<?php

declare(strict_types=1);

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Models\Artwork;
use App\Models\User;
use App\Services\ThumbnailPresenter;
use App\Services\ThumbnailService;
use App\Support\AvatarUrl;
use App\Support\UsernamePolicy;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;

/**
 * ProfileApiController
 * JSON API endpoints for Profile page v2 tabs.
 */
final class ProfileApiController extends Controller
{
    /**
     * GET /api/profile/{username}/artworks
     * Returns cursor-paginated artworks for the profile page tabs.
     * Supports: sort=latest|trending|rising|views|favs, cursor=...
     */
    public function artworks(Request $request, string $username): JsonResponse
    {
        $user = $this->resolveUser($username);
        if (! $user) {
            return response()->json(['error' => 'User not found'], 404);
        }

        $isOwner = Auth::check() && Auth::id() === $user->id;
        $sort    = $request->input('sort', 'latest');

        $query = Artwork::with('user:id,name,username')
            ->where('user_id', $user->id)
            ->whereNull('deleted_at');

        if (! $isOwner) {
            $query->where('is_public', true)->where('is_approved', true)->whereNotNull('published_at');
        }

        $query = match ($sort) {
            'trending' => $query->orderByDesc('ranking_score'),
            'rising'   => $query->orderByDesc('heat_score'),
            'views'    => $query->orderByDesc('view_count'),
            'favs'     => $query->orderByDesc('favourite_count'),
            default    => $query->orderByDesc('published_at'),
        };

        $perPage  = 24;
        $paginator = $query->cursorPaginate($perPage);

        $data = collect($paginator->items())->map(function (Artwork $art) {
            $present = ThumbnailPresenter::present($art, 'md');
            return [
                'id'           => $art->id,
                'name'         => $art->title,
                'thumb'        => $present['url'],
                'thumb_srcset' => $present['srcset'] ?? $present['url'],
                'width'        => $art->width,
                'height'       => $art->height,
                'username'     => $art->user->username ?? null,
                'uname'        => $art->user->username ?? $art->user->name ?? 'Skinbase',
                'published_at' => $art->published_at,
            ];
        })->values();

        return response()->json([
            'data'        => $data,
            'next_cursor' => $paginator->nextCursor()?->encode(),
            'has_more'    => $paginator->hasMorePages(),
        ]);
    }

    /**
     * GET /api/profile/{username}/favourites
     * Returns cursor-paginated favourites for the profile.
     */
    public function favourites(Request $request, string $username): JsonResponse
    {
        if (! Schema::hasTable('user_favorites')) {
            return response()->json(['data' => [], 'next_cursor' => null, 'has_more' => false]);
        }

        $user = $this->resolveUser($username);
        if (! $user) {
            return response()->json(['error' => 'User not found'], 404);
        }

        $perPage = 24;
        $cursor  = $request->input('cursor');

        $favIds = DB::table('user_favorites as uf')
            ->join('artworks as a', 'a.id', '=', 'uf.artwork_id')
            ->where('uf.user_id', $user->id)
            ->whereNull('a.deleted_at')
            ->where('a.is_public', true)
            ->where('a.is_approved', true)
            ->orderByDesc('uf.created_at')
            ->offset($cursor ? (int) base64_decode($cursor) : 0)
            ->limit($perPage + 1)
            ->pluck('a.id');

        $hasMore = $favIds->count() > $perPage;
        $favIds  = $favIds->take($perPage);

        if ($favIds->isEmpty()) {
            return response()->json(['data' => [], 'next_cursor' => null, 'has_more' => false]);
        }

        $indexed = Artwork::with('user:id,name,username')
            ->whereIn('id', $favIds)
            ->get()
            ->keyBy('id');

        $data = $favIds->filter(fn ($id) => $indexed->has($id))->map(function ($id) use ($indexed) {
            $art     = $indexed[$id];
            $present = ThumbnailPresenter::present($art, 'md');
            return [
                'id'           => $art->id,
                'name'         => $art->title,
                'thumb'        => $present['url'],
                'thumb_srcset' => $present['srcset'] ?? $present['url'],
                'width'        => $art->width,
                'height'       => $art->height,
                'username'     => $art->user->username ?? null,
                'uname'        => $art->user->username ?? $art->user->name ?? 'Skinbase',
            ];
        })->values();

        return response()->json([
            'data'        => $data,
            'next_cursor' => null, // Simple offset pagination for now
            'has_more'    => $hasMore,
        ]);
    }

    /**
     * GET /api/profile/{username}/stats
     * Returns profile statistics.
     */
    public function stats(Request $request, string $username): JsonResponse
    {
        $user = $this->resolveUser($username);
        if (! $user) {
            return response()->json(['error' => 'User not found'], 404);
        }

        $stats = null;
        if (Schema::hasTable('user_statistics')) {
            $stats = DB::table('user_statistics')->where('user_id', $user->id)->first();
        }

        $followerCount = 0;
        if (Schema::hasTable('user_followers')) {
            $followerCount = DB::table('user_followers')->where('user_id', $user->id)->count();
        }

        return response()->json([
            'stats'          => $stats,
            'follower_count' => $followerCount,
        ]);
    }

    private function resolveUser(string $username): ?User
    {
        $normalized = UsernamePolicy::normalize($username);
        return User::query()->whereRaw('LOWER(username) = ?', [$normalized])->first();
    }
}