<?php
if ( ! defined( 'ABSPATH' ) ) exit();

/**
 * Subscription Manager class
 */
class LD_Notifications_Subscription_Manager {
    /**
     * WP_Query's query_vars
     * @var array
     */
    public static $query_vars;

    /**
     * URL slug for the notifications subscription manager.
     *
     * @var string
     */
    public static $slug;

    /**
     * Init the class
     * @return void
     */
    public static function init() {
        self::$slug = apply_filters( 'learndash_notifications_subscription_page_slug', 'learndash-notifications-subscription' );

        add_filter( 'learndash_notifications_email_content', [ __CLASS__, 'subscription_notice' ], 99, 2 );

        add_action( 'template_redirect', [ __CLASS__, 'redirect_to_login_page' ] );
        add_action( 'template_include', [ __CLASS__, 'subscription_page' ] );
        add_filter( 'document_title_parts', [ __CLASS__, 'subscription_page_title' ] );

        add_action( 'init', [ __CLASS__, 'save_subscriptions' ] );
    }

    /**
     * Init and get query vars
     * @return array
     */
    public static function get_query_vars() {
        global $wp_query;
        return $wp_query->query_vars;
    }

    /**
     * Add subscription manager notice at the end of notification email
     *
     * @param  string $content         Original email content
     * @param  int    $notification_id Notification post ID
     * @return string                  New returned email content
     */
    public static function subscription_notice( $content, $notification_id )
    {
        $content .= '<p class="subscription-manager-notice" style="font-size: 12px; font-style: italic;">';
            $content .= sprintf( __( 'Don\'t want to receive this email anymore? <a href="%s">Click here</a> to manage your notification email subscriptions.', 'learndash-notifications' ), home_url( trailingslashit( self::$slug ) ) );
        $content .= '</p>';

        return $content;
    }

    /**
     * Redirect to login page if user is not logged in
     * @return void
     */
    public static function redirect_to_login_page() {
        $query_vars = self::get_query_vars();

        if ( ! is_user_logged_in() && array_search( self::$slug, $query_vars, true ) !== false ) {
            $login_page = wp_login_url( home_url( trailingslashit( self::$slug ) ) );

            wp_safe_redirect( $login_page );
            exit();
        }
    }

    /**
     * Change template to subscription
     * @param  string $template Default template path
     * @return string           Template path
     */
    public static function subscription_page( $template ) {
        $query_vars = self::get_query_vars();

        if ( is_user_logged_in() && array_search( self::$slug, $query_vars, true ) !== false ) {
            http_response_code( 200 );
            return LEARNDASH_NOTIFICATIONS_PLUGIN_PATH . 'templates/subscription-page.php';
        } else {
            return $template;
        }
    }

    /**
     * Change subscription page title
     * @param  string $title Default title
     * @return string        New title
     */
    public static function subscription_page_title( $title ) {
        $query_vars = self::get_query_vars();

        if ( array_search( self::$slug, $query_vars, true ) !== false ) {
            $title['title'] = __( 'LearnDash Notifications Subscription', 'learndash-notifications' );
        }

        return $title;
    }

    /**
     * Save user notifications subscription setting
     * @return void
     */
    public static function save_subscriptions() {
        if ( ! isset( $_POST['action'] ) || $_POST['action'] !== 'learndash_notifications_subscription' ) {
            return;
        }

        if ( ! wp_verify_nonce( $_POST['ld_nonce'], 'learndash_notifications_subscription' ) ) {
            return;
        }

        $user_id = intval( $_POST['user_id'] );

        if ( empty( $user_id ) ) {
            return;
        }

        $triggers = learndash_notifications_get_triggers();
        $subscriptions = [];
        foreach ( $triggers as $key => $label ) {
            if ( isset( $_POST[ $key ] ) && $_POST[ $key ] == 1 ) {
                $subscriptions[ $key ] = 1;
            } else {
                $subscriptions[ $key ] = 0;
            }
        }

        $update = update_user_meta( $user_id, 'learndash_notifications_subscription', $subscriptions );

        if ( $update ) {
            $redirect_url = add_query_arg( [ 'message' => 'success' ], home_url( trailingslashit( self::$slug ) ) );
        } else {
            $redirect_url = add_query_arg( [ 'message' => 'fail' ], home_url( trailingslashit( self::$slug ) ) );
        }

        wp_redirect( $redirect_url );
        exit();
    }
}

LD_Notifications_Subscription_Manager::init();