<?php
/**
 * The preferences route: `rooster-admin/v1/prefs` (POST `key`, `product`, `value`; DELETE `key`, `product`), and
 * the feedback route (0.20.0): `rooster-admin/v1/feedback` (POST `product`, `message`, `category`, `rating`,
 * `anonymous`, `email`, `screen`: Feedback::submit(), through the product's sender). Registered on `rest_api_init` for signed-in users only (the loader's
 * rooster_admin_rest(): a visitor's REST request registers nothing), with a permission callback, a schema for the
 * arguments and each value validated by its owner. Cookie authentication carries the `wp_rest` nonce
 * (`X-WP-Nonce`, Chrome::script_data()). The registry boots the first time a request reaches a handler
 * (Library::ensure_registry()), never on `rest_api_init` itself.
 *
 * @package RoosterAdmin
 */

namespace Rooster\Admin;

defined( 'ABSPATH' ) || exit;

/**
 * Static.
 */
final class Rest {

	/**
	 * Most docked side panels a user keeps per product (0.46.0).
	 */
	public const MAX_PANELS = 40;

	/**
	 * The namespace.
	 */
	public const NAMESPACE = 'rooster-admin/v1';

	/**
	 * The route.
	 */
	public const ROUTE = '/prefs';

	/**
	 * Most hint ids remembered.
	 */
	private const MAX_HINTS = 50;

	/**
	 * Whether routes() ran.
	 *
	 * @var bool
	 */
	private static bool $registered = false;

	/**
	 * Registers the route (once per request).
	 */
	public static function routes(): void {
		if ( self::$registered ) {
			return;
		}
		self::$registered = true;
		$args             = array(
			'key'     => array(
				'type'     => 'string',
				'required' => true,
				'enum'     => array_keys( Prefs::KEYS ),
			),
			'product' => array( // no default: WordPress validates defaults against the schema too, and '' fails the pattern
				'type'    => 'string',
				'pattern' => '^[a-z0-9][a-z0-9_-]{0,39}$',
			),
			'board'   => array( // the page board a `boards` value is for (0.58.0)
				'type'    => 'string',
				'pattern' => '^[a-z0-9][a-z0-9_./-]{0,119}$',
			),
			'table'   => array( // the table a `tables` value is for (0.61.0): its DOM id (Guidance::TABLE_PATTERN; Guidance is not loaded yet here)
				'type'    => 'string',
				'pattern' => '^[A-Za-z][A-Za-z0-9_-]{0,119}$',
			),
			'panel'   => array( // the side panel a `panel_state` value is for (0.67.0): its key
				'type'    => 'string',
				'pattern' => '^[a-z0-9][a-z0-9_-]{0,39}$',
			),
			'layout'  => array( // the page's windows a `windows` value is for (0.68.13): the layout's key
				'type'    => 'string',
				'pattern' => '^[a-z0-9][a-z0-9_-]{0,39}$',
			),
		);
		register_rest_route(
			self::NAMESPACE,
			self::ROUTE,
			array(
				array(
					'methods'             => \WP_REST_Server::CREATABLE,
					'callback'            => array( self::class, 'set' ),
					'permission_callback' => array( self::class, 'permission' ),
					'args'                => $args + array(
						'value' => array(
							'type'     => array( 'string', 'array', 'object' ), // a word for the theme (0.24.0), else a list; string first, because rest_is_array() takes a plain string for a list; a board's arrangement is an object (0.58.0: rest_is_array() takes lists only); clean() decides per key
							'required' => true,
						),
					),
				),
				array(
					'methods'             => \WP_REST_Server::DELETABLE,
					'callback'            => array( self::class, 'remove' ),
					'permission_callback' => array( self::class, 'permission' ),
					'args'                => $args,
				),
			)
		);
		register_rest_route(
			self::NAMESPACE,
			'/feedback',
			array(
				'methods'             => \WP_REST_Server::CREATABLE,
				'callback'            => array( self::class, 'feedback' ),
				'permission_callback' => array( self::class, 'permission' ),
				'args'                => array(
					'product'   => array(
						'type'     => 'string',
						'required' => true,
						'pattern'  => '^[a-z0-9][a-z0-9_-]{0,39}$',
					),
					'message'   => array(
						'type'     => 'string',
						'required' => true,
					),
					'category'  => array(
						'type'    => 'string',
						'default' => 'other',
					),
					'rating'    => array(
						'type'    => 'integer',
						'default' => 0,
						'minimum' => 0,
						'maximum' => 5,
					),
					'anonymous' => array(
						'type'    => 'boolean',
						'default' => false,
					),
					'email'     => array(
						'type'    => 'string',
						'default' => '',
					),
					'screen'    => array(
						'type'    => 'string',
						'default' => '',
					),
				),
			)
		);
	}

	/**
	 * POST /feedback (0.20.0): the brand bar's feedback dialog, through the product's sender (Feedback::submit()).
	 * The registry boots here, for the product and its sender.
	 *
	 * @param \WP_REST_Request $request The request.
	 * @return \WP_REST_Response|\WP_Error
	 */
	public static function feedback( \WP_REST_Request $request ) {
		$registry = Library::ensure_registry();
		$input    = array();
		foreach ( array( 'message', 'category', 'rating', 'anonymous', 'email', 'screen' ) as $field ) {
			$input[ $field ] = $request->get_param( $field );
		}
		$result = Feedback::submit( $registry, (string) $request['product'], $input );
		if ( is_wp_error( $result ) ) {
			return $result;
		}
		$response = rest_ensure_response( $result );
		$response->header( 'Cache-Control', 'no-store' );
		return $response;
	}

	/**
	 * Forgets that routes() ran (tests, where one process serves many requests).
	 *
	 * @internal
	 */
	public static function reset(): void {
		self::$registered = false;
	}

	/**
	 * The permission: a signed-in user who can read (cookie authentication has checked the nonce by now).
	 */
	public static function permission(): bool {
		return is_user_logged_in() && current_user_can( 'read' );
	}

	/**
	 * POST: stores one preference.
	 *
	 * @param \WP_REST_Request $request The request.
	 * @return \WP_REST_Response|\WP_Error
	 */
	public static function set( \WP_REST_Request $request ) {
		$result = self::save( (string) $request['key'], (string) $request['product'], $request['value'], self::item( $request ) );
		return is_wp_error( $result ) ? $result : rest_ensure_response( $result );
	}

	/**
	 * The item a value is for: a table's id (`tables`), a panel's key (`panel_state`, 0.67.0), a layout's key
	 * (`windows`, 0.68.13), else a board's key.
	 *
	 * @param \WP_REST_Request $request The request.
	 */
	private static function item( \WP_REST_Request $request ): string {
		$key = (string) $request['key'];
		if ( Prefs::WINDOWS === $key ) {
			return (string) $request['layout'];
		}
		return (string) ( Prefs::TABLES === $key || Prefs::TEXT_SIZES === $key ? $request['table'] : ( Prefs::PANEL_STATE === $key ? $request['panel'] : $request['board'] ) );
	}

	/**
	 * DELETE: removes one preference (one board's arrangement, for `boards`).
	 *
	 * @param \WP_REST_Request $request The request.
	 * @return \WP_REST_Response|\WP_Error
	 */
	public static function remove( \WP_REST_Request $request ) {
		$result = self::save( (string) $request['key'], (string) $request['product'], null, self::item( $request ) );
		return is_wp_error( $result ) ? $result : rest_ensure_response( $result );
	}

	/**
	 * Validates and stores one preference (null removes it). The result: key, product, value. A `boards` value is one
	 * board's arrangement (0.58.0): stored under `$board` among the product's others (Board::store()), the result its
	 * own with the board's key. A `tables` value (0.61.0) is one table's shown columns, stored the same way under the
	 * table's id (Guidance::store()), the result with the table's id.
	 *
	 * @param string $key     Preference key (Prefs::KEYS).
	 * @param string $product Product slug ('' for a key that is not per product).
	 * @param mixed  $value   The decoded value, or null to remove.
	 * @param string $board   The page board (`boards`), or the table's id (`tables`).
	 * @return array<string, mixed>|\WP_Error
	 */
	public static function save( string $key, string $product, $value, string $board = '' ) {
		$user = get_current_user_id();
		if ( $user <= 0 ) {
			return new \WP_Error( 'rooster_admin_forbidden', __( 'You must be signed in.', 'ai-eshop-optimizer' ), array( 'status' => 401 ) );
		}
		$key     = sanitize_key( $key );
		$product = sanitize_key( $product );
		if ( ! isset( Prefs::KEYS[ $key ] ) ) {
			return new \WP_Error( 'rooster_admin_key', __( 'Unknown preference.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
		}
		$registry = Library::ensure_registry();
		$per      = Prefs::KEYS[ $key ];
		$def      = $per ? $registry->product( $product ) : null;
		if ( $per && null === $def ) {
			return new \WP_Error( 'rooster_admin_product', __( 'Unknown product.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
		}
		if ( null !== $value ) {
			if ( strlen( (string) wp_json_encode( $value ) ) > ( Prefs::BOARDS === $key ? Board::VALUE_BYTES : Prefs::MAX_BYTES ) ) { // 0.80.0: a board's rows and layouts with it
				return new \WP_Error( 'rooster_admin_value', __( 'The value is too large.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
			}
			$value = self::clean( $registry, $key, $value, $def );
			if ( null === $value ) {
				return new \WP_Error( 'rooster_admin_value', __( 'The value is not acceptable.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
			}
		}
		if ( Prefs::BOARDS === $key ) {
			if ( 1 !== preg_match( Board::KEY_PATTERN, $board ) ) {
				return new \WP_Error( 'rooster_admin_board', __( 'Unknown board.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
			}
			$layout = $value;
			$boards = Board::store( Prefs::get( $user, Prefs::BOARDS, $product, array() ), $board, $layout );
			if ( ! Prefs::set( $user, $key, array() === $boards ? null : $boards, $product ) ) {
				return new \WP_Error( 'rooster_admin_save', __( 'That was not saved. Try again.', 'ai-eshop-optimizer' ), array( 'status' => 500 ) );
			}
			return array(
				'key'     => $key,
				'product' => $product,
				'board'   => $board,
				'value'   => $layout,
			);
		}
		if ( Prefs::TEXT_SIZES === $key ) { // 0.68.0: one table's text size among the product's others; the default forgets it
			if ( 1 !== preg_match( '/^[A-Za-z][A-Za-z0-9_-]{0,119}$/', $board ) ) {
				return new \WP_Error( 'rooster_admin_table', __( 'Unknown table.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
			}
			$sizes = (array) Prefs::get( $user, Prefs::TEXT_SIZES, $product, array() );
			unset( $sizes[ $board ] );
			if ( null !== $value && 3 !== $value ) {
				$sizes[ $board ] = $value;
			}
			while ( count( $sizes ) > 1 && strlen( (string) wp_json_encode( $sizes ) ) > Prefs::LIMITS[ Prefs::TEXT_SIZES ] ) {
				array_shift( $sizes );
			}
			if ( ! Prefs::set( $user, $key, array() === $sizes ? null : $sizes, $product ) ) {
				return new \WP_Error( 'rooster_admin_save', __( 'That was not saved. Try again.', 'ai-eshop-optimizer' ), array( 'status' => 500 ) );
			}
			return array(
				'key'     => $key,
				'product' => $product,
				'table'   => $board,
				'value'   => $value,
			);
		}
		if ( Prefs::PANEL_STATE === $key ) { // 0.67.0: one panel's state among the product's others
			if ( 1 !== preg_match( '/^[a-z0-9][a-z0-9_-]{0,39}$/', $board ) ) {
				return new \WP_Error( 'rooster_admin_panel', __( 'Unknown panel.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
			}
			$panels = (array) Prefs::get( $user, Prefs::PANEL_STATE, $product, array() );
			unset( $panels[ $board ] );
			if ( null !== $value ) {
				$panels[ $board ] = $value; // the panel saved last at the end
			}
			while ( count( $panels ) > 1 && strlen( (string) wp_json_encode( $panels ) ) > Prefs::LIMITS[ Prefs::PANEL_STATE ] ) {
				array_shift( $panels );
			}
			if ( ! Prefs::set( $user, $key, array() === $panels ? null : $panels, $product ) ) {
				return new \WP_Error( 'rooster_admin_save', __( 'That was not saved. Try again.', 'ai-eshop-optimizer' ), array( 'status' => 500 ) );
			}
			return array(
				'key'     => $key,
				'product' => $product,
				'panel'   => $board,
				'value'   => $value,
			);
		}
		if ( Prefs::WINDOWS === $key ) { // 0.68.13: one layout's windows among the product's others
			if ( 1 !== preg_match( '/^[a-z0-9][a-z0-9_-]{0,39}$/', $board ) ) {
				return new \WP_Error( 'rooster_admin_layout', __( 'Unknown layout.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
			}
			$layouts = (array) Prefs::get( $user, Prefs::WINDOWS, $product, array() );
			unset( $layouts[ $board ] );
			if ( null !== $value ) {
				$layouts[ $board ] = $value; // the layout saved last at the end
			}
			while ( count( $layouts ) > 1 && strlen( (string) wp_json_encode( $layouts ) ) > Prefs::LIMITS[ Prefs::WINDOWS ] ) {
				array_shift( $layouts );
			}
			if ( ! Prefs::set( $user, $key, array() === $layouts ? null : $layouts, $product ) ) {
				return new \WP_Error( 'rooster_admin_save', __( 'That was not saved. Try again.', 'ai-eshop-optimizer' ), array( 'status' => 500 ) );
			}
			return array(
				'key'     => $key,
				'product' => $product,
				'layout'  => $board,
				'value'   => $value,
			);
		}
		if ( Prefs::TABLES === $key ) {
			if ( 1 !== preg_match( Guidance::TABLE_PATTERN, $board ) ) {
				return new \WP_Error( 'rooster_admin_table', __( 'Unknown table.', 'ai-eshop-optimizer' ), array( 'status' => 400 ) );
			}
			$tables = Guidance::store( (array) Prefs::get( $user, Prefs::TABLES, $product, array() ), $board, $value );
			if ( ! Prefs::set( $user, $key, array() === $tables ? null : $tables, $product ) ) {
				return new \WP_Error( 'rooster_admin_save', __( 'That was not saved. Try again.', 'ai-eshop-optimizer' ), array( 'status' => 500 ) );
			}
			return array(
				'key'     => $key,
				'product' => $product,
				'table'   => $board,
				'value'   => $value,
			);
		}
		if ( ! Prefs::set( $user, $key, $value, $per ? $product : null ) ) {
			return new \WP_Error( 'rooster_admin_save', __( 'That was not saved. Try again.', 'ai-eshop-optimizer' ), array( 'status' => 500 ) );
		}
		return array(
			'key'     => $key,
			'product' => $per ? $product : '',
			'value'   => $value,
		);
	}

	/**
	 * A validated value, or null.
	 *
	 * @param Registry                  $registry The registry.
	 * @param string                    $key      Preference key.
	 * @param mixed                     $value    Decoded value.
	 * @param array<string, mixed>|null $product  The product (per-product keys).
	 * @return mixed
	 */
	public static function clean( Registry $registry, string $key, $value, ?array $product ) {
		switch ( $key ) {
			case Prefs::PINS:
				if ( ! is_array( $value ) || count( $value ) > Chrome::MAX_PINS ) {
					return null;
				}
				$visible = $registry->visible( $product['slug'] );
				$out     = array();
				foreach ( $value as $id ) {
					if ( ! is_string( $id ) || ! isset( $visible[ $id ] ) || ! $visible[ $id ]['available'] || ! $visible[ $id ]['pin'] || in_array( $id, $out, true ) ) {
						return null;
					}
					$out[] = $id;
				}
				return $out;
			case Prefs::LAYOUT:
				return HomePage::clean_layout( $value, array_keys( $product['sections'] ) );
			case Prefs::BOARDS:
				return Board::clean( $value ); // the shape; the cards are checked when the board is drawn

			case Prefs::AUDIENCES:
				if ( ! is_array( $value ) ) {
					return null;
				}
				$clean = Personas::clean( $product, $value );
				return count( $clean ) === count( $value ) ? $clean : null;
			case Prefs::THEME:
				return is_string( $value ) && in_array( $value, Prefs::THEMES, true ) ? $value : null;
			case Prefs::GUIDANCE: // a plain word, as the theme (0.61.0)
				return is_string( $value ) && in_array( $value, Prefs::GUIDANCE_LEVELS, true ) ? $value : null;
			case Prefs::TABLES:
				return Guidance::clean_shown( $value ); // a list of column keys; the table's own columns are checked when it is drawn
			case Prefs::PANEL_STATE:
				return Prefs::clean_panel( $value ); // one panel's (0.67.0)
			case Prefs::WINDOWS:
				return Prefs::clean_windows( $value ); // one layout's windows (0.68.13)
			case Prefs::TEXT_SIZES: // one table's level (0.68.0)
				return is_numeric( $value ) && isset( Prefs::TEXT_SIZE_LEVELS[ (int) $value ] ) && (float) $value === (float) (int) $value ? (int) $value : null;
			case Prefs::PANELS:
				if ( ! is_array( $value ) || count( $value ) > self::MAX_PANELS ) {
					return null;
				}
				$out = array();
				foreach ( $value as $panel ) {
					if ( ! is_string( $panel ) || 1 !== preg_match( '/^[a-z0-9][a-z0-9_-]{0,39}$/', $panel ) || in_array( $panel, $out, true ) ) {
						return null;
					}
					$out[] = $panel;
				}
				return $out;
			case Prefs::HINTS:
				if ( ! is_array( $value ) || count( $value ) > self::MAX_HINTS ) {
					return null;
				}
				$out = array();
				foreach ( $value as $hint ) {
					if ( ! is_string( $hint ) || 1 !== preg_match( '/^[a-z0-9][a-z0-9_\/.-]{0,59}$/', $hint ) || in_array( $hint, $out, true ) ) {
						return null;
					}
					$out[] = $hint;
				}
				return $out;
		}
		return null;
	}
}