<?php

namespace App\Http\Controllers\Api\Admin;

use App\Http\Controllers\Controller;
use App\Models\Application;
use App\Models\ApplicationFile;
use App\Models\ApplicationReviewScore;
use App\Models\Competition;
use App\Models\ReviewerScope;
use App\Services\AdminApplicationExportService;
use App\Support\ProjectCode;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Storage;
use Illuminate\Validation\Rule;
use Illuminate\Validation\ValidationException;
use Symfony\Component\HttpFoundation\BinaryFileResponse;
use Symfony\Component\HttpFoundation\StreamedResponse;

class ApplicationController extends Controller
{
    public function __construct(
        private readonly AdminApplicationExportService $exportService,
    ) {}

    public function index(Request $request, Competition $competition): JsonResponse
    {
        $data = $this->validatedListFilters($request);

        $query = $this->exportService->buildFilteredQuery($competition, $data)
            ->with(['user.publicSourceChannel'])
            ->withCount(['files', 'reviewScores']);

        $this->applyListSorting($query, $data);

        $perPage = min((int) ($data['per_page'] ?? 15), 100);
        $paginator = $query->paginate($perPage);

        $stats = $this->reviewStatsForApplicationIds(
            $paginator->getCollection()->pluck('id')->map(fn ($id) => (int) $id)->all()
        );

        $trackTitles = $competition->tracks()->pluck('title', 'track_code');
        $reviewerCountsByTrack = ReviewerScope::query()
            ->select('track_code', DB::raw('COUNT(*) as total'))
            ->where('competition_id', $competition->id)
            ->groupBy('track_code')
            ->pluck('total', 'track_code');

        $paginator->getCollection()->transform(function (Application $app) use ($trackTitles, $stats, $reviewerCountsByTrack) {
            $app->loadMissing('signupChannel');

            return $this->toListRow($app, $trackTitles, $stats[(int) $app->id] ?? null, $reviewerCountsByTrack);
        });

        return response()->json($paginator);
    }

    public function batchReviewResult(Request $request, Competition $competition): JsonResponse
    {
        $data = $request->validate([
            'application_ids' => ['required', 'array', 'min:1'],
            'application_ids.*' => ['integer', 'min:1'],
            'result' => ['required', 'string', Rule::in(['passed', 'rejected'])],
            'note' => ['nullable', 'string', 'max:5000'],
        ]);

        $ids = array_values(array_unique(array_map('intval', $data['application_ids'])));
        $apps = Application::query()
            ->where('competition_id', $competition->id)
            ->whereIn('id', $ids)
            ->get();

        if ($apps->count() !== count($ids)) {
            throw ValidationException::withMessages(['application_ids' => ['存在无效的项目编号']]);
        }

        $reviewerCountsByTrack = ReviewerScope::query()
            ->select('track_code', DB::raw('COUNT(*) as total'))
            ->where('competition_id', $competition->id)
            ->groupBy('track_code')
            ->pluck('total', 'track_code');

        $stats = $this->reviewStatsForApplicationIds($ids);
        foreach ($apps as $app) {
            if (! $this->isReviewFullyCompleted($app, $stats[(int) $app->id] ?? null, $reviewerCountsByTrack)) {
                throw ValidationException::withMessages([
                    'application_ids' => ['仅评审已全部完成的项目可设置通过/未通过状态'],
                ]);
            }
        }

        Application::query()
            ->where('competition_id', $competition->id)
            ->whereIn('id', $ids)
            ->update([
                'review_result' => $data['result'],
                'review_result_note' => $data['note'] ?? null,
                'review_result_at' => now(),
            ]);

        return response()->json(['updated' => count($ids)]);
    }

    public function exportMeta(Request $request, Competition $competition): JsonResponse
    {
        $filters = $this->validatedExportMetaFilters($request);
        $mode = (string) $filters['mode'];
        $this->exportService->assertExportable($competition, $filters, $mode);

        $total = $this->exportService->countFiltered($competition, $filters);
        $partSize = $this->exportService->partSize();
        $partCount = $this->exportService->partCount($competition, $filters, $mode);

        return response()->json([
            'total' => $total,
            'part_size' => $partSize,
            'part_count' => $partCount,
            'mode' => $mode,
            'includes_attachments' => $this->exportService->modeIncludesAttachments($mode),
        ]);
    }

    public function export(Request $request, Competition $competition): BinaryFileResponse
    {
        $filters = $this->validatedExportFilters($request);
        $mode = (string) $filters['mode'];
        $this->exportService->assertExportable($competition, $filters, $mode);

        if ($mode === AdminApplicationExportService::MODE_XLSX) {
            $xlsxPath = $this->exportService->buildXlsxExportPath($competition, $filters);

            return response()->download($xlsxPath, $this->exportService->buildXlsxFilename($competition), [
                'Content-Type' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
                'Cache-Control' => 'private, no-store',
            ])->deleteFileAfterSend(true);
        }

        $part = (int) ($filters['part'] ?? 1);
        $partCount = $this->exportService->partCount($competition, $filters, $mode);
        $zipPath = $this->exportService->buildPartZipPath($competition, $filters, $part, $mode);
        $filename = $this->exportService->buildPartFilename($competition, $part, $partCount);

        return response()->download($zipPath, $filename, [
            'Content-Type' => 'application/zip',
            'Cache-Control' => 'private, no-store',
        ])->deleteFileAfterSend(true);
    }

    public function show(Competition $competition, Application $application): JsonResponse
    {
        if ((int) $application->competition_id !== (int) $competition->id) {
            abort(404);
        }

        $application->loadMissing(['files', 'reviewScores.reviewer', 'user.publicSourceChannel', 'signupChannel']);
        $trackTitles = $competition->tracks()->pluck('title', 'track_code');
        $stats = $this->reviewStatsForApplicationIds([(int) $application->id]);
        $reviewerCountsByTrack = ReviewerScope::query()
            ->select('track_code', DB::raw('COUNT(*) as total'))
            ->where('competition_id', $competition->id)
            ->groupBy('track_code')
            ->pluck('total', 'track_code');

        return response()->json(
            $this->toDetail($application, $competition, $trackTitles, $stats[(int) $application->id] ?? null, $reviewerCountsByTrack)
        );
    }

    public function downloadFile(Competition $competition, Application $application, ApplicationFile $file): StreamedResponse
    {
        if ((int) $application->competition_id !== (int) $competition->id
            || (int) $file->application_id !== (int) $application->id) {
            abort(404);
        }

        return Storage::disk($file->disk)->download(
            $file->path,
            $file->clientDownloadName(),
            ['Cache-Control' => 'private, no-store']
        );
    }

    /**
     * @return array<string, mixed>
     */
    private function validatedExportMetaFilters(Request $request): array
    {
        return $request->validate([
            'mode' => ['required', 'string', Rule::in([
                AdminApplicationExportService::MODE_XLSX,
                AdminApplicationExportService::MODE_SELECTED,
                AdminApplicationExportService::MODE_ALL,
            ])],
            'status' => ['sometimes', 'nullable', 'string', 'max:32'],
            'track' => ['sometimes', 'nullable', 'string', 'max:100'],
            'entry_group' => ['sometimes', 'nullable', 'string', 'max:64'],
            'keyword' => ['sometimes', 'nullable', 'string', 'max:100'],
            'signup_channel_id' => ['sometimes', 'nullable', 'integer', 'min:1'],
            'public_source_channel_id' => ['sometimes', 'nullable', 'integer', 'min:1'],
            'review_result' => ['sometimes', 'nullable', 'string', Rule::in(['passed', 'rejected', 'pending'])],
            'application_ids' => ['sometimes', 'array'],
            'application_ids.*' => ['integer', 'min:1'],
        ]);
    }

    /**
     * @return array<string, mixed>
     */
    private function validatedExportFilters(Request $request): array
    {
        $filters = $request->validate([
            'mode' => ['required', 'string', Rule::in([
                AdminApplicationExportService::MODE_XLSX,
                AdminApplicationExportService::MODE_SELECTED,
                AdminApplicationExportService::MODE_ALL,
            ])],
            'status' => ['sometimes', 'nullable', 'string', 'max:32'],
            'track' => ['sometimes', 'nullable', 'string', 'max:100'],
            'entry_group' => ['sometimes', 'nullable', 'string', 'max:64'],
            'keyword' => ['sometimes', 'nullable', 'string', 'max:100'],
            'signup_channel_id' => ['sometimes', 'nullable', 'integer', 'min:1'],
            'public_source_channel_id' => ['sometimes', 'nullable', 'integer', 'min:1'],
            'review_result' => ['sometimes', 'nullable', 'string', Rule::in(['passed', 'rejected', 'pending'])],
            'application_ids' => ['sometimes', 'array'],
            'application_ids.*' => ['integer', 'min:1'],
            'part' => ['sometimes', 'integer', 'min:1'],
        ]);

        if (($filters['mode'] ?? '') !== AdminApplicationExportService::MODE_XLSX && ! isset($filters['part'])) {
            throw ValidationException::withMessages([
                'part' => ['请指定导出分卷序号'],
            ]);
        }

        return $filters;
    }

    /**
     * @return array<string, mixed>
     */
    private function validatedListFilters(Request $request): array
    {
        return $request->validate([
            'page' => ['sometimes', 'integer', 'min:1'],
            'per_page' => ['sometimes', 'integer', 'min:1', 'max:100'],
            'status' => ['sometimes', 'nullable', 'string', 'max:32'],
            'track' => ['sometimes', 'nullable', 'string', 'max:100'],
            'entry_group' => ['sometimes', 'nullable', 'string', 'max:64'],
            'keyword' => ['sometimes', 'nullable', 'string', 'max:100'],
            'signup_channel_id' => ['sometimes', 'nullable', 'integer', 'min:1'],
            'public_source_channel_id' => ['sometimes', 'nullable', 'integer', 'min:1'],
            'review_result' => ['sometimes', 'nullable', 'string', Rule::in(['passed', 'rejected', 'pending'])],
            'sort_by' => ['sometimes', 'nullable', 'string', Rule::in(['team_avg', 'submitted_at'])],
            'sort_dir' => ['sometimes', 'nullable', 'string', Rule::in(['asc', 'desc'])],
        ]);
    }

    /**
     * @param  \Illuminate\Database\Eloquent\Builder<Application>  $query
     * @param  array<string, mixed>  $data
     */
    private function applyListSorting($query, array $data): void
    {
        $sortBy = trim((string) ($data['sort_by'] ?? ''));
        $sortDir = strtolower(trim((string) ($data['sort_dir'] ?? 'desc'))) === 'asc' ? 'asc' : 'desc';

        if ($sortBy === 'team_avg') {
            $avgSub = ApplicationReviewScore::query()
                ->select('application_id', DB::raw('AVG(line_total) as team_avg'))
                ->groupBy('application_id');
            $query->leftJoinSub($avgSub, 'review_avg_sort', function ($join): void {
                $join->on('applications.id', '=', 'review_avg_sort.application_id');
            })
                ->select('applications.*')
                ->orderByRaw('review_avg_sort.team_avg IS NULL')
                ->orderBy('review_avg_sort.team_avg', $sortDir)
                ->orderByDesc('applications.id');

            return;
        }

        $query->orderByDesc('submitted_at')->orderByDesc('id');
    }

    /**
     * @param  array{submitted_review_count?: int, team_sum?: float|null, team_avg?: float|null}|null  $stats
     * @param  \Illuminate\Support\Collection<string, int>  $reviewerCountsByTrack
     */
    private function isReviewFullyCompleted(Application $app, ?array $stats, $reviewerCountsByTrack): bool
    {
        $required = (int) ($reviewerCountsByTrack[(string) ($app->track ?? '')] ?? 0);
        $completed = (int) ($stats['submitted_review_count'] ?? 0);

        return $required > 0 && $completed >= $required;
    }

    /**
     * @param  list<int>  $ids
     * @return array<int, array{submitted_review_count: int, team_sum: float|null, team_avg: float|null}>
     */
    private function reviewStatsForApplicationIds(array $ids): array
    {
        if (count($ids) === 0) {
            return [];
        }

        return ApplicationReviewScore::query()
            ->select([
                'application_id',
                DB::raw('COUNT(*) as submitted_review_count'),
                DB::raw('SUM(line_total) as team_sum'),
                DB::raw('AVG(line_total) as team_avg'),
            ])
            ->whereIn('application_id', $ids)
            ->groupBy('application_id')
            ->get()
            ->mapWithKeys(fn ($row) => [
                (int) $row->application_id => [
                    'submitted_review_count' => (int) $row->submitted_review_count,
                    'team_sum' => $row->team_sum !== null ? (float) $row->team_sum : null,
                    'team_avg' => $row->team_avg !== null ? (float) $row->team_avg : null,
                ],
            ])
            ->all();
    }

    private function toListRow(Application $app, $trackTitles, ?array $stats, $reviewerCountsByTrack = null): array
    {
        $required = (int) ($reviewerCountsByTrack?->get((string) ($app->track ?? '')) ?? 0);
        $completed = (int) ($stats['submitted_review_count'] ?? 0);
        $fullyCompleted = $required > 0 && $completed >= $required;

        return [
            'id' => $app->id,
            'project_code' => ProjectCode::resolve($app),
            'status' => $app->status,
            'project_name' => $app->project_name ?? '',
            'player_name' => $app->player_name ?? '',
            'school' => $app->school ?? '',
            'degree' => $app->degree ?? '',
            'contact_mobile' => $app->contact_mobile ?? '',
            'submitter_name' => $app->user?->name ?? '',
            'submitter_mobile' => $app->user?->mobile ?? '',
            'entry_group' => $app->entry_group ?? '',
            'track_code' => $app->track ?? '',
            'track_title' => $trackTitles->get($app->track ?? '') ?? ($app->track ?? ''),
            'location_label' => $this->formatLocation($app),
            'signup_channel' => $app->signupChannel ? [
                'id' => $app->signupChannel->id,
                'channel_code' => $app->signupChannel->channel_code,
                'channel_name' => $app->signupChannel->channel_name,
            ] : null,
            'signup_channel_code' => $app->signup_channel_code,
            'recommend' => $app->recommend ?? '',
            'submitted_at' => $app->submitted_at?->toIso8601String(),
            'updated_at' => $app->updated_at?->toIso8601String(),
            'files_count' => (int) ($app->files_count ?? 0),
            'submitted_review_count' => $completed,
            'review_required_count' => $required,
            'review_progress' => $required > 0 ? ($completed.'/'.$required) : '-',
            'review_fully_completed' => $fullyCompleted,
            'team_sum' => $stats['team_sum'] ?? null,
            'team_avg' => $stats['team_avg'] ?? null,
            'review_result' => $app->review_result,
            'review_result_note' => $app->review_result_note,
            'review_result_at' => $app->review_result_at?->toIso8601String(),
            'public_source_channel' => $app->user?->publicSourceChannel ? [
                'id' => $app->user->publicSourceChannel->id,
                'source_code' => $app->user->publicSourceChannel->source_code,
                'source_name' => $app->user->publicSourceChannel->source_name,
            ] : null,
            'public_source_code' => $app->user?->public_source_code,
            'public_source_attributed_at' => $app->user?->public_source_attributed_at?->toIso8601String(),
        ];
    }

    private function formatLocation(Application $app): string
    {
        $country = trim((string) ($app->location_country ?? ''));
        if ($country === '海外' && ($app->oversea_country ?? '') !== '') {
            return '海外 / '.$app->oversea_country;
        }

        return implode(' / ', array_values(array_filter([
            $app->location_country,
            $app->location_province,
            $app->location_city,
        ], fn ($v) => $v !== null && trim((string) $v) !== '')));
    }

    private function toDetail(Application $app, Competition $competition, $trackTitles, ?array $stats, $reviewerCountsByTrack = null): array
    {
        $base = $this->toListRow($app, $trackTitles, $stats, $reviewerCountsByTrack);

        return $base + [
            'competition' => [
                'id' => $competition->id,
                'slug' => $competition->slug,
                'name' => $competition->name,
            ],
            'participant' => [
                'id' => $app->user?->id,
                'mobile' => $app->user?->mobile,
                'name' => $app->user?->name,
                'email' => $app->user?->email,
                'company' => $app->user?->company,
            ],
            'contact_email' => $app->contact_email ?? '',
            'degree' => $app->degree ?? '',
            'company_name' => $app->company_name ?? '',
            'location_country' => $app->location_country ?? '',
            'location_province' => $app->location_province ?? '',
            'location_city' => $app->location_city ?? '',
            'oversea_country' => $app->oversea_country ?? '',
            'intro' => $app->intro ?? '',
            'recommend' => $app->recommend ?? '',
            'promise_signed_at' => $app->promise_signed_at?->toIso8601String(),
            'promise_signed' => $app->promise_signed_at !== null,
            'pledge_content_html' => $competition->pledge_content_html ?? '',
            'promise_signature' => $app->promise_signature,
            'signup_channel_state' => $app->signup_channel_state,
            'files' => $app->files->map(fn (ApplicationFile $file) => [
                'id' => $file->id,
                'kind' => $file->kind,
                'original_name' => $file->original_name,
                'size' => $file->size,
                'mime' => $file->mime,
            ])->values(),
            'review_scores' => $app->reviewScores->map(fn (ApplicationReviewScore $score) => [
                'id' => $score->id,
                'reviewer_id' => $score->reviewer_id,
                'reviewer_name' => $score->reviewer?->name,
                'line_total' => $score->line_total !== null ? (string) $score->line_total : null,
                'payload_json' => is_array($score->payload_json) ? $score->payload_json : [],
                'comment' => $this->extractReviewComment(is_array($score->payload_json) ? $score->payload_json : []),
                'updated_at' => $score->updated_at?->format('Y-m-d H:i:s'),
            ])->values(),
        ];
    }

    /**
     * @param  array<string, mixed>  $payload
     */
    private function extractReviewComment(array $payload): string
    {
        foreach (['comment', 'review_comment', 'remark'] as $key) {
            $v = $payload[$key] ?? null;
            if (is_string($v) && trim($v) !== '') {
                return trim($v);
            }
        }

        return '';
    }
}