'use strict';

/**
 * Action: StageCreate
 * - Creates new stage, and new region in that stage for your project.
 * - Creates a new project S3 bucket for the new region and puts env and CF files
 * - Creates CF stack by default, unless noExeCf option is set to true
 * - Updates the project's s-project.json file with the new stage and region
 *
 * Options:
 * - stage                (String) the name of the new stage
 * - region               (String) the name of the new region in the provided stage
 */

module.exports = function(SPlugin, serverlessPath) {

  const path     = require('path'),
    SError     = require(path.join(serverlessPath, 'ServerlessError')),
    SCli       = require(path.join(serverlessPath, 'utils/cli')),
    os         = require('os'),
    fs         = require('fs'),
    BbPromise  = require('bluebird'),
    awsMisc    = require(path.join(serverlessPath, 'utils/aws/Misc')),
    SUtils     = require(path.join(serverlessPath, 'utils'));

  BbPromise.promisifyAll(fs);

  /**
   * StageCreate Class
   */

  class StageCreate extends SPlugin {

    constructor(S, config) {
      super(S, config);
    }

    static getName() {
      return 'serverless.core.' + StageCreate.name;
    }

    registerActions() {
      this.S.addAction(this.stageCreate.bind(this), {
        handler:       'stageCreate',
        description:   `Creates new stage for project
usage: serverless stage create`,
        context:       'stage',
        contextAction: 'create',
        options:       [
          {
            option:      'region',
            shortcut:    'r',
            description: 'AWS lambda supported region for your new stage.'
          },
          {
            option:      'stage',
            shortcut:    's',
            description: 'new stage name.'
          }
        ]
      });

      return BbPromise.resolve();
    }

    /**
     * Action
     */

    stageCreate(evt) {

      let _this    = this;
      _this.evt    = evt;

      // Flow
      return _this._prompt()
        .bind(_this)
        .then(_this._validateAndPrepare)
        .then(function() {

          // Status
          SCli.log('Creating stage and its first region: ' + _this.evt.options.stage + ' - ' + _this.evt.options.region);
        })
        .then(_this._createStage)
        .then(_this._createRegion)
        .then(function() {

          /**
           * Return EVT
           */

          return _this.evt;
        });
    }

    /**
     * Prompt stage and region
     */

    _prompt() {

      let _this = this,
        overrides = {};

      // Skip if non-interactive or stage is provided
      if (!_this.S.config.interactive || (_this.evt.options.stage && _this.evt.options.region)) return BbPromise.resolve();

      ['stage'].forEach(memberVarKey => {
        overrides[memberVarKey] = _this.evt.options[memberVarKey];
      });

      let prompts = {
        properties: {}
      };

      prompts.properties.stage = {
        description: 'Enter a new stage name for this project: '.yellow,
        required:    true,
        message:     'Stage must be letters and numbers only',
        conform:     function(stage) {
          return SUtils.isStageNameValid(stage);
        }
      };

      return _this.cliPromptInput(prompts, overrides)
        .then(function(answers) {
          _this.evt.options.stage = answers.stage.toLowerCase();
          BbPromise.resolve();
        })
        .then(function(){
          return _this.cliPromptSelectRegion('Select a region for your new stage: ', false, false, _this.evt.options.region, false)
            .then(region => {
              _this.evt.options.region = region;
              BbPromise.resolve();
            });
        });
    }

    /**
     * Validate & Prepare
     * - Validate all data from event, interactive CLI or non interactive CLI
     * and prepare data
     */

    _validateAndPrepare() {

      // Check Params
      if (!this.evt.options.stage || !this.evt.options.region) {
        return BbPromise.reject(new SError('Missing stage or region'));
      }

      // Validate Stage
      if (!SUtils.isStageNameValid(this.evt.options.stage)) {
        return BbPromise.reject(new SError('Invalid stage name. Stage must be lowercase letters and numbers only.'));
      }

      // Validate Stage: Ensure stage isn't "local"
      if (this.evt.options.stage == 'local') {
        return BbPromise.reject(new SError('Stage ' + this.evt.options.stage + ' is reserved'));
      }

      // Validate stage: Ensure stage doesn't already exist
      if (this.S.state.validateStageExists(this.evt.options.stage)) {
        return BbPromise.reject(new SError('Stage ' + this.evt.options.stage + ' already exists'));
      }

      // Validate region
      if (awsMisc.validLambdaRegions.indexOf(this.evt.options.region) == -1) {
        return BbPromise.reject(new SError('Invalid region. Lambda not supported in ' + this.evt.options.region));
      }

      return BbPromise.resolve();
    }

    /**
     * Create Stage
     */

    _createStage() {

      let _this = this;

      // Update Meta
      _this.meta = _this.S.state.getMeta();

      _this.meta.stages[_this.evt.options.stage] = {
        regions:   {},
        variables: {
          stage: _this.evt.options.stage
        }
      };

      // Save Meta before adding region
      return _this.meta.save()
      .then(function() {

        // Status
        SCli.log('Successfully created stage "' + _this.evt.options.stage + '"');
      });
    }

    /**
     * Create Region
     * - Call RegionCreate Action
     */

    _createRegion() {

      let _this = this;

      let evt = {
        options: {
          stage: _this.evt.options.stage,
          region: _this.evt.options.region,
          subaction: true
        }
      };

      return _this.S.actions.regionCreate(evt);
    }
  }

  return( StageCreate );
};