<?php
/** Privacy defaults and authenticated configuration. */
namespace Accessibility_Audio_TTS\Core;

if ( ! defined( 'ABSPATH' ) ) { exit; }

class Privacy_Settings {

	public static function defaults() {
		$language = preg_match( '/^(pl|de|es)(?:[_-]|$)/i', get_locale(), $matches ) ? strtolower( $matches[1] ) : 'en';
		return array(
			'analytics_enabled' => false,
			'analytics_mode' => 'off',
			'ga4_enabled' => false,
			'ga4_transport' => 'gtag',
			'ga4_measurement_id' => '',
			'analytics_retention_days' => 365,
			'delete_audio_on_post_delete' => true,
			'backup_retention_days' => 30,
			'allow_restricted_content' => false,
			'documentation_language' => $language,
		);
	}

	/** Accept the documented WordPress/import representations, never arbitrary truthy values. */
	public static function enabled( $value ) {
		return in_array( $value, array( true, 1, '1' ), true );
	}

	public static function openai_enabled() {
		return self::enabled( get_option( 'accessibility_audio_tts_chatgpt_enabled', '0' ) );
	}

	public static function can_process_post( $post ) {
		return ! Audio_Access::is_restricted( $post ) || self::get( 'allow_restricted_content' );
	}

	public static function get( $key ) {
		$defaults = self::defaults();
		if ( ! array_key_exists( $key, $defaults ) ) { return null; }
		if ( 'analytics_mode' === $key ) {
			$mode = get_option( 'accessibility_audio_tts_privacy_analytics_mode', null );
			if ( null === $mode ) {
				// An upgrade must never turn previously consented measurement into consent-free collection.
				return self::enabled( get_option( 'accessibility_audio_tts_privacy_analytics_enabled', false ) ) ? 'consented' : 'off';
			}
			return in_array( $mode, array( 'off', 'anonymous', 'consented' ), true ) ? $mode : 'off';
		}
		if ( 'analytics_enabled' === $key ) { return 'off' !== self::get( 'analytics_mode' ); }
		if ( 'ga4_transport' === $key ) {
			return 'datalayer' === get_option( 'accessibility_audio_tts_privacy_ga4_transport', 'gtag' ) ? 'datalayer' : 'gtag';
		}
		if ( 'ga4_measurement_id' === $key ) {
			$id = get_option( 'accessibility_audio_tts_privacy_ga4_measurement_id', '' );
			return is_string( $id ) && preg_match( '/^G-[A-Z0-9]{4,20}$/D', $id ) ? $id : '';
		}
		if ( 'ga4_enabled' === $key ) {
			return 'consented' === self::get( 'analytics_mode' )
				&& self::enabled( get_option( 'accessibility_audio_tts_privacy_ga4_enabled', false ) )
				&& ( 'datalayer' === self::get( 'ga4_transport' ) || '' !== self::get( 'ga4_measurement_id' ) );
		}
		// Retention, deletion and site language are policies, not saved preferences.
		if ( 'allow_restricted_content' !== $key ) { return $defaults[ $key ]; }
		return self::enabled( get_option( 'accessibility_audio_tts_privacy_' . $key, $defaults[ $key ] ) );
	}

	public static function all() {
		$settings = array();
		foreach ( self::defaults() as $key => $value ) { $settings[ $key ] = self::get( $key ); }
		return $settings;
	}

	public static function init() {
		add_action( 'wp_ajax_accessibility_audio_tts_save_privacy', array( __CLASS__, 'save_ajax' ) );
		add_action( 'admin_init', array( '\\Accessibility_Audio_TTS\\Core\\Privacy_Documentation', 'register_policy_text' ) );
		add_action( 'admin_enqueue_scripts', array( __CLASS__, 'enqueue_admin' ) );
	}

	public static function enqueue_admin() {
		if ( ! isset( $_GET['page'] ) || 'accessibility-audio-tts' !== $_GET['page'] ) { return; }
		wp_enqueue_script( 'accessibility-audio-tts-privacy-settings', ACCESSIBILITY_AUDIO_TTS_ASSETS_URL . 'admin/ui/components/privacy-settings.min.js', array(), ACCESSIBILITY_AUDIO_TTS_VERSION, true );
		wp_localize_script( 'accessibility-audio-tts-privacy-settings', 'aatPrivacySettings', array(
			'ajaxUrl' => admin_url( 'admin-ajax.php' ), 'nonce' => wp_create_nonce( 'accessibility_audio_tts_privacy' ),
			'saved' => __( 'Privacy settings saved. The policy text below now reflects these settings.', 'accessibility-audio-tts-text-to-speech-for-articles' ),
			'error' => __( 'Privacy settings could not be saved. Please retry.', 'accessibility-audio-tts-text-to-speech-for-articles' ),
			'copied' => __( 'Copied.', 'accessibility-audio-tts-text-to-speech-for-articles' ),
			'copyFallback' => __( 'Select the text and copy it manually.', 'accessibility-audio-tts-text-to-speech-for-articles' ),
			'unsaved' => __( 'Save privacy settings to refresh the policy text before copying it.', 'accessibility-audio-tts-text-to-speech-for-articles' ),
		) );
	}

	public static function save_ajax() {
		if ( ! current_user_can( 'manage_options' ) ) { wp_send_json_error( array( 'message' => 'Access denied.' ), 403 ); return; }
		if ( ! check_ajax_referer( 'accessibility_audio_tts_privacy', 'nonce', false ) ) { wp_send_json_error( array( 'message' => 'Invalid security token.' ), 403 ); return; }
		if ( 'POST' !== ( $_SERVER['REQUEST_METHOD'] ?? '' ) ) { wp_send_json_error( array( 'message' => 'POST required.' ), 405 ); return; }
		$input = isset( $_POST['settings'] ) && is_array( $_POST['settings'] ) ? wp_unslash( $_POST['settings'] ) : array();
		$validated = array();
		foreach ( array( 'analytics_enabled', 'allow_restricted_content' ) as $key ) {
			if ( ! array_key_exists( $key, $input ) || ! is_scalar( $input[ $key ] ) ) { wp_send_json_error( array( 'message' => 'Incomplete privacy settings.' ), 400 ); return; }
			$value = $input[ $key ];
			if ( ! in_array( $value, array( '0', '1', 0, 1, false, true ), true ) ) { wp_send_json_error( array( 'message' => 'Invalid privacy toggle.' ), 400 ); return; }
			$validated[ $key ] = self::enabled( $value ) ? '1' : '0';
		}
		$mode = $input['analytics_mode'] ?? ( '1' === $validated['analytics_enabled'] ? 'consented' : 'off' );
		if ( ! is_string( $mode ) || ! in_array( $mode, array( 'off', 'anonymous', 'consented' ), true ) ) { wp_send_json_error( array( 'message' => 'Invalid analytics mode.' ), 400 ); return; }
		// The explicit mode is authoritative; keep the historical switch for portable backups.
		$validated['analytics_mode'] = $mode;
		$validated['analytics_enabled'] = 'off' === $mode ? '0' : '1';
		$ga_enabled = $input['ga4_enabled'] ?? '0';
		$transport = $input['ga4_transport'] ?? 'gtag';
		$id = $input['ga4_measurement_id'] ?? '';
		if ( ! in_array( $ga_enabled, array( '0', '1', 0, 1, false, true ), true ) || ! is_string( $transport ) || ! in_array( $transport, array( 'gtag', 'datalayer' ), true ) || ! is_string( $id ) ) { wp_send_json_error( array( 'message' => 'Invalid analytics integration settings.' ), 400 ); return; }
		$id = strtoupper( trim( $id ) );
		$ga_enabled = 'consented' === $mode && self::enabled( $ga_enabled );
		if ( '' !== $id && ! preg_match( '/^G-[A-Z0-9]{4,20}$/D', $id ) ) {
			if ( $ga_enabled && 'gtag' === $transport ) { wp_send_json_error( array( 'message' => 'Invalid GA4 measurement ID.' ), 400 ); return; }
			$id = ''; // An abandoned, hidden destination must not prevent disabling measurement.
		}
		if ( $ga_enabled && 'gtag' === $transport && '' === $id ) { wp_send_json_error( array( 'message' => 'A GA4 measurement ID is required for Google tag events.' ), 400 ); return; }
		$validated['ga4_transport'] = $transport;
		$validated['ga4_measurement_id'] = $id;
		// Disable delivery first so a partial save cannot send to an old destination.
		update_option( 'accessibility_audio_tts_privacy_ga4_enabled', '0', false );
		if ( '0' !== (string) get_option( 'accessibility_audio_tts_privacy_ga4_enabled' ) ) { wp_send_json_error( array( 'message' => 'Privacy settings were not fully saved. Reload and retry.' ), 500 ); return; }
		$validated['ga4_enabled'] = $ga_enabled ? '1' : '0';
		foreach ( $validated as $key => $value ) {
			$option = 'accessibility_audio_tts_privacy_' . $key;
			update_option( $option, $value, false );
			if ( (string) get_option( $option ) !== (string) $value ) { wp_send_json_error( array( 'message' => 'Privacy settings were not fully saved. Reload and retry.' ), 500 ); return; }
		}
		wp_send_json_success( array( 'settings' => self::all(), 'documents' => Privacy_Documentation::texts(), 'inventory' => Privacy_Documentation::storage_inventory() ) );
	}
}