<?php

namespace App\Http\Controllers\Video;

use App\Http\Controllers\Controller;
use App\Jobs\VideoGenerationJob;
use App\Models\VideoGeneration;
use App\Services\Video\GeminiScriptService;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Http\Response;
use Illuminate\View\View;
use Symfony\Component\HttpFoundation\BinaryFileResponse;

class Veo3Controller extends Controller
{
    public function __construct(
        private readonly GeminiScriptService $geminiService
    ) {}

    /**
     * 메인 페이지
     */
    public function index(Request $request): View|Response
    {
        if ($request->header('HX-Request')) {
            return response('', 200)->header('HX-Redirect', route('video.veo3.index'));
        }

        return view('video.veo3.index');
    }

    /**
     * 키워드 → 제목 후보 생성
     */
    public function generateTitles(Request $request): JsonResponse
    {
        $request->validate([
            'keyword' => 'required|string|max:100',
        ]);

        $keyword = $request->input('keyword');
        $titles = $this->geminiService->generateTrendingTitles($keyword);

        if (empty($titles)) {
            return response()->json([
                'success' => false,
                'message' => '제목 생성에 실패했습니다. API 키를 확인해주세요.',
            ], 500);
        }

        // DB에 pending 레코드 생성
        $video = VideoGeneration::create([
            'tenant_id' => session('selected_tenant_id'),
            'user_id' => auth()->id(),
            'keyword' => $keyword,
            'status' => VideoGeneration::STATUS_TITLES_GENERATED,
        ]);

        return response()->json([
            'success' => true,
            'video_id' => $video->id,
            'titles' => $titles,
        ]);
    }

    /**
     * 시나리오 생성 (제목 선택 후)
     */
    public function generateScenario(Request $request): JsonResponse
    {
        $request->validate([
            'video_id' => 'required|integer',
            'title' => 'required|string|max:500',
        ]);

        $video = VideoGeneration::findOrFail($request->input('video_id'));
        $title = $request->input('title');

        $scenario = $this->geminiService->generateScenario($title, $video->keyword);

        if (empty($scenario) || empty($scenario['scenes'])) {
            return response()->json([
                'success' => false,
                'message' => '시나리오 생성에 실패했습니다.',
            ], 500);
        }

        $video->update([
            'title' => $title,
            'scenario' => $scenario,
            'status' => VideoGeneration::STATUS_SCENARIO_READY,
        ]);

        return response()->json([
            'success' => true,
            'video_id' => $video->id,
            'scenario' => $scenario,
        ]);
    }

    /**
     * 영상 생성 시작 (Job 디스패치)
     */
    public function generate(Request $request): JsonResponse
    {
        $request->validate([
            'video_id' => 'required|integer',
            'scenario' => 'nullable|array',
        ]);

        $video = VideoGeneration::findOrFail($request->input('video_id'));

        // 이미 생성 중이면 거부
        if (in_array($video->status, [
            VideoGeneration::STATUS_GENERATING_TTS,
            VideoGeneration::STATUS_GENERATING_CLIPS,
            VideoGeneration::STATUS_GENERATING_BGM,
            VideoGeneration::STATUS_ASSEMBLING,
        ])) {
            return response()->json([
                'success' => false,
                'message' => '이미 영상을 생성 중입니다.',
            ], 409);
        }

        $customScenario = $request->input('scenario');

        if ($customScenario) {
            $video->update(['scenario' => $customScenario]);
        }

        $video->updateProgress(VideoGeneration::STATUS_PENDING, 0, '대기 중...');

        VideoGenerationJob::dispatch($video->id, $video->title, $customScenario ?? $video->scenario);

        return response()->json([
            'success' => true,
            'video_id' => $video->id,
            'message' => '영상 생성이 시작되었습니다.',
        ]);
    }

    /**
     * 진행 상태 폴링
     */
    public function status(int $id): JsonResponse
    {
        $video = VideoGeneration::findOrFail($id);

        return response()->json([
            'id' => $video->id,
            'status' => $video->status,
            'progress' => $video->progress,
            'current_step' => $video->current_step,
            'error_message' => $video->error_message,
            'output_path' => $video->output_path ? true : false,
            'cost_usd' => $video->cost_usd,
            'updated_at' => $video->updated_at?->toIso8601String(),
            'created_at' => $video->created_at?->toIso8601String(),
        ]);
    }

    /**
     * 완성 영상 다운로드
     */
    public function download(int $id): BinaryFileResponse|JsonResponse
    {
        $video = VideoGeneration::findOrFail($id);

        if ($video->status !== VideoGeneration::STATUS_COMPLETED || ! $video->output_path) {
            return response()->json(['message' => '아직 영상이 완성되지 않았습니다.'], 404);
        }

        if (! file_exists($video->output_path)) {
            return response()->json(['message' => '영상 파일을 찾을 수 없습니다.'], 404);
        }

        $filename = "shorts_{$video->keyword}_{$video->id}.mp4";
        $filename = preg_replace('/[^a-zA-Z0-9가-힣_\-.]/', '_', $filename);

        return response()->download($video->output_path, $filename, [
            'Content-Type' => 'video/mp4',
        ]);
    }

    /**
     * 영상 미리보기 (스트리밍)
     */
    public function preview(int $id): Response|JsonResponse
    {
        $video = VideoGeneration::findOrFail($id);

        if (! $video->output_path || ! file_exists($video->output_path)) {
            return response()->json(['message' => '영상 파일을 찾을 수 없습니다.'], 404);
        }

        $path = $video->output_path;
        $size = filesize($path);

        return response()->file($path, [
            'Content-Type' => 'video/mp4',
            'Content-Length' => $size,
            'Accept-Ranges' => 'bytes',
        ]);
    }

    /**
     * 생성 이력 목록
     */
    public function history(Request $request): JsonResponse
    {
        $videos = VideoGeneration::where('user_id', auth()->id())
            ->orderByDesc('created_at')
            ->limit(50)
            ->get(['id', 'keyword', 'title', 'status', 'progress', 'cost_usd', 'created_at', 'updated_at']);

        return response()->json([
            'success' => true,
            'data' => $videos,
        ]);
    }

    /**
     * 생성 이력 삭제 (복수)
     */
    public function destroy(Request $request): JsonResponse
    {
        $request->validate([
            'ids' => 'required|array|min:1',
            'ids.*' => 'integer',
        ]);

        $deleted = VideoGeneration::where('user_id', auth()->id())
            ->whereIn('id', $request->input('ids'))
            ->delete();

        return response()->json([
            'success' => true,
            'deleted' => $deleted,
        ]);
    }
}