<?php

namespace App\Services;

use App\Models\BalanceTransaction;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Str;
use InvalidArgumentException;

class BalanceService
{
    public function balance(int $accountId): string
    {
        $value = DB::connection('azerothcore_auth')->table('account_balances')
            ->where('account_id', $accountId)
            ->value('balance');

        return $this->fromCents($this->toCents((string) ($value ?? '0')));
    }

    /** @return Collection<int, BalanceTransaction> */
    public function recentTransactions(int $accountId, int $limit = 10): Collection
    {
        return BalanceTransaction::query()
            ->where('account_id', $accountId)
            ->latest('id')
            ->limit($limit)
            ->get();
    }

    public function spend(int $accountId, string $amount, string $reference, ?string $description = null): BalanceTransaction
    {
        $cents = $this->toCents($amount);
        if ($cents <= 0) {
            throw new InvalidArgumentException('Сумма списания должна быть больше нуля.');
        }

        return DB::connection('azerothcore_auth')->transaction(function () use ($accountId, $cents, $reference, $description): BalanceTransaction {
            $existing = BalanceTransaction::query()->where('reference', $reference)->first();
            if ($existing) {
                if ($existing->account_id !== $accountId || $this->toCents((string) $existing->amount) !== -$cents) {
                    throw new InvalidArgumentException('Ключ операции уже использован с другими параметрами.');
                }

                return $existing;
            }

            $balance = DB::connection('azerothcore_auth')->table('account_balances')
                ->where('account_id', $accountId)
                ->lockForUpdate()
                ->first();
            $current = $this->toCents((string) ($balance->balance ?? '0'));

            if ($current < $cents) {
                throw new InvalidArgumentException('Недостаточно средств.');
            }

            $after = $this->fromCents($current - $cents);
            DB::connection('azerothcore_auth')->table('account_balances')
                ->where('account_id', $accountId)
                ->update(['balance' => $after, 'updated_at' => now()]);

            return BalanceTransaction::query()->create([
                'account_id' => $accountId,
                'type' => BalanceTransaction::TYPE_SPEND,
                'amount' => $this->fromCents(-$cents),
                'balance_after' => $after,
                'reference' => $reference,
                'metadata' => array_filter(['description' => $description]),
            ]);
        }, 3);
    }

    public function adjustByAdmin(
        int $accountId,
        string $amount,
        string $direction,
        int $adminAccountId,
        string $adminUsername,
        string $reason,
    ): BalanceTransaction {
        $cents = $this->toCents($amount);
        if ($cents <= 0 || ! in_array($direction, ['credit', 'debit'], true)) {
            throw new InvalidArgumentException('Некорректная корректировка баланса.');
        }

        return DB::connection('azerothcore_auth')->transaction(function () use ($accountId, $cents, $direction, $adminAccountId, $adminUsername, $reason): BalanceTransaction {
            DB::connection('azerothcore_auth')->table('account_balances')->insertOrIgnore([
                'account_id' => $accountId,
                'balance' => '0.00',
                'created_at' => now(),
                'updated_at' => now(),
            ]);
            $balance = DB::connection('azerothcore_auth')->table('account_balances')
                ->where('account_id', $accountId)
                ->lockForUpdate()
                ->firstOrFail();
            $current = $this->toCents((string) $balance->balance);
            $delta = $direction === 'credit' ? $cents : -$cents;

            if ($current + $delta < 0) {
                throw new InvalidArgumentException('Недостаточно средств для ручного списания.');
            }

            $after = $this->fromCents($current + $delta);
            DB::connection('azerothcore_auth')->table('account_balances')
                ->where('account_id', $accountId)
                ->update(['balance' => $after, 'updated_at' => now()]);

            return BalanceTransaction::query()->create([
                'account_id' => $accountId,
                'type' => $direction === 'credit' ? BalanceTransaction::TYPE_ADMIN_CREDIT : BalanceTransaction::TYPE_ADMIN_DEBIT,
                'amount' => $this->fromCents($delta),
                'balance_after' => $after,
                'reference' => 'admin:'.Str::uuid(),
                'metadata' => [
                    'admin_account_id' => $adminAccountId,
                    'admin_username' => $adminUsername,
                    'reason' => $reason,
                ],
            ]);
        }, 3);
    }

    /** @return Collection<int, BalanceTransaction> */
    public function adminTransactions(?string $search = null, int $limit = 100): Collection
    {
        return BalanceTransaction::query()
            ->leftJoin('account', 'account.id', '=', 'balance_transactions.account_id')
            ->select('balance_transactions.*', 'account.username')
            ->when($search, function ($query, string $search): void {
                $query->where(function ($query) use ($search): void {
                    $query->where('account.username', 'like', '%'.$search.'%');
                    if (ctype_digit($search)) {
                        $query->orWhere('balance_transactions.account_id', (int) $search);
                    }
                });
            })
            ->latest('balance_transactions.id')
            ->limit($limit)
            ->get();
    }

    private function toCents(string $amount): int
    {
        $normalized = str_replace(',', '.', trim($amount));
        if (! preg_match('/^-?\d+(?:\.\d{1,6})?$/', $normalized)) {
            throw new InvalidArgumentException('Некорректная сумма.');
        }

        $negative = str_starts_with($normalized, '-');
        $normalized = ltrim($normalized, '-');
        [$whole, $fraction] = array_pad(explode('.', $normalized, 2), 2, '');
        $cents = ((int) $whole * 100) + (int) str_pad(substr($fraction, 0, 2), 2, '0');

        return $negative ? -$cents : $cents;
    }

    private function fromCents(int $cents): string
    {
        return number_format($cents / 100, 2, '.', '');
    }
}