<?php

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use App\Models\WeeklyBrief;
use App\Services\Brief\WeeklyBriefService;
use App\Support\ApiResponse;
use Carbon\Carbon;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Storage;
use Symfony\Component\HttpFoundation\StreamedResponse;
use Throwable;

class WeeklyBriefController extends Controller
{
    use ApiResponse;

    public function __construct(
        protected WeeklyBriefService $service
    ) {}

    public function index(Request $request): JsonResponse
    {
        $data = $request->validate([
            'page' => ['nullable', 'integer', 'min:1'],
            'page_size' => ['nullable', 'integer', 'min:1', 'max:100'],
        ]);

        $paginator = WeeklyBrief::query()
            ->orderByDesc('week_start')
            ->paginate((int) ($data['page_size'] ?? 20))
            ->withQueryString();

        $paginator->getCollection()->transform(fn (WeeklyBrief $b) => $this->serializeList($b));

        return $this->paginated($paginator);
    }

    public function show(int $weeklyBrief): JsonResponse
    {
        $model = WeeklyBrief::query()->findOrFail($weeklyBrief);

        return $this->ok($this->serializeDetail($model));
    }

    public function generate(Request $request): JsonResponse
    {
        $data = $request->validate([
            'week_start' => ['nullable', 'date'],
            'week_end' => ['nullable', 'date', 'after_or_equal:week_start'],
            'week_offset' => ['nullable', 'integer', 'min:0', 'max:52'],
        ]);

        try {
            if (! empty($data['week_start']) && ! empty($data['week_end'])) {
                $weekStart = Carbon::parse($data['week_start'])->timezone('Asia/Shanghai')->startOfDay();
                $weekEnd = Carbon::parse($data['week_end'])->timezone('Asia/Shanghai')->endOfDay();
            } elseif (isset($data['week_offset'])) {
                [$weekStart, $weekEnd] = $this->service->resolveWeekByOffset((int) $data['week_offset']);
            } else {
                [$weekStart, $weekEnd] = $this->service->resolvePreviousWeek();
            }

            $brief = $this->service->generate(
                $weekStart,
                $weekEnd,
                $request->user()?->id,
                replace: true,
            );
        } catch (Throwable $e) {
            return $this->fail('简报生成失败：'.$e->getMessage(), 500);
        }

        return $this->ok($this->serializeDetail($brief), '简报已生成');
    }

    public function weekOptions(): JsonResponse
    {
        return $this->ok(['items' => $this->service->weekOptions()]);
    }

    public function download(int $weeklyBrief): StreamedResponse|JsonResponse
    {
        $model = WeeklyBrief::query()->findOrFail($weeklyBrief);
        if (! $model->docx_path || ! Storage::disk('local')->exists($model->docx_path)) {
            return $this->fail('Word 简报文件不存在，请重新生成', 404);
        }

        $filename = sprintf(
            '高校科技成果周报_%s_%s.docx',
            $model->week_start?->format('Ymd'),
            $model->week_end?->format('Ymd'),
        );

        return Storage::disk('local')->download($model->docx_path, $filename);
    }

    /**
     * @return array<string, mixed>
     */
    protected function serializeList(WeeklyBrief $brief): array
    {
        return [
            'id' => $brief->id,
            'week_start' => $brief->week_start?->toDateString(),
            'week_end' => $brief->week_end?->toDateString(),
            'title' => $brief->title,
            'stats' => $brief->stats_json,
            'generated_at' => $brief->generated_at?->toIso8601String(),
            'has_docx' => (bool) ($brief->docx_path && Storage::disk('local')->exists($brief->docx_path)),
        ];
    }

    /**
     * @return array<string, mixed>
     */
    protected function serializeDetail(WeeklyBrief $brief): array
    {
        return [
            ...$this->serializeList($brief),
            'docx_path' => $brief->docx_path,
        ];
    }
}