import fetch from 'node-fetch';

export default class Lndhub {
  constructor (baseUrl) {
    this.baseUrl = baseUrl;
  }

  async callEndpoint (method, path, payload) {
    const options = { method, headers: { 'Content-Type': 'application/json' } };

    if (path !== '/auth') {
      options.headers['Authorization'] = `Bearer ${this.accessToken}`;
    }
    if (typeof payload !== 'undefined') {
      options.body = JSON.stringify(payload);
    }

    const res = await fetch(`${this.baseUrl}${path}`, options);
    return res.json();
  }

  async handleErroredRequest (result, retryFunction, args=[]) {
    console.warn('API request failed:', result.message);
    if (result.code === 1) {
      return this.reauth().then(connected => {
        if (connected) {
          console.warn('Lndhub reconnected, trying again...');
          return this[retryFunction](...args);
        }
      });
    } else {
      return false;
    }
  }

  async auth (username, password) {
    const payload = { "login": username, "password": password };
    const data = await this.callEndpoint('post', '/auth', payload);

    if (data.error) {
      console.warn('Lndhub connection failed:', data.message);
      return false;
    } else {
      this.refreshToken = data.refresh_token;
      this.accessToken = data.access_token;
      return true;
    }
  }

  async reauth (refreshToken) {
    const payload = { "refresh_token": this.refreshToken };
    const data = await this.callEndpoint('post', '/auth', payload);

    if (data.error) {
      console.warn('Lndhub re-auth failed:', data.message);
      return false;
    } else {
      if (this.accessToken !== data.access_token) {
        console.log('Lndhub access token refreshed');
      }
      this.accessToken = data.access_token;
      return true;
    }
  }

  async createInvoice (amount, description) {
    const payload = { amount, description };
    let data = await this.callEndpoint('post', '/v2/invoices', payload);

    if (data.error) {
      return this.handleErroredRequest(data, 'createInvoice', Array.from(arguments));
    } else {
      return data;
    }
  }

  async getInvoice (paymentHash) {
    const data = await this.callEndpoint('get', `/v2/invoices/${paymentHash}`);

    if (data.error) {
      return this.handleErroredRequest(data, 'getInvoice', Array.from(arguments));
    } else {
      return data;
    }
  }
}