const express = require('express');
const bodyParser = require('body-parser');
const cors = require('cors');
const fs = require('fs');
const path = require('path');
const Wallet = require('ethereumjs-wallet').default;
const client = require('./client');
const app = express();

app.use(cors());
app.use(bodyParser.json());

const CHAIN_ID = '14006'; // Definisikan Chain ID di sini
const WALLET_DB_PATH = path.join(__dirname, 'wallets.json');

// Fungsi untuk membaca database wallet dari file JSON
function readWalletsDB() {
    return new Promise((resolve, reject) => {
        fs.readFile(WALLET_DB_PATH, 'utf8', (err, data) => {
            if (err) {
                return reject(err);
            }
            resolve(JSON.parse(data));
        });
    });
}

// Fungsi untuk menulis database wallet ke file JSON
function writeWalletsDB(wallets) {
    return new Promise((resolve, reject) => {
        fs.writeFile(WALLET_DB_PATH, JSON.stringify(wallets, null, 2), 'utf8', (err) => {
            if (err) {
                return reject(err);
            }
            resolve();
        });
    });
}

// Fungsi untuk membuat wallet acak
function createRandomWallet() {
    const wallet = Wallet.generate();
    return {
        address: wallet.getAddressString(),
        privateKey: wallet.getPrivateKeyString(),
        balance: '0x0'
    };
}

app.post('/blockchain', async (req, res) => {
    const { method, params, id } = req.body;

    console.log('Received request:', req.body);

    if (method === 'GetChainId') {
        client.GetChainId({}, (error, response) => {
            if (error) {
                console.error('Error in GetChainId:', error);
                res.status(500).json({
                    jsonrpc: '2.0',
                    error: {
                        code: -32603,
                        message: 'Internal JSON-RPC error',
                        data: error.message
                    },
                    id: id
                });
            } else {
                console.log('GetChainId response:', response);
                res.json({
                    jsonrpc: '2.0',
                    result: { chainId: response.chainId },
                    id: id
                });
            }
        });
    } else if (method === 'eth_chainId') {
        console.log('Handling eth_chainId method');
        res.json({
            jsonrpc: '2.0',
            result: `0x${parseInt(CHAIN_ID).toString(16)}`, // Kembalikan Chain ID dalam format heksadesimal
            id: id
        });
    } else if (method === 'eth_blockNumber') {
        console.log('Handling eth_blockNumber method');
        // Kembalikan block number, sebagai contoh kita akan mengembalikan nilai statis
        res.json({
            jsonrpc: '2.0',
            result: '0x1', // Kembalikan block number dalam format heksadesimal
            id: id
        });
    } else if (method === 'net_version') {
        console.log('Handling net_version method');
        res.json({
            jsonrpc: '2.0',
            result: CHAIN_ID, // Kembalikan Chain ID
            id: id
        });
    } else if (method === 'eth_getBalance') {
        console.log('Handling eth_getBalance method');
        const [address, block] = params;
        try {
            const walletsDB = await readWalletsDB();
            const wallet = walletsDB.wallets.find(w => w.address.toLowerCase() === address.toLowerCase());
            if (wallet) {
                res.json({
                    jsonrpc: '2.0',
                    result: wallet.balance, // Kembalikan balance dalam format heksadesimal
                    id: id
                });
            } else {
                res.status(404).json({
                    jsonrpc: '2.0',
                    error: {
                        code: -32602,
                        message: 'Address not found'
                    },
                    id: id
                });
            }
        } catch (error) {
            console.error('Error in eth_getBalance:', error);
            res.status(500).json({
                jsonrpc: '2.0',
                error: {
                    code: -32603,
                    message: 'Internal JSON-RPC error',
                    data: error.message
                },
                id: id
            });
        }
    } else if (method === 'eth_getBlockByNumber') {
        console.log('Handling eth_getBlockByNumber method');
        // Kembalikan block, sebagai contoh ini akan mengembalikan nilai statis
        res.json({
            jsonrpc: '2.0',
            result: {
                number: '0x1',
                hash: '0x0',
                parentHash: '0x0',
                nonce: '0x0',
                sha3Uncles: '0x0',
                logsBloom: '0x0',
                transactionsRoot: '0x0',
                stateRoot: '0x0',
                receiptsRoot: '0x0',
                miner: '0x0',
                difficulty: '0x0',
                totalDifficulty: '0x0',
                extraData: '0x0',
                size: '0x0',
                gasLimit: '0x0',
                gasUsed: '0x0',
                timestamp: '0x0',
                transactions: [],
                uncles: []
            }, // Kembalikan block dalam format JSON
            id: id
        });
    } else if (method === 'addWallets') {
        console.log('Handling addWallets method');
        const [numberOfWallets] = params;
        try {
            const walletsDB = await readWalletsDB();
            for (let i = 0; i < numberOfWallets; i++) {
                const newWallet = createRandomWallet();
                walletsDB.wallets.push(newWallet);
            }
            await writeWalletsDB(walletsDB);
            res.json({
                jsonrpc: '2.0',
                result: `${numberOfWallets} wallets added successfully`,
                id: id
            });
        } catch (error) {
            console.error('Error in addWallets:', error);
            res.status(500).json({
                jsonrpc: '2.0',
                error: {
                    code: -32603,
                    message: 'Internal JSON-RPC error',
                    data: error.message
                },
                id: id
            });
        }
    } else if (method === 'addBalance') {
        console.log('Handling addBalance method');
        const [address, amount] = params;
        try {
            const walletsDB = await readWalletsDB();
            const wallet = walletsDB.wallets.find(w => w.address.toLowerCase() === address.toLowerCase());
            if (wallet) {
                // Konversi saldo dari desimal ke heksadesimal (sebaiknya jika di perlukan untuk pengembangan lebih lanjut gunkan hexadesimal untuk kedua nya)
                const amountInHex = BigInt(amount).toString(16);
                wallet.balance = (BigInt(wallet.balance) + BigInt('0x' + amountInHex)).toString(16);
                await writeWalletsDB(walletsDB);
                res.json({
                    jsonrpc: '2.0',
                    result: `Balance added successfully`,
                    id: id
                });
            } else {
                res.status(404).json({
                    jsonrpc: '2.0',
                    error: {
                        code: -32602,
                        message: 'Address not found'
                    },
                    id: id
                });
            }
        } catch (error) {
            console.error('Error in addBalance:', error);
            res.status(500).json({
                jsonrpc: '2.0',
                error: {
                    code: -32603,
                    message: 'Internal JSON-RPC error',
                    data: error.message
                },
                id: id
            });
        }
    } else if (method === 'eth_gasPrice') {
        console.log('Handling eth_gasPrice method');
        // Implementasi untuk mengembalikan gas price(bebas tetapi lebih baik gunkan konversi gwei)., misalnya:
        res.json({
            jsonrpc: '2.0',
            result: '0x12a05f200', // Contoh gas price dalam format heksadesimal
            id: id
        });
    } else if (method === 'eth_estimateGas') {
        console.log('Handling eth_estimateGas method');
        // Implementasi untuk menghitung estimate gas, misalnya:
        res.json({
            jsonrpc: '2.0',
            result: '0x5208', // Contoh estimate gas dalam format heksadesimal
            id: id
        });
    } else if (method === 'eth_getTransactionCount') {
        console.log('Handling eth_getTransactionCount method');
        const [address, block] = params;
        // Implementasi untuk mengembalikan transaction count, misalnya:
        res.json({
            jsonrpc: '2.0',
            result: '0x1', // Contoh transaction count dalam format heksadesimal
            id: id
        });
    }



});

app.listen(8000, () => {
    console.log('Server HTTP berjalan di port 8000');
});