const path = require('path');
const colors = require('colors');
const fs = require('fs');
const docker = require('docker-compose');

class ProjectEnvironment {
  constructor(cwd, env) {
    this._cwd = cwd;
    this._env = env;

    this._dockerOptions = {
      config: [
        'docker-compose.yml'
      ],
      cwd: cwd,
      log: true
    };

    this._setEnvironment(env);
  }

  _setEnvironment(env) {
    if (
      !this._loadConfigFile() ||
      !this._loadDockerComposeFile()
    ) {
      throw [`Unable to load %s environment`, colors.bold(env)];
    }
  }

  _loadConfigFile() {
    const configFilename = `config.${this._env}.json`;
    const configFilepath = path.join(this._cwd, configFilename);

    if (!fs.existsSync(configFilepath)) {
      return false;
    }

    try {
      const config = JSON.parse(fs.readFileSync(configFilepath, 'utf8'));
      this._config = config;
    } catch (ex) {
      return false;
    }

    return true;
  }

  _loadDockerComposeFile() {
    const dockerComposeFilename = `docker-compose.${this._env}.yml`;
    const dockerComposeFilepath = path.join(this._cwd, dockerComposeFilename);

    if (!fs.existsSync(dockerComposeFilepath)) {
      return false;
    }

    this._dockerOptions.config.push(dockerComposeFilename);

    let envFilename = `.env.${this._env}`;
    let envFilepath = path.join(this._cwd, envFilename);

    if (!fs.existsSync(envFilepath)) {
      envFilename = `.env`;
      envFilepath = path.join(this._cwd, envFilename);

      if (!fs.existsSync(envFilepath)) {
        envFilename = false;
      }
    }

    if (envFilename) {
      this._dockerOptions.composeOptions = [["--env-file", envFilename]];
    }

    return true;
  }

  setDockerOptions(options) {
    this._dockerOptions = { ...this._dockerOptions, ...options };
  }

  getDockerOptions() {
    return this._dockerOptions;
  }

  getCwd() {
    return this._cwd;
  }

  getEnv() {
    return this._env;
  }

  getHosts() {
    return this._config['hosts'] || {};
  }

  async getServices() {
    const data = await docker.configServices({ ...this.getDockerOptions(), ...{ log: false } });

    const services = data.out.split('\n');
    services.pop();

    return services;
  }
}

module.exports = ProjectEnvironment;