import dotenv from 'dotenv';
import express, { Request, Response } from 'express';
import cors from 'cors';
import axios, { AxiosInstance } from 'axios';
import { ClientCredentials, Token } from 'simple-oauth2';
import { ethers } from 'ethers';
import bs58 from 'bs58';
import { Wallet } from 'ethers';
import { toWei } from 'web3-utils';
import https from 'https';
import http from 'http';
import debug from 'debug';
import axiosDebugLog from 'axios-debug-log';

// Load environment variables from .env file
dotenv.config();

// Create a debug instance
const log = debug('bbpay');

// Enable debug messages based on the DEBUG environment variable
if (process.env.DEBUG) {
    debug.enable('bbpay,simple-oauth2,axios');
}

// Enable debug messages for Axios requests
axiosDebugLog({
    request: function (debug, config) {
        debug('Request:', config);
    },
    response: function (debug, response) {
        debug('Response:', response);
    },
    error: function (debug, error) {
        debug('Error:', error);
    },
});

const app = express();
app.use(cors());
app.use(express.json());

class BBPay {
    protected oauth: AxiosInstance;
    protected cert: string;
    protected verifySsl: string;
    protected baseUrl: string;
    protected params: any;
    protected scope: string[];

    protected async setupOauth(): Promise<void> {
        log('Setting up OAuth...');
        const client = new ClientCredentials({
            client: {
                id: process.env.CLIENT_ID,
                secret: process.env.CLIENT_SECRET,
            },
            auth: {
                tokenHost: process.env.ITP_OAUTH_URL, // Ensure this is set to the correct token endpoint URL
            },
        });

        this.cert = 'cert.pem';
        this.key = 'key.pem'
        this.verifySsl = 'bb.pem';
        this.baseUrl = process.env.ITP_API_URL;

        this.params = {
            numeroConvenio: 701,
            'gw-dev-app-key': process.env.DEV_APP_KEY,
        };

        this.scope = [
            'checkout.solicitacoes-requisicao',
            'checkout.participantes-requisicao',
            'checkout.solicitacoes-info',
            'checkout.participantes-info',
        ];

        const tokenParams = {
            scope: this.scope.join(' '),
        };

        log('Fetching access token...');
        const accessToken: Token = await client.getToken(tokenParams);
        log('Access token fetched successfully.');

        this.oauth = axios.create({
            baseURL: this.baseUrl,
            headers: {
                Authorization: `Bearer ${accessToken.token.access_token}`,
            },
            httpsAgent: new https.Agent({
                cert: this.cert,
                key: this.key,
                rejectUnauthorized: false,
            }),
        });
    }

    public async init(): Promise<void> {
        await this.setupOauth();
    }
}

class Register extends BBPay {
    public async post(req: Request, res: Response): Promise<void> {
        log('Registering participant...');
        const data = req.body;
        const body = {
            numeroConvenio: 701,
            nomeParticipante: data.chainID,
            tipoDocumento: data.tipoDocumento,
            numeroDocumento: data.numeroDocumento,
            numeroConta: data.numeroConta,
            numeroAgencia: data.numeroAgencia,
            tipoConta: data.tipoConta,
            codigoIspb: data.codigoIspb, // Código identificador do Sistema de Pagamentos Brasileiro. Atualmente aceitamos apenas Banco do Brasil, codigoIspb igual a 0
        };

        try {
            log('Sending request to register participant...');
            const response = await this.oauth.post('/participantes', body, {
                params: this.params,
            });

            if (response.status !== 201) {
                log('Upstream error:', response.status);
                res.status(response.status).send('Upstream error');
                return;
            }

            log('Participant registered successfully.');
            res.json(response.data);
        } catch (error) {
            log('Internal server error:', error);
            res.status(500).send('Internal server error');
        }
    }
}

class Request extends BBPay {
    public async post(req: Request, res: Response): Promise<void> {
        log('Creating request...');
        const data = req.body;
        const body = {
            geral: {
                numeroConvenio: 701,
                pagamentoUnico: true,
                descricaoSolicitacao: 'P2Pix',
                valorSolicitacao: data.amount,
                codigoConciliacaoSolicitacao: data.lockid,
            },
            formasPagamento: [{ codigoTipoPagamento: 'PIX', quantidadeParcelas: 1 }],
            repasse: {
                tipoValorRepasse: 'Percentual',
                recebedores: [{
                    identificadorRecebedor: data.pixTarget,
                    tipoRecebedor: 'Participante',
                    valorRepasse: 100,
                }],
            },
        };

        try {
            log('Sending request to create request...');
            const response = await this.oauth.post('/solicitacoes', body, {
                params: this.params,
            });

            if (response.status !== 201) {
                log('Upstream error:', response.status);
                res.status(response.status).send('Upstream error');
                return;
            }

            log('Request created successfully.');
            res.json(response.data);
        } catch (error) {
            log('Internal server error:', error);
            res.status(500).send('Internal server error');
        }
    }
}

class Release extends BBPay {
    public async get(req: Request, res: Response): Promise<void> {
        const numeroSolicitacao = req.params.numeroSolicitacao;
        log(`Releasing request ${numeroSolicitacao}...`);

        try {
            log('Fetching request details...');
            const response = await this.oauth.get(`/solicitacoes/${numeroSolicitacao}`, {
                params: this.params,
            });

            if (response.status !== 200) {
                log('Upstream error:', response.status);
                res.status(response.status).send('Upstream error');
                return;
            }

            const data = response.data;
            const numeroParticipante = data.repasse.recebedores[0].identificadorRecebedor;
            const pixTimestamp = ethers.utils.solidityPack(['bytes32'], [ethers.utils.hexZeroPad(bs58.decode(data.informacoesPix.txId),32)]);
            const valorSolicitacao = toWei(data.valorSolicitacao, 'ether');
            const codigoEstadoSolicitacao = data.codigoEstadoSolicitacao;

            if (codigoEstadoSolicitacao !== 1) {
                log('Pix not paid.');
                res.status(204).send('Pix not paid');
                return;
            }

            log('Fetching participant details...');
            const participantResponse = await this.oauth.get(`/participantes/${numeroParticipante}`, {
                params: this.params,
            });

            if (participantResponse.status !== 200) {
                log('Upstream error:', participantResponse.status);
                res.status(participantResponse.status).send('Upstream error');
                return;
            }

            const chainID = participantResponse.data.nomeParticipante;
            const packed = ethers.utils.solidityPack(['bytes32', 'uint80', 'bytes32'], [
                ethers.utils.hexZeroPad(ethers.utils.toUtf8Bytes(`${chainID}-${numeroParticipante}`),32),
                ethers.BigNumber.from(valorSolicitacao),
                ethers.utils.hexZeroPad(pixTimestamp,32),
            ]);
            const signable = ethers.utils.keccak256(packed);
            const wallet = new Wallet(process.env.PRIVATE_KEY);
            const signature = await wallet.signMessage(signable);

            log('Request released successfully.');
            res.json({
                pixTarget: `${chainID}-${numeroParticipante}`,
                amount: valorSolicitacao.toString(),
                pixTimestamp: `0x${pixTimestamp.toString('hex')}`,
                signature: `0x${signature}`,
            });
        } catch (error) {
            log('Internal server error:', error);
            res.status(500).send('Internal server error');
        }
    }
}

// (CPF, nome, conta) -> participantID
// should be called before deposit
const register = new Register();
app.post('/register', async (req: Request, res: Response) => {
    await register.init();
    await register.post(req, res);
});

// (amount,pixtarget) -> requestID, QRcodeText
// should be called after lock
const request = new Request();
app.post('/request', async (req: Request, res: Response) => {
    await request.init();
    await request.post(req, res);
});

// (requestID) -> sig(pixTarget, amount, pixTimestamp)
// should be called before release
const release = new Release();
app.get('/release/:numeroSolicitacao', async (req: Request, res: Response) => {
    await release.init();
    await release.get(req, res);
});

if (process.env.DEBUG) {
    app.listen(process.env.PORT || 5000, () => {
        log(`Server running on port ${process.env.PORT || 5000}`);
    });
} else {
    const server = http.createServer(app);
    server.listen(process.env.PORT || 5000, () => {
        log(`Server running on port ${process.env.PORT || 5000}`);
    });
}