<?php
declare(strict_types=1);

namespace FlysystemOffload\Media;

use FlysystemOffload\Helpers\PathHelper;
use League\Flysystem\FilesystemOperator;

final class MediaHooks {
    private FilesystemOperator $filesystem;
    private array $config;
    private string $protocol;
    private string $streamHost;
    private string $streamRootPrefix;
    private string $s3Prefix;
    private string $baseUrl;
    private string $effectiveBaseUrl;
    private string $remoteUrlPathPrefix;
    private bool $deleteRemote;
    private bool $preferLocal;

    public function __construct(FilesystemOperator $filesystem, array $config) {
        $this->filesystem = $filesystem;
        $this->config = $config;
        $this->protocol = (string) ($config['stream']['protocol'] ?? 'flysystem');

        $this->streamRootPrefix = PathHelper::normalize((string) ($config['stream']['root_prefix'] ?? ''));
        $this->streamHost = PathHelper::normalize((string) ($config['stream']['host'] ?? ''));
        $this->s3Prefix = PathHelper::normalize((string) ($config['s3']['prefix'] ?? ''));

        $this->baseUrl = $this->normaliseBaseUrl((string) ($config['uploads']['base_url'] ?? content_url('uploads')));
        $this->remoteUrlPathPrefix = $this->buildRemoteUrlPathPrefix();
        $this->effectiveBaseUrl = $this->calculateEffectiveBaseUrl($this->baseUrl, $this->remoteUrlPathPrefix);

        $this->deleteRemote = (bool) ($config['uploads']['delete_remote'] ?? true);
        $this->preferLocal = (bool) ($config['uploads']['prefer_local_for_missing'] ?? false);

        error_log(sprintf(
            '[MediaHooks] Initialized - protocol: %s, host: %s, root_prefix: %s, base_url: %s, effective_base_url: %s',
            $this->protocol,
            $this->streamHost,
            $this->streamRootPrefix,
            $this->baseUrl,
            $this->effectiveBaseUrl
        ));
    }

    public function register(): void {
        add_filter('upload_dir', [$this, 'filterUploadDir'], 20);
        add_filter('pre_option_upload_path', '__return_false');
        add_filter('pre_option_upload_url_path', '__return_false');
        add_filter('wp_get_attachment_url', [$this, 'rewriteAttachmentUrl'], 9, 2);
        add_filter('image_downsize', [$this, 'filterImageDownsize'], 10, 3);
        add_action('delete_attachment', [$this, 'deleteRemoteFiles']);
    }

    public function filterUploadDir(array $uploads): array {
        $subdir = $uploads['subdir'] ?? '';
        $normalizedSubdir = $subdir !== '' ? PathHelper::normalize($subdir) : '';

        $streamSubdir = $normalizedSubdir !== '' ? '/' . $normalizedSubdir : '';
        $streamBase = sprintf('%s://%s', $this->protocol, $this->streamHost ?: 'default');

        $uploads['path'] = $streamBase . $streamSubdir;
        $uploads['basedir'] = $streamBase;
        $uploads['baseurl'] = rtrim($this->effectiveBaseUrl, '/');
        $uploads['url'] = $this->buildPublicUrl($normalizedSubdir);
        $uploads['subdir'] = $normalizedSubdir !== '' ? '/' . $normalizedSubdir : '';
        $uploads['error'] = false;

        $uploads['flysystem_protocol'] = $this->protocol;
        $uploads['flysystem_host'] = $this->streamHost;
        $uploads['flysystem_root_prefix'] = $this->streamRootPrefix;

        error_log(sprintf(
            '[MediaHooks] Upload dir filtered - path: %s, url: %s',
            $uploads['path'],
            $uploads['url']
        ));

        return $uploads;
    }

    public function rewriteAttachmentUrl(string $url, int $attachmentId): string {
        $file = get_post_meta($attachmentId, '_wp_attached_file', true);
        if (! $file) {
            return $url;
        }

        $relativePath = PathHelper::normalize($file);
        if ($relativePath === '') {
            return $url;
        }

        if ($this->remoteUrlPathPrefix !== '') {
            $prefixWithSlash = $this->remoteUrlPathPrefix . '/';
            if (str_starts_with($relativePath, $prefixWithSlash)) {
                $relativePath = substr($relativePath, strlen($prefixWithSlash));
            } elseif ($relativePath === $this->remoteUrlPathPrefix) {
                $relativePath = '';
            }
        }

        $remoteUrl = $this->buildPublicUrl($relativePath);

        if (! $this->preferLocal) {
            return $remoteUrl;
        }

        try {
            if ($this->filesystem->fileExists($this->toRemotePath($relativePath))) {
                return $remoteUrl;
            }
        } catch (\Throwable $exception) {
            error_log(sprintf(
                '[Flysystem Offload] No se pudo verificar la existencia remota de "%s": %s',
                $relativePath,
                $exception->getMessage()
            ));
        }

        return $url;
    }

    public function filterImageDownsize(bool|array $out, int $attachmentId, array|string $size): bool|array {
        return false;
    }

    public function deleteRemoteFiles(int $attachmentId): void {
        if (! $this->deleteRemote) {
            return;
        }

        $files = $this->gatherAttachmentFiles($attachmentId);

        foreach ($files as $file) {
            $key = $this->toRemotePath($file);

            try {
                if ($this->filesystem->fileExists($key)) {
                    $this->filesystem->delete($key);
                }
            } catch (\Throwable $exception) {
                error_log(sprintf(
                    '[Flysystem Offload] No se pudo eliminar el archivo remoto "%s": %s',
                    $key,
                    $exception->getMessage()
                ));
            }
        }
    }

    /**
     * @return list<string>
     */
    private function gatherAttachmentFiles(int $attachmentId): array {
        $files = [];

        $attachedFile = get_post_meta($attachmentId, '_wp_attached_file', true);
        if ($attachedFile) {
            $files[] = $attachedFile;
        }

        $meta = wp_get_attachment_metadata($attachmentId);

        if (is_array($meta)) {
            if (! empty($meta['file'])) {
                $files[] = $meta['file'];
            }

            if (! empty($meta['sizes']) && is_array($meta['sizes'])) {
                $baseDir = $this->dirName($meta['file'] ?? '');
                foreach ($meta['sizes'] as $sizeMeta) {
                    if (! empty($sizeMeta['file'])) {
                        $files[] = ($baseDir !== '' ? $baseDir . '/' : '') . $sizeMeta['file'];
                    }
                }
            }
        }

        $files = array_filter($files, static fn ($file) => is_string($file) && $file !== '');

        return array_values(array_unique($files, SORT_STRING));
    }

    private function dirName(string $path): string {
        $directory = dirname($path);
        return $directory === '.' ? '' : $directory;
    }

    private function toRemotePath(string $file): string {
        $segments = [];

        // ✅ Solo agregar si NO están vacíos
        if ($this->streamRootPrefix !== '') {
            $segments[] = $this->streamRootPrefix;
        }

        if ($this->streamHost !== '') {
            $segments[] = $this->streamHost;
        }

        $segments[] = $file;

        $remotePath = PathHelper::join(...$segments);

        error_log(sprintf(
            '[MediaHooks] toRemotePath - file: %s, remote: %s',
            $file,
            $remotePath
        ));

        return $remotePath;
    }

    private function normaliseBaseUrl(string $baseUrl): string {
        $baseUrl = trim($baseUrl);
        if ($baseUrl === '') {
            $baseUrl = content_url('uploads');
        }

        return rtrim($baseUrl, '/');
    }

    private function buildRemoteUrlPathPrefix(): string {
        $segments = array_filter(
            [$this->s3Prefix, $this->streamRootPrefix, $this->streamHost],
            static fn (string $segment): bool => $segment !== ''
        );

        return PathHelper::join(...$segments);
    }

    private function calculateEffectiveBaseUrl(string $baseUrl, string $pathPrefix): string {
        $baseUrl = rtrim($baseUrl, '/');

        if ($pathPrefix === '') {
            return $baseUrl;
        }

        $basePath = trim((string) parse_url($baseUrl, PHP_URL_PATH), '/');

        if ($basePath !== '' && str_ends_with($basePath, $pathPrefix)) {
            return $baseUrl;
        }

        return $baseUrl;
    }

    private function buildPublicUrl(string $relativePath): string {
        $base = rtrim($this->effectiveBaseUrl, '/');

        if ($relativePath === '') {
            return $base;
        }

        return $base . '/' . PathHelper::normalize($relativePath);
    }
}