<?php

namespace App\Services;

use App\Exceptions\BalanceNotEnoughException;
use App\Models\User;
use Illuminate\Support\Facades\DB;

class BalanceService
{
    /**
     * 变更余额
     *
     * @param \App\Models\User $user
     * @param int $changeBalance
     * @param int $action
     * @param string|null $remarks
     * @param mixed $loggable
     * @return void
     */
    public function changeBalance(User $user, int $changeBalance, int $action, ?string $remarks = null, $loggable = null)
    {
        $balance = $user->balance()->lockForUpdate()->first();

        if (is_null($balance)) {
            throw new BalanceNotEnoughException();
        }

        // 变更前余额
        $beforeBalance = $balance->balance;
        $_changeBalance = abs($changeBalance);

        if ($changeBalance > 0) {
            // 收入
            $user->balance()->update([
                'balance' => DB::raw("balance + {$_changeBalance}"),
                'total_revenue' => DB::raw("total_revenue + {$_changeBalance}"),
            ]);
        } else {
            // 支出

            if ($balance->balance < $_changeBalance) {
                throw new BalanceNotEnoughException();
            }

            $user->balance()->update([
                'balance' => DB::raw("balance - {$_changeBalance}"),
                'total_expenses' => DB::raw("total_expenses + {$_changeBalance}"),
            ]);
        }

        $user->balanceLogs()->create([
            'loggable_id' => $loggable?->id,
            'loggable_type' => $loggable?->getMorphClass(),
            'before_balance' => $beforeBalance,
            'change_balance' => $changeBalance,
            'action' => $action,
            'remarks' => $remarks,
        ]);
    }
}