<?php
/*
 * igitigit - Web frontend for Git repositories
 * Copyright (C) 2011  Klaus Reimer <hide@address.com>
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
 * Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

namespace igitigit;

/**
 * A system directory.
 *
 * @author Klaus Reimer <hide@address.com>
 */
class SystemDirectory implements Directory, SystemObject
{
    /** The path (relative to REPOS, empty if root directory). */
    private $path;
    
    /** The directory name. */
    private $name;
    
    /** The parent file. NULL when this is the root directory. */
    private $parent;
    
    /**
     * Constructs a new directory.
     *
     * @param string $name
     *             Directory name.
     * @param Directory $parent
     *             Optional parent file. If not specified then this 
     *             directory is the root directory.
     */    
    public function __construct($name, Directory $parent = NULL)
    {
        $this->name = $name;
        $this->parent = $parent;
        if ($parent)
        {
            $parentPath = $this->parent->getPath();
            $this->path = $parentPath;
            if ($parentPath && $name) $this->path .= "/";
            $this->path .= $name;
        }
        else
            $this->path = "";
    }
    
    /**
     * @see Object#getName()
     *
     * @return string
     */
    public function getName()
    {
        return $this->name;
    }
    
    /**
     * @see Object#getPath()
     *
     * @return string
     */
    public function getPath()
    {
        return $this->path;
    }
    
    /**
     * @see Object#getMode()
     *
     * @return int
     */
    public function getMode()
    {
        $stats = stat($this->getAbsPath());
        return $stats["mode"];
    }

    /**
     * @see Object#getUrl()
     *
     * @return string
     */    
    public function getUrl()
    {
        $path = $this->getPath();
        return CONTROLLER . ($path ? "/$path" : "");
    }
    
    /**
     * @see Object#getType()
     *
     * @return string
     */
    public function getType()
    {
        return Object::TYPE_SYSTEM_DIR;
    }

    /**
     * @see Object#getLastModified()
     * 
     * @return int
     */
    public function getLastModified()
    {
        return filemtime($this->getAbsPath());
    }

    /**
     * @see SystemObject#getAbsPath()
     *
     * @return string
     */    
    public function getAbsPath()
    {
        $path = $this->getPath();
        return REPOS . ($path ? ("/" . $this->getPath()) : "");
    }
    
    /**
     * @see File#getBreadcrumbs()
     * 
     * @return Breadcrumb[]
     */
    public function getBreadcrumbs()
    {
        $breadcrumbs = array();
        $current = $this;
        while ($current)
        {
            array_unshift($breadcrumbs, new Breadcrumb($current->getName(),
                $current->getUrl(), $current == $this));
            $current = $current->getParent();
        }
        return $breadcrumbs;
    }

    /**
     * @see Directory#getParent()
     *
     * @return Directory
     */
    public function getParent()
    {
        return $this->parent;
    }    
    
    /**
     * @see Directory#isRoot()
     *
     * @return boolean
     */
    public function isRoot()
    {
        return $this->parent == NULL;
    }

    /**
     * @see Directory#getObject()
     *
     * @param string $name
     * @return Object
     */
    public function getObject($name)
    {
        // When no name of "." was specified as name then return this
        // directory
        if (!$name || $name == ".") return $this;
        
        // If ".." was specified as name then return the parent directory
        // (Or NULL if no parent is present)
        if ($name == "..") return $this->parent;
            
        // Determine absolute path of the file.
        $absPath = $this->getAbsPath() . "/" . $name;
        
        // Determine type of file (and check if it exists at all).
        if (!file_exists($absPath))
            $object = NULL;
        else if (GitRepository::isGitRepository($absPath))
            $object = new GitRepository($name, $this);
        else if (is_dir($absPath))
            $object = new SystemDirectory($name, $this);
        else
            $object = new SystemFile($name, $this);
        return $object;
    }
    
    /**
     * @see Directory#getObjects()
     *
     * @return Object[]
     */
    public function getObjects()
    {
        $objects = array();
        $dir = opendir($this->getAbsPath());
        while ($name = readdir($dir))
        {
            // Ignore current and parent directory
            if ($name == "." || $name == "..") continue;

            $objects[] = $this->getObject($name);                        
        }
        usort($objects, array($this, "compareObjects"));
        return $objects;
    }
    
    /**
     * Compare method to sort an object array by type and name.
     *
     * TODO This is the same as in GitDirectory. Should move to a common
     * place.
     *
     * @param Object $a
     *            First object to compare.
     * @param Object $b
     *            Second object to compare.
     * @return int
     *            The comparison result.
     */
    private function compareObjects($a, $b)
    {
        $r = strcmp($a->getType(), $b->getType());
        if (!$r) $r = strcmp($a->getName(), $b->getName());
        return $r;
    }
}