($class, '.') !== false || strchr($class, '-') !== false) {
				// TODO: class name can't contain those chars either: .!@#$%^&*+=-[](){}
				continue;
			}
			if ($pear && $subdir) {
				$pearclass = str_replace('/', '_', $subdir . DIRECTORY_SEPARATOR . $class);
				self::$classes[$pearclass] = $scandir . DIRECTORY_SEPARATOR . $file;
			} else {
				self::$classes[$class] = $scandir . DIRECTORY_SEPARATOR . $file;
				// XXX: Eventum
				$parts = array();
				foreach (split('_', $class) as $part) {
					$parts[] = ucfirst($part);
				}
				$class = join('_', $parts);
				self::$classes[$class] = $scandir . DIRECTORY_SEPARATOR . $file;
				// XXX: Eventum: SCM class
				self::$classes[strtoupper($class)] = $f = $scandir . DIRECTORY_SEPARATOR . $file;
			}
		}
		closedir($dh);
	}
}

spl_autoload_register(array('PHP_Autoload', 'autoload'));