declare let global: any;
import fs from 'fs';
import dotenv from 'dotenv';
dotenv.config();

enum Environment {
  localhost = 'localhost',
  experimental = 'experimental',
  develop = 'develop',
  testnet = 'testnet',
  mainnet = 'mainnet',
}

const getEnvironment = (): Environment => {
  if (global.__companionNetwork !== undefined && global.__companionNetwork !== '') {
    return global.__companionNetwork as Environment;
  }

  let environment = Environment.testnet;
  const acceptableBranches: Set<string> = new Set<string>(Object.values(Environment));
  const head = './.git/HEAD';
  const env: string = process.env.ABI_ENVIRONMENT || process.env.HOLOGRAPH_ENVIRONMENT || '';
  if (env === '') {
    if (fs.existsSync(head)) {
      const contents = fs.readFileSync('./.git/HEAD', 'utf8');
      const branch = contents.trim().split('ref: refs/heads/')[1];
      if (acceptableBranches.has(branch)) {
        environment = Environment[branch as keyof typeof Environment];
      }
    }
  } else if (acceptableBranches.has(env)) {
    environment = Environment[env as keyof typeof Environment];
  }

  global.__environment = environment;
  return environment;
};

const setEnvironment = (env?: Environment): Environment => {
  let environment = Environment.testnet;

  if (env !== undefined) {
    const acceptableBranches: Set<string> = new Set<string>(Object.values(Environment));

    if (acceptableBranches.has(env)) {
      environment = Environment[env as keyof typeof Environment];
    }
  }

  global.__environment = environment;
  return environment;
};

export { Environment, getEnvironment, setEnvironment };