displaytweets.php

<?php

/*
    Plugin Name: Display Tweets
    Plugin URI: http://matthewruddy.com/display-tweets-plugin
    Version: 1.0.3
    Author: Matthew Ruddy
    Author URI: http://matthewruddy.com/
    Description: A rather simple Twitter feed plugin that uses the v1.1 Twitter API.
    License: GNU General Public License v2.0 or later
    License URI: http://www.opensource.org/licenses/gpl-license.php

    Copyright 2013

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License, version 2, as
    published by the Free Software Foundation.

    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, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

/** Let's go! */
if ( class_exists( 'DisplayTweets' ) )
    DisplayTweets::get_instance();

/**
 * Main plugin class
 *
 * @author Matthew Ruddy
 * @since 1.0
 */
class DisplayTweets {

    /**
     * Class instance
     *
     * @since 1.0
     */
    private static $instance;

    /**
     * Our plugin version
     *
     * @since 1.0
     */
    public static $version = '1.0.3';

    /**
     * How often the tweets are refreshed (in seconds). Defualt is five minutes.
     *
     * @since 1.0
     */
    public static $refresh = 300;

    /**
     * URL for registering a Twitter application
     *
     * @since 1.0
     */
    public static $registration_url = 'http://dev.twitter.com/apps/new';

    /**
     * Getter method for retrieving the class instance.
     *
     * @since 1.0
     */
    public static function get_instance() {
    
        if ( !self::$instance instanceof self )
            self::$instance = new self;
        return self::$instance;
    
    }
    
    /**
     * Constructor
     *
     * @since 1.0
     */
    private function __construct() {

        /** Get the plugin name */
        $plugin = plugin_basename( __FILE__ );

        /** Load plugin textdomain for language capabilities */
        load_plugin_textdomain( 'displaytweets', false, dirname( plugin_basename( __FILE__ ) ) . '/languages' );

        /** Activation and deactivation hooks. Static methods are used to avoid activation/uninstallation scoping errors. */
        if ( is_multisite() ) {
            register_activation_hook( __FILE__, array( __CLASS__, 'do_network_activation' ) );
            register_uninstall_hook( __FILE__, array( __CLASS__, 'do_network_uninstall' ) );
        }
        else {
            register_activation_hook( __FILE__, array( __CLASS__, 'do_activation' ) );
            register_uninstall_hook( __FILE__, array( __CLASS__, 'do_uninstall' ) );
        }

        /** Hooks actions & shortcodes */
        add_action( 'admin_menu', array( $this, 'add_settings_page' ) );
        add_action( 'admin_menu', array( $this, 'save_settings' ) );
        add_filter( "plugin_action_links_{$plugin}", array( $this, 'add_settings_link' ) );
        add_shortcode( 'display_tweets', array( $this, 'do_shortcode' ) );

        /** Custom actions hook */
        do_action_ref_array( 'displaytweets', array( $this ) );

    }
    
    /**
     * Executes a network activation
     *
     * @since 2.0
     */
    public static function do_network_activation() {
        self::get_instance()->network_activate();
    }
    
    /**
     * Executes a network uninstall
     *
     * @since 2.0
     */
    public static function do_network_uninstall() {
        self::get_instance()->network_uninstall();
    }
    
    /**
     * Executes an activation
     *
     * @since 2.0
     */
    public static function do_activation() {
        self::get_instance()->activate();
    }
    
    /**
     * Executes an uninstall
     *
     * @since 2.0
     */
    public static function do_uninstall() {
        self::get_instance()->uninstall();
    }
    
    /**
     * Network activation hook
     *
     * @since 2.0
     */
    public function network_activate() {

        /** Do plugin version check */
        if ( !$this->version_check() )
            return;

        /** Get all of the blogs */
        $blogs = $this->get_multisite_blogs();

        /** Execute acivation for each blog */
        foreach ( $blogs as $blog_id ) {
            switch_to_blog( $blog_id );
            $this->activate();
            restore_current_blog();
        }

        /** Trigger hooks */
        do_action_ref_array( 'displaytweets_network_activate', array( $this ) );

    }
    
    /**
     * Network uninstall hook
     *
     * @since 2.0
     */
    public function network_uninstall() {

        /** Get all of the blogs */
        $blogs = $this->get_multisite_blogs();

        /** Execute uninstall for each blog */
        foreach ( $blogs as $blog_id ) {
            switch_to_blog( $blog_id );
            $this->uninstall();
            restore_current_blog();
        }

        /** Trigger hooks */
        do_action_ref_array( 'displaytweets_network_uninstall', array( $this ) );

    }
    
    /**
     * Activation hook
     *
     * @since 2.0
     */
    public function activate() {

        /** Do plugin version check */
        if ( !$this->version_check() )
            return;

        /** Add database options */
        add_option( 'displaytweets_version', self::$version );
        add_option( 'displaytweets_settings', array(
            'consumer_key' => null,
            'consumer_secret' => null,
            'access_token' => null,
            'access_token_secret' => null,
            'screen_name' => 'matthewruddycom',
            'count' => 5,
            'include_rts' => true,
            'exclude_replies' => false
        ) );

        /** Trigger hooks */
        do_action_ref_array( 'displaytweets_activate', array( $this ) );

    }
    
    /**
     * Uninstall Hook
     *
     * @since 1.0
     */
    public function uninstall() {

        /** Delete options and transients */
        delete_option( 'displaytweets_version' );
        delete_option( 'displaytweets_settings' );
        delete_transient( 'displaytweets_tweets' );

        /** Trigger hooks */
        do_action_ref_array( 'displaytweets_uninstall', array( $this ) );

    }
    
    /**
     *  Does a plugin version check, making sure the current Wordpress version is supported. If not, the plugin is deactivated and an error message is displayed.
     *
     *  @version 1.0
     */
    public function version_check() {
        global $wp_version;
        if ( version_compare( $wp_version, '3.5', '<' ) ) {
            deactivate_plugins( plugin_basename( __FILE__ ) );
            wp_die( __( sprintf( 'Sorry, but your version of WordPress, <strong>%s</strong>, is not supported. The plugin has been deactivated. <a href="%s">Return to the Dashboard.</a>', $wp_version, admin_url() ), 'displaytweets' ) );
            return false;
        }
        return true;
    }
    
    /**
     * Returns the ids of the various multisite blogs. Returns false if not a multisite installation.
     *
     * @since 1.0.2
     */
    public function get_multisite_blogs() {

        global $wpdb;

        /** Bail if not multisite */
        if ( !is_multisite() )
            return false;

        /** Get the blogs ids from database */
        $query = "SELECT blog_id from $wpdb->blogs";
        $blogs = $wpdb->get_col($query);

        /** Push blog ids to array */
        $blog_ids = array();
        foreach ( $blogs as $blog )
            $blog_ids[] = $blog;

        /** Return the multisite blog ids */
        return $blog_ids;

    }

    /**
     * Adds a plugin settings page
     *
     * @since 1.0
     */
    public function add_settings_page() {
        add_options_page(
            __( 'Twitter Feed Settings', 'displaytweets' ),
            __( 'Twitter Feed', 'displaytweets' ),
            'edit_plugins',
            'displaytweets',
            array( $this, 'settings_view' )
        );
    }

    /**
     * Adds a settings link to the "Plugins" panel
     *
     * @since 1.0.3
     */
    public function add_settings_link($links) {
        array_unshift($links, '<a href="options-general.php?page=displaytweets">Settings</a>');
        return $links; 
    }

    /**
     * Validates the settings
     *
     * @since 1.0
     */
    public function validate_settings( $settings ) {
        foreach ( $settings as $index => $setting ) {
            if ( $setting === 'true' || $setting === 'false' )
                $settings[ $index ] = filter_var( $setting, FILTER_VALIDATE_BOOLEAN );
        }
        return $settings;
    }

    /**
     * Saves the plugin settings
     *
     * @since 1.0
     */
    public function save_settings() {

        /** Bail if not our plugin page or not saving settings */
        if ( !isset( $_GET['page'] ) )
            return;
        if ( $_GET['page'] != 'displaytweets' )
            return;
        if ( !isset( $_POST['settings'] ) )
            return;

        /** Security check. */
        if ( !check_admin_referer( "displaytweets-save_{$_GET['page']}", "displaytweets-save_{$_GET['page']}" ) ) {
            wp_die( __( 'Security check has failed. Save has been prevented. Please try again.', 'displaytweets' ) );
            exit();
        }

        /** Save the settings */
        update_option( 'displaytweets_settings', stripslashes_deep( $this->validate_settings( $_POST['settings'] ) ) );

        /** Delete the old transient to force a refresh */
        delete_transient( 'displaytweets_tweets' );

        /** Display success message */
        add_action( 'admin_notices', create_function( '', 'echo "<div class=\"message updated\"><p>'. __( 'Settings have been saved successfully.', 'displaytweets' ) .'</p></div>";' ) );

    }
    
    /**
     * Executes a shortcode handler
     *
     * @since 1.0
     */
    public function do_shortcode( $atts ) {

        /** Return the tweets to be printed by the shortcode */
        ob_start();
        $this->show();
        return ob_get_clean();

    }

    /**
     * Prints the settings page view
     *
     * @since 1.0
     */
    public function settings_view() {

    /** Get the plugin settings */
    $settings = $s = $this->validate_settings( get_option( 'displaytweets_settings' ) );

    /** Print the view */
    ?>
    <div class="wrap">
        <div id="icon-edit" class="icon32 icon32-posts-post"><br></div>
        <h2><?php _e( 'Twitter Feed Configuration', 'displaytweets' ); ?></h2>
        <form name="post" action="options-general.php?page=displaytweets" method="post">
            <?php
                /** Security nonce field */
                wp_nonce_field( "displaytweets-save_{$_GET['page']}", "displaytweets-save_{$_GET['page']}", false );
            ?>

            <div class="main-panel">
                <div class="section">
                    <h3><?php _e( 'Authentication', 'displaytweets' ); ?></h3>
                    <p><?php _e( 'Twitter\'s v1.1 API requires authentication. For this you need to <a href="'. self::$registration_url .'">register an application here</a>. Follow the instructions and that\'s it, you\'re authenticated.', 'displaytweets' ); ?></p>
                    <table class="form-table settings">
                        <tbody>
                            <tr valign="top">
                                <th scope="row"><label for="consumer_key"><?php _e( 'Consumer Key', 'displaytweets' ); ?></label></th>
                                <td>
                                    <input type="text" name="settings[consumer_key]" id="consumer_key" class="regular-text" value="<?php echo $s['consumer_key']; ?>">
                                    <p class="description"><?php _e( 'Enter your Consumer Key.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>

                            <tr valign="top">
                                <th scope="row"><label for="consumer_secret"><?php _e( 'Consumer Secret', 'displaytweets' ); ?></label></th>
                                <td>
                                    <input type="password" name="settings[consumer_secret]" id="consumer_secret" class="regular-text" value="<?php echo $s['consumer_secret']; ?>">
                                    <p class="description"><?php _e( 'Enter your Consumer Secret. Keep this private, do not share it.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>

                            <tr valign="top">
                                <th scope="row"><label for="access_token"><?php _e( 'Access Token', 'displaytweets' ); ?></label></th>
                                <td>
                                    <input type="text" name="settings[access_token]" id="access_token" class="regular-text" value="<?php echo $s['access_token']; ?>">
                                    <p class="description"><?php _e( 'Enter your Access Token.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>

                            <tr valign="top">
                                <th scope="row"><label for="access_token_secret"><?php _e( 'Access Token Secret', 'displaytweets' ); ?></label></th>
                                <td>
                                    <input type="password" name="settings[access_token_secret]" id="access_token_secret" class="regular-text" value="<?php echo $s['access_token_secret']; ?>">
                                    <p class="description"><?php _e( 'Enter your Access Token Secret. Keep this private also, do not share it.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>
                        </tbody>
                    </table>
                </div>

                <div class="section">
                    <h3><?php _e( 'Configuration', 'displaytweets' ); ?></h3>
                    <p><?php _e( 'Here you can alter some of the basic Twitter feed settings.', 'displaytweets' ); ?></p>
                    <table class="form-table settings">
                        <tbody>
                            <tr valign="top">
                                <th scope="row"><label for="screen_name"><?php _e( 'Screen Name', 'displaytweets' ); ?></label></th>
                                <td>
                                    <input type="text" name="settings[screen_name]" id="screen_name" class="regular-text" value="<?php echo $s['screen_name']; ?>">
                                    <p class="description"><?php _e( 'The screen name of the user for whom to return results for.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>

                            <tr valign="top">
                                <th scope="row"><label for="count"><?php _e( 'Count', 'displaytweets' ); ?></label></th>
                                <td>
                                    <input type="number" step="1" min="1" name="settings[count]" id="count" value="<?php echo $s['count']; ?>">
                                    <p class="description"><?php _e( 'Specifies the number of tweets to try and retrieve, up to a maximum of 200.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>

                            <tr valign="top">
                                <th scope="row"><?php _e( 'Include Retweets', 'displaytweets' ); ?></th>
                                <td>
                                    <fieldset>
                                        <legend class="screen-reader-text"><span><?php _e( 'Include Retweets', 'displaytweets' ); ?></span></legend>
                                        
                                        <label for="include_rts_true"><input type="radio" name="settings[include_rts]" id="include_rts_true" value="true" <?php checked( $s['include_rts'], true ); ?>>
                                            <span><?php _e( 'Yes', 'displaytweets' ); ?></span>
                                        </label>
                                        <br />

                                        <label for="include_rts_false"><input type="radio" name="settings[include_rts]" id="include_rts_false" value="false" <?php checked( $s['include_rts'], false ); ?>>
                                            <span><?php _e( 'No', 'displaytweets' ); ?></span>
                                        </label>
                                    </fieldset>
                                    <p class="description"><?php _e( 'When set to "No", the timeline will not show any retweets.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>

                            <tr valign="top">
                                <th scope="row"><?php _e( 'Exclude Replies', 'displaytweets' ); ?></th>
                                <td>
                                    <fieldset>
                                        <legend class="screen-reader-text"><span><?php _e( 'Exclude Replies', 'displaytweets' ); ?></span></legend>
                                        
                                        <label for="exclude_replies_true"><input type="radio" name="settings[exclude_replies]" id="exclude_replies_true" value="true" <?php checked( $s['exclude_replies'], true ); ?>>
                                            <span><?php _e( 'Yes', 'displaytweets' ); ?><span>
                                        </label>
                                        <br />
                                        
                                        <label for="exclude_replies_false"><input type="radio" name="settings[exclude_replies]" id="exclude_replies_false" value="false" <?php checked( $s['exclude_replies'], false ); ?>>
                                            <span><?php _e( 'No', 'displaytweets' ); ?><span>
                                        </label>
                                    </fieldset>
                                    <p class="description"><?php _e( 'This parameter will prevent replies from appearing in the returned timeline. Setting this to "No" will mean you will receive up-to count tweets — this is because the count parameter retrieves that many tweets before filtering out retweets and replies.', 'displaytweets' ); ?></p>
                                </td>
                            </tr>
                        </tbody>
                    </table>
                </div>

                <p class="submit">
                    <input type="submit" name="save" class="button button-primary button-large" id="save" accesskey="p" value="<?php _e( 'Save Settings', 'displaytweets' ); ?>">
                </p>
            </div>
        </form>
    </div>
    <?php

    }

    /**
     * Formats tweet text to add URLs and hashtags
     *
     * @since 1.0
     */
    public function format_tweet( $text ) {
        $text = preg_replace( "#(^|[\n ])([\w]+?://[\w]+[^ \"\n\r\t< ]*)#", "\\1<a href=\"\\2\" target=\"_blank\">\\2</a>", $text );
        $text = preg_replace( "#(^|[\n ])((www|ftp)\.[^ \"\t\n\r< ]*)#", "\\1<a href=\"http://\\2\" target=\"_blank\">\\2</a>", $text );
        $text = preg_replace( "/@(\w+)/", "<a href=\"http://www.twitter.com/\\1\" target=\"_blank\">@\\1</a>", $text );
        $text = preg_replace( "/#(\w+)/", "<a href=\"http://twitter.com/search?q=%23\\1&src=hash\" target=\"_blank\">#\\1</a>", $text );
        return $text;
    }

    /**
     * Gets the tweets
     *
     * @since 1.0
     */
    public function get() {

        /** Get settings */
        $settings = $this->validate_settings( get_option( 'displaytweets_settings' ) );

        /** Merge arugments with defaults */
        $args = apply_filters( 'displaytweets_args', array(
            'screen_name' => $settings['screen_name'],
            'count' => $settings['count'],
            'include_rts' => $settings['include_rts'],
            'exclude_replies' => $settings['exclude_replies']
        ) );

        /** Get tweets from transient. False if it has expired */
        $tweets = get_transient( "displaytweets_tweets" );
        if ( $tweets === false ) {

            /** Require the twitter auth class */
            if ( !class_exists('TwitterOAuth') )
                require_once 'includes/Twitter/twitteroauth/twitteroauth.php';

            /** Get Twitter connection */
            $twitterConnection = new TwitterOAuth(
                $settings['consumer_key'],
                $settings['consumer_secret'],
                $settings['access_token'],
                $settings['access_token_secret']
            );

            /** Get tweets */
            $tweets = $twitterConnection->get(
                'statuses/user_timeline',
                $args
            );

            /** Bail if failed */
            if ( !$tweets || isset( $tweets->errors ) )
                return false;

            /** Set tweets */
            set_transient( "displaytweets_tweets", $tweets, apply_filters( 'displaytweets_refresh_timeout', self::$refresh ) );

        }

        /** Return tweets */
        return $tweets;

    }

    /**
     * Prints the tweets
     *
     * @since 1.0
     */
    public function show() {

        /** Get the tweets */
        $tweets = $this->get();

        /** Bail if there are no tweets */
        if ( !$tweets ) {
            if ( current_user_can( 'edit_plugins' ) )
                echo '<p style="color: red;">'. __( 'No tweets found. Please make sure your settings are correct.', 'displaytweets' ) .'</p>';
            return;
        }

        /** Print the tweets */
        foreach ( $tweets as $tweet ) {

            if ( has_action( 'displaytweets_tweet_template' ) ) :

                /** Execute action that should print the tweet template */
                do_action( 'displaytweets_tweet_template', $tweet );

            else :

                /** Set the date and time format */
                $datetime_format = apply_filters( 'displaytweets_datetime_format', "l M j \- g:ia" );

                /** Get the date and time posted as a nice string */
                $posted_since = apply_filters( 'displaytweets_posted_since', date_i18n( $datetime_format , strtotime( $tweet->created_at ) ) );

                /** Filter for linking dates to the tweet itself */
                $link_date = apply_filters( 'displaytweets_link_date_to_tweet', __return_false() );
                if ( $link_date )
                    $posted_since = "<a href=\"https://twitter.com/{$tweet->user->screen_name}/status/{$tweet->id_str}\">{$posted_since}</a>";

                /** Print tweet */
                echo "<p>{$this->format_tweet( $tweet->text )}<br /><small class=\"muted\">- {$posted_since}</small></p>";

            endif;
        }

    }

}

/**
 * "Twitter Feed" WordPress widget
 *
 * @author Matthew Ruddy
 * @since 1.0
 */
add_action( 'widgets_init', create_function( '', 'register_widget( "DT_Widget" );' ) );
class DT_Widget extends WP_Widget {

    /**
     * Constructor
     *
     * @since 1.0
     */
    public function __construct() {
        parent::__construct(
            'displaytweetswidget',
            __( 'Tweets', 'displaytweets' ),
            array( 'description' => __( 'Display your Twitter feed.', 'displaytweets' ) )
        );
    }

    /**
     * Widget logic
     *
     * @since 1.0
     */
    public function widget( $args, $instance ) {

        /** Extract arguments */
        extract( $args );

        /** Get widget title */
        $title = apply_filters( 'widgets_title', $instance['title'] );

        /** Display widget header */
        echo $before_widget;
        if ( !empty( $title ) )
            echo $before_title . $title . $after_title;
        
        /** Display tweets */
        if ( function_exists( 'display_tweets' ) )
            display_tweets();

        /** Display widget footer */
        echo $after_widget;


    }

    /**
     * Returns updated settings array. Also does some sanatization.
     *
     * @since 1.0
     */
    public function update( $new_instance, $old_instance ) {
        return array(
            'title' => strip_tags( $new_instance['title'] )
        );
    }

    /**
     * Widget settings form
     *
     * @since 1.0
     */
    public function form( $instance ) {
        ?>
        <p>
            <label for="<?php echo $this->get_field_id( 'title' ); ?>"><?php _e( 'Title', 'displaytweets' ); ?></label>
            <input type="text" id="<?php echo $this->get_field_id( 'title' ); ?>" name="<?php echo $this->get_field_name( 'title' ); ?>" class="widefat" value="<?php if ( isset( $instance['title'] ) ) echo esc_attr( $instance['title'] ); ?>">
        </p>
        <?php
    }

}

/**
 * Helper function for displaying tweets
 *
 * @author Matthew Ruddy
 * @since 1.0
 */
if ( !function_exists( 'display_tweets' ) ) {
    function display_tweets() {
        DisplayTweets::get_instance()->show();
    }
}