<?php

namespace App\Models;

use App\Support\BizDateTime;
use Carbon\CarbonInterface;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Database\Eloquent\Relations\HasMany;

class AudienceSession extends Model
{
    public const STATUS_OPEN = 'open';

    public const STATUS_NOT_STARTED = 'not_started';

    public const STATUS_EXPIRED = 'expired';

    public const STATUS_FULL = 'full';

    protected $fillable = [
        'competition_id',
        'code',
        'name',
        'name_en',
        'event_date_text',
        'event_date_text_en',
        'address',
        'address_en',
        'capacity',
        'signup_start_at',
        'signup_end_at',
        'is_final',
        'sort',
        'enabled',
    ];

    /**
     * @var array<string, string>
     */
    protected $casts = [
        'capacity' => 'integer',
        'signup_start_at' => 'datetime',
        'signup_end_at' => 'datetime',
        'is_final' => 'boolean',
        'sort' => 'integer',
        'enabled' => 'boolean',
    ];

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

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

    public function registeredCount(): int
    {
        if (array_key_exists('registrations_count', $this->attributes)) {
            return (int) $this->attributes['registrations_count'];
        }

        return (int) $this->registrations()->count();
    }

    public function remainingCount(): int
    {
        return max(0, (int) $this->capacity - $this->registeredCount());
    }

    public function checkedInCount(): int
    {
        if (array_key_exists('checked_in_count', $this->attributes)) {
            return (int) $this->attributes['checked_in_count'];
        }

        return (int) $this->registrations()->whereNotNull('checked_in_at')->count();
    }

    public function windowStatus(?CarbonInterface $now = null): string
    {
        $now = ($now ?? now())->timezone(BizDateTime::TIMEZONE);
        $start = $this->signup_start_at?->copy()->timezone(BizDateTime::TIMEZONE);
        $end = $this->signup_end_at?->copy()->timezone(BizDateTime::TIMEZONE);

        if ($start && $now->lt($start)) {
            return self::STATUS_NOT_STARTED;
        }
        if ($end && $now->gt($end)) {
            return self::STATUS_EXPIRED;
        }
        if ($this->remainingCount() <= 0) {
            return self::STATUS_FULL;
        }

        return self::STATUS_OPEN;
    }

    public function isAvailable(?CarbonInterface $now = null): bool
    {
        return $this->enabled && $this->windowStatus($now) === self::STATUS_OPEN;
    }

    public function statusLabel(?CarbonInterface $now = null): string
    {
        return match ($this->windowStatus($now)) {
            self::STATUS_NOT_STARTED => $this->openFromLabel(),
            self::STATUS_EXPIRED => '已截止',
            self::STATUS_FULL => '已满额',
            default => '报名中',
        };
    }

    public function openFromLabel(): string
    {
        $start = $this->signup_start_at?->copy()->timezone(BizDateTime::TIMEZONE);
        if ($start === null) {
            return '即将开放';
        }

        return $start->format('m.d').' 开放';
    }
}