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<?php

defined( 'ABSPATH' ) || exit;

if ( ! function_exists( 'vsp_ajax_action' ) ) {
    /**
     * Check if current request has action parameter and returns it
     *
     * @return bool
     */
    function vsp_ajax_action() {
        return ( vsp_is_request( 'ajax' ) && isset( $_REQUEST['action'] ) ) ? $_REQUEST['action'] : false;
    }
}

if ( ! function_exists( 'vsp_is_heartbeat' ) ) {
    /**
     * Checks if current request is heartbeat
     *
     * @return bool
     */
    function vsp_is_heartbeat() {
        return ( vsp_is_ajax() === true && vsp_is_ajax( 'heartbeat' ) === true ) ? true : false;
    }
}

if ( ! function_exists( 'vsp_is_ajax' ) ) {
    /**
     * Checks if current request is ajax
     * Also takes required action key to check if the ajax is exactly the action is passed
     *
     * @param string $action .
     *
     * @return bool
     */
    function vsp_is_ajax( $action = '' ) {
        if ( empty( $action ) ) {
            return vsp_is_request( 'ajax' );
        }

        return ( vsp_ajax_action() !== false && vsp_ajax_action() === $action ) ? true : false;
    }
}

if ( ! function_exists( 'vsp_is_cron' ) ) {
    /**
     * Checks if current request is cron
     *
     * @return bool
     */
    function vsp_is_cron() {
        return vsp_is_request( 'cron' );
    }
}

if ( ! function_exists( 'vsp_is_admin' ) ) {
    /**
     * Checks if current request is admin
     *
     * @return bool
     */
    function vsp_is_admin() {
        return vsp_is_request( 'admin' );
    }
}

if ( ! function_exists( 'vsp_is_frontend' ) ) {
    /**
     * Checks if current request is frontend
     *
     * @return bool
     */
    function vsp_is_frontend() {
        return vsp_is_request( 'frontend' );
    }
}

if ( ! function_exists( 'vsp_is_request' ) ) {
    /**
     * Checks What kind of request is it.
     *
     * @param string $type .
     *
     * @return bool
     */
    function vsp_is_request( $type ) {
        switch ( $type ) {
            case 'admin':
                return is_admin();
            case 'ajax':
                return defined( 'DOING_AJAX' );
            case 'cron':
                return defined( 'DOING_CRON' );
            case 'frontend':
                return ( ! is_admin() || defined( 'DOING_AJAX' ) ) && ! defined( 'DOING_CRON' );
        }
        return false;
    }
}