<?php

/**
 * @package KantPHP
 * @author  Zhenqiang Zhang <zhenqiang.zhang@hotmail.com>
 * @copyright (c) KantPHP Studio, All rights reserved.
 * @license http://www.opensource.org/licenses/BSD-3-Clause  The BSD 3-Clause License
 */
namespace Kant\View;

use Kant\Foundation\BaseObject;
use Kant\Helper\ArrayHelper;
use Kant\Helper\Url;
use Kant\Kant;

/**
 * AssetBundle represents a collection of asset files, such as CSS, JS, images.
 *
 * Each asset bundle has a unique name that globally identifies it among all asset bundles used in an application.
 * The name is the [fully qualified class name](http://php.net/manual/en/language.namespaces.rules.php)
 * of the class representing it.
 *
 * An asset bundle can depend on other asset bundles. When registering an asset bundle
 * with a view, all its dependent asset bundles will be automatically registered.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @since 2.0
 */
class AssetBundle extends BaseObject
{

    /**
     *
     * @var string the directory that contains the source asset files for this asset bundle.
     *      A source asset file is a file that is part of your source code repository of your Web application.
     *     
     *      You must set this property if the directory containing the source asset files is not Web accessible.
     *      By setting this property, [[AssetManager]] will publish the source asset files
     *      to a Web-accessible directory automatically when the asset bundle is registered on a page.
     *     
     *      If you do not set this property, it means the source asset files are located under [[basePath]].
     *     
     *      You can use either a directory or an alias of the directory.
     * @see $publishOptions
     */
    public $sourcePath;

    /**
     *
     * @var string the Web-accessible directory that contains the asset files in this bundle.
     *     
     *      If [[sourcePath]] is set, this property will be *overwritten* by [[AssetManager]]
     *      when it publishes the asset files from [[sourcePath]].
     *     
     *      You can use either a directory or an alias of the directory.
     */
    public $basePath;

    /**
     *
     * @var string the base URL for the relative asset files listed in [[js]] and [[css]].
     *     
     *      If [[sourcePath]] is set, this property will be *overwritten* by [[AssetManager]]
     *      when it publishes the asset files from [[sourcePath]].
     *     
     *      You can use either a URL or an alias of the URL.
     */
    public $baseUrl;

    /**
     *
     * @var array list of bundle class names that this bundle depends on.
     *     
     *      For example:
     *     
     *      ```php
     *      public $depends = [
     *      'Kant\View\KantAsset',
     *      'Kant\View\BootstrapAsset',
     *      ];
     *      ```
     */
    public $depends = [];

    /**
     *
     * @var array list of JavaScript files that this bundle contains. Each JavaScript file can be
     *      specified in one of the following formats:
     *     
     *      - an absolute URL representing an external asset. For example,
     *      `http://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js` or
     *      `//ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js`.
     *      - a relative path representing a local asset (e.g. `js/main.js`). The actual file path of a local
     *      asset can be determined by prefixing [[basePath]] to the relative path, and the actual URL
     *      of the asset can be determined by prefixing [[baseUrl]] to the relative path.
     *      - an array, with the first entry being the URL or relative path as described before, and a list of key => value pairs
     *      that will be used to overwrite [[jsOptions]] settings for this entry.
     *      This functionality is available since version 2.0.7.
     *     
     *      Note that only a forward slash "/" should be used as directory separator.
     */
    public $js = [];

    /**
     *
     * @var array list of CSS files that this bundle contains. Each CSS file can be specified
     *      in one of the three formats as explained in [[js]].
     *     
     *      Note that only a forward slash "/" should be used as directory separator.
     */
    public $css = [];

    /**
     *
     * @var array the options that will be passed to [[View::registerJsFile()]]
     *      when registering the JS files in this bundle.
     */
    public $jsOptions = [];

    /**
     *
     * @var array the options that will be passed to [[View::registerCssFile()]]
     *      when registering the CSS files in this bundle.
     */
    public $cssOptions = [];

    /**
     *
     * @var array the options to be passed to [[AssetManager::publish()]] when the asset bundle
     *      is being published. This property is used only when [[sourcePath]] is set.
     */
    public $publishOptions = [];

    /**
     * Registers this asset bundle with a view.
     * 
     * @param View $view
     *            the view to be registered with
     * @return static the registered asset bundle instance
     */
    public static function register($view)
    {
        return $view->registerAssetBundle(get_called_class());
    }

    /**
     * Initializes the bundle.
     * If you override this method, make sure you call the parent implementation in the last.
     */
    public function init()
    {
        if ($this->sourcePath !== null) {
            $this->sourcePath = rtrim(Kant::getAlias($this->sourcePath), '/\\');
        }
        if ($this->basePath !== null) {
            $this->basePath = rtrim(Kant::getAlias($this->basePath), '/\\');
        }
        if ($this->baseUrl !== null) {
            $this->baseUrl = rtrim(Kant::getAlias($this->baseUrl), '/');
        }
    }

    /**
     * Registers the CSS and JS files with the given view.
     * 
     * @param \Kant\View\View $view
     *            the view that the asset files are to be registered with.
     */
    public function registerAssetFiles($view)
    {
        $manager = $view->getAssetManager();
        foreach ($this->js as $js) {
            if (is_array($js)) {
                $file = array_shift($js);
                $options = ArrayHelper::merge($this->jsOptions, $js);
                $view->registerJsFile($manager->getAssetUrl($this, $file), $options);
            } else {
                if ($js !== null) {
                    $view->registerJsFile($manager->getAssetUrl($this, $js), $this->jsOptions);
                }
            }
        }
        foreach ($this->css as $css) {
            if (is_array($css)) {
                $file = array_shift($css);
                $options = ArrayHelper::merge($this->cssOptions, $css);
                $view->registerCssFile($manager->getAssetUrl($this, $file), $options);
            } else {
                if ($css !== null) {
                    $view->registerCssFile($manager->getAssetUrl($this, $css), $this->cssOptions);
                }
            }
        }
    }

    /**
     * Publishes the asset bundle if its source code is not under Web-accessible directory.
     * It will also try to convert non-CSS or JS files (e.g. LESS, Sass) into the corresponding
     * CSS or JS files using [[AssetManager::converter|asset converter]].
     * 
     * @param AssetManager $am
     *            the asset manager to perform the asset publishing
     */
    public function publish($am)
    {
        if ($this->sourcePath !== null && ! isset($this->basePath, $this->baseUrl)) {
            list ($this->basePath, $this->baseUrl) = $am->publish($this->sourcePath, $this->publishOptions);
        }
        
        if (isset($this->basePath, $this->baseUrl) && ($converter = $am->getConverter()) !== null) {
            foreach ($this->js as $i => $js) {
                if (is_array($js)) {
                    $file = array_shift($js);
                    if (Url::isRelative($file)) {
                        $js = ArrayHelper::merge($this->jsOptions, $js);
                        array_unshift($js, $converter->convert($file, $this->basePath));
                        $this->js[$i] = $js;
                    }
                } elseif (Url::isRelative($js)) {
                    $this->js[$i] = $converter->convert($js, $this->basePath);
                }
            }
            foreach ($this->css as $i => $css) {
                if (is_array($css)) {
                    $file = array_shift($css);
                    if (Url::isRelative($file)) {
                        $css = ArrayHelper::merge($this->cssOptions, $css);
                        array_unshift($css, $converter->convert($file, $this->basePath));
                        $this->css[$i] = $css;
                    }
                } elseif (Url::isRelative($css)) {
                    $this->css[$i] = $converter->convert($css, $this->basePath);
                }
            }
        }
    }
}
