<?php

namespace App\Services\Simulation;

use App\Models\LhcOrder;
use Illuminate\Support\Facades\DB;
use Throwable;

/**
 * 自动任务执行器，由 simulation:run 命令周期调用。
 * 每次只推进一个动作并写一条事件；游标保存在运行记录上，暂停、停止、进程重启都能从原处继续，不会重复执行。
 */
final class SimulationRunner
{
    private const WAIT_SECONDS = 10;      // 等待彩票开奖时的重试间隔
    private const MAX_WAITS = 180;        // 最多等 30 分钟
    private const MAX_FAILURE_STREAK = 10; // 连续失败这么多次就把整个运行标为失败

    /** 推进所有到期的运行，返回本次执行的动作数。 */
    public static function tick(): int
    {
        if (!SimulationSettings::enabled()) return 0;
        $settings = SimulationSettings::all();
        $slots = (int) $settings['simulation_max_concurrency'] - DB::table('simulation_task_runs')->where('status', 'running')->count();
        if ($slots > 0) {
            $queued = DB::table('simulation_task_runs')->where('status', 'queued')->orderBy('id')->limit($slots)->pluck('id');
            foreach ($queued as $id) {
                DB::table('simulation_task_runs')->where('id', $id)->where('status', 'queued')
                    ->update(['status' => 'running', 'started_at' => now(), 'next_run_at' => now(), 'updated_at' => now()]);
            }
        }
        $budget = max(1, intdiv((int) $settings['simulation_rate_per_minute'], 30));
        $done = 0;
        $due = DB::table('simulation_task_runs')->where('status', 'running')->where('next_run_at', '<=', now())->orderBy('next_run_at')->pluck('id');
        foreach ($due as $id) {
            for ($i = 0; $i < $budget; $i++) {
                [$acted, $continue] = self::advance((int) $id);
                $done += $acted ? 1 : 0;
                if (!$continue) break;
            }
        }
        return $done;
    }

    /** @return array{0:bool,1:bool} [是否执行了动作, 本轮是否可以继续推进这个运行] */
    private static function advance(int $id): array
    {
        return DB::transaction(function () use ($id) {
            $run = DB::table('simulation_task_runs')->where('id', $id)->lockForUpdate()->first();
            if (!$run || $run->status !== 'running' || (string) $run->next_run_at > now()->toDateTimeString()) return [false, false];
            $steps = json_decode($run->steps, true);
            $members = json_decode($run->member_ids, true) ?: [];
            $cursor = json_decode((string) $run->cursor, true) + ['step' => 0, 'member' => 0, 'seq' => 1, 'waited' => 0, 'streak' => 0];
            if ($cursor['step'] >= count($steps)) {
                DB::table('simulation_task_runs')->where('id', $id)->update(['status' => 'completed', 'finished_at' => now(), 'updated_at' => now()]);
                return [false, false];
            }
            $step = $steps[$cursor['step']];
            $memberId = $step['type'] === 'register' ? '' : (string) ($members[$cursor['member']] ?? '');
            $event = ['run_id' => $id, 'member_id' => $memberId, 'step_index' => $cursor['step'], 'seq' => $cursor['seq'], 'action' => $step['type'],
                'status' => 'ok', 'ref_type' => null, 'ref_id' => null, 'amount' => $step['amount'] ?? null, 'message' => '', 'created_at' => now()];
            try {
                if ($step['type'] !== 'register' && $memberId === '') throw new \RuntimeException('没有可用的模拟会员（注册步骤可能失败）');
                $result = DB::transaction(fn () => self::perform($step, $memberId));
                if ($result === null) { // 彩票尚未开奖，稍后再看
                    if (++$cursor['waited'] <= self::MAX_WAITS) {
                        DB::table('simulation_task_runs')->where('id', $id)->update(['cursor' => json_encode($cursor),
                            'next_run_at' => now()->addSeconds(self::WAIT_SECONDS), 'updated_at' => now()]);
                        return [false, false];
                    }
                    throw new \RuntimeException('等待开奖结算超时');
                }
                $event = array_merge($event, $result);
                if ($step['type'] === 'register') {
                    $members[] = $event['member_id'];
                    $event['seq'] = $cursor['member'] + 1; // 注册没有会员，用序号保证事件唯一
                }
                $cursor['streak'] = 0;
            } catch (Throwable $e) {
                $event['status'] = 'failed';
                $event['message'] = mb_substr($e->getMessage(), 0, 500);
                if ($step['type'] === 'register') $event['seq'] = $cursor['member'] + 1;
                $cursor['streak']++;
            }
            DB::table('simulation_task_events')->insertOrIgnore($event);

            $cursor['waited'] = 0;
            if (++$cursor['seq'] > $step['count']) {
                $cursor['seq'] = 1;
                if (++$cursor['member'] >= (int) $run->member_count) { $cursor['member'] = 0; $cursor['step']++; }
            }
            $update = ['cursor' => json_encode($cursor), 'member_ids' => json_encode($members), 'updated_at' => now(),
                'next_run_at' => now()->addSeconds((int) $step['interval']),
                ($event['status'] === 'ok' ? 'completed' : 'failed') => DB::raw(($event['status'] === 'ok' ? 'completed' : 'failed') . ' + 1')];
            if ($event['status'] === 'failed') $update['last_error'] = $event['message'];
            $finished = $cursor['step'] >= count($steps);
            if ($cursor['streak'] >= self::MAX_FAILURE_STREAK) $update += ['status' => 'failed', 'finished_at' => now()];
            elseif ($finished) $update += ['status' => 'completed', 'finished_at' => now()];
            DB::table('simulation_task_runs')->where('id', $id)->update($update);
            return [true, !isset($update['status']) && (int) $step['interval'] === 0];
        });
    }

    /** 执行一个动作。返回要写进事件的字段；返回 null 表示还要等（彩票未开奖）。 */
    private static function perform(array $step, string $memberId): ?array
    {
        switch ($step['type']) {
            case 'register':
                $created = SimulationMemberService::create(1)[0];
                return ['member_id' => $created['member_id'], 'ref_type' => 'users', 'ref_id' => (string) $created['id'], 'message' => '注册 ' . $created['account']];
            case 'login':
                $login = SimulationMemberService::login($memberId, $step['platform'] ?? 'H5');
                return ['ref_type' => 'user_login', 'ref_id' => (string) $login['id'], 'message' => '登录成功'];
            case 'logout':
                return ['message' => '退出 ' . SimulationMemberService::logout($memberId) . ' 个会话'];
            case 'recharge':
                $order = SimulationFundService::recharge($memberId, $step['amount'], 'third', 'success');
                return ['ref_type' => 'payment_orders', 'ref_id' => (string) $order->id, 'message' => '充值成功'];
            case 'withdraw':
                $order = SimulationFundService::withdrawApply($memberId, $step['amount']);
                SimulationFundService::withdrawAudit((int) $order->id, true);
                return ['ref_type' => 'payment_orders', 'ref_id' => (string) $order->id, 'message' => '提现成功'];
            case 'bet':
                if (($step['category'] ?? 'lottery') === 'sport') {
                    $order = SimulationBetService::sport($memberId, $step['amount'], number_format(mt_rand(150, 250) / 100, 2, '.', ''));
                    return ['ref_type' => 'sport_order', 'ref_id' => (string) $order->id, 'message' => '体育下注 赔率 ' . (float) $order->odd];
                }
                $keywords = ['大', '小', '单', '双'][mt_rand(0, 3)];
                $order = SimulationBetService::lottery($memberId, $keywords, $step['amount']);
                return ['ref_type' => 'lhc_order', 'ref_id' => (string) $order->id, 'message' => "彩票下注 {$order->issue} 期 {$keywords}"];
            case 'settle':
                $pending = LhcOrder::where('member_id', $memberId)->where('bet_source', LhcOrder::SOURCE_SIMULATION)
                    ->where('lottery_status', LhcOrder::STATUS_STAY)->count();
                $user = SimulationSettings::member($memberId);
                $sport = SimulationBetService::sportQuery()->where('sport_order.user_id', (string) $user->user_id)
                    ->where('sport_order.settlement_status', 0)->where('sport_order.status', 1)->pluck('sport_order.id');
                foreach ($sport as $orderId) {
                    $mode = $step['settle_mode'] ?? 'random';
                    SimulationBetService::settleSport((int) $orderId, $mode === 'random' ? ['win', 'lose', 'draw', 'half'][mt_rand(0, 3)] : $mode);
                }
                if ($pending > 0) return null;
                return ['amount' => null, 'message' => '体育结算 ' . count($sport) . ' 单，彩票已全部开奖'];
        }
        throw new \RuntimeException('未知步骤：' . $step['type']);
    }
}