src/recink.js

'use strict';

const path = require('path');
const merge = require('merge');
const Emitter = require('./emitter');
const events = require('./events');
const logger = require('./logger');
const Container = require('./container');
const configFactory = require('./config/factory');
const AbstractComponent = require('./component/abstract-component');

/**
 * Recink entry point
 */
class Recink extends Emitter {
  constructor() {
    super();
    
    this._config = {};
    this._components = [];
    this._container = new Container();
    this._registerDebugers();
  }
  
  /**
   * @private
   */
  _registerDebugers() {
    this.on(events.config.load, (container, configFile) => {
      logger.info(logger.emoji.smiley, `Load config from ${ configFile }`);
      logger.debug(container.dump());
    });
    
    this.on(events.components.load, (...components) => {
      logger.debug(
        'Loading components -', components.map(c => c.name).join(', ') || 'None'
      );
    });
    
    this.on(events.component.load, component => {
      logger.debug(`Load component ${ component.name }`);
    });
    
    this.on(events.component.subscribe, component => {
      logger.debug(`Component ${ component.name } is subscribed`);
    });
    
    this.on(events.component.ready, component => {
      logger.debug(`Component ${ component.name } is ready`);
    });
    
    this.on(events.components.run, (...components) => {
      components.map(component => {
        logger.info(
          component.isActive ? logger.emoji.check : logger.emoji.cross,
          `${ component.name.toUpperCase() } component`
        );
      });
    });
  }
  
  /**
   * @returns {Promise}
   */
  run() {
    this.emit(events.components.run, ...this._components);
    
    const activeComponents = this._components.filter(component => component.isActive);

    if (activeComponents.length <= 0) {
      return Promise.resolve();
    }

    return Promise.all(activeComponents.map(component => {
      this.emit(events.component.init, component);
      
      return component.init(this);
    }))
      .then(() => {
        return Promise.all(activeComponents.map(component => {
          this.emit(events.component.run, component);
        
          return component.run(this);
        }));
      })
      .then(() => {
        return Promise.all(this._components.map(component => {
          this.emit(events.component.teardown, component);
        
          return component.teardown(this);
        }));
      });
  }
  
  /**
   * @param {Function} targetClass
   * @returns {string|null}
   * @private
   */
  _getBaseClass(targetClass) {
    if (targetClass instanceof Function) {
      let baseClass = targetClass;

      while (baseClass) {
        const newBaseClass = Object.getPrototypeOf(baseClass);

        if (newBaseClass && newBaseClass !== Object && newBaseClass.name) {
          baseClass = newBaseClass;
        } else {
          break;
        }
      }

      return baseClass.name;
    }
    
    return null;
  }
  
  /**
   * @param {AbstractComponent} components
   * @returns {Promise}
   */
  components(...components) {
    this.emit(events.components.load, ...components);

    if (components.length <= 0) {
      return Promise.resolve();
    }

    return Promise.all(components.map(component => {
      if (!(component instanceof AbstractComponent)
        && [ 'ConfigBasedComponent', 'AbstractComponent' ]
          .indexOf(this._getBaseClass(component.constructor)) === -1) {
        
        return Promise.reject(new Error(
          `Component ${ component.constructor.name } should be an instance of AbstractComponent`
        ));
      }

      component.setLogger(logger);
      this._components.push(component);
      this.emit(events.component.load, component);

      return component.subscribe(this)
        .then(() => {
          return this.emit(events.component.subscribe, component, this);
        })
        .then(() => component.ready())
        .then(() => {
          this.emit(events.component.ready, component);
          return Promise.resolve(component);
        });
    }));
  }
  
  /**
   * @param {string} configFile
   * @param {*} extendConfigs
   * @returns {Promise}
   */
  configureExtend(configFile, ...extendConfigs) {
    if (extendConfigs.length <= 0) {
      return this.configure(configFile);
    }
    
    const promises = extendConfigs
      .concat([ configFile ])
      .map(cfgFile => configFactory.guess(cfgFile).load());

    return Promise.all(promises).then(configVectors => {
      return Promise.resolve(merge.recursive(true, ...configVectors));
    });
  }

  /**
   * @param {string} configFile
   * @returns {Promise}
   */
  configure(configFile = Recink.CONFIG_FILE) {
    return configFactory.guess(configFile).load().then(config => Promise.resolve(config));
  }

  /**
   * @param {Object} config
   * @param {String} configFile
   * @returns {Promise}
   */
  configLoad(config, configFile) {
    return this.emitBlocking(events.config.preprocess, config).then(() => {
      this._config = config;
      this._container.reload(this._config);
      this.emit(events.config.load, this.container, configFile);

      return Promise.resolve(this._config);
    });
  }

  /**
   * @param {string} name
   *
   * @returns {AbstractComponent}
   */
  component(name) {
    return this._components.filter(c => c.name === name)[0] || null;
  }
  
  /**
   * @returns {AbstractComponent[]}
   */
  listComponents() {
    return this._components;
  }

  /**
   * @returns {Container}
   */
  get container() {
    return this._container;
  }

  /**
   * @returns {AbstractConfig}
   */
  get config() {
    return this._config;
  }

  /**
   * @returns {string}
   */
  static get CONFIG_FILE() {
    return path.resolve(process.cwd(), this.CONFIG_FILE_NAME);
  }

  /**
   * @returns {string}
   */
  static get CONFIG_FILE_NAME() {
    return '.recink.yml';
  }
}

module.exports = Recink;