<?php

namespace Glovario\Rest;

use Glovario\Domain\BuiltinVariables;
use Glovario\Domain\Renderer;
use Glovario\Domain\TokenParser;
use Glovario\Repository\VariableRepository;

defined( 'ABSPATH' ) || exit;

final class VariablesController {
	private $repository;
	private $renderer;
	private $builtins;

	public function __construct( VariableRepository $repository, Renderer $renderer, ?BuiltinVariables $builtins = null ) {
		$this->repository = $repository;
		$this->renderer   = $renderer;
		$this->builtins   = $builtins ? $builtins : new BuiltinVariables();
	}

	public function register() {
		add_action( 'rest_api_init', array( $this, 'routes' ) );
		add_action( 'enqueue_block_editor_assets', array( $this, 'settings' ) );
	}

	public function routes() {
		register_rest_route(
			'glovario/v1',
			'/variables',
			array(
				'methods'             => 'GET',
				'callback'            => array( $this, 'index' ),
				'permission_callback' => static function () {
					return current_user_can( 'edit_posts' );
				},
				'args'                => array(
					'search'   => array(
						'sanitize_callback' => 'sanitize_text_field',
						'default'           => '',
					),
					'include'  => array(
						'sanitize_callback' => 'sanitize_key',
						'default'           => '',
					),
					'per_page' => array(
						'sanitize_callback' => 'absint',
						'default'           => 100,
						'minimum'           => 1,
						'maximum'           => 100,
					),
				),
			)
		);
		register_rest_route(
			'glovario/v1',
			'/preview',
			array(
				'methods'             => 'POST',
				'callback'            => array( $this, 'preview' ),
				'permission_callback' => static function () {
					return current_user_can( 'edit_posts' );
				},
				'args'                => array(
					'texts'   => array(
						'type'     => 'array',
						'items'    => array( 'type' => 'string' ),
						'required' => true,
					),
					'post_id' => array(
						'sanitize_callback' => 'absint',
						'default'           => 0,
					),
				),
			)
		);
	}

	/**
	 * Plain-text previews for builder canvases that show widget text as typed
	 * (Elementor 4's atomic widgets): every Site Variable shortcode and token
	 * is replaced with its current value in the site language. Images become
	 * their alternative text. Unknown keys keep the shortcode's fallback, or the
	 * original text so the editor still sees what was typed.
	 *
	 * @param \WP_REST_Request $request Request with texts (up to 50) and post_id.
	 * @return \WP_REST_Response
	 */
	public function preview( $request ) {
		$texts   = array_slice( (array) $request->get_param( 'texts' ), 0, 50 );
		$post_id = absint( $request->get_param( 'post_id' ) );
		// A post the user cannot edit gives no context (its rules could reveal it).
		if ( $post_id && ! current_user_can( 'edit_post', $post_id ) ) {
			$post_id = 0;
		}
		$context = array(
			'post_id' => $post_id,
			'locale'  => get_locale(),
			'source'  => 'editor_preview',
		);
		return rest_ensure_response(
			array_map(
				function ( $text ) use ( $context ) {
					return $this->preview_text( substr( is_string( $text ) ? $text : '', 0, 5000 ), $context );
				},
				array_values( $texts )
			)
		);
	}

	private function preview_text( $text, $context ) {
		$value = static function ( $key, $original, $extra = array() ) use ( $context ) {
			$resolved = \Glovario\Plugin::instance()->resolver()->resolve( $key, array_merge( $context, $extra ) );
			return $resolved ? Renderer::text( $resolved['value'], $resolved['variable']['type'] ) : $original;
		};
		if ( false !== strpos( $text, '[glvr' ) ) {
			$replaced = preg_replace_callback(
				'/' . get_shortcode_regex( array( 'glvr' ) ) . '/',
				static function ( $matches ) use ( $value ) {
					if ( '[' === $matches[1] && ']' === $matches[6] ) {
						return substr( $matches[0], 1, -1 );
					}
					$attributes = shortcode_parse_atts( $matches[3] );
					$attributes = is_array( $attributes ) ? $attributes : array();
					$extra      = isset( $attributes['format'] ) ? array( 'date_format' => BuiltinVariables::sanitize_date_format( $attributes['format'] ) ) : array();
					return $value( sanitize_key( $attributes['key'] ?? '' ), $attributes['fallback'] ?? $matches[0], $extra );
				},
				$text
			);
			$text = null === $replaced ? $text : $replaced;
		}
		return ( new TokenParser() )->replace(
			$text,
			static function ( $key, $original, $date_format ) use ( $value ) {
				return $value( $key, $original, array( 'date_format' => $date_format ) );
			}
		);
	}

	public function index( $request = null ) {
		$search   = $request instanceof \WP_REST_Request ? sanitize_text_field( $request->get_param( 'search' ) ) : '';
		$include  = $request instanceof \WP_REST_Request ? sanitize_key( $request->get_param( 'include' ) ) : '';
		$per_page = $request instanceof \WP_REST_Request ? min( 100, max( 1, absint( $request->get_param( 'per_page' ) ) ) ) : 100;
		$variables = array_values(
			array_filter(
				$this->builtins->all(),
				static function ( $variable ) use ( $search, $include ) {
					if ( $include === $variable['variable_key'] || '' === $search ) {
						return true;
					}
					$haystack = implode( ' ', array( $variable['label'], $variable['variable_key'], $variable['value'], $variable['description'] ) );
					return false !== stripos( $haystack, $search );
				}
			)
		);
		// The site's own variables first: they are picked far more often than the built-ins.
		$variables = array_merge(
			$this->repository->all(
				array(
					'number' => $per_page,
					'search' => $search,
				)
			),
			array_slice( $variables, 0, $per_page )
		);
		if ( $include && ! in_array( $include, wp_list_pluck( $variables, 'variable_key' ), true ) ) {
			$selected = $this->builtins->find_by_key( $include );
			if ( ! $selected ) {
				$selected = $this->repository->find_by_key( $include );
			}
			if ( $selected ) {
				$variables[] = $selected;
			}
		}

		/**
		 * Filters the variables offered by the block editor selector.
		 *
		 * @param array  $variables Variable rows.
		 * @param string $search    Search text.
		 * @param string $include   Key that must be included when it exists.
		 * @param int    $per_page  Maximum number of site variables.
		 */
		$variables = apply_filters( 'glovario_rest_variables', $variables, $search, $include, $per_page );

		return rest_ensure_response(
			array_map(
				static function ( $variable ) {
					return array(
						'key'   => $variable['variable_key'],
						'label' => $variable['label'],
						'type'  => $variable['type'],
						'category' => $variable['category_name'] ?? __( 'Uncategorized', 'glovario' ),
						'builtin' => ! empty( $variable['builtin'] ),
						'value'    => wp_html_excerpt( Renderer::text( $variable['value'] ?? '', $variable['type'] ), 80, '…' ),
					);
				},
				$variables
			)
		);
	}

	public function settings() {
		wp_add_inline_script(
			'glovario-site-variable-editor-script',
			'window.glovarioBlockSettings = ' . wp_json_encode(
				array(
					'canManage' => current_user_can( 'manage_options' ),
					'manageUrl' => admin_url( 'admin.php?page=glovario' ),
					'createUrl' => admin_url( 'admin.php?page=glovario&action=add' ),
					'dateFormats' => $this->builtins->date_format_options(),
				)
			) . ';',
			'before'
		);
	}
}