/**
 * Copyright 2017 Oursky Ltd.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import chalk from 'chalk';
import inquirer from 'inquirer';
import _ from 'lodash';

import { controller } from '../api';
import * as config from '../config';
import { Arguments, createCommand } from '../util';

const emailPrompt: inquirer.Question = {
  type: 'input',
  name: 'email',
  message: 'Email:',
  validate: (input) => {
    if (input.trim() === '') {
      return 'Email is required.';
    }
    if (input.indexOf('@') === -1) {
      return 'Email is not valid (must contains @).';
    }
    return true;
  }
};

const passwordPrompt: inquirer.Question = {
  type: 'password',
  name: 'password',
  message: 'Password:',
  validate: (input) => {
    if (input === '') {
      return 'Password is required.';
    }
    return true;
  }
};

function askCredentials(argv: Arguments) {
  const prompts = [];
  const credentials = {
    email: argv.email,
    password: argv.password
  };

  if (credentials.email) {
    console.log(`Logging in as ${credentials.email}.`);
  } else {
    prompts.push(emailPrompt);
  }

  if (!credentials.password) {
    prompts.push(passwordPrompt);
  }

  if (prompts.length === 0) {
    return Promise.resolve(credentials);
  }

  return inquirer.prompt(prompts).then((answers) => {
    return {
      ...credentials,
      ...answers
    };
  });
}

function saveAccount(
  email: string,
  token: string,
  environment: string,
  local: boolean = false
) {
  const accountKey = _.replace(`${environment}:${email}`, /\./g, '~');

  const setFn = local ? config.setLocal : config.set;
  setFn(['accounts', accountKey], {
    token,
    environment,
    email
  });
  setFn('account', accountKey);
}

function run(argv: Arguments) {
  let email: string;

  return askCredentials(argv)
    .then((answers) => {
      email = answers.email;
      return controller.login(answers.email, answers.password);
    })
    .then(
      (payload) => {
        if (argv.debug) {
          console.log(payload);
        }
        if (payload.non_field_errors) {
          return Promise.reject(payload.non_field_errors);
        }

        saveAccount(email, payload.token, argv.environment, argv.local);
        console.log(chalk.green(`Logged in as ${email}.`));
      },
      (error) => {
        if (argv.debug) {
          console.error(error);
        }
        return Promise.reject('Unable to complete the request.');
      }
    );
}

export default createCommand({
  command: 'login [email]',
  describe: 'Log in to Skygear Portal',
  builder: (yargs) => {
    return yargs
      .option('local', {
        type: 'boolean',
        desc: config.developerMode && 'Configure account for local directory.'
      })
      .option('email', {
        alias: 'e',
        type: 'string',
        desc: 'Email address to login to Skygear Portal.'
      })
      .option('password', {
        alias: 'p',
        type: 'string',
        desc: `Password to login to Skygear Portal.
Suggestion: Use SKYCLI_PASSWORD to specify account password instead.`
      });
  },
  handler: run
});