<?php

/**
 * The public-facing functionality of the plugin.
 *
 * @link       https://horizontes.info
 * @since      1.0.0
 *
 * @package    Reuna_Mailchimp
 * @subpackage Reuna_Mailchimp/public
 */

use \DrewM\MailChimp\MailChimp;

/**
 * The public-facing functionality of the plugin.
 *
 * Defines the plugin name, version, and two examples hooks for how to
 * enqueue the public-facing stylesheet and JavaScript.
 *
 * @package    Reuna_Mailchimp
 * @subpackage Reuna_Mailchimp/public
 * @author     Horizontes Coop. <contato@horizontes.info>
 */
class Reuna_Mailchimp_Public {

	/**
	 * The ID of this plugin.
	 *
	 * @since    1.0.0
	 * @access   private
	 * @var      string    $plugin_name    The ID of this plugin.
	 */
	private $plugin_name;

	/**
	 * The version of this plugin.
	 *
	 * @since    1.0.0
	 * @access   private
	 * @var      string    $version    The current version of this plugin.
	 */
	private $version;

	/**
	 * The MailChimp API key
	 *
	 * @since    1.0.0
	 * @access   private
	 * @var      string    $api_key    The MailChimp API key
	 */
	private $api_key;

	/**
	 * The MailChimp list ID
	 *
	 * @since    1.0.0
	 * @access   private
	 * @var      string    $list_id    The MailChimp list ID
	 */
	private $list_id;

	/**
	 * Initialize the class and set its properties.
	 *
	 * @since    1.0.0
	 * @param      string    $plugin_name       The name of the plugin.
	 * @param      string    $version    The version of this plugin.
	 */
	public function __construct( $plugin_name, $version )
	{
		$this->plugin_name = $plugin_name;
		$this->version = $version;

		if (function_exists('env')) {
			$this->api_key = env('MAILCHIMP_API_KEY');
			$this->list_id = env('MAILCHIMP_LIST_ID');
		}
	}

	/**
	 * Register the JavaScript for the public-facing side of the site.
	 *
	 * @since    1.0.0
	 */
	public function enqueue_scripts() 
	{
		wp_enqueue_script($this->plugin_name, plugin_dir_url( __FILE__ ) . 'js/reuna-mailchimp-public.js', array( 'jquery' ), $this->version, false);

		wp_localize_script($this->plugin_name, 'wpApiSettings', [
			'root' => esc_url_raw( rest_url() ),
			'nonce' => wp_create_nonce( 'wp_rest' )
		]);
	}

	/**
	 * Register REST API routes provided by the plugin
	 *
	 * @since    1.0.0
	 */
	public function register_rest_api_routes() 
	{
		register_rest_route($this->plugin_name . '/v1', '/subscribe', [
			'methods' => 'POST',
			'callback' => [$this, 'handle_rest_api_request'],
			'permission_callback' => function () {
				return current_user_can('read');
			}
		]);
	}

	/**
	 * Subscribe user on registration
	 *
	 * @since    1.1.0
	 */
	public function handle_user_register(int $user_id)
	{
		try {
			$this->create_subscriber($user_id);
		}
		catch (\Exception $exception) {
			// TODO: log the exception
		}
	}

	/**
	 * Handle the REST API Request
	 *
	 * @since    1.0.0
	 */
	public function handle_rest_api_request(WP_REST_Request $request) 
	{
		$user_id = get_current_user_id();

		if (! $this->subscriber_exists($user_id)) {
			$this->create_subscriber($user_id);
		}

		$tags = $request->get_param('tags');
		if (! is_array($tags)) {
			return;
		}

		$this->add_subscriber_tags($user_id, $tags);
	}

	/**
	 * Check if a user is already subscribed to a list
	 *
	 * @since    1.0.0
	 */
	protected function subscriber_exists($user_id)
	{
		$user = get_userdata($user_id);

		$mailchimp =  new Mailchimp($this->api_key);
		$subscriber_hash = MailChimp::subscriberHash($user->user_email);

		$mailchimp->get('lists/' . $this->list_id . '/members/' . $subscriber_hash);

		return $mailchimp->success();
	}

	/**
	 * Add tags to an existing subscriber
	 *
	 * @since    1.0.0
	 */
	protected function add_subscriber_tags($user_id, array $tags)
	{
		$user = get_userdata($user_id);
		
		$mailchimp =  new Mailchimp($this->api_key);
		$subscriber_hash = MailChimp::subscriberHash($user->user_email);

		$existing_tags = $mailchimp->get('lists/' . $this->list_id . '/members/' . $subscriber_hash . '/tags');
		$existing_tags = array_column($existing_tags, 'name');

		$new_tags = array_values(array_unique(array_merge($existing_tags, $tags)));
		$new_tags = array_map(function($tag) {
			return [
				'name' => $tag,
				'status' => 'active',
			];
		}, $new_tags);

		return $mailchimp->post('lists/' . $this->list_id . '/members/' . $subscriber_hash . '/tags', [
			'tags' => $new_tags,
		]);
	}

	/**
	 * Subscribe user to list
	 *
	 * @since    1.0.0
	 */
	public function create_subscriber(int $user_id)
	{
		$user = get_userdata($user_id);

		$mailchimp = new Mailchimp($this->api_key);

		$options = [
			'email_address' => $user->user_email,
			'status' => 'subscribed',
			'merge_fields' => [
				'FNAME' => $user->first_name,
				'LNAME' => $user->last_name,
			],
		];

		return $mailchimp->post('lists/' . $this->list_id . '/members', $options);
	}
}