<?php
declare( strict_types=1 );

namespace CodeBold\Redirect\Redirects;

defined( 'ABSPATH' ) || exit;

/**
 * One redirect, as stored.
 *
 * A plain value. Deciding whether it applies is the Engine's job and deciding whether it
 * may be saved is the Validator's — a row that knew how to do either would have to know
 * about WordPress, the request and the other rules, and could not be tested on its own.
 */
final class Rule {

	public const EXACT    = 'exact';
	public const WILDCARD = 'wildcard';
	public const REGEX    = 'regex';

	/** The codes a rule may use, with 410 and 451 answering in place rather than moving. */
	public const CODES = [ 301, 302, 307, 308, 410, 451 ];

	/** Codes that send the visitor somewhere. The rest answer where they are. */
	public const MOVES = [ 301, 302, 307, 308 ];

	/**
	 * Where a rule came from, so the list can say "made automatically when you renamed
	 * this page" rather than leaving somebody to wonder who added it.
	 */
	public const ORIGINS = [ 'manual', 'auto', 'post', 'trash', 'import', '404' ];

	/**
	 * @param list<array<string, mixed>> $conditions
	 */
	public function __construct(
		public int $id = 0,
		public string $source = '',
		public string $match_type = self::EXACT,
		public string $target = '',
		public string $target_type = 'url',
		public int $target_id = 0,
		public int $status_code = 301,
		public bool $case_sensitive = false,
		public bool $pass_query = true,
		public array $conditions = [],
		public ?string $starts_at = null,
		public ?string $ends_at = null,
		public bool $enabled = true,
		public int $priority = 0,
		public string $group_name = '',
		public string $note = '',
		public string $origin = 'manual',
		public int $post_id = 0,
		public int $hits = 0,
		public ?string $last_hit = null,
		public string $created_at = '',
		public string $updated_at = ''
	) {}

	/**
	 * @param object|array<string, mixed> $row
	 */
	public static function from_row( object|array $row ): self {
		$row = (array) $row;

		$conditions = json_decode( (string) ( $row['conditions'] ?? '' ), true );

		return new self(
			id: (int) ( $row['id'] ?? 0 ),
			source: (string) ( $row['source'] ?? '' ),
			match_type: (string) ( $row['match_type'] ?? self::EXACT ),
			target: (string) ( $row['target'] ?? '' ),
			target_type: (string) ( $row['target_type'] ?? 'url' ),
			target_id: (int) ( $row['target_id'] ?? 0 ),
			status_code: (int) ( $row['status_code'] ?? 301 ),
			case_sensitive: (bool) ( $row['case_sensitive'] ?? false ),
			pass_query: (bool) ( $row['pass_query'] ?? true ),
			conditions: is_array( $conditions ) ? array_values( $conditions ) : [],
			starts_at: empty( $row['starts_at'] ) ? null : (string) $row['starts_at'],
			ends_at: empty( $row['ends_at'] ) ? null : (string) $row['ends_at'],
			enabled: (bool) ( $row['enabled'] ?? true ),
			priority: (int) ( $row['priority'] ?? 0 ),
			group_name: (string) ( $row['group_name'] ?? '' ),
			note: (string) ( $row['note'] ?? '' ),
			origin: (string) ( $row['origin'] ?? 'manual' ),
			post_id: (int) ( $row['post_id'] ?? 0 ),
			hits: (int) ( $row['hits'] ?? 0 ),
			last_hit: empty( $row['last_hit'] ) ? null : (string) $row['last_hit'],
			created_at: (string) ( $row['created_at'] ?? '' ),
			updated_at: (string) ( $row['updated_at'] ?? '' )
		);
	}

	/**
	 * The columns, ready for $wpdb->insert().
	 *
	 * @return array<string, mixed>
	 */
	public function to_row(): array {
		return [
			'source'         => $this->source,
			'source_hash'    => $this->source_hash(),
			'match_type'     => $this->match_type,
			'target'         => $this->target,
			'target_type'    => $this->target_type,
			'target_id'      => $this->target_id,
			'status_code'    => $this->status_code,
			'case_sensitive' => (int) $this->case_sensitive,
			'pass_query'     => (int) $this->pass_query,
			'conditions'     => [] === $this->conditions ? null : wp_json_encode( $this->conditions ),
			'starts_at'      => $this->starts_at,
			'ends_at'        => $this->ends_at,
			'enabled'        => (int) $this->enabled,
			'priority'       => $this->priority,
			'group_name'     => $this->group_name,
			'note'           => $this->note,
			'origin'         => $this->origin,
			'post_id'        => $this->post_id,
			'hits'           => $this->hits,
			'last_hit'       => $this->last_hit,
		];
	}

	/**
	 * Only exact rules are looked up by hash. Patterns get a fixed value so that an
	 * address that happens to look like one can never collide with them.
	 */
	public function source_hash(): string {
		if ( self::EXACT !== $this->match_type ) {
			return str_repeat( '0', 32 );
		}

		return Address::parse( $this->source )->hash();
	}

	/**
	 * Text as text: control characters and line breaks out, runs of spaces collapsed,
	 * cut to length. Nothing that merely looks like HTML is touched — it is escaped where
	 * it is shown, which is the only place escaping belongs.
	 */
	public static function plain_text( string $text, int $max ): string {
		$text = (string) preg_replace( '/[\p{Cc}\p{Cf}\p{Zl}\p{Zp}]+/u', ' ', $text );
		$text = trim( (string) preg_replace( '/\s{2,}/u', ' ', $text ) );

		return mb_substr( $text, 0, $max );
	}

	public function moves(): bool {
		return in_array( $this->status_code, self::MOVES, true );
	}

	public function is_permanent(): bool {
		return in_array( $this->status_code, [ 301, 308 ], true );
	}

	public function has_condition( string $type ): bool {
		foreach ( $this->conditions as $condition ) {
			if ( ( $condition['type'] ?? '' ) === $type ) {
				return true;
			}
		}

		return false;
	}

	/** Whether the rule is in its scheduled window right now. Times are stored in UTC. */
	public function in_schedule( ?int $now = null ): bool {
		$now ??= time();

		if ( null !== $this->starts_at && strtotime( $this->starts_at . ' UTC' ) > $now ) {
			return false;
		}

		if ( null !== $this->ends_at && strtotime( $this->ends_at . ' UTC' ) <= $now ) {
			return false;
		}

		return true;
	}

	/**
	 * For the REST API and the admin screen.
	 *
	 * @return array<string, mixed>
	 */
	public function to_array(): array {
		$out = get_object_vars( $this );

		$out['target_label'] = $this->target_label();

		return $out;
	}

	/**
	 * What the list shows for "To". A linked page is named by its title, because
	 * "/?p=4471" tells nobody anything and the title is how people think of the page.
	 */
	public function target_label(): string {
		if ( 'post' === $this->target_type && $this->target_id > 0 ) {
			$title = get_the_title( $this->target_id );

			return '' === $title ? '#' . $this->target_id : html_entity_decode( $title, ENT_QUOTES, 'UTF-8' );
		}

		if ( 'term' === $this->target_type && $this->target_id > 0 ) {
			$term = get_term( $this->target_id );

			return $term instanceof \WP_Term ? $term->name : '#' . $this->target_id;
		}

		return '';
	}
}