<?php

declare(strict_types=1);

namespace App\Http\Controllers\Api\V1;

use App\Enums\PageStatus;
use App\Http\Controllers\Controller;
use App\Http\Requests\Api\V1\PageRequest;
use App\Http\Resources\PageResource;
use App\Models\Page;
use App\Support\TranslatablePayload;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Http\Resources\Json\AnonymousResourceCollection;

class PageController extends Controller
{
    protected const WITH = ['category', 'author', 'featuredMedia', 'tags'];

    /**
     * GET /api/v1/pages
     *
     * Filters: status, category_id, is_featured, search, translated_in, trashed
     * Sorting: sort=-published_at (prefix with "-" for descending)
     */
    public function index(Request $request): AnonymousResourceCollection
    {
        $this->authorize('viewAny', Page::class);

        $locale = app()->getLocale();

        $pages = Page::query()
            ->with(self::WITH)
            ->when($request->filled('status'), fn ($q) => $q->where('status', $request->string('status')))
            ->when($request->filled('category_id'), fn ($q) => $q->where('category_id', $request->integer('category_id')))
            ->when($request->has('is_featured'), fn ($q) => $q->where('is_featured', $request->boolean('is_featured')))
            // Search inside the active locale's translation rather than across
            // the whole JSON blob, so a Spanish query cannot match English text.
            ->when($request->filled('search'), fn ($q) => $q->where(
                fn ($sub) => $sub
                    ->where("title->{$locale}", 'like', '%'.$request->string('search').'%')
                    ->orWhere("excerpt->{$locale}", 'like', '%'.$request->string('search').'%')
            ))
            ->when($request->filled('translated_in'), fn ($q) => $q->translatedIn((string) $request->string('translated_in')))
            ->when($request->boolean('trashed'), fn ($q) => $q->onlyTrashed())
            // Callers without the publish permission only ever see live content.
            ->unless($request->user()->can('pages.publish'), fn ($q) => $q->published())
            ->tap(fn ($q) => $this->applySort($q, $request))
            ->paginate(perPage: min($request->integer('per_page', 15), 100))
            ->withQueryString();

        return PageResource::collection($pages);
    }

    public function store(PageRequest $request): JsonResponse
    {
        $this->authorize('create', Page::class);

        $page = new Page;
        $page->fill(TranslatablePayload::merge($page, collect($request->validated())->except('tag_ids')->all(), $page->translatable));
        $page->author_id ??= $request->user()->id;

        // A page created as published with no explicit date goes live now.
        if ($page->status === PageStatus::Published && $page->published_at === null) {
            $page->published_at = now();
        }

        $page->save();
        $this->syncTags($page, $request);

        return PageResource::make($page->load(self::WITH))
            ->response()
            ->setStatusCode(201);
    }

    public function show(Request $request, Page $page): PageResource
    {
        $this->authorize('view', $page);

        return PageResource::make($page->load(self::WITH));
    }

    public function update(PageRequest $request, Page $page): PageResource
    {
        $this->authorize('update', $page);

        $page->fill(TranslatablePayload::merge($page, collect($request->validated())->except('tag_ids')->all(), $page->translatable));

        if ($page->status === PageStatus::Published && $page->published_at === null) {
            $page->published_at = now();
        }

        $page->save();
        $this->syncTags($page, $request);

        return PageResource::make($page->load(self::WITH));
    }

    public function destroy(Page $page): JsonResponse
    {
        $this->authorize('delete', $page);

        $page->delete();

        return response()->json(status: 204);
    }

    public function restore(Page $page): PageResource
    {
        $this->authorize('restore', $page);

        $page->restore();

        return PageResource::make($page->load(self::WITH));
    }

    /**
     * Whitelist of sortable columns. Anything else is ignored rather than
     * passed to the query builder.
     *
     * @param  Builder<Page>  $query
     */
    protected function applySort(Builder $query, Request $request): void
    {
        $sort = (string) $request->string('sort', '-created_at');
        $direction = str_starts_with($sort, '-') ? 'desc' : 'asc';
        $column = ltrim($sort, '-');

        $sortable = ['created_at', 'updated_at', 'published_at', 'position', 'status'];

        // Sorting by a translatable column targets the active locale's key.
        if ($column === 'title') {
            $query->orderBy('title->'.app()->getLocale(), $direction);

            return;
        }

        $query->orderBy(in_array($column, $sortable, true) ? $column : 'created_at', $direction);
    }

    protected function syncTags(Page $page, PageRequest $request): void
    {
        if ($request->has('tag_ids')) {
            $page->tags()->sync($request->validated('tag_ids') ?? []);
        }
    }
}