<?php

namespace App\Services\Wallet;

use App\Models\Tenant;
use App\Models\TenantPaymentSetting;
use App\Models\User;
use App\Models\VoucherAgent;
use App\Models\Wallet;
use App\Models\WalletLedgerEntry;
use App\Models\WalletTransaction;
use App\Models\WalletWithdrawal;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Str;
use Illuminate\Validation\ValidationException;

class WalletService
{
    public function chargeUser(User $user, int $tenantId, float $amount, string $idempotencyKey, string $description): WalletTransaction
    {
        return DB::transaction(function () use ($user, $tenantId, $amount, $idempotencyKey, $description) {
            $existing = WalletTransaction::where('idempotency_key', $idempotencyKey)->first();
            if ($existing) {
                return $existing;
            }

            $wallet = Wallet::lockForUpdate()->find($this->walletFor($user, $tenantId, 'deposit')->id);
            if ((float) $wallet->available_balance < $amount) {
                throw ValidationException::withMessages(['wallet' => 'Saldo deposit agen pada tenant ini tidak mencukupi.']);
            }

            $transaction = WalletTransaction::create([
                'uuid' => Str::uuid(), 'transaction_number' => 'WLT-'.now()->format('YmdHis').'-'.Str::upper(Str::random(6)),
                'type' => 'voucher_purchase', 'status' => 'processing', 'initiated_by' => $user->id,
                'amount' => $amount, 'fee' => 0, 'idempotency_key' => $idempotencyKey, 'description' => $description,
            ]);
            $this->post($wallet, $transaction, 'debit', $amount);
            $transaction->update(['status' => 'completed', 'completed_at' => now()]);

            return $transaction;
        });
    }

    public function wallets(User $user, ?int $tenantId)
    {
        if (! $tenantId) {
            return collect();
        }

        $balances = collect([$this->balanceData($this->walletFor($user, $tenantId, 'deposit'), 'deposit', 'Saldo Deposit')]);
        $usesGlobalGateway = TenantPaymentSetting::where('tenant_id', $tenantId)
            ->where('payment_mode', 'platform_gateway')->whereNotNull('platform_gateway_account_id')->exists();
        if ($usesGlobalGateway && ($user->isMasterAdmin() || $user->isTenantOwner($tenantId))) {
            $balances->push($this->balanceData($this->walletFor(Tenant::findOrFail($tenantId), $tenantId, 'tenant_settlement'), 'tenant_settlement', 'Saldo Settlement Tenant'));
        }

        $agent = VoucherAgent::where('tenant_id', $tenantId)->where('user_id', $user->id)
            ->where('payment_type', 'postpaid')->where('status', 'active')->first();
        if ($agent) {
            $balances->push([
                'id' => "credit-{$agent->id}", 'uuid' => $agent->uuid, 'tenant_id' => $tenantId,
                'wallet_type' => 'voucher_credit', 'balance_kind' => 'credit', 'label' => 'Saldo Kredit Voucher',
                'credit_limit' => $agent->credit_limit, 'used_credit' => $agent->outstanding_balance,
                'remaining_credit' => number_format(max(0, (float) $agent->credit_limit - (float) $agent->outstanding_balance), 2, '.', ''),
                'available_balance' => number_format(max(0, (float) $agent->credit_limit - (float) $agent->outstanding_balance), 2, '.', ''),
                'pending_balance' => '0.00', 'locked_balance' => '0.00', 'currency' => 'IDR',
                'status' => $agent->status, 'ledger_available' => false, 'can_withdraw' => false, 'can_transfer' => false,
                'usage_note' => 'Khusus untuk pembelian voucher hotspot pada tenant ini.',
            ]);
        }

        return $balances->values();
    }

    public function ledger(Wallet $wallet, User $actor, ?int $tenantId, array $filters)
    {
        $this->authorizeWallet($wallet, $actor, $tenantId);

        return $wallet->ledgerEntries()->with('transaction:id,uuid,transaction_number,type,status,description,created_at')
            ->latest('id')->paginate($filters['per_page'] ?? 10);
    }

    public function transfer(Wallet $source, Wallet $destination, float $amount, User $actor, ?int $tenantId): WalletTransaction
    {
        $this->authorizeWallet($source, $actor, $tenantId);
        $this->authorizeWallet($destination, $actor, $tenantId);
        if ((int) $source->tenant_id !== (int) $destination->tenant_id || (int) $source->tenant_id !== (int) $tenantId) {
            throw ValidationException::withMessages(['destination_wallet_id' => 'Saldo tidak dapat dipindahkan antar tenant.']);
        }
        if ($source->is($destination)) {
            throw ValidationException::withMessages(['destination_wallet_id' => 'Dompet tujuan harus berbeda.']);
        }
        if ($amount <= 0) {
            throw ValidationException::withMessages(['amount' => 'Nominal harus lebih dari nol.']);
        }

        return DB::transaction(function () use ($source, $destination, $amount, $actor) {
            $wallets = Wallet::whereIn('id', [$source->id, $destination->id])->lockForUpdate()->get()->keyBy('id');
            $from = $wallets[$source->id];
            $to = $wallets[$destination->id];
            if ((float) $from->available_balance < $amount) {
                throw ValidationException::withMessages(['amount' => 'Saldo tidak mencukupi.']);
            }
            $transaction = $this->newTransaction('transfer', $amount, $actor, 'Pindah saldo antar dompet');
            $this->post($from, $transaction, 'debit', $amount);
            $this->post($to, $transaction, 'credit', $amount);
            $transaction->update(['status' => 'completed', 'completed_at' => now()]);

            return $transaction->load('entries.wallet');
        });
    }

    public function requestWithdrawal(Wallet $wallet, array $data, User $actor, ?int $tenantId): WalletWithdrawal
    {
        $this->authorizeWallet($wallet, $actor, $tenantId);
        if ($wallet->wallet_type !== 'tenant_settlement') {
            throw ValidationException::withMessages(['wallet' => 'Saldo deposit user hanya dapat digunakan untuk transaksi layanan dan tidak dapat ditarik tunai.']);
        }

        return DB::transaction(function () use ($wallet, $data, $actor) {
            $locked = Wallet::lockForUpdate()->findOrFail($wallet->id);
            $total = (float) $data['amount'] + (float) ($data['fee'] ?? 0);
            if ((float) $locked->available_balance < $total) {
                throw ValidationException::withMessages(['amount' => 'Saldo tidak mencukupi.']);
            }
            $transaction = $this->newTransaction('withdrawal', $data['amount'], $actor, 'Permintaan penarikan saldo', $data['fee'] ?? 0);
            $this->post($locked, $transaction, 'debit', $total);

            return WalletWithdrawal::create([
                'uuid' => Str::uuid(), 'wallet_id' => $locked->id, 'wallet_transaction_id' => $transaction->id,
                'requested_by' => $actor->id, 'amount' => $data['amount'], 'fee' => $data['fee'] ?? 0,
                'bank_code' => $data['bank_code'], 'account_number' => $data['account_number'],
                'account_name' => $data['account_name'], 'status' => 'pending_approval',
            ]);
        });
    }

    private function walletFor(Model $owner, int $tenantId, string $type): Wallet
    {
        return Wallet::firstOrCreate(
            ['owner_type' => $owner->getMorphClass(), 'owner_id' => $owner->getKey(), 'tenant_id' => $tenantId, 'wallet_type' => $type, 'currency' => 'IDR'],
            ['uuid' => Str::uuid(), 'status' => 'active']
        );
    }

    private function balanceData(Wallet $wallet, string $kind, string $label): array
    {
        return [
            ...$wallet->toArray(), 'balance_kind' => $kind, 'label' => $label, 'ledger_available' => true,
            'can_withdraw' => $kind === 'tenant_settlement', 'can_transfer' => false,
            'usage_note' => $kind === 'deposit'
                ? 'Dapat digunakan untuk transaksi layanan pada tenant ini.'
                : 'Dana tenant dari transaksi melalui payment gateway global.',
        ];
    }

    private function newTransaction(string $type, float $amount, User $actor, string $description, float $fee = 0): WalletTransaction
    {
        return WalletTransaction::create([
            'uuid' => Str::uuid(), 'transaction_number' => 'WLT-'.now()->format('YmdHis').'-'.Str::upper(Str::random(6)),
            'type' => $type, 'status' => 'processing', 'initiated_by' => $actor->id, 'amount' => $amount,
            'fee' => $fee, 'idempotency_key' => (string) Str::uuid(), 'description' => $description,
        ]);
    }

    private function post(Wallet $wallet, WalletTransaction $transaction, string $type, float $amount): void
    {
        $before = (float) $wallet->available_balance;
        $after = $type === 'credit' ? $before + $amount : $before - $amount;
        WalletLedgerEntry::create([
            'wallet_id' => $wallet->id, 'wallet_transaction_id' => $transaction->id, 'entry_type' => $type,
            'balance_bucket' => 'available', 'amount' => $amount, 'balance_before' => $before,
            'balance_after' => $after, 'description' => $transaction->description,
        ]);
        $wallet->update(['available_balance' => $after, 'version' => $wallet->version + 1]);
    }

    private function authorizeWallet(Wallet $wallet, User $actor, ?int $tenantId): void
    {
        if ($actor->isMasterAdmin()) {
            return;
        }
        $sameTenant = $tenantId && (int) $wallet->tenant_id === (int) $tenantId;
        $allowed = $sameTenant && (($wallet->owner_type === $actor->getMorphClass() && (int) $wallet->owner_id === (int) $actor->id)
            || ($actor->isTenantOwner($tenantId) && $wallet->owner_type === (new Tenant)->getMorphClass() && (int) $wallet->owner_id === (int) $tenantId));
        abort_unless($allowed, 403, 'Saldo tidak dapat diakses.');
    }
}