<?php

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Models\Activity;
use App\Models\Reservation;
use App\Models\TicketGrabEvent;
use App\Models\User;
use App\Models\WechatUser;
use App\Models\WechatUserHomeVisit;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use PhpOffice\PhpSpreadsheet\Spreadsheet;
use PhpOffice\PhpSpreadsheet\Writer\Xlsx;
use Symfony\Component\HttpFoundation\StreamedResponse;

class WechatUserController extends Controller
{
    public function index(Request $request): JsonResponse
    {
        $pageSize = max(1, min(100, (int) $request->input('page_size', 20)));
        $query = $this->buildFilteredQuery($request);
        $paginator = $query->paginate($pageSize);
        $ids = collect($paginator->items())->pluck('id')->map(fn ($id) => (int) $id)->values()->all();
        $paginator->setCollection(collect($this->mapWechatUserRows($paginator->items(), $ids)));

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

    public function export(Request $request): StreamedResponse
    {
        abort_unless($request->user(), 403, '无权限');

        $users = $this->buildFilteredQuery($request)->get();
        $ids = $users->pluck('id')->map(fn ($id) => (int) $id)->values()->all();
        $rows = $this->mapWechatUserRows($users->all(), $ids);

        $table = [[
            '手机号', '昵称', '姓名', '注册时间', '访问量', '预约活动', '预约抢票',
        ]];

        foreach ($rows as $row) {
            $table[] = [
                (string) ($row['phone'] ?? ''),
                (string) ($row['nickname'] ?? ''),
                (string) ($row['real_name'] ?? ''),
                (string) ($row['created_at'] ?? ''),
                (int) ($row['visit_count'] ?? 0),
                $this->formatReservationBriefsForExport($row['activity_reservations'] ?? []),
                $this->formatReservationBriefsForExport($row['ticket_grab_reservations'] ?? []),
            ];
        }

        $spreadsheet = new Spreadsheet;
        $sheet = $spreadsheet->getActiveSheet();
        $sheet->setTitle('用户列表');
        $sheet->fromArray($table, null, 'A1');

        $writer = new Xlsx($spreadsheet);
        $filename = '微信用户列表-'.now()->format('Ymd-His').'.xlsx';

        return response()->streamDownload(function () use ($writer) {
            $writer->save('php://output');
        }, $filename, [
            'Content-Type' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
        ]);
    }

    /**
     * @return Builder<WechatUser>
     */
    private function buildFilteredQuery(Request $request): Builder
    {
        $query = WechatUser::query()->orderByDesc('id');

        if ($request->filled('keyword')) {
            $keyword = trim((string) $request->input('keyword'));
            $query->where(function ($q) use ($keyword) {
                $q->where('phone', 'like', "%{$keyword}%")
                    ->orWhere('nickname', 'like', "%{$keyword}%")
                    ->orWhere('real_name', 'like', "%{$keyword}%");
            });
        }

        if ($request->filled('has_activity_reservation')) {
            $has = filter_var($request->input('has_activity_reservation'), FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
            if ($has === true) {
                $query->whereExists(fn ($sub) => $this->activityReservationExistsSub($sub));
            } elseif ($has === false) {
                $query->whereNotExists(fn ($sub) => $this->activityReservationExistsSub($sub));
            }
        }

        if ($request->filled('has_ticket_grab_reservation')) {
            $has = filter_var($request->input('has_ticket_grab_reservation'), FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
            if ($has === true) {
                $query->whereExists(fn ($sub) => $this->ticketGrabReservationExistsSub($sub));
            } elseif ($has === false) {
                $query->whereNotExists(fn ($sub) => $this->ticketGrabReservationExistsSub($sub));
            }
        }

        $user = $request->user();
        if ($user instanceof User && ! $user->isSuperAdmin()) {
            $venueIds = $user->venues()->pluck('venues.id')->all();
            if (empty($venueIds)) {
                $query->whereRaw('1 = 0');
            } else {
                $query->where(function ($outer) use ($venueIds) {
                    $outer->whereExists(function ($sub) use ($venueIds) {
                        $sub->selectRaw('1')
                            ->from('reservations')
                            ->whereNull('reservations.deleted_at')
                            ->whereColumn('reservations.wechat_user_id', 'wechat_users.id')
                            ->whereIn('reservations.venue_id', $venueIds);
                    })->orWhereExists(function ($sub) use ($venueIds) {
                        $sub->selectRaw('1')
                            ->from('reservations')
                            ->whereNull('reservations.deleted_at')
                            ->whereIn('reservations.venue_id', $venueIds)
                            ->whereNotNull('reservations.visitor_phone')
                            ->whereNotNull('wechat_users.phone')
                            ->whereColumn('reservations.visitor_phone', 'wechat_users.phone');
                    });
                });
            }
        }

        return $query;
    }

    /**
     * @param  array<int, WechatUser>  $users
     * @param  list<int>  $ids
     * @return list<array<string, mixed>>
     */
    private function mapWechatUserRows(array $users, array $ids): array
    {
        if ($ids === []) {
            return [];
        }

        $visitCounts = WechatUserHomeVisit::query()
            ->whereIn('wechat_user_id', $ids)
            ->groupBy('wechat_user_id')
            ->selectRaw('wechat_user_id, COUNT(*) as c')
            ->pluck('c', 'wechat_user_id');

        $activityResMap = $this->loadReservationBriefs($ids, Reservation::KIND_ACTIVITY);
        $ticketGrabResMap = $this->loadReservationBriefs($ids, Reservation::KIND_TICKET_GRAB);

        return array_map(function (WechatUser $wu) use ($visitCounts, $activityResMap, $ticketGrabResMap) {
            $row = $wu->toArray();
            $row['visit_count'] = (int) ($visitCounts[$wu->id] ?? 0);
            $row['activity_reservations'] = $activityResMap[$wu->id] ?? [];
            $row['ticket_grab_reservations'] = $ticketGrabResMap[$wu->id] ?? [];
            if ($row['created_at'] !== null) {
                $row['created_at'] = $wu->created_at?->timezone((string) config('app.timezone'))->format('Y-m-d H:i:s');
            }

            return $row;
        }, $users);
    }

    /**
     * @param  list<int>  $wechatUserIds
     * @return array<int, list<array{title: string, status: string, status_label: string}>>
     */
    private function loadReservationBriefs(array $wechatUserIds, string $kind): array
    {
        if ($wechatUserIds === []) {
            return [];
        }

        $query = Reservation::query()
            ->whereIn('wechat_user_id', $wechatUserIds)
            ->whereNull('deleted_at')
            ->where('status', '!=', 'cancelled');

        if ($kind === Reservation::KIND_TICKET_GRAB) {
            $query->where('reservation_kind', Reservation::KIND_TICKET_GRAB);
        } else {
            $query->where(function ($q) {
                $q->whereNull('reservation_kind')
                    ->orWhere('reservation_kind', Reservation::KIND_ACTIVITY);
            });
        }

        $rows = $query
            ->orderByDesc('id')
            ->get(['id', 'wechat_user_id', 'activity_id', 'ticket_grab_event_id', 'status']);

        $activityIds = $rows->pluck('activity_id')->filter()->unique()->values()->all();
        $eventIds = $rows->pluck('ticket_grab_event_id')->filter()->unique()->values()->all();

        $activityTitles = $activityIds === []
            ? collect()
            : Activity::query()->whereIn('id', $activityIds)->pluck('title', 'id');
        $eventTitles = $eventIds === []
            ? collect()
            : TicketGrabEvent::query()->whereIn('id', $eventIds)->pluck('title', 'id');

        $out = [];
        foreach ($rows as $r) {
            $uid = (int) $r->wechat_user_id;
            $title = $kind === Reservation::KIND_TICKET_GRAB
                ? (string) ($eventTitles[(int) $r->ticket_grab_event_id] ?? ('抢票#'.$r->ticket_grab_event_id))
                : (string) ($activityTitles[(int) $r->activity_id] ?? ('活动#'.$r->activity_id));
            $out[$uid][] = [
                'title' => $title,
                'status' => (string) $r->status,
                'status_label' => $this->reservationStatusLabel((string) $r->status),
            ];
        }

        return $out;
    }

    private function reservationStatusLabel(string $status): string
    {
        return match ($status) {
            'pending' => '待核销',
            'verified' => '已核销',
            'cancelled' => '已取消',
            'expired' => '已过期',
            default => $status,
        };
    }

    /**
     * @param  list<array{title?: string, status_label?: string}>  $items
     */
    private function formatReservationBriefsForExport(array $items): string
    {
        if ($items === []) {
            return '';
        }
        $parts = [];
        foreach ($items as $it) {
            $title = trim((string) ($it['title'] ?? ''));
            $label = trim((string) ($it['status_label'] ?? ''));
            $parts[] = $title !== '' ? "{$title}（{$label}）" : $label;
        }

        return implode('；', $parts);
    }

    private function activityReservationExistsSub($sub): void
    {
        $sub->selectRaw('1')
            ->from('reservations')
            ->whereNull('reservations.deleted_at')
            ->whereColumn('reservations.wechat_user_id', 'wechat_users.id')
            ->where(function ($q) {
                $q->whereNull('reservations.reservation_kind')
                    ->orWhere('reservations.reservation_kind', Reservation::KIND_ACTIVITY);
            });
    }

    private function ticketGrabReservationExistsSub($sub): void
    {
        $sub->selectRaw('1')
            ->from('reservations')
            ->whereNull('reservations.deleted_at')
            ->whereColumn('reservations.wechat_user_id', 'wechat_users.id')
            ->where('reservations.reservation_kind', Reservation::KIND_TICKET_GRAB);
    }
}