<?php
defined( 'ABSPATH' ) || exit;

class RT_WA_Analytics_Tracker {

	private $db;
	private $settings;
	private $gtm_noscript_printed = false;

	public function __construct() {
		$this->db       = RT_WA_Analytics_DB::instance();
		$this->settings = RT_WA_Analytics_Settings::instance();

		add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_tracker' ) );
		add_action( 'wp_body_open', array( $this, 'output_gtm_noscript' ), 1 );
		// Fallback for themes that never call wp_body_open(). The method is a
		// no-op once the body-open hook has printed the noscript block.
		add_action( 'wp_footer', array( $this, 'output_gtm_noscript' ), 20 );
	}

	/**
	 * Read the visitor's stored consent choice.
	 *
	 * @return string "accepted", "declined" or an empty string when not set.
	 */
	private function get_consent() {
		if ( ! isset( $_COOKIE['rt_wa_consent'] ) ) {
			return '';
		}

		return sanitize_text_field( wp_unslash( $_COOKIE['rt_wa_consent'] ) );
	}

	public function is_tracking_enabled() {
		if ( $this->settings->get( 'enable_tracking' ) !== 'yes' ) {
			return false;
		}

		if ( $this->settings->get( 'privacy_consent_enable' ) === 'yes' ) {
			$consent = $this->get_consent();
			if ( $consent === 'declined' ) {
				return false;
			}

			// Strict GDPR mode: do not process any visitor data before an
			// explicit "Accept" choice has been recorded.
			if ( $this->settings->get( 'privacy_gdpr_mode' ) === 'yes' && $consent !== 'accepted' ) {
				return false;
			}
		}

		if ( $this->settings->get( 'ignore_admin' ) === 'yes' && current_user_can( 'manage_options' ) ) {
			return false;
		}

		if ( $this->settings->get( 'ignore_logged_in' ) === 'yes' && is_user_logged_in() ) {
			return false;
		}

		$excluded_roles = $this->settings->get( 'excluded_roles', array() );
		if ( ! empty( $excluded_roles ) && is_user_logged_in() ) {
			$user = wp_get_current_user();
			foreach ( (array) $excluded_roles as $role ) {
				if ( in_array( $role, (array) $user->roles, true ) ) {
					return false;
				}
			}
		}

		$excluded_pages = $this->settings->get( 'excluded_pages', '' );
		if ( ! empty( $excluded_pages ) ) {
			$pages       = explode( "\n", $excluded_pages );
			$current_url = $this->get_current_url();
			foreach ( $pages as $page ) {
				$page = trim( $page );
				if ( ! empty( $page ) && strpos( $current_url, $page ) !== false ) {
					return false;
				}
			}
		}

		return true;
	}

	/**
	 * Whether third-party tags may be loaded or receive forwarded events for
	 * this request. When the consent banner is enabled, tagging is only
	 * allowed after the visitor has explicitly accepted.
	 *
	 * @return bool
	 */
	private function is_third_party_allowed() {
		if ( $this->settings->get( 'privacy_consent_enable' ) !== 'yes' ) {
			return true;
		}

		return $this->get_consent() === 'accepted';
	}

	/**
	 * Validated Google Tag Manager container ID.
	 *
	 * @return string Empty string when disabled or invalid.
	 */
	private function get_gtm_id() {
		if ( $this->settings->get( 'integration_gtm_enable' ) !== 'yes' ) {
			return '';
		}

		$gtm_id = strtoupper( trim( (string) $this->settings->get( 'integration_gtm_id', '' ) ) );
		if ( ! preg_match( '/^GTM-[A-Z0-9]+$/', $gtm_id ) ) {
			return '';
		}

		return $gtm_id;
	}

	public function enqueue_tracker() {
		if ( ! $this->is_tracking_enabled() ) {
			return;
		}

		$gtm_id              = $this->get_gtm_id();
		$third_party_allowed = $this->is_third_party_allowed();
		$gtm_allowed         = '' !== $gtm_id && $third_party_allowed;

		wp_enqueue_script(
			'rt-wa-analytics-tracker',
			RT_WA_ANALYTICS_URL . 'modules/tracking/js/tracker.js',
			array(),
			RT_WA_ANALYTICS_VERSION,
			array(
				'strategy'  => 'defer',
				'in_footer' => true,
			)
		);

		$tracker_data = array(
			'ajaxUrl'           => admin_url( 'admin-ajax.php' ),
			'nonce'             => wp_create_nonce( 'rt_wa_tracker_nonce' ),
			'cookieLifetime'    => (int) $this->settings->get( 'cookie_lifetime', 30 ),
			'sessionTimeout'    => (int) $this->settings->get( 'session_timeout', 30 ) * 60,
			'visitorUuid'       => $this->get_visitor_uuid(),
			'sessionId'         => $this->get_session_id(),
			'currentUrl'        => $this->get_current_url(),
			'referrer'          => isset( $_SERVER['HTTP_REFERER'] ) ? esc_url_raw( wp_unslash( $_SERVER['HTTP_REFERER'] ) ) : '',
			'debug'             => $this->settings->get( 'debug_mode' ) === 'yes',
			'maskIp'            => $this->settings->get( 'privacy_mask_ip' ) === 'yes',
			'ga4Id'             => $this->settings->get( 'integration_ga4_enable' ) === 'yes' ? $this->settings->get( 'integration_ga4_id' ) : '',
			'gtmId'             => $gtm_allowed ? $gtm_id : '',
			'metaPixelId'       => $this->settings->get( 'integration_meta_enable' ) === 'yes' ? $this->settings->get( 'integration_meta_pixel_id' ) : '',
			'metaEventName'     => $this->settings->get( 'integration_meta_event_name' ),
			'tiktokPixelId'     => $this->settings->get( 'integration_tiktok_pixel_id' ),
			'snapchatPixelId'   => $this->settings->get( 'integration_snapchat_pixel_id' ),
			'pinterestTagId'    => $this->settings->get( 'integration_pinterest_tag_id' ),
			'twitterPixelId'    => $this->settings->get( 'integration_twitter_pixel_id' ),
			'linkedinInsightId' => $this->settings->get( 'integration_linkedin_insight_id' ),
			'googleAdsId'       => $this->settings->get( 'integration_google_ads_id' ),
			'clarityProjectId'  => $this->settings->get( 'integration_clarity_project_id' ),
			'bingUetId'         => $this->settings->get( 'integration_bing_uet_id' ),
			'redditPixelId'     => $this->settings->get( 'integration_reddit_pixel_id' ),
			'quoraPixelId'      => $this->settings->get( 'integration_quora_pixel_id' ),
			'yandexMetrikaId'   => $this->settings->get( 'integration_yandex_metrika_id' ),
			'hubspotId'         => $this->settings->get( 'integration_hubspot_id' ),
			'hotjarId'          => $this->settings->get( 'integration_hotjar_id' ),
			'whatsappPatterns'  => $this->get_whatsapp_patterns(),
		);

		if ( ! $third_party_allowed ) {
			$third_party_keys = array(
				'ga4Id',
				'gtmId',
				'metaPixelId',
				'tiktokPixelId',
				'snapchatPixelId',
				'pinterestTagId',
				'twitterPixelId',
				'linkedinInsightId',
				'googleAdsId',
				'clarityProjectId',
				'bingUetId',
				'redditPixelId',
				'quoraPixelId',
				'yandexMetrikaId',
				'hubspotId',
				'hotjarId',
			);
			foreach ( $third_party_keys as $key ) {
				$tracker_data[ $key ] = '';
			}
		}

		wp_localize_script( 'rt-wa-analytics-tracker', 'rtWaTracker', $tracker_data );

		if ( $gtm_allowed ) {
			// Inline-only handle: no external file, the loader is attached with
			// the WordPress script API and printed with the footer scripts.
			wp_register_script( 'zaaecl_gtm', false, array(), ZAAECL_VERSION, true );
			wp_enqueue_script( 'zaaecl_gtm' );
			wp_add_inline_script( 'zaaecl_gtm', $this->get_gtm_loader_js( $gtm_id ) );
		}
	}

	/**
	 * Build the GTM loader snippet.
	 *
	 * @param string $gtm_id Validated GTM container ID.
	 * @return string
	 */
	private function get_gtm_loader_js( $gtm_id ) {
		return "(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!=='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+encodeURIComponent(i)+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','" . esc_js( $gtm_id ) . "');";
	}

	/**
	 * Print the GTM <noscript> fallback once, from wp_body_open() or, for
	 * themes without that hook, from wp_footer().
	 */
	public function output_gtm_noscript() {
		if ( $this->gtm_noscript_printed || ! $this->is_tracking_enabled() ) {
			return;
		}

		$gtm_id = $this->get_gtm_id();
		if ( '' === $gtm_id || ! $this->is_third_party_allowed() ) {
			return;
		}

		$this->gtm_noscript_printed = true;

		printf(
			'<noscript><iframe src="%s" height="0" width="0" style="display:none;visibility:hidden" title="%s"></iframe></noscript>',
			esc_url( 'https://www.googletagmanager.com/ns.html?id=' . rawurlencode( $gtm_id ) ),
			esc_attr__( 'Google Tag Manager', 'zaaed-click2chat' )
		);
	}

	private function get_whatsapp_patterns() {
		$raw   = $this->settings->get( 'whatsapp_link_patterns', '' );
		$lines = array_filter( array_map( 'trim', explode( "\n", $raw ) ) );
		return array_values( $lines );
	}

	private function get_visitor_uuid() {
		if ( isset( $_COOKIE['rt_wa_visitor'] ) ) {
			return sanitize_text_field( wp_unslash( $_COOKIE['rt_wa_visitor'] ) );
		}

		return $this->generate_uuid();
	}

	private function get_session_id() {
		if ( isset( $_COOKIE['rt_wa_session'] ) ) {
			return sanitize_text_field( wp_unslash( $_COOKIE['rt_wa_session'] ) );
		}

		return $this->generate_uuid();
	}

	public function generate_uuid() {
		return RT_WA_Analytics_DB::generate_uuid();
	}

	private function get_current_url() {
		$path = isset( $_SERVER['REQUEST_URI'] ) ? sanitize_text_field( wp_unslash( $_SERVER['REQUEST_URI'] ) ) : '/';
		return esc_url_raw( home_url( $path ) );
	}
}