<?php
/**
 * Exclude rules for the wp-content file scan: the default list (spec 4.6), user globs and skipped groups.
 *
 * Glob rules (matched with fnmatch and FNM_PATHNAME, so "*" never crosses a "/"):
 * - A leading "/" anchors the glob to the wp-content root ("/cache" is the root cache folder only).
 * - A glob without "/" matches any single path segment, so "node_modules" excludes it at every depth.
 * - Any other glob is matched against the relative path and each of its parent paths.
 * - A trailing "/" restricts the glob to directories.
 * Excluding a folder excludes everything below it.
 *
 * @package Mench_Migrate
 */

defined( 'ABSPATH' ) || exit;

class Mench_Migrate_Excludes {

	/** Groups a user can untick, each mapped to the top-level wp-content entries it covers. */
	public const GROUPS = [ 'uploads', 'plugins', 'themes', 'mu-plugins', 'others' ];

	/** @var string[] Normalised globs: defaults first, then the user's. */
	private array $globs;

	/** @var string[] */
	private array $skip_groups;

	/**
	 * @param string[] $user_globs  Extra path or glob excludes.
	 * @param string[] $skip_groups Subset of self::GROUPS to leave out entirely.
	 */
	public function __construct( array $user_globs = [], array $skip_groups = [] ) {
		$clean = [];
		foreach ( $user_globs as $g ) {
			$g = trim( str_replace( '\\', '/', (string) $g ) );
			if ( '' !== $g && '/' !== $g ) {
				$clean[] = $g;
			}
		}
		$this->globs       = array_merge( self::defaults(), $clean );
		$this->skip_groups = array_values( array_intersect( self::GROUPS, array_map( 'strval', $skip_groups ) ) );
	}

	/** The default exclude list (spec 4.6). Root-anchored entries start with "/". */
	public static function defaults(): array {
		return [
			'/debug.log',
			'/*.log',
			'/cache/',
			'/upgrade/',
			'/wflogs/',
			'/ai1wm-backups/',
			'/updraft/',
			'/backups-dup-*',
			'/duplicator-backups/',
			'/wpvividbackups/',
			'/mench-migrate-*/',
			'node_modules/',
			'.git/',
			'.DS_Store',
		];
	}

	/** Whether the relative path (from wp-content, "/" separated) must be left out of the backup. */
	public function is_excluded( string $relative_path, bool $is_dir ): bool {
		$path = trim( str_replace( '\\', '/', $relative_path ), '/' );
		if ( '' === $path ) {
			return false;
		}
		$segments = explode( '/', $path );

		if ( $this->skip_groups && $this->group_skipped( $segments[0], 1 === count( $segments ) ? $is_dir : true ) ) {
			return true;
		}

		$prefix = '';
		$last   = count( $segments ) - 1;
		foreach ( $segments as $i => $segment ) {
			$prefix .= ( '' === $prefix ? '' : '/' ) . $segment;
			$dir     = $i < $last || $is_dir; // Every parent is a directory.
			foreach ( $this->globs as $glob ) {
				if ( $this->matches( $glob, $segment, $prefix, $dir ) ) {
					return true;
				}
			}
		}
		return false;
	}

	private function group_skipped( string $top, bool $is_dir ): bool {
		$named = [ 'uploads', 'plugins', 'themes', 'mu-plugins' ];
		if ( in_array( $top, $named, true ) ) {
			return $is_dir && in_array( $top, $this->skip_groups, true );
		}
		return in_array( 'others', $this->skip_groups, true );
	}

	private function matches( string $glob, string $segment, string $path, bool $is_dir ): bool {
		if ( '/' === substr( $glob, -1 ) ) {
			if ( ! $is_dir ) {
				return false;
			}
			$glob = rtrim( $glob, '/' );
		}
		if ( '' === $glob || '/' === $glob ) {
			return false; // "/" or "//" trims to nothing: it names no path (and $glob[0] would warn).
		}
		if ( '/' === $glob[0] ) {
			return fnmatch( substr( $glob, 1 ), $path, FNM_PATHNAME );
		}
		if ( false === strpos( $glob, '/' ) ) {
			return fnmatch( $glob, $segment, FNM_PATHNAME );
		}
		return fnmatch( $glob, $path, FNM_PATHNAME );
	}
}