<?php
namespace Admirly\Domain;

/**
 * Settings-driven field definitions (roles and the optional sub-field). Pure PHP.
 */
final class FieldConfig {
	public const DEFAULTS = [
		'roles' => [],
		'sub'   => [
			'enabled'  => false,
			'label'    => '',
			'options'  => [],
			'roles'    => [],
			'required' => false,
		],
	];

	private const TRANSLIT = [
		'ç' => 'c',
		'ğ' => 'g',
		'ı' => 'i',
		'ö' => 'o',
		'ş' => 's',
		'ü' => 'u',
		'Ç' => 'c',
		'Ğ' => 'g',
		'İ' => 'i',
		'Ö' => 'o',
		'Ş' => 's',
		'Ü' => 'u',
		'ä' => 'a',
		'Ä' => 'a',
		'ß' => 'ss',
		'é' => 'e',
		'è' => 'e',
		'ê' => 'e',
		'ë' => 'e',
		'É' => 'e',
		'È' => 'e',
		'à' => 'a',
		'â' => 'a',
		'À' => 'a',
		'î' => 'i',
		'ï' => 'i',
		'ô' => 'o',
		'û' => 'u',
		'ù' => 'u',
		'ñ' => 'n',
		'Ñ' => 'n',
		'á' => 'a',
		'í' => 'i',
		'ó' => 'o',
		'ú' => 'u',
		'Á' => 'a',
		'Í' => 'i',
		'Ó' => 'o',
		'Ú' => 'u',
		'ã' => 'a',
		'õ' => 'o',
		'ø' => 'o',
		'å' => 'a',
		'æ' => 'ae',
		'œ' => 'oe',
	];

	/** @param array<string,mixed> $raw @return array<string,mixed> */
	public static function normalize( array $raw ): array {
		$out          = self::DEFAULTS;
		$out['roles'] = self::list( $raw['roles'] ?? [] );
		$sub          = is_array( $raw['sub'] ?? null ) ? $raw['sub'] : [];
		$subRoles     = is_array( $sub['roles'] ?? null ) ? array_map( 'strval', $sub['roles'] ) : [];
		$out['sub']   = [
			'enabled'  => ! empty( $sub['enabled'] ),
			'label'    => trim( (string) ( $sub['label'] ?? '' ) ),
			'options'  => self::list( $sub['options'] ?? [] ),
			'roles'    => array_values( array_intersect( $subRoles, self::slugs( $out['roles'] ) ) ),
			'required' => ! empty( $sub['required'] ),
		];
		return $out;
	}

	/**
	 * "One label per line" → items. Keeps the slug of an $existing item whose label is unchanged.
	 *
	 * @param array<int,array{slug:string,label:string}> $existing
	 * @return array<int,array{slug:string,label:string}>
	 */
	public static function parseList( string $lines, array $existing = [] ): array {
		$byLabel = [];
		foreach ( $existing as $e ) {
			if ( isset( $e['slug'], $e['label'] ) ) {
				$byLabel[ mb_strtolower( trim( (string) $e['label'] ) ) ] = (string) $e['slug'];
			}
		}
		$out  = [];
		$used = [];
		foreach ( preg_split( '/\r\n|\r|\n/', $lines ) ?: [] as $line ) {
			$label = trim( $line );
			if ( $label === '' ) {
				continue;
			}
			$slug  = $byLabel[ mb_strtolower( $label ) ] ?? self::slugify( $label );
			$slug  = self::unique( $slug, $used );
			$out[] = [
				'slug'  => $slug,
				'label' => $label,
			];
		}
		return $out;
	}

	public static function slugify( string $label ): string {
		$s = strtr( trim( $label ), self::TRANSLIT );
		$s = mb_strtolower( $s );
		$s = preg_replace( '/[^a-z0-9]+/', '-', $s ) ?? '';
		$s = trim( $s, '-' );
		return $s !== '' ? $s : 'item';
	}

	/** @param array<int,array{slug:string,label:string}> $items @return array<string,string> slug => label */
	public static function labels( array $items ): array {
		$out = [];
		foreach ( $items as $it ) {
			$out[ $it['slug'] ] = $it['label'];
		}
		return $out;
	}

	/** @param array<int,array{slug:string,label:string}> $items @return array<int,string> */
	public static function slugs( array $items ): array {
		return array_values(
			array_map(
				static function ( $it ) {
					return $it['slug'];
				},
				$items
			)
		);
	}

	/**
	 * Drops malformed entries, derives a slug from the label when missing, de-duplicates slugs.
	 * Also used by extensions that keep their own lists in the same settings array.
	 *
	 * @param mixed $raw @return array<int,array{slug:string,label:string}>
	 */
	public static function list( $raw ): array {
		if ( ! is_array( $raw ) ) {
			return [];
		}
		$out  = [];
		$used = [];
		foreach ( $raw as $it ) {
			if ( ! is_array( $it ) || trim( (string) ( $it['label'] ?? '' ) ) === '' ) {
				continue;
			}
			$label = trim( (string) $it['label'] );
			$slug  = trim( (string) ( $it['slug'] ?? '' ) );
			$slug  = self::slugify( $slug !== '' ? $slug : $label );
			$out[] = [
				'slug'  => self::unique( $slug, $used ),
				'label' => $label,
			];
		}
		return $out;
	}

	/** @param array<string,bool> $used (by reference) */
	private static function unique( string $slug, array &$used ): string {
		$base = $slug;
		$i    = 2;
		while ( isset( $used[ $slug ] ) ) {
			$slug = $base . '-' . ( $i++ );
		}
		$used[ $slug ] = true;
		return $slug;
	}
}