<?php

namespace App\Models;

use Carbon\Carbon;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;
use Illuminate\Database\Eloquent\SoftDeletes;

class Activity extends Model
{
    use HasFactory, SoftDeletes;

    public const RESERVATION_TYPE_ONLINE = 'online';

    public const RESERVATION_TYPE_OFFLINE = 'offline';

    public const RESERVATION_TYPE_OTHER = 'other';

    /** 需要报名：平台内在线报名（online）；无需报名：none；亦可存自定义短文案，仅展示、逻辑同非 online */
    public const RESERVATION_TYPE_PHONE = 'phone';

    public const RESERVATION_TYPE_WECHAT_MP = 'wechat_mp';

    public const RESERVATION_TYPE_OFFLINE_VISIT = 'offline_visit';

    /** 无需报名（不需要在平台报名） */
    public const RESERVATION_TYPE_NONE = 'none';

    /** 门票说明：写入 offline_reservation_method，取值 free / paid */
    public const TICKET_FREE = 'free';

    public const TICKET_PAID = 'paid';

    protected $fillable = [
        'venue_id',
        'submitted_by',
        'reservation_type',
        'location',
        'check_in_meeting_point',
        'specific_time',
        'offline_reservation_method',
        'ticket_fee_note',
        'external_url',
        'title',
        'contact_name',
        'summary',
        'category',
        'quota',
        'registered_count',
        'start_at',
        'end_at',
        'address',
        'contact_phone',
        'lat',
        'lng',
        'detail_html',
        'cover_image',
        'gallery_media',
        'behind_scenes_media',
        'tags',
        'reservation_notice',
        'open_time',
        'sort',
        'is_active',
        'is_hot',
        'schedule_status',
        'booking_audience',
        'total_quota',
        'min_people_per_order',
        'max_people_per_order',
        'audit_status',
        'audit_remark',
        'last_approved_snapshot',
        'view_count',
        'external_link_click_count',
    ];

    public const AUDIT_APPROVED = 'approved';

    public const AUDIT_PENDING = 'pending';

    public const AUDIT_REJECTED = 'rejected';

    protected $casts = [
        'start_at' => 'datetime',
        'end_at' => 'datetime',
        'lat' => 'float',
        'lng' => 'float',
        'gallery_media' => 'array',
        'behind_scenes_media' => 'array',
        'tags' => 'array',
        'sort' => 'integer',
        'is_active' => 'boolean',
        'is_hot' => 'boolean',
        'total_quota' => 'integer',
        'min_people_per_order' => 'integer',
        'max_people_per_order' => 'integer',
        'last_approved_snapshot' => 'array',
        'view_count' => 'integer',
        'external_link_click_count' => 'integer',
    ];

    protected static function booted(): void
    {
        static::saving(function (Activity $activity) {
            if (self::computeScheduleStatusFromBounds($activity->start_at, $activity->end_at) === 'ended') {
                $activity->is_hot = false;
            }
        });
    }

    /**
     * 已结束活动不应保留热门标记（与列表/首页规则一致）。用于定时任务批量纠正无人保存的记录。
     */
    public static function clearHotFlagsForEndedActivities(): int
    {
        $tz = (string) config('app.timezone');
        $today = Carbon::now($tz)->toDateString();

        return (int) static::query()
            ->where('is_hot', true)
            ->whereNotNull('end_at')
            ->whereDate('end_at', '<', $today)
            ->update(['is_hot' => false]);
    }

    /** 活动待审期间若用快照会与 activity_days 不一致，故前台仅展示已审核通过的记录。 */
    public function scopeVisibleOnH5(Builder $query): Builder
    {
        return $query->where('is_active', true)->where('audit_status', self::AUDIT_APPROVED);
    }

    public function venue(): BelongsTo
    {
        return $this->belongsTo(Venue::class);
    }

    public function submitter(): BelongsTo
    {
        return $this->belongsTo(User::class, 'submitted_by');
    }

    public function reservations(): HasMany
    {
        return $this->hasMany(Reservation::class);
    }

    public function activityDays(): HasMany
    {
        return $this->hasMany(ActivityDay::class)
            ->orderBy('session_start_at')
            ->orderBy('id');
    }

    /**
     * H5 活动列表/热门：未结束优先（按开始日期升序，空开始日置后）；已结束置底（按结束日期降序）。
     */
    public function scopeOrderForH5Listing(Builder $query): Builder
    {
        $today = now()->startOfDay();

        return $query
            ->orderByRaw('CASE WHEN end_at IS NOT NULL AND end_at < ? THEN 1 ELSE 0 END ASC', [$today])
            ->orderByRaw('CASE WHEN end_at IS NOT NULL AND end_at < ? THEN end_at END DESC', [$today])
            ->orderByRaw('CASE WHEN (end_at IS NULL OR end_at >= ?) AND start_at IS NULL THEN 1 ELSE 0 END ASC', [$today])
            ->orderByRaw('CASE WHEN end_at IS NULL OR end_at >= ? THEN start_at END ASC', [$today])
            ->orderByTicketNoteFreeBeforePaid()
            ->orderByDesc('id');
    }

    /**
     * H5 活动列表：进行中 → 未开始 → 已结束；组内按开始时间、id。
     */
    public function scopeOrderByScheduleStatusPriority(Builder $query): Builder
    {
        $today = Carbon::now((string) config('app.timezone'))->toDateString();

        return $query
            ->orderByRaw(
                'CASE
                    WHEN end_at IS NOT NULL AND DATE(end_at) < ? THEN 2
                    WHEN start_at IS NOT NULL AND DATE(start_at) > ? THEN 1
                    ELSE 0
                END ASC',
                [$today, $today]
            )
            ->orderByRaw('start_at IS NULL ASC')
            ->orderBy('start_at', 'asc')
            ->orderByTicketNoteFreeBeforePaid()
            ->orderByDesc('id');
    }

    /**
     * 热门优先，其次进行中 → 未开始 → 已结束；组内按开始时间、id。
     */
    public function scopeOrderByHotThenScheduleStatusPriority(Builder $query): Builder
    {
        $today = Carbon::now((string) config('app.timezone'))->toDateString();

        return $query
            ->orderByDesc('is_hot')
            ->orderByRaw(
                'CASE
                    WHEN end_at IS NOT NULL AND DATE(end_at) < ? THEN 2
                    WHEN start_at IS NOT NULL AND DATE(start_at) > ? THEN 1
                    ELSE 0
                END ASC',
                [$today, $today]
            )
            ->orderByRaw('start_at IS NULL ASC')
            ->orderBy('start_at', 'asc')
            ->orderByTicketNoteFreeBeforePaid()
            ->orderByDesc('id');
    }

    /**
     * 门票说明：免费等非 paid 在前，收费（paid）在后。
     */
    public function scopeOrderByTicketNoteFreeBeforePaid(Builder $query): Builder
    {
        return $query->orderByRaw(
            'CASE WHEN offline_reservation_method = ? THEN 1 ELSE 0 END ASC',
            [self::TICKET_PAID]
        );
    }

    /**
     * 按活动开始/结束日（应用时区下的日历日）计算「未开始 / 进行中 / 已结束」，与后台列表筛选一致。
     */
    public static function computeScheduleStatusFromBounds(?Carbon $start, ?Carbon $end, ?string $tz = null): string
    {
        $tz = $tz ?? (string) config('app.timezone');
        $today = Carbon::now($tz)->toDateString();
        $startD = $start ? $start->copy()->timezone($tz)->toDateString() : null;
        $endD = $end ? $end->copy()->timezone($tz)->toDateString() : null;

        if (! $startD && ! $endD) {
            return 'ongoing';
        }
        if ($startD && ! $endD) {
            return $today < $startD ? 'not_started' : 'ongoing';
        }
        if (! $startD && $endD) {
            return $today > $endD ? 'ended' : 'ongoing';
        }
        if ($today < $startD) {
            return 'not_started';
        }
        if ($today > $endD) {
            return 'ended';
        }

        return 'ongoing';
    }

    /** 列表筛选：按日期实时计算，不依赖 schedule_status 字段的缓存值。 */
    public function scopeWhereComputedScheduleStatus(Builder $query, string $status): Builder
    {
        $tz = (string) config('app.timezone');
        $today = Carbon::now($tz)->toDateString();

        return match ($status) {
            'not_started' => $query->whereNotNull('start_at')->whereDate('start_at', '>', $today),
            'ended' => $query->whereNotNull('end_at')->whereDate('end_at', '<', $today),
            'ongoing' => $query->where(function (Builder $q) use ($today) {
                $q->where(function (Builder $q2) use ($today) {
                    $q2->whereNull('start_at')->orWhereDate('start_at', '<=', $today);
                })->where(function (Builder $q2) use ($today) {
                    $q2->whereNull('end_at')->orWhereDate('end_at', '>=', $today);
                });
            }),
            default => $query,
        };
    }

    /**
     * 是否所有场次单日名额均已耗尽（各场 day_quota - booked_count 均 <= 0）。
     * 无场次时返回 false，避免与「约满」等同。
     */
    public function areAllActivityDaySlotsExhausted(): bool
    {
        if (! $this->relationLoaded('activityDays')) {
            $this->load('activityDays');
        }
        $days = $this->activityDays;
        if ($days->isEmpty()) {
            return false;
        }

        return ! $days->contains(function (ActivityDay $d) {
            return max(0, (int) $d->day_quota - (int) $d->booked_count) > 0;
        });
    }

    /**
     * 列表用：仍有未约满名额，但所有「有余量」的场次均已过可预约时间（截止后未满）。
     * 「预约未开始」的不算截止。
     */
    public function isBookingClosedWithRemainingCapacity(): bool
    {
        if (! $this->relationLoaded('activityDays')) {
            $this->load('activityDays');
        }
        $days = $this->activityDays;
        if ($days->isEmpty()) {
            return false;
        }
        $now = Carbon::now();
        $hasRemainder = false;
        foreach ($days as $d) {
            $avail = max(0, (int) $d->day_quota - (int) $d->booked_count);
            if ($avail <= 0) {
                continue;
            }
            $hasRemainder = true;
            if (! $this->activityDayBookingPeriodEnded($d, $now)) {
                return false;
            }
        }

        return $hasRemainder;
    }

    private function activityDayBookingPeriodEnded(ActivityDay $d, Carbon $now): bool
    {
        if ($d->isSessionMode()) {
            if ($d->booking_opens_at !== null && $d->booking_opens_at->gt($now)) {
                return false;
            }
            $deadline = $d->booking_deadline_at;
            if (! $deadline) {
                return false;
            }

            return $now->gt($deadline);
        }

        if (! $d->opens_at) {
            return false;
        }
        if ($d->opens_at->gt($now)) {
            return false;
        }
        $closesAt = $d->closes_at ?: $d->opens_at->copy()->endOfDay();

        return $closesAt->lt($now);
    }

    /**
     * 按未取消预约的票数合计，回写 activities.registered_count（展示用「已预约总人数」）。
     */
    public static function refreshRegisteredCountFromReservations(int $activityId): void
    {
        $total = (int) Reservation::query()
            ->where('activity_id', $activityId)
            ->where('status', '!=', 'cancelled')
            ->get()
            ->sum(fn (Reservation $r) => max(1, (int) ($r->ticket_count ?? 1)));

        static::query()->where('id', $activityId)->update(['registered_count' => $total]);
    }
}