/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

var validators = require('utils/validator');
var stringUtils = require('utils/string_utils');

/**
 * @typedef {parsedJDBCUrl}
 * @type {object}
 * @property {string} dbType alias name by type of database @see utils/configs/database.DB_UI_TYPE_ALIAS
 * @property {string} location parsed host name
 */

/**
 * Helper methods to process database values and properties
 * @module utils/configs/database
 */
module.exports = {
  /**
   * Database type properties with <code>options</code> attribute usually displayed as radio-button.
   * <code>options</code> attribute contains mapping of database type to special properties name such as
   * database host and database name.
   * @type {object}
   */
  dbServicePropertyMap: {
    HIVE: {
      dbType: 'hive_database',
      databaseName: 'ambari.hive.db.schema.name',
      connectionUrl: 'javax.jdo.option.ConnectionURL'
    },
    OOZIE: {
      dbType: 'oozie_database',
      connectionUrl: 'oozie.service.JPAService.jdbc.url',
      databaseName: 'oozie.db.schema.name'
    },
    RANGER: {
      dbType: 'DB_FLAVOR',
      connectionUrl: 'ranger.jpa.jdbc.url',
      databaseName: 'db_name',
      fallbackHostName: 'db_host'
    }
  },

  /**
   * Map of jdbc url patterns related to supported database types.
   *
   * @type {object}
   */
  DB_JDBC_PATTERNS: {
    mysql: 'jdbc:mysql://{0}/{1}',
    mssql: 'jdbc:sqlserver://{0};databaseName={1}',
    postgres: 'jdbc:postgresql://{0}:5432/{1}',
    derby: 'jdbc:derby:{0}/{1}',
    oracle: 'jdbc:oracle:thin:@(?:\/?\/?){0}:1521(\:|\/){1}',
    sqla: 'jdbc:sqlanywhere:host={0};database={1}'
  },

  DB_UI_TYPE_ALIAS: {
    mysql: 'mysql',
    sqlserver: 'mssql',
    postgresql: 'postgres',
    derby: 'derby',
    oracle: 'oracle',
    sqlanywhere: 'sqla'
  },

  /**
   * Setup database related properties.
   *
   * @method bootstrapDatabaseProperties
   * @param {App.ServiceConfigProperty[]} serviceConfigs
   * @param {string} [serviceName=false]
   */
  bootstrapDatabaseProperties: function(serviceConfigs, serviceName) {
    var self = this;
    var supportedServices = Em.keys(this.dbServicePropertyMap);
    if (serviceName && !supportedServices.contains(serviceName)) return;
    var serviceNames = serviceName ? [serviceName] : serviceConfigs.mapProperty('serviceName').uniq();
    serviceNames.forEach(function(serviceName) {
      if (!supportedServices.contains(serviceName)) return;
      var configs = serviceConfigs.filterProperty('serviceName', serviceName) || [];
      var connectionConfigs = self.dbServicePropertyMap[serviceName];
      var databaseTypeProperty = configs.findProperty('name', connectionConfigs.dbType);
      if (!databaseTypeProperty) return;
      var databaseTypePropertyIndex = configs.indexOf(databaseTypeProperty);
      var generatedProperties = self.getPropsByOptions(databaseTypeProperty, configs);
      var jdbcObject = self.parseJdbcUrl(Em.get(configs.findProperty('name', connectionConfigs.connectionUrl), 'value'));
      generatedProperties.forEach(function(property) {
        if (Em.get(property, 'name').endsWith('_host')) {
          // set UI host names for each database type with value parsed from jdbc connection url
          // if value is not ip or hostname (in case of New Derby Database) for Oozie set <code>fallbackUrl</code>
          // from <code>dbServicePropertyMap</code>
          Em.setProperties(property, {
            value: jdbcObject.location || ''
          });
          self.addPropertyToServiceConfigs(property, serviceConfigs, databaseTypePropertyIndex);
        }
      });
    });
  },

  /**
   * Add UI specific property to serviceConfigObject if it does not exist, and update value for existed property.
   * This code affects properties related to `_host` and `_database` which are hardcoded on UI.
   *
   * @param {object} property - property to append/update
   * @param {App.ServiceConfigProperty[]} configs - loaded and processed service configs
   * @param {integer} index of first occurrence of database type in config
   */
  addPropertyToServiceConfigs: function(property, configs, index) {
    var configProperty = configs.findProperty('name', Em.get(property, 'name'));
    if (configProperty) {
      Em.set(configProperty, 'value', Em.get(property, 'value'));
    } else {
      if (index) {
        configs.insertAt(index, App.ServiceConfigProperty.create(property));
      } else {
        configs.pushObject(App.ServiceConfigProperty.create(property));
      }
    }
  },

  /**
   * Get hardcoded properties from site_properties.js which UI use to display host name and database name.
   *
   * @method getPropsByOptions
   * @param {object} databaseTypeProperty - hardcoded property from site_properties.js usualy used as radiobutton
   * @param {App.ServiceConfigProperty[]} configs - loaded and processed configs
   * @returns {object[]} - hardcoded properties from site_properties.js related to database name and location
   */
  getPropsByOptions: function(databaseTypeProperty) {
    Em.assert('Property related to database type should contains `options` attribute', databaseTypeProperty.get('options'));
    return databaseTypeProperty.options.mapProperty('foreignKeys').reduce(function(p,c) {
      return p.concat(c);
    }).uniq().map(function(name) {
      return App.config.get('preDefinedSiteProperties').findProperty('name', name) || null;
    }).compact();
  },

  /**
   * Get database location from jdbc url value
   *
   * @method getDBLocationFromJDBC
   * @param {string} jdbcUrl - url to parse
   * @returns {string|null}
   */
  getDBLocationFromJDBC: function(jdbcUrl) {
    var dbProvider = this.getJDBCProviderName(jdbcUrl),
        protocol = this._makeProtocol(dbProvider),
        pattern = /^\/\//,
        url;
    if (!this.isSupportedProvider(dbProvider)) {
      return '';
    }
    if (dbProvider === 'derby') {
      return this.getDerbyPath(jdbcUrl);
    }
    url = "http://" + jdbcUrl.replace(protocol, '').replace(pattern, '');
    if (dbProvider === 'sqlserver') {
      url = url.split(';')[0];
    }
    if (dbProvider === 'oracle') {
      var matches = jdbcUrl.replace(protocol, '').match(/@(?:\/?\/?)(.+)/);
      if (matches.length) {
        var result = Em.getWithDefault(matches, '1', '').split(':')[0];
        return result === '{0}' ? '' : result;
      }
      return '';
    }
    if (dbProvider === 'sqlanywhere') {
      url = url.split(';').map(function(i) {
        return /host=/.test(i) ? i.replace('host=', '').replace('http://', '') : null;
      }).compact()[0];
      return this.getHostNameByUrl('http://' + url);
    }
    url = url.split(':').slice(0, 2).join(':');
    return this.getHostNameByUrl(url);
  },


  /**
   * Return derby database path by jdbcUrl
   *
   * @param {string} jdbcUrl
   * @return {string} database path
   */
  getDerbyPath: function(jdbcUrl) {
    var matches = jdbcUrl.match(new RegExp(this.DB_JDBC_PATTERNS['derby'].format('(.*)', '(.*)')));
    if (matches.length) {
      var dbLocation = Em.getWithDefault(matches, '1', '');
      if (dbLocation.startsWith('${')) {
        return Em.getWithDefault(matches, '0', '').match(/\${[^}]+}/)[0];
      }
      return dbLocation != '{0}' ? dbLocation : null;
    } else {
      return null;
    }
  },

  /**
   * Returns host name by url input
   *
   * @param {string} url
   * @returns {string} host name
   */
  getHostNameByUrl: function(url) {
    var link = document.createElement('a');
    link.href = url;
    var hostName = link.hostname;
    link = null;
    return hostName;
  },

  _makeProtocol: function(dbProvider) {
    var protocol = 'jdbc:' + dbProvider + ':';
    if (dbProvider === 'oracle') {
      return protocol + 'thin:';
    }
    return protocol;
  },

  /**
   * Returns provider name from jdbcUrl
   *
   * @param {string} jdbcUrl
   * @returns {string} provider name e.g. `jdbc:some_provider:another-opt//additional` -> `some_provider`
   */
  getJDBCProviderName: function(jdbcUrl) {
    return jdbcUrl.split(':')[1];
  },

  /**
   * Returns true when provider supported by UI.
   *
   * @returns {boolean}
   */
  isSupportedProvider: function(dbProvider) {
    return !!(this.DB_UI_TYPE_ALIAS[dbProvider]);
  },

  /**
   * Determines alias value (DB_UI_TYPE_ALIAS attribute value) by provider name
   *
   * @param {string} dbProvider provider name parsed from jdbcUrl e,g. from `jdbc:mysql://` -> `mysql`
   * @returns {string} alias value used on UI.
   */
  getJDBCAlias: function(dbProvider) {
    return this.DB_UI_TYPE_ALIAS[dbProvider];
  },

  /**
   * Returns parsed info from jdbcUrl connection string
   *
   * @param {string} jdbcUrl
   * @returns {parsedJDBCUrl}
   */
  parseJdbcUrl: function(jdbcUrl) {
    var result = {
      dbType: null,
      location: null
    };
    if (jdbcUrl === '') {
      return result;
    }
    result.dbType = this.getJDBCAlias(this.getJDBCProviderName(jdbcUrl)) || null;
    result.location = this.getDBLocationFromJDBC(jdbcUrl);
    return result;
  }

};