boilerplate-plugin/Plugin.php

<?php
/*
 * Copyright 2014 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @file The main file of Mibew:Boilerplate plugin.
 *
 * Plugin's class name, its namespace and file path must follow special naming
 * conventions. The name of the main plugin class should match pattern:
 * "\<Vendor Name>\Mibew\Plugin\<Plugin name>\Plugin". It should be placed in
 * "<mibew root>/plugins/<Vendor Name>/Mibew/Plugin/<Plugin name>/Plugin.php"
 * file. Names of plugin and directories/files are case sensitive!
 *
 * To turn the plugin on add its definition to the following to "plugins"
 * structure in <mibew root>/configs/config.yml if the "plugins" structure looks
 * like:
 * <code>
 * plugins: []
 * </code>
 * it will become:
 * <code>
 * plugins:
 *     -
 *         name: "Mibew:Boilerplate"
 *         config:
 *             very_important_value: "$3.50"
 * </code>
 */

namespace Mibew\Mibew\Plugin\Boilerplate;

/**
 * Defenition of the main plugin class.
 *
 * Plugin class must implements \Mibew\Plugin\PluginInterface and can extends
 * \Mibew\Plugin\AbstractPlugin class. The latter contains basic functions that
 * can be helpfull.
 */
class Plugin extends \Mibew\Plugin\AbstractPlugin implements \Mibew\Plugin\PluginInterface
{
    /**
     * Determine if the plugin was initialized correctly or not.
     *
     * By setting this propery to true by default we can make the plugin
     * initialized by default, so there is no need to add custom contructor
     * or initializer.
     *
     * This propery is overridden here only for example. We do not need to do
     * so in each plugin. In general case it should be set to true in the plugin
     * constructor when all necessary checks will be passed.
     *
     * Another way to control initialization state of the plugin is by means of
     * {@link \Mibew\Plugin\PluginInterface::initialized()} method.
     */
    protected $initialized = true;

    /**
     * Plugin's constructor.
     *
     * The code is situated here can initialize the plugin but cannot depend
     * on other plugins. All dependent code should be placed in "run" method.
     *
     * The current implementation just checks plugin's configurations.
     *
     * @param array $config Associative array of configuration params from the
     * main config file.
     */
    public function __construct($config)
    {
        // Check if a fake config param is set or it does not. In the sake of
        // simplicity we do not check the value.
        if (!isset($config['very_important_value'])) {
            // "very_important_value" param was not set. In this case we cannot
            // initialize the plugin correctly, so we need to tell the system
            // about it.
            $this->initialized = false;
        }
    }

    /**
     * The main entry point of a plugin
     *
     * If a plugin extends \Mibew\Plugin\AbstructPlugin class the only method
     * that should be implemented is "run".
     *
     * Here we can attach event listeners and do other job.
     */
    public function run()
    {
        // We need an instatance of EventDispatcher class to attach handlers to
        // events. So get it.
        $dispatcher = \Mibew\EventDispatcher::getInstance();
        // There are a lot of events. Use a few of them to show how they work.
        $dispatcher->attachListener('pageAddCSS', $this, 'addCustomCss');
    }

    /**
     * Just attaches custom CSS file to every page that support it (chat windows
     * and users waiting screen).
     *
     * @param array $args Associative array of arguments passed in to event
     * handler. The list of arguments can vary for different events. See an
     * event description to know which arguments are available and how they
     * should be used.
     */
    public function addCustomCss(&$args)
    {
        $args['css'][] = $args['request']->getBasePath()
            . '/' . $this->getFilesPath() . '/css/styles.css';
    }

    /**
     * Also we can add dependencies. But make sure that they were loaded BEFORE
     * current plugin in config.php
     *
     * If the plugin depends, for example, on "Abc:BestFeature" and "Xyz:Logger"
     * we need to return the following array:
     * <code>
     * return array(
     *     'Abc:BestFeature',
     *     'Xyz:Logger',
     * );
     * </code>
     */
    public static function getDependencies()
    {
        // This plugin does not depend on others so return an empty array.
        return array();
    }
}