<?php
/**
 * Plugin settings: defaults, reading and sanitizing.
 *
 * @package FullSession
 */

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

/**
 * All settings are stored in one option, `fullsession_settings`.
 */
class FullSession_Settings {

	const OPTION = 'fullsession_settings';

	/**
	 * WP Consent API categories a site can pick for FullSession.
	 */
	const CONSENT_CATEGORIES = array( 'statistics', 'marketing' );

	/**
	 * Default values for every setting.
	 *
	 * @return array
	 */
	public static function defaults() {
		return array(
			'customer_id'              => '',
			'enabled'                  => true,
			'excluded_roles'           => array( 'administrator', 'editor' ),
			'excluded_urls'            => '',
			'consent_mode'             => 'off',
			'consent_category'         => 'statistics',
			'identify_users'           => false,
			'identify_send_name_email' => false,
			'woo_events'               => false,
		);
	}

	/**
	 * Saved settings merged with the defaults.
	 *
	 * @return array
	 */
	public static function get() {
		$saved = get_option( self::OPTION, array() );
		if ( ! is_array( $saved ) ) {
			$saved = array();
		}
		return array_merge( self::defaults(), $saved );
	}

	/**
	 * Whether a customer ID is saved.
	 *
	 * @return bool
	 */
	public static function is_connected() {
		$settings = self::get();
		return '' !== $settings['customer_id'];
	}

	/**
	 * Customer IDs look like `cus_` followed by letters, numbers, `_` or `-`, max 45 chars.
	 *
	 * @param string $customer_id Customer ID.
	 * @return bool
	 */
	public static function is_valid_customer_id( $customer_id ) {
		return 1 === preg_match( '/^cus_[A-Za-z0-9_-]{1,41}$/', $customer_id );
	}

	/**
	 * Sanitize callback for register_setting().
	 *
	 * @param mixed $input Raw form values.
	 * @return array
	 */
	public static function sanitize( $input ) {
		$current = self::get();
		$input   = is_array( $input ) ? $input : array();
		$clean   = self::defaults();

		$customer_id = isset( $input['customer_id'] ) ? trim( sanitize_text_field( $input['customer_id'] ) ) : '';
		if ( '' === $customer_id || self::is_valid_customer_id( $customer_id ) ) {
			$clean['customer_id'] = $customer_id;
		} else {
			$clean['customer_id'] = $current['customer_id'];
			add_settings_error(
				self::OPTION,
				'fullsession_invalid_customer_id',
				__( 'That customer ID doesn\'t look right. It should start with "cus_". Your previous customer ID was kept.', 'fullsession' )
			);
		}

		$clean['enabled'] = ! empty( $input['enabled'] );

		$valid_roles             = array_keys( wp_roles()->get_names() );
		$roles                   = isset( $input['excluded_roles'] ) ? (array) $input['excluded_roles'] : array();
		$roles                   = array_map( 'sanitize_key', $roles );
		$clean['excluded_roles'] = array_values( array_intersect( $roles, $valid_roles ) );

		$urls                   = isset( $input['excluded_urls'] ) ? sanitize_textarea_field( $input['excluded_urls'] ) : '';
		$clean['excluded_urls'] = implode( "\n", self::parse_url_patterns( $urls ) );

		$clean['consent_mode'] = ( isset( $input['consent_mode'] ) && 'wp_consent_api' === $input['consent_mode'] ) ? 'wp_consent_api' : 'off';

		$category                  = isset( $input['consent_category'] ) ? sanitize_key( $input['consent_category'] ) : 'statistics';
		$clean['consent_category'] = in_array( $category, self::CONSENT_CATEGORIES, true ) ? $category : 'statistics';

		$clean['identify_users']           = ! empty( $input['identify_users'] );
		$clean['identify_send_name_email'] = ! empty( $input['identify_send_name_email'] );
		$clean['woo_events']               = ! empty( $input['woo_events'] );

		return $clean;
	}

	/**
	 * Turn the URL patterns textarea into a clean list of paths.
	 *
	 * Full URLs are reduced to their path, and every pattern starts with `/`.
	 *
	 * @param string $text One pattern per line.
	 * @return string[]
	 */
	public static function parse_url_patterns( $text ) {
		$patterns = array();
		foreach ( preg_split( '/\r\n|\r|\n/', (string) $text ) as $line ) {
			$line = trim( $line );
			if ( '' === $line ) {
				continue;
			}
			if ( false !== strpos( $line, '://' ) ) {
				$path = wp_parse_url( $line, PHP_URL_PATH );
				$line = $path ? $path : '/';
			}
			if ( '/' !== $line[0] ) {
				$line = '/' . $line;
			}
			$patterns[] = $line;
		}
		return array_values( array_unique( $patterns ) );
	}

	/**
	 * Whether a request path matches one of the patterns. `*` matches anything.
	 *
	 * @param string   $path     Request path, e.g. `/shop/item`.
	 * @param string[] $patterns Patterns from parse_url_patterns().
	 * @return bool
	 */
	public static function path_matches( $path, $patterns ) {
		$path = self::normalize_path( $path );
		foreach ( $patterns as $pattern ) {
			$regex = '#^' . str_replace( '\*', '.*', preg_quote( self::normalize_path( $pattern ), '#' ) ) . '$#i';
			if ( 1 === preg_match( $regex, $path ) ) {
				return true;
			}
		}
		return false;
	}

	/**
	 * Drop the trailing slash so `/about` and `/about/` are treated the same.
	 *
	 * @param string $path Path.
	 * @return string
	 */
	private static function normalize_path( $path ) {
		$path = '/' . ltrim( (string) $path, '/' );
		return '/' === $path ? $path : untrailingslashit( $path );
	}
}