<?php

namespace App\Services;

use App\Models\AudienceRegistration;
use App\Models\AudienceSession;
use App\Models\Competition;
use App\Models\User;
use App\Support\BizDateTime;
use Illuminate\Support\Facades\DB;
use Illuminate\Validation\ValidationException;

class AudienceRegistrationService
{
    /**
     * @param  array{audience_session_id: int, name: string, company?: string|null, job?: string|null, purpose: string}  $data
     */
    public function register(User $user, Competition $competition, array $data): AudienceRegistration
    {
        return DB::transaction(function () use ($user, $competition, $data) {
            /** @var AudienceSession|null $session */
            $session = AudienceSession::query()
                ->where('competition_id', $competition->id)
                ->whereKey($data['audience_session_id'])
                ->lockForUpdate()
                ->first();

            if ($session === null) {
                throw ValidationException::withMessages([
                    'audience_session_id' => ['场次不存在'],
                ]);
            }

            if (! $session->enabled) {
                throw ValidationException::withMessages([
                    'audience_session_id' => ['该场次暂未开放报名'],
                ]);
            }

            $now = now()->timezone(BizDateTime::TIMEZONE);
            $status = $session->windowStatus($now);
            if ($status === AudienceSession::STATUS_NOT_STARTED) {
                throw ValidationException::withMessages([
                    'audience_session_id' => ['该场次尚未开始报名'],
                ]);
            }
            if ($status === AudienceSession::STATUS_EXPIRED) {
                throw ValidationException::withMessages([
                    'audience_session_id' => ['该场次报名已截止'],
                ]);
            }

            $already = AudienceRegistration::query()
                ->where('audience_session_id', $session->id)
                ->where('user_id', $user->id)
                ->exists();
            if ($already) {
                throw ValidationException::withMessages([
                    'audience_session_id' => ['您已报名该场次'],
                ]);
            }

            $count = AudienceRegistration::query()
                ->where('audience_session_id', $session->id)
                ->count();
            if ($count >= (int) $session->capacity) {
                throw ValidationException::withMessages([
                    'audience_session_id' => ['该场次已满额'],
                ]);
            }

            return AudienceRegistration::query()->create([
                'competition_id' => $competition->id,
                'audience_session_id' => $session->id,
                'user_id' => $user->id,
                'name' => $data['name'],
                'phone' => trim((string) $user->mobile),
                'company' => $this->nullableText($data['company'] ?? null),
                'job' => $this->nullableText($data['job'] ?? null),
                'purpose' => $data['purpose'],
                'registered_at' => now(),
            ]);
        });
    }

    private function nullableText(mixed $value): ?string
    {
        $s = trim((string) ($value ?? ''));

        return $s === '' ? null : $s;
    }
}