<?php

namespace App\Services;

use App\Models\Reservation;
use App\Models\TicketGrabEvent;
use App\Models\TicketGrabEventVenue;
use App\Models\TicketGrabVenueReleaseDay;
use App\Models\Venue;
use Carbon\Carbon;
use DateTimeImmutable;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;

class DashboardTicketGrabStatsService
{
    /**
     * @param  \Illuminate\Support\Collection<int, int|string>  $scopedVenueIds  已按权限收窄的场馆 id
     */
    public function build(int $eventId, string $dateYmd, Collection $scopedVenueIds): array
    {
        $event = TicketGrabEvent::query()->find($eventId);
        if (! $event) {
            return ['error' => '抢票活动不存在'];
        }

        $releaseRows = TicketGrabVenueReleaseDay::query()
            ->where('ticket_grab_event_id', $eventId)
            ->whereDate('release_date', $dateYmd)
            ->whereIn('venue_id', $scopedVenueIds)
            ->with('venue:id,name')
            ->get();

        if ($releaseRows->isEmpty()) {
            return [
                'event' => ['id' => $event->id, 'title' => $event->title, 'booking_audience' => $event->booking_audience],
                'date' => $dateYmd,
                'overview' => [
                    'total_released' => 0,
                    'total_grabbed' => 0,
                    'total_remaining' => 0,
                    'sellout_duration_label' => '-',
                    'remaining_badge' => '尚余0张',
                ],
                'highlights' => [
                    'fastest_sellout' => null,
                    'max_release_venue' => null,
                    'summary' => '当日暂无放票计划或无权限范围内的场馆数据。',
                ],
                'ticket_types' => [],
                'age_groups' => [],
                'venues' => [],
                'hourly_matrix' => ['hours' => [], 'rows' => []],
            ];
        }

        $releaseDayIdList = $releaseRows->pluck('id')->all();

        $totalReleased = 0;
        $totalGrabbed = 0;
        $totalRemaining = 0;
        $venueStats = [];

        foreach ($releaseRows as $row) {
            $pool = (int) $row->carry_in + (int) $row->day_quota;
            $booked = (int) $row->booked_count;
            $remaining = max(0, $pool - $booked);
            $totalReleased += $pool;
            $totalGrabbed += $booked;
            $totalRemaining += $remaining;

            $venueName = $row->venue?->name ?? (Venue::query()->whereKey($row->venue_id)->value('name') ?? '场馆 #'.$row->venue_id);

            $firstAt = Reservation::query()
                ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
                ->where('ticket_grab_event_id', $eventId)
                ->where('ticket_grab_venue_release_day_id', $row->id)
                ->where('status', '!=', 'cancelled')
                ->min('created_at');
            $lastAt = Reservation::query()
                ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
                ->where('ticket_grab_event_id', $eventId)
                ->where('ticket_grab_venue_release_day_id', $row->id)
                ->where('status', '!=', 'cancelled')
                ->max('created_at');
            $soldOut = $pool > 0 && $remaining === 0;
            $durationLabel = '未抢完';
            $seconds = null;
            if ($soldOut && $firstAt && $lastAt) {
                $a = Carbon::parse($firstAt);
                $b = Carbon::parse($lastAt);
                $seconds = max(0, $b->diffInSeconds($a));
                $durationLabel = $this->formatDurationCn($seconds);
            } elseif (! $soldOut) {
                $durationLabel = '未抢完';
            }

            $venueStats[] = [
                'venue_id' => (int) $row->venue_id,
                'venue_name' => $venueName,
                'released' => $pool,
                'grabbed' => $booked,
                'remaining' => $remaining,
                'duration_label' => $durationLabel,
                'duration_seconds' => $seconds,
                'status' => $soldOut ? '抢完' : '未抢完',
                'release_day_id' => (int) $row->id,
            ];
        }

        $overallSelloutLabel = $totalRemaining > 0 ? '未抢完' : $this->overallSelloutDurationLabel($eventId, $releaseDayIdList);

        $fastest = collect($venueStats)
            ->filter(fn ($v) => ($v['duration_seconds'] ?? null) !== null)
            ->sortBy('duration_seconds')
            ->first();

        $maxVenue = collect($venueStats)->sortByDesc('released')->first();

        $highlights = [
            'fastest_sellout' => $fastest
                ? ['venue_name' => $fastest['venue_name'], 'duration_label' => $fastest['duration_label']]
                : null,
            'max_release_venue' => $maxVenue && $maxVenue['released'] > 0
                ? ['venue_name' => $maxVenue['venue_name'], 'released' => $maxVenue['released']]
                : null,
            'summary' => $this->buildSummaryText($totalRemaining, $totalReleased, $totalGrabbed),
        ];

        $ticketTypes = $this->ticketTypeBreakdown($event, $releaseDayIdList);
        $ageGroups = $event->booking_audience === TicketGrabEvent::AUDIENCE_SCHOOL_AGE
            ? $this->ageGroupBreakdown($releaseDayIdList, $dateYmd)
            : [];

        $hourlyMatrix = $this->hourlyMatrix($eventId, $releaseRows, $scopedVenueIds, $dateYmd);

        return [
            'event' => [
                'id' => $event->id,
                'title' => $event->title,
                'booking_audience' => $event->booking_audience,
            ],
            'date' => $dateYmd,
            'overview' => [
                'total_released' => $totalReleased,
                'total_grabbed' => $totalGrabbed,
                'total_remaining' => $totalRemaining,
                'sellout_duration_label' => $overallSelloutLabel,
                'remaining_badge' => '尚余'.$totalRemaining.'张',
            ],
            'highlights' => $highlights,
            'ticket_types' => $ticketTypes,
            'age_groups' => $ageGroups,
            'venues' => array_map(function ($v) {
                return [
                    'venue_id' => $v['venue_id'],
                    'venue_name' => $v['venue_name'],
                    'released' => $v['released'],
                    'grabbed' => $v['grabbed'],
                    'remaining' => $v['remaining'],
                    'duration_label' => $v['duration_label'],
                    'status' => $v['status'],
                ];
            }, $venueStats),
            'hourly_matrix' => $hourlyMatrix,
        ];
    }

    private function overallSelloutDurationLabel(int $eventId, array $releaseDayIds): string
    {
        if ($releaseDayIds === []) {
            return '-';
        }
        $first = Reservation::query()
            ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
            ->where('ticket_grab_event_id', $eventId)
            ->whereIn('ticket_grab_venue_release_day_id', $releaseDayIds)
            ->where('status', '!=', 'cancelled')
            ->min('created_at');
        $last = Reservation::query()
            ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
            ->where('ticket_grab_event_id', $eventId)
            ->whereIn('ticket_grab_venue_release_day_id', $releaseDayIds)
            ->where('status', '!=', 'cancelled')
            ->max('created_at');
        if (! $first || ! $last) {
            return '-';
        }
        $a = Carbon::parse($first);
        $b = Carbon::parse($last);

        return $this->formatDurationCn(max(0, $b->diffInSeconds($a)));
    }

    private function formatDurationCn(int $seconds): string
    {
        if ($seconds <= 0) {
            return '不足1分钟';
        }
        $h = intdiv($seconds, 3600);
        $m = intdiv($seconds % 3600, 60);
        if ($h > 0) {
            return $h.'小时'.($m > 0 ? $m.'分钟' : '');
        }
        if ($m > 0) {
            return $m.'分钟';
        }

        return '不足1分钟';
    }

    private function buildSummaryText(int $remaining, int $released, int $grabbed): string
    {
        if ($released <= 0) {
            return '当日无放票。';
        }
        if ($remaining > 0) {
            return '整体结果：尚余 '.$remaining.' 张，未全部抢完（已抢 '.$grabbed.' / '.$released.'）。';
        }

        return '整体结果：当日票已全部抢完（'.$grabbed.' / '.$released.'）。';
    }

    private function ticketTypeBreakdown(TicketGrabEvent $event, array $releaseDayIds): array
    {
        if ($releaseDayIds === []) {
            return [];
        }
        $rows = Reservation::query()
            ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
            ->where('ticket_grab_event_id', $event->id)
            ->whereIn('ticket_grab_venue_release_day_id', $releaseDayIds)
            ->where('status', '!=', 'cancelled')
            ->selectRaw('ticket_mode, SUM(ticket_count) as people')
            ->groupBy('ticket_mode')
            ->get();

        $out = [];
        foreach ($rows as $r) {
            $mode = $r->ticket_mode;
            $people = (int) $r->people;
            if ($people <= 0) {
                continue;
            }
            if ($mode === 'pair') {
                $label = '1大1小';
            } elseif ($mode === 'single') {
                $label = $event->booking_audience === TicketGrabEvent::AUDIENCE_SCHOOL_AGE ? '1张学生票' : '单人预约';
            } else {
                $label = '其他';
            }
            $out[] = ['label' => $label, 'people_count' => $people];
        }

        return $out;
    }

    private function ageGroupBreakdown(array $releaseDayIds, string $refDateYmd): array
    {
        if ($releaseDayIds === []) {
            return [];
        }
        $reservations = Reservation::query()
            ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
            ->whereIn('ticket_grab_venue_release_day_id', $releaseDayIds)
            ->where('status', '!=', 'cancelled')
            ->whereNotNull('id_card')
            ->get(['id_card', 'ticket_count']);

        $buckets = [
            '1-3年级' => 0,
            '4-6年级' => 0,
            '7-9年级' => 0,
            '其他年龄段' => 0,
        ];
        foreach ($reservations as $res) {
            $raw = (string) $res->id_card;
            $n = max(1, (int) $res->ticket_count);
            $age = $this->ageAtDateFromIdCard($raw, $refDateYmd);
            if ($age === null) {
                $buckets['其他年龄段'] += $n;

                continue;
            }
            if ($age >= 6 && $age <= 8) {
                $buckets['1-3年级'] += $n;
            } elseif ($age >= 9 && $age <= 11) {
                $buckets['4-6年级'] += $n;
            } elseif ($age >= 12 && $age <= 14) {
                $buckets['7-9年级'] += $n;
            } else {
                $buckets['其他年龄段'] += $n;
            }
        }

        return collect($buckets)
            ->map(fn ($n, $label) => ['label' => $label, 'people_count' => (int) $n])
            ->values()
            ->filter(fn ($x) => $x['people_count'] > 0)
            ->values()
            ->all();
    }

    private function ageAtDateFromIdCard(string $id, string $dateYmd): ?int
    {
        $id = strtoupper(trim($id));
        if (strlen($id) !== 18 || ! preg_match('/^\d{17}[\dX]$/', $id)) {
            return null;
        }
        $y = (int) substr($id, 6, 4);
        $m = (int) substr($id, 10, 2);
        $d = (int) substr($id, 12, 2);
        if ($y < 1900 || $m < 1 || $m > 12 || $d < 1 || $d > 31) {
            return null;
        }
        try {
            $birth = new DateTimeImmutable(sprintf('%04d-%02d-%02d', $y, $m, $d));
            $ref = new DateTimeImmutable($dateYmd);
        } catch (\Throwable) {
            return null;
        }

        return $birth->diff($ref)->y;
    }

    /**
     * 行：场馆；列：有抢票的小时；单元格：该小时抢票张数 / 该馆当日已抢（占比）
     */
    private function hourlyMatrix(int $eventId, Collection $releaseRows, Collection $scopedVenueIds, string $dateYmd): array
    {
        $dayIds = $releaseRows->pluck('id')->all();
        if ($dayIds === []) {
            return ['hours' => [], 'rows' => []];
        }

        $hourExpr = DB::connection()->getDriverName() === 'sqlite'
            ? "CAST(strftime('%H', created_at) AS INTEGER)"
            : 'HOUR(created_at)';

        $raw = Reservation::query()
            ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
            ->where('ticket_grab_event_id', $eventId)
            ->whereIn('ticket_grab_venue_release_day_id', $dayIds)
            ->where('status', '!=', 'cancelled')
            ->whereDate('created_at', $dateYmd)
            ->selectRaw('venue_id, '.$hourExpr.' as h, SUM(ticket_count) as c')
            ->groupBy('venue_id', 'h')
            ->get();

        $hours = $raw->pluck('h')->unique()->sort()->values()->map(fn ($h) => (int) $h)->all();
        if ($hours === []) {
            return ['hours' => [], 'rows' => []];
        }

        $byVenueHour = [];
        foreach ($raw as $r) {
            $vid = (int) $r->venue_id;
            $h = (int) $r->h;
            $byVenueHour[$vid][$h] = (int) $r->c;
        }

        $venueDayTotals = Reservation::query()
            ->where('reservation_kind', Reservation::KIND_TICKET_GRAB)
            ->where('ticket_grab_event_id', $eventId)
            ->whereIn('ticket_grab_venue_release_day_id', $dayIds)
            ->where('status', '!=', 'cancelled')
            ->whereDate('created_at', $dateYmd)
            ->selectRaw('venue_id, SUM(ticket_count) as c')
            ->groupBy('venue_id')
            ->pluck('c', 'venue_id');

        $eventDayTotal = (int) $venueDayTotals->sum();

        $rows = [];
        foreach ($releaseRows->sortBy('venue_id') as $rr) {
            $vid = (int) $rr->venue_id;
            $name = $rr->venue?->name ?? (Venue::query()->whereKey($vid)->value('name') ?? '场馆 #'.$vid);
            $dayTot = (int) ($venueDayTotals[$vid] ?? 0);
            $cells = [];
            foreach ($hours as $h) {
                $g = (int) ($byVenueHour[$vid][$h] ?? 0);
                $pct = $dayTot > 0 ? round(100 * $g / $dayTot, 2) : 0.0;
                $cells[] = [
                    'hour' => $h,
                    'grabbed' => $g,
                    'display' => $dayTot > 0 ? $g.'/'.$dayTot.' ('.$pct.'%)' : (string) $g,
                ];
            }
            $rowPct = $eventDayTotal > 0 ? round(100 * $dayTot / $eventDayTotal, 2) : 0.0;
            $rows[] = [
                'venue_id' => $vid,
                'venue_name' => $name,
                'cells' => $cells,
                'day_total' => $dayTot,
                'day_share_display' => $eventDayTotal > 0 ? $dayTot.'/'.$eventDayTotal.' ('.$rowPct.'%)' : (string) $dayTot,
            ];
        }

        return [
            'hours' => $hours,
            'rows' => $rows,
        ];
    }

    /** @return \Illuminate\Support\Collection<int, int|string> */
    public static function scopedVenueIdsForEvent(int $eventId, Collection $allowedVenueIds): Collection
    {
        $pivot = TicketGrabEventVenue::query()
            ->where('ticket_grab_event_id', $eventId)
            ->pluck('venue_id')
            ->map(fn ($id) => (int) $id)
            ->unique()
            ->values();

        if ($pivot->isEmpty()) {
            return collect();
        }

        $allow = $allowedVenueIds->map(fn ($id) => (int) $id);

        return $pivot->filter(fn ($id) => $allow->contains((int) $id))->values();
    }
}