<?php

/**
 * LDCCRM For Wordpress usage
 * php version 5
 *
 * @category API
 * @package  None
 * @author   Jérémy Munsch <jeremy.munsch@ldc.fr>
 * @license  MIT https://opensource.org/licenses/MIT
 * @version  GIT: 0.0.1
 * @link     /
 */

namespace LDCCRM;

use Exception;

// TABLE LDC CUSTOMERS
// CREATE TABLE `ldc_wp_customers` (
//  `crm_id` BIGINT NOT NULL COMMENT 'Le CRM ID',
//  `hashcode` VARCHAR(36) NOT NULL DEFAULT '' COMMENT 'Le hashcode (UUID)',
//  `email` VARCHAR(255) NOT NULL DEFAULT '' COMMENT 'Le customer email',
//  PRIMARY KEY (`crm_id`),
//  UNIQUE INDEX `hashcode` (`hashcode`)
// )
// COMMENT='Les customers sur un WP liées à la CRM'
// COLLATE='utf8mb4_unicode_ci';

/**
 * Class de gestion des users en session avec Wordpress (ce truc immonde)
 * Compatible avec php5
 *
 * @category API
 * @package  None
 * @author   Jérémy Munsch <jeremy.munsch@ldc.fr>
 * @license  MIT https://opensource.org/licenses/MIT
 * @link     /
 */
class WPCrm extends ApiV1
{

    private static $_sessionKey = 'LDC_CRM_USER';

    private static $_sessionDestroyed = false;

    /**
     * The user object
     *
     * @var \LDCCRM\ApiV1
     */
    protected static $api = null;

    /**
     * The user object
     *
     * @var \LDCCRM\WPCrmUser
     */
    protected static $user = null;

    /**
     * Try to login with CRM API
     * return api response code if an error occurs
     *
     * @param string $email    The customer email
     * @param string $password The customer password
     *
     * @return \LDCCRM\WPCrmUser|int
     */
    public static function login($email, $password)
    {
        self::_bootSessionIfNeeded();
        return self::_loginUserWithApi($email, $password);
    }

    /**
     * Get the current user
     * return null if the user is not logged in
     *
     * @return \LDCCRM\WPCrmUser|null
     */
    public static function getUser()
    {
        self::_bootSessionIfNeeded();
        return self::$user;
    }

    /**
     * Get the current user
     * return api response code if an error occurs
     *
     * @param string $email The customer email
     *
     * @return \LDCCRM\WPCrmUser|int
     */
    public static function getUserFromApi($email)
    {
        self::_initLDCApi();
        /**
         * Object response
         *
         * @var object
         */
        $response = self::$api->getCustomerByEmail($email);
        if ($response->status === 'KO') {
            error_log(
                sprintf(
                    'LDC CRM: returned KO from CRM => %s',
                    $response->message
                )
            );
            return $response->code;
        }
        self::_setUser(
            $response->user->crm_id,
            $response->user->hashcode,
            $response->user->email,
            $response
        );
        return self::$user;
    }

    /**
     * Get the current user
     * return null if the user is not logged in
     *
     * @param string $email    The customer email
     * @param string $password The customer password
     *
     * @return \LDCCRM\WPCrmUser|int
     */
    private static function _loginUserWithApi($email, $password)
    {
        self::_initLDCApi();
        /**
         * Object response
         *
         * @var object
         */
        $response = self::$api->loginCustomer($email, $password);
        if ($response->status === 'KO') {
            error_log(
                sprintf(
                    'LDC CRM: returned KO from CRM => %s',
                    $response->message
                )
            );
            return $response->code;
        }
        self::_setUser(
            $response->user->crm_id,
            $response->user->hashcode,
            $response->user->email,
            $response
        );
        self::_saveOrUpdateUserToTable();
        return self::$user;
    }

    /**
     * Destroy the customer from session
     * and therefore logout
     *
     * @return void
     */
    public static function logout()
    {
        self::_bootSessionIfNeeded();
        unset($_SESSION[self::$_sessionKey]);
        session_destroy();
        self::$_sessionDestroyed = true;
    }

    /**
     * Check if the user is Authenticated
     *
     * @return bool
     */
    public static function check()
    {
        self::_bootSessionIfNeeded();
        return (bool) self::getUser();
    }

    /**
     * Create a user
     * stores it to the session
     * and finally saves it to the database if it does not exists
     *
     * @param int    $crm_id   The crm id
     * @param string $hashcode The customer hashcode (UUID)
     * @param string $email    The customer email
     * @param object $response The crm API response
     *
     * @return void
     */
    private static function _setUser($crm_id, $hashcode, $email, $response)
    {
        self::_bootSessionIfNeeded();
        if (!self::$user) {
            self::$user = new WPCrmUser($crm_id, $hashcode, $email);
        }
        self::$user->setInfo($response->user);
        $_SESSION[self::$_sessionKey] = json_encode(self::$user);
    }

    /**
     * Get the initialized API object
     *
     * @return \LDCCRM\ApiV1
     */
    private static function _initLDCApi()
    {
        if (!self::$api) {
            if (!extension_loaded('curl')) {
                throw new Exception(
                    'LDC CRM require php extension curl'
                );
            }
            $endpoint = getenv('CRM_ENDPOINT');
            $api_key = getenv('CRM_API_TOKEN');
            if ($endpoint === false or $api_key === false) {
                throw new Exception(
                    'LDC CRM require .env to have CRM_ENDPOINT and CRM_API_TOKEN'
                );
            }
            self::$api = new ApiV1($endpoint, $api_key);
        }
        return self::$api;
    }

    /**
     * Boot the php session if needed
     *
     * @return void
     */
    private static function _bootSessionIfNeeded()
    {
        if (!session_id() && !self::$_sessionDestroyed) {
            session_start();
        }
        if (!self::$user and array_key_exists(self::$_sessionKey, $_SESSION)) {
            /**
             * The user object
             *
             * @var \LDCCRM\WPCrmUser
             */
            self::$user = WPCrmUser::parseFromJson(
                $_SESSION[self::$_sessionKey] ?? null
            );
        }
    }

    /**
     * Get a customer from table
     *
     * @param int $crm_id The customer crm id
     *
     * @return object|null
     */
    public static function getUserToTable($crm_id)
    {
        return self::_getWpDB()->get_row(
            'SELECT * FROM `ldc_wp_customers` WHERE `crm_id` = ' .
            self::$user->crm_id
        );
    }

    /**
     * Save or update the user to the table
     *
     * @return void
     */
    private static function _saveOrUpdateUserToTable()
    {
        if (self::getUserToTable(self::$user->crm_id)) {
            self::_query(
                'UPDATE `ldc_wp_customers` SET `hashcode` = %d, `email` = %d' .
                    ' WHERE `crm_id` = %d',
                [
                    'crm_id' => self::$user->crm_id,
                    'hashcode' => self::$user->hashcode,
                    'email' => self::$user->email,
                ]
            );
        } else {
            self::_query(
                'INSERT INTO `ldc_wp_customers` VALUES (%d, %s, %s)',
                [
                    'crm_id' => self::$user->crm_id,
                    'hashcode' => self::$user->hashcode,
                    'email' => self::$user->email,
                ]
            );
        }
    }

    /**
     * Query in DB
     *
     * @param string $query  La request avec les variables en points d'interrogation
     * @param array  $params Les paramètres des la requète
     *
     * @return object Containing the row columns
     */
    private static function _query($query, array $params = [])
    {
        return self::_getWpDB()->query(
            self::_getWpDB()->prepare($query, $params)
        );
    }

    /**
     * Get WP 'pdo instance'
     *
     * @return object The $wpdb variable
     */
    private static function _getWpDB()
    {
        global $wpdb;
        return $wpdb;
    }
}