'use strict';
////////////////////////////////////////////////////////////////////////////////
/// DISCLAIMER
///
/// Copyright 2013-2014 triAGENS GmbH, Cologne, Germany
/// Copyright 2015 ArangoDB GmbH, Cologne, Germany
///
/// 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.
///
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
///
/// @author Lucas Dohmen
/// @author Alan Plum
////////////////////////////////////////////////////////////////////////////////

const _ = require('lodash');
const joi = require('joi');
const is = require('@arangodb/is');
const toJSONSchema = require('@arangodb/foxx/legacy/schema').toJSONSchema;
const extend = require('@arangodb/extend').extend;
const EventEmitter = require('events').EventEmitter;
const metadataSchema = {
  _id: joi.string().optional(),
  _key: joi.string().optional(),
  _oldRev: joi.string().optional(),
  _rev: joi.string().optional(),
  _from: joi.string().optional(),
  _to: joi.string().optional()
};


////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_initializer
////////////////////////////////////////////////////////////////////////////////

function excludeExtraAttributes(attributes, model) {
  if (!model.schema) {
    return _.clone(attributes);
  }
  return _.omit(attributes, _.difference(
    _.keys(metadataSchema),
    _.keys(model.schema)
  ));
}

function Model(attributes) {

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_attributes
////////////////////////////////////////////////////////////////////////////////

  this.attributes = {};

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_isvalid
////////////////////////////////////////////////////////////////////////////////

  this.isValid = true;

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_errors
////////////////////////////////////////////////////////////////////////////////

  this.errors = {};

  if (this.schema) {
    if (this.schema.isJoi) {
      this.schema = _.object(_.map(this.schema._inner.children, function (prop) {
        return [prop.key, prop.schema];
      }));
    }
    _.each(
      _.union(_.keys(this.schema), _.keys(attributes)),
      function (key) {
        this.set(key, attributes && attributes[key]);
      },
      this
    );
  } else if (attributes) {
    this.attributes = _.clone(attributes);
  }
}

Model.prototype = Object.create(EventEmitter.prototype);
_.extend(Model.prototype, {

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_get
////////////////////////////////////////////////////////////////////////////////

  get(attributeName) {
    return this.attributes[attributeName];
  },

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_set
////////////////////////////////////////////////////////////////////////////////

  set(attributeName, value) {

    if (is.object(attributeName)) {
      _.each(attributeName, function (value, key) {
        this.set(key, value);
      }, this);
      return this;
    }

    if (this.schema) {
      var schema = this.schema[attributeName] || metadataSchema[attributeName] || joi.forbidden();
      var result = schema.validate(value);

      if (result.error) {
        this.errors[attributeName] = result.error;
        this.isValid = false;
      } else {
        delete this.errors[attributeName];
        if (_.isEmpty(this.errors)) {
          this.isValid = true;
        }
      }

      if (result.value === undefined) {
        delete this.attributes[attributeName];
      } else {
        this.attributes[attributeName] = result.value;
      }
    } else {
      this.attributes[attributeName] = value;
    }

    return this;
  },

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_has
////////////////////////////////////////////////////////////////////////////////

  has(attributeName) {
    return !(_.isUndefined(this.attributes[attributeName]) ||
             _.isNull(this.attributes[attributeName]));
  },

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_forDB
////////////////////////////////////////////////////////////////////////////////

  forDB() {
    return this.attributes;
  },

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_forClient
////////////////////////////////////////////////////////////////////////////////

  forClient() {
    return excludeExtraAttributes(this.attributes, this);
  }
});

Model.toJSONSchema = function (id) {
  return toJSONSchema(id, this);
};

Model.fromClient = function (attributes) {
  var model = new this();
  model.set(excludeExtraAttributes(attributes, model));
  return model;
};

////////////////////////////////////////////////////////////////////////////////
/// @brief was docuBlock JSF_foxx_model_extend
////////////////////////////////////////////////////////////////////////////////

Model.extend = extend;

exports.Model = Model;