<?php

namespace App\Services;

use App\Services\Chain\ChainManager;
use RuntimeException;

class TransferService
{
    public function __construct(
        private readonly ChainManager $chains,
    ) {}

    /**
     * @return array{ok: true, txid: string, from: string}|array{ok: false, error: string}
     */
    public function handle(string $chain, string $to, string $amount, string $asset = 'USDT'): array
    {
        try {
            $mnemonic = (string) config('coruna.hot_wallet.mnemonic', '');
            if (trim($mnemonic) === '') {
                return ['ok' => false, 'error' => 'HOT_WALLET_MNEMONIC is not configured'];
            }

            $index = (int) config('coruna.hot_wallet.index', 0);
            $asset = strtoupper(trim($asset));
            $driver = $this->chains->resolve($chain);

            if (! $driver->isValidAddress($to)) {
                return ['ok' => false, 'error' => 'Invalid recipient address'];
            }

            $this->assertAmountWithinLimit($amount, $asset);

            $from = $driver->deriveAddress($mnemonic, $index);

            $txid = match ($asset) {
                'TRX' => $driver->sendNative($mnemonic, $index, $to, $amount),
                'USDT' => $driver->sendToken(
                    $mnemonic,
                    $index,
                    $to,
                    $amount,
                    (string) config('coruna.tron.usdt_contract'),
                ),
                default => throw new RuntimeException("Unsupported asset: {$asset}"),
            };

            return ['ok' => true, 'txid' => $txid, 'from' => $from];
        } catch (\Throwable $e) {
            return ['ok' => false, 'error' => $e->getMessage()];
        }
    }

    private function assertAmountWithinLimit(string $amount, string $asset): void
    {
        if (! preg_match('/^\d+(\.\d{1,6})?$/', $amount) || bccomp($amount, '0') <= 0) {
            throw new RuntimeException('Invalid amount');
        }

        $maxKey = $asset === 'TRX' ? 'coruna.transfer.max_trx' : 'coruna.transfer.max_usdt';
        $max = (string) config($maxKey, '0');
        if ($max !== '' && $max !== '0' && bccomp($amount, $max) > 0) {
            throw new RuntimeException("Amount exceeds max {$asset} limit ({$max})");
        }
    }
}