<?php
namespace App\Http\Resources;

use Illuminate\Http\Resources\Json\JsonResource;
use Illuminate\Http\Resources\MissingValue;

class ArtworkResource extends JsonResource
{
    /**
     * Transform the resource into an array.
     */
    public function toArray($request): array
    {
        if ($this instanceof MissingValue || $this->resource instanceof MissingValue) {
            return [];
        }
        $get = function ($key) {
            $r = $this->resource;
            if ($r instanceof MissingValue || $r === null) {
                return null;
            }
            // Eloquent model: prefer getAttribute to avoid magic proxies
            if (method_exists($r, 'getAttribute')) {
                return $r->getAttribute($key);
            }
            if (is_array($r)) {
                return $r[$key] ?? null;
            }
            if (is_object($r)) {
                return $r->{$key} ?? null;
            }
            return null;
        };
        $hash = (string) ($get('hash') ?? '');
        $fileExt = (string) ($get('file_ext') ?? '');
        $filesBase = rtrim((string) config('cdn.files_url', ''), '/');

        $buildOriginalUrl = static function (string $hashValue, string $extValue) use ($filesBase): ?string {
            $normalizedHash = strtolower((string) preg_replace('/[^a-f0-9]/', '', $hashValue));
            $normalizedExt = strtolower((string) preg_replace('/[^a-z0-9]/', '', $extValue));
            if ($normalizedHash === '' || $normalizedExt === '') return null;
            $h1 = substr($normalizedHash, 0, 2);
            $h2 = substr($normalizedHash, 2, 2);
            if ($h1 === '' || $h2 === '' || $filesBase === '') return null;

            return sprintf('%s/originals/%s/%s/%s.%s', $filesBase, $h1, $h2, $normalizedHash, $normalizedExt);
        };

        return [
            'slug' => $get('slug'),
            'title' => $get('title'),
            'description' => $get('description'),
            'width' => $get('width'),
            'height' => $get('height'),

            // File URLs are derived from hash/ext (no DB path dependency)
            'file' => [
                'name' => $get('file_name') ?? null,
                'url' => $this->when(! empty($hash) && ! empty($fileExt), fn() => $buildOriginalUrl($hash, $fileExt)),
                'size' => $get('file_size') ?? null,
                'mime_type' => $get('mime_type') ?? null,
            ],

            'categories' => $this->whenLoaded('categories', function () {
                return $this->categories->map(fn($c) => [
                    'slug' => $c->slug ?? null,
                    'name' => $c->name ?? null,
                ])->values();
            }),

            'published_at' => $this->whenNotNull($get('published_at') ? $this->published_at->toAtomString() : null),

            'urls' => [
                'canonical' => $get('canonical_url') ?? null,
            ],
        ];
    }
}