"use strict";

var Utils = require('./utils')
  , Instance = require('./instance')
  , Attribute = require('./model/attribute')
  , Association = require('./associations/base')
  , DataTypes = require('./data-types')
  , Util = require('util')
  , SqlString = require('./sql-string')
  , Transaction = require('./transaction')
  , Promise = require('./promise')
  , QueryTypes = require('./query-types')
  , Hooks = require('./hooks')
  , _ = require('lodash')
  , associationsMixin = require('./associations/mixin');

module.exports = (function() {
  /**
   * A Model represents a table in the database. Sometimes you might also see it refererred to as model, or simply as factory. This class should _not_ be instantiated directly, it is created using `sequelize.define`, and already created models can be loaded using `sequelize.import`
   *
   * @class Model
   * @mixes Hooks
   * @mixes Associations
   */
  var Model = function(name, attributes, options) {
    this.options = Utils._.extend({
      timestamps: true,
      createdAt: 'createdAt',
      updatedAt: 'updatedAt',
      deletedAt: 'deletedAt',
      instanceMethods: {},
      classMethods: {},
      validate: {},
      freezeTableName: false,
      underscored: false,
      underscoredAll: false,
      paranoid: false,
      whereCollection: null,
      schema: null,
      schemaDelimiter: '',
      defaultScope: null,
      scopes: null,
      hooks: {}
    }, options || {});

    this.associations = {};
    this.modelManager = this.daoFactoryManager = null;
    this.name = name;
    this.options.hooks = _.mapValues(this.replaceHookAliases(this.options.hooks), function (hooks) {
      if (!Array.isArray(hooks)) hooks = [hooks];
      return hooks;
    });

    this.scopeObj = {};
    this.sequelize = options.sequelize;
    this.underscored = this.underscored || this.underscoredAll;

    if (!this.options.tableName) {
      this.tableName = this.options.freezeTableName ? name : Utils._.underscoredIf(Utils.pluralize(name), this.options.underscoredAll);
    } else {
      this.tableName = this.options.tableName;
    }

    // error check options
    Utils._.each(options.validate, function(validator, validatorType) {
      if (Utils._.contains(Utils._.keys(attributes), validatorType)) {
        throw new Error('A model validator function must not have the same name as a field. Model: ' + name + ', field/validation name: ' + validatorType);
      }

      if (!Utils._.isFunction(validator)) {
        throw new Error('Members of the validate option must be functions. Model: ' + name + ', error with validate member ' + validatorType);
      }
    });

    this.attributes = this.rawAttributes = Utils._.mapValues(attributes, function(attribute, name) {
      if (!Utils._.isPlainObject(attribute)) {
        attribute = { type: attribute };
      }
      attribute = this.sequelize.normalizeAttribute(attribute);

      if (attribute.references instanceof Model) {
        attribute.references = attribute.references.tableName;
      }

      if (attribute.type === undefined) {
        throw new Error('Unrecognized data type for field ' + name);
      }

      if (attribute.type instanceof DataTypes.ENUM) {
        if (!attribute.values.length) {
          throw new Error('Values for ENUM haven\'t been defined.');
        }

        attribute.validate = attribute.validate || {
          _checkEnum: function(value, next) {
            var hasValue = value !== undefined
              , isMySQL = ['mysql', 'mariadb'].indexOf(options.sequelize.options.dialect) !== -1
              , ciCollation = !!options.collate && options.collate.match(/_ci$/i) !== null
              , valueOutOfScope;

            if (isMySQL && ciCollation && hasValue) {
              var scopeIndex = (attributes[name].values || []).map(function(d) { return d.toLowerCase(); }).indexOf(value.toLowerCase());
              valueOutOfScope = scopeIndex === -1;
            } else {
              valueOutOfScope = ((attributes[name].values || []).indexOf(value) === -1);
            }

            if (hasValue && valueOutOfScope && attributes[name].allowNull !== true) {
              return next('Value "' + value + '" for ENUM ' + name + ' is out of allowed scope. Allowed values: ' + attributes[name].values.join(', '));
            }
            next();
          }
        };
      }

      return attribute;
    }, this);
  };

  Object.defineProperty(Model.prototype, 'QueryInterface', {
    get: function() { return this.modelManager.sequelize.getQueryInterface(); }
  });

  Object.defineProperty(Model.prototype, 'QueryGenerator', {
    get: function() { return this.QueryInterface.QueryGenerator; }
  });

  Model.prototype.toString = function () {
    return '[object SequelizeModel]';
  };

  Model.prototype.init = function(modelManager) {
    var self = this;

    this.modelManager =
    this.daoFactoryManager = modelManager;
    this.primaryKeys = {};
    self.options.uniqueKeys = {};

    // Setup names of timestamp attributes
    this._timestampAttributes = {};
    if (this.options.timestamps) {
      if (this.options.createdAt) {
        this._timestampAttributes.createdAt = Utils._.underscoredIf(this.options.createdAt, this.options.underscored);
      }
      if (this.options.updatedAt) {
        this._timestampAttributes.updatedAt = Utils._.underscoredIf(this.options.updatedAt, this.options.underscored);
      }
      if (this.options.paranoid && this.options.deletedAt) {
        this._timestampAttributes.deletedAt = Utils._.underscoredIf(this.options.deletedAt, this.options.underscored);
      }
    }

    // Identify primary and unique attributes
    Utils._.each(this.rawAttributes, function(options, attribute) {
      if (options.hasOwnProperty('unique')) {
        var idxName;
        if (options.unique === true) {
          idxName = self.tableName + '_' + attribute + '_unique';
          self.options.uniqueKeys[idxName] = {
            name: idxName,
            fields: [attribute],
            singleField: true
          };
        } else if (options.unique !== false) {
          idxName = options.unique;
          if (typeof options.unique === 'object') {
            idxName = options.unique.name;
          }

          self.options.uniqueKeys[idxName] = self.options.uniqueKeys[idxName] || {fields: [], msg: null};
          self.options.uniqueKeys[idxName].fields.push(options.field || attribute);
          self.options.uniqueKeys[idxName].msg = self.options.uniqueKeys[idxName].msg || options.unique.msg || null;
          self.options.uniqueKeys[idxName].name = idxName || false;
        }

      }

      if (options.primaryKey === true) {
        self.primaryKeys[attribute] = self.attributes[attribute];
      }
    });

    // Add head and tail default attributes (id, timestamps)
    addDefaultAttributes.call(this);
    addOptionalClassMethods.call(this);
    // Primary key convenience variables
    this.primaryKeyAttributes = Object.keys(this.primaryKeys);
    this.primaryKeyAttribute = this.primaryKeyAttributes[0];
    this.primaryKeyField = this.rawAttributes[this.primaryKeyAttribute].field || this.primaryKeyAttribute;

    this.primaryKeyCount = this.primaryKeyAttributes.length;
    this._hasPrimaryKeys = this.options.hasPrimaryKeys = this.hasPrimaryKeys = this.primaryKeyCount > 0;

    this._isPrimaryKey = Utils._.memoize(function(key) {
      return self.primaryKeyAttributes.indexOf(key) !== -1;
    });


    if (typeof this.options.defaultScope === 'object') {
      Utils.injectScope.call(this, this.options.defaultScope);
    }

    // Instance prototype
    this.Instance = this.DAO = function() {
      Instance.apply(this, arguments);
    };

    Util.inherits(this.Instance, Instance);

    this._readOnlyAttributes = Utils._.values(this._timestampAttributes);
    this._hasReadOnlyAttributes = this._readOnlyAttributes && this._readOnlyAttributes.length;
    this._isReadOnlyAttribute = Utils._.memoize(function(key) {
      return self._hasReadOnlyAttributes && self._readOnlyAttributes.indexOf(key) !== -1;
    });

    if (this.options.instanceMethods) {
      Utils._.each(this.options.instanceMethods, function(fct, name) {
        self.Instance.prototype[name] = fct;
      });
    }
    this.refreshAttributes();
    findAutoIncrementField.call(this);

    this.Instance.prototype.$Model =
    this.Instance.prototype.Model = this;

    return this;
  };

  Model.prototype.refreshAttributes = function() {
    var self = this
      , attributeManipulation = {};

    this.Instance.prototype._customGetters = {};
    this.Instance.prototype._customSetters = {};

    Utils._.each(['get', 'set'], function(type) {
      var opt = type + 'terMethods'
        , funcs = Utils._.clone(Utils._.isObject(self.options[opt]) ? self.options[opt] : {})
        , _custom = type === 'get' ? self.Instance.prototype._customGetters : self.Instance.prototype._customSetters;

      Utils._.each(funcs, function(method, attribute) {
        _custom[attribute] = method;

        if (type === 'get') {
          funcs[attribute] = function() {
            return this.get(attribute);
          };
        }
        if (type === 'set') {
          funcs[attribute] = function(value) {
            return this.set(attribute, value);
          };
        }
      });

      Utils._.each(self.rawAttributes, function(options, attribute) {
        if (options.hasOwnProperty(type)) {
          _custom[attribute] = options[type];
        }

        if (type === 'get') {
          funcs[attribute] = function() {
            return this.get(attribute);
          };
        }
        if (type === 'set') {
          funcs[attribute] = function(value) {
            return this.set(attribute, value);
          };
        }
      });

      Utils._.each(funcs, function(fct, name) {
        if (!attributeManipulation[name]) {
          attributeManipulation[name] = {
            configurable: true
          };
        }
        attributeManipulation[name][type] = fct;
      });
    });

    this._booleanAttributes = [];
    this._dateAttributes = [];
    this._hstoreAttributes = [];
    this._rangeAttributes = [];
    this._jsonAttributes = [];
    this._virtualAttributes = [];
    this._defaultValues = {};
    this.Instance.prototype.validators = {};

    Utils._.each(this.rawAttributes, function(definition, name) {
      definition.type = self.sequelize.normalizeDataType(definition.type);

      definition.Model = self;
      definition.fieldName = name;
      definition._modelAttribute = true;

      if (definition.field === undefined) {
        definition.field = name;
      }

      if (definition.type instanceof DataTypes.BOOLEAN) {
        self._booleanAttributes.push(name);
      } else if (definition.type instanceof DataTypes.DATE) {
        self._dateAttributes.push(name);
      } else if (definition.type instanceof DataTypes.HSTORE || DataTypes.ARRAY.is(definition.type, DataTypes.HSTORE)) {
        self._hstoreAttributes.push(name);
      } else if (definition.type instanceof DataTypes.RANGE || DataTypes.ARRAY.is(definition.type, DataTypes.RANGE)) {
        self._rangeAttributes.push(name);
      } else if (definition.type instanceof DataTypes.JSON) {
        self._jsonAttributes.push(name);
      } else if (definition.type instanceof DataTypes.VIRTUAL) {
        self._virtualAttributes.push(name);
      }

      if (definition.hasOwnProperty('defaultValue')) {
        if (typeof definition.defaultValue === "function" && (
            definition.defaultValue === DataTypes.NOW ||
            definition.defaultValue === DataTypes.UUIDV4 ||
            definition.defaultValue === DataTypes.UUIDV4
        )) {
          definition.defaultValue = new definition.defaultValue();
        }

        self._defaultValues[name] = Utils._.partial(Utils.toDefaultValue, definition.defaultValue);
      }

      if (definition.hasOwnProperty('validate')) {
        self.Instance.prototype.validators[name] = definition.validate;
      }
    });

    this._hasBooleanAttributes = !!this._booleanAttributes.length;
    this._isBooleanAttribute = Utils._.memoize(function(key) {
      return self._booleanAttributes.indexOf(key) !== -1;
    });

    this._hasDateAttributes = !!this._dateAttributes.length;
    this._isDateAttribute = Utils._.memoize(function(key) {
      return self._dateAttributes.indexOf(key) !== -1;
    });

    this._hasHstoreAttributes = !!this._hstoreAttributes.length;
    this._isHstoreAttribute = Utils._.memoize(function(key) {
      return self._hstoreAttributes.indexOf(key) !== -1;
    });

    this._hasRangeAttributes = !!this._rangeAttributes.length;
    this._isRangeAttribute = Utils._.memoize(function(key) {
      return self._rangeAttributes.indexOf(key) !== -1;
    });

    this._hasJsonAttributes = !!this._jsonAttributes.length;
    this._isJsonAttribute = Utils._.memoize(function(key) {
      return self._jsonAttributes.indexOf(key) !== -1;
    });

    this._hasVirtualAttributes = !!this._virtualAttributes.length;
    this._isVirtualAttribute = Utils._.memoize(function(key) {
      return self._virtualAttributes.indexOf(key) !== -1;
    });

    this._hasDefaultValues = !Utils._.isEmpty(this._defaultValues);

    this.attributes = this.rawAttributes;
    this.tableAttributes = Utils._.omit(this.rawAttributes, this._virtualAttributes);

    this.Instance.prototype._hasCustomGetters = Object.keys(this.Instance.prototype._customGetters).length;
    this.Instance.prototype._hasCustomSetters = Object.keys(this.Instance.prototype._customSetters).length;

    Object.defineProperties(this.Instance.prototype, attributeManipulation);

    this.Instance.prototype.rawAttributes = this.rawAttributes;
    this.Instance.prototype.attributes = Object.keys(this.Instance.prototype.rawAttributes);
    this.Instance.prototype._isAttribute = Utils._.memoize(function(key) {
      return self.Instance.prototype.attributes.indexOf(key) !== -1;
    });
  };

  /**
   * Remove attribute from model definition
   * @param {String} [attribute]
   */
  Model.prototype.removeAttribute = function(attribute) {
    delete this.rawAttributes[attribute];
    this.refreshAttributes();
  };

  /**
   * Sync this Model to the DB, that is create the table. Upon success, the callback will be called with the model instance (this)
   * @see {Sequelize#sync} for options
   * @return {Promise<this>}
   */
  Model.prototype.sync = function(options) {
    options = Utils._.extend({}, this.options, options || {});

    var self = this
      , attributes = this.tableAttributes;

    return Promise.resolve().then(function () {
      if (options.force) {
        return self.drop(options);
      }
    }).then(function () {
      return self.QueryInterface.createTable(self.getTableName(options), attributes, options);
    }).then(function () {
      return self.QueryInterface.showIndex(self.getTableName(options), options);
    }).then(function (indexes) {
      // Assign an auto-generated name to indexes which are not named by the user
      self.options.indexes = self.QueryInterface.nameIndexes(self.options.indexes, self.tableName);

      indexes = Utils._.filter(self.options.indexes, function (item1) {
        return !Utils._.any(indexes, function (item2) {
          return item1.name === item2.name;
        });
      });

      return Promise.map(indexes, function (index) {
        return self.QueryInterface.addIndex(self.getTableName(options), index.fields, index, self.tableName);
      });
    }).return(this);
  };

  /**
   * Drop the table represented by this Model
   * @param {Object}  [options]
   * @param {Boolean} [options.cascade=false] Also drop all objects depending on this table, such as views. Only works in postgres
   * @return {Promise}
   */
  Model.prototype.drop = function(options) {
    return this.QueryInterface.dropTable(this.getTableName(options), options);
  };

  Model.prototype.dropSchema = function(schema) {
    return this.QueryInterface.dropSchema(schema);
  };

  /**
   * Apply a schema to this model. For postgres, this will actually place the schema in front of the table name - `"schema"."tableName"`,
   * while the schema will be prepended to the table name for mysql and sqlite - `'schema.tablename'`.
   *
   * @param {String} schema The name of the schema
   * @param {Object} [options]
   * @param {String} [options.schemaDelimiter='.'] The character(s) that separates the schema name from the table name
   * @return this
   */
  Model.prototype.schema = function(schema, options) {
    this.options.schema = schema;

    if (!!options) {
      if (typeof options === 'string') {
        this.options.schemaDelimiter = options;
      } else {
        if (!!options.schemaDelimiter) {
          this.options.schemaDelimiter = options.schemaDelimiter;
        }
      }
    }

    return this;
  };

  /**
   * Get the tablename of the model, taking schema into account. The method will return The name as a string if the model has no schema,
   * or an object with `tableName`, `schema` and `delimiter` properties.
   *
   * @param {Object}  options  The hash of options from any query. You can use one model to access tables with matching schemas by overriding `getTableName` and using custom key/values to alter the name of the table. (eg. subscribers_1, subscribers_2)
   * @return {String|Object}
   */
  Model.prototype.getTableName = function(options) {
    return this.QueryGenerator.addSchema(this);
  };

  /**
   * Apply a scope created in `define` to the model. First let's look at how to create scopes:
   * ```js
   * var Model = sequelize.define('model', attributes, {
   *   defaultScope: {
   *     where: {
   *       username: 'dan'
   *     },
   *     limit: 12
   *   },
   *   scopes: {
   *     isALie: {
   *       where: {
   *         stuff: 'cake'
   *       }
   *     },
   *     complexFunction: function(email, accessLevel) {
   *       return {
   *         where: ['email like ? AND access_level >= ?', email + '%', accessLevel]
   *       }
   *     },
   *   }
   * })
   * ```
   * Now, since you defined a default scope, every time you do Model.find, the default scope is appended to your query. Here's a couple of examples:
   * ```js
   * Model.findAll() // WHERE username = 'dan'
   * Model.findAll({ where: { age: { gt: 12 } } }) // WHERE age > 12 AND username = 'dan'
   * ```
   *
   * To invoke scope functions you can do:
   * ```js
   * Model.scope({ method: ['complexFunction' 'dan@sequelize.com', 42]}).findAll()
   * // WHERE email like 'dan@sequelize.com%' AND access_level >= 42
   * ```
   *
   * @param {Array|Object|String|null}    options* The scope(s) to apply. Scopes can either be passed as consecutive arguments, or as an array of arguments. To apply simple scopes, pass them as strings. For scope function, pass an object, with a `method` property. The value can either be a string, if the method does not take any arguments, or an array, where the first element is the name of the method, and consecutive elements are arguments to that method. Pass null to remove all scopes, including the default.
   * @return {Model}                      A reference to the model, with the scope(s) applied. Calling scope again on the returned model will clear the previous scope.
   */
  Model.prototype.scope = function(option) {
    var self = Object.create(this)
      , type
      , options
      , merge
      , i
      , scope
      , scopeName
      , scopeOptions
      , argLength = arguments.length
      , lastArg = arguments[argLength - 1];

    self.scoped = true;

    // Set defaults
    scopeOptions = (typeof lastArg === 'object' && !Array.isArray(lastArg) ? lastArg : {}) || {}; // <-- for no arguments
    scopeOptions.silent = (scopeOptions !== null && scopeOptions.hasOwnProperty('silent') ? scopeOptions.silent : true);

    // Clear out any predefined scopes...
    self.scopeObj = {};

    // Possible formats for option:
    // String of arguments: 'hello', 'world', 'etc'
    // Array: ['hello', 'world', 'etc']
    // Object: {merge: 'hello'}, {method: ['scopeName' [, args1, args2..]]}, {merge: true, method: ...}

    if (argLength < 1 || !option) {
      return self;
    }

    for (i = 0; i < argLength; i++) {
      options = Array.isArray(arguments[i]) ? arguments[i] : [arguments[i]];

      options.forEach(function(o) {
        type = typeof o;
        scope = null;
        merge = false;
        scopeName = null;

        if (type === 'object') {
          // Right now we only support a merge functionality for objects
          if (!!o.merge) {
            merge = true;
            scopeName = o.merge[0];
            if (Array.isArray(o.merge) && !!self.options.scopes[scopeName]) {
              scope = self.options.scopes[scopeName].apply(self, o.merge.splice(1));
            }
            else if (typeof o.merge === 'string') {
              scopeName = o.merge;
              scope = self.options.scopes[scopeName];
            }
          }

          if (!!o.method) {
            if (Array.isArray(o.method) && !!self.options.scopes[o.method[0]]) {
              scopeName = o.method[0];
              scope = self.options.scopes[scopeName].apply(self, o.method.splice(1));
              merge = !!o.merge;
            }
            else if (!!self.options.scopes[o.method]) {
              scopeName = o.method;
              scope = self.options.scopes[scopeName].apply(self);
            }
          } else {
            scopeName = o;
            scope = self.options.scopes[scopeName];
          }

          if (o.where) {
            scope = o;
            merge = true;
          }
        } else {
          scopeName = o;
          scope = self.options.scopes[scopeName];
        }

        if (!!scope) {
          Utils.injectScope.call(self, scope, merge);
        }
        else if (scopeOptions.silent !== true && !!scopeName) {
          throw new Error('Invalid scope ' + scopeName + ' called.');
        }
      });
    }

    return self;
  };

  Model.prototype.all = function(options, queryOptions) {
    return this.findAll(options, queryOptions);
  };

  /**
   * Search for multiple instances.
   *
   * __Simple search using AND and =__
   * ```js
   * Model.findAll({
   *   where: {
   *     attr1: 42,
   *     attr2: 'cake'
   *   }
   * })
   * ```
   * ```sql
   * WHERE attr1 = 42 AND attr2 = 'cake'
   *```
   *
   * __Using greater than, less than etc.__
   * ```js
   *
   * Model.findAll({
   *   where: {
   *     attr1: {
   *       gt: 50
   *     },
   *     attr2: {
   *       lte: 45
   *     },
   *     attr3: {
   *       in: [1,2,3]
   *     },
   *     attr4: {
   *       ne: 5
   *     }
   *   }
   * })
   * ```
   * ```sql
   * WHERE attr1 > 50 AND attr2 <= 45 AND attr3 IN (1,2,3) AND attr4 != 5
   * ```
   * Possible options are: `gt, gte, lt, lte, ne, between/.., nbetween/notbetween/!.., in, not, like, nlike/notlike`
   *
   * __Queries using OR__
   * ```js
   * Model.findAll({
   *   where: Sequelize.and(
   *     { name: 'a project' },
   *     Sequelize.or(
   *       { id: [1,2,3] },
   *       { id: { gt: 10 } }
   *     )
   *   )
   * })
   * ```
   * ```sql
   * WHERE name = 'a project' AND (id` IN (1,2,3) OR id > 10)
   * ```
   *
   * The success listener is called with an array of instances if the query succeeds.
   *
   * @param  {Object}                    [options] A hash of options to describe the scope of the search
   * @param  {Object}                    [options.where] A hash of attributes to describe your search. See above for examples.
   * @param  {Array<String>}             [options.attributes] A list of the attributes that you want to select. To rename an attribute, you can pass an array, with two elements - the first is the name of the attribute in the DB (or some kind of expression such as `Sequelize.literal`, `Sequelize.fn` and so on), and the second is the name you want the attribute to have in the returned instance
   * @param  {Boolean}                   [options.paranoid=true] If true, only non-deleted records will be returned. If false, both deleted and non-deleted records will be returned. Only applies if `options.paranoid` is true for the model.
   * @param  {Array<Object|Model>}       [options.include] A list of associations to eagerly load using a left join. Supported is either `{ include: [ Model1, Model2, ...]}` or `{ include: [{ model: Model1, as: 'Alias' }]}`. If your association are set up with an `as` (eg. `X.hasMany(Y, { as: 'Z }`, you need to specify Z in the as attribute when eager loading Y).
   * @param  {Model}                     [options.include[].model] The model you want to eagerly load
   * @param  {String}                    [options.include[].as] The alias of the relation, in case the model you want to eagerly load is aliassed. For `hasOne` / `belongsTo`, this should be the singular name, and for `hasMany`, it should be the plural
   * @param  {Association}               [options.include[].association] The association you want to eagerly load. (This can be used instead of providing a model/as pair)
   * @param  {Object}                    [options.include[].where] Where clauses to apply to the child models. Note that this converts the eager load to an inner join, unless you explicitly set `required: false`
   * @param  {Array<String>}             [options.include[].attributes] A list of attributes to select from the child model
   * @param  {Boolean}                   [options.include[].required] If true, converts to an inner join, which means that the parent model will only be loaded if it has any matching children. True if `include.where` is set, false otherwise.
   * @param  {Array<Object|Model>}       [options.include[].include] Load further nested related models
   * @param  {String|Array|Sequelize.fn} [options.order] Specifies an ordering. If a string is provided, it will be esacped. Using an array, you can provide several columns / functions to order by. Each element can be further wrapped in a two-element array. The first element is the column / function to order by, the second is the direction. For example: `order: [['name', 'DESC']]`. In this way the column will be escaped, but the direction will not.
   * @param  {Number}                    [options.limit]
   * @param  {Number}                    [options.offset]
   * @param  {Transaction}               [options.transaction]
   * @param  {Object}                    [queryOptions] Set the query options, e.g. raw, specifying that you want raw data instead of built Instances. See sequelize.query for options
   * @param  {String}                    [queryOptions.lock] Lock the selected rows in either share or update mode. Possible options are transaction.LOCK.UPDATE and transaction.LOCK.SHARE. See [transaction.LOCK for an example](https://github.com/sequelize/sequelize/wiki/API-Reference-Transaction#LOCK)
   *
   * @see    {Sequelize#query}
   * @return {Promise<Array<Instance>>}
   * @alias all
   */
  Model.prototype.findAll = function(options, queryOptions) {
    var hasJoin = false
      , tableNames = { };

    tableNames[this.getTableName(options)] = true;
    options = optClone(options || {});
    options = Utils._.defaults(options, {
      hooks: true
    });

    return Promise.bind(this).then(function() {
      conformOptions(options);

      if (options.hooks) {
        return this.runHooks('beforeFind', options);
      }
    }).then(function() {
      expandIncludeAll.call(this, options);

      if (options.hooks) {
        return this.runHooks('beforeFindAfterExpandIncludeAll', options);
      }
    }).then(function() {
      if (typeof options === 'object') {
        if (options.include) {
          hasJoin = true;

          validateIncludedElements.call(this, options, tableNames);

          if (options.attributes) {
            if (options.attributes.indexOf(this.primaryKeyAttribute) === -1) {
              options.originalAttributes = options.attributes;
              options.attributes = [this.primaryKeyAttribute].concat(options.attributes);
            }
          }
        }

        // whereCollection is used for non-primary key updates
        this.options.whereCollection = options.where || null;
      }

      if (options.attributes === undefined) {
        options.attributes = Object.keys(this.tableAttributes);
      }
      Utils.mapOptionFieldNames(options, this);

      options = paranoidClause(this, options);

      if (options.hooks) {
        return this.runHooks('beforeFindAfterOptions', options);
      }
    }).then(function() {
      return this.QueryInterface.select(this, this.getTableName(options), options, Utils._.defaults({
        hasJoin: hasJoin,
        tableNames: Object.keys(tableNames)
      }, queryOptions, { transaction: options.transaction, logging: options.logging }));
    }).tap(function(results) {
      if (options.hooks) {
        return this.runHooks('afterFind', results, options);
      }
    });
  };

  //right now, the caller (has-many-double-linked) is in charge of the where clause
  Model.prototype.findAllJoin = function(joinTableName, options, queryOptions) {
    options = optClone(options || {});
    options.attributes = options.attributes || [this.QueryInterface.quoteTable(this.name) + '.*'];
    // whereCollection is used for non-primary key updates
    this.options.whereCollection = options.where || null;

    return this.QueryInterface.select(this, [[this.getTableName(options), this.name], joinTableName], options, Utils._.defaults(queryOptions, { transaction: (options || {}).transaction }));
  };

 /**
  * Search for a single instance. This applies LIMIT 1, so the listener will always be called with a single instance.
  *
  * @param  {Object|Number}             [options] A hash of options to describe the scope of the search, or a number to search by id.
  * @param  {Transaction}               [options.transaction]
  * @param  {Object}                    [queryOptions]
  *
  * @see {Model#findAll}           for an explanation of options and queryOptions
  * @return {Promise<Instance>}
  * @alias find
  */
  Model.prototype.findOne = function(param, queryOptions) {
    // For sanity findOne will never return if no options are passed
    if ([null, undefined].indexOf(param) !== -1) {
      return Promise.resolve(null);
    }

    var options = {};
    if (typeof param === 'number' || typeof param === 'string' || Buffer.isBuffer(param)) {
      options.where = {};
      options.where[this.primaryKeyAttribute] = param;
    } else {
      options = optClone(param);
    }

    if (options.limit === undefined && !(options.where && options.where[this.primaryKeyAttribute])) {
      options.limit = 1;
    }

    // Bypass a possible overloaded findAll.
    return Model.prototype.findAll.call(this, options, Utils._.defaults({
      plain: true
    }, queryOptions || {}));
  };
  Model.prototype.find = Model.prototype.findOne;

  /**
   * Run an aggregation method on the specified field
   *
   * @param {String}          field The field to aggregate over. Can be a field name or *
   * @param {String}          aggregateFunction The function to use for aggregation, e.g. sum, max etc.
   * @param {Object}          [options] Query options. See sequelize.query for full options
   * @param {Object}          [options.where] A hash of search attributes.
   * @param {DataType|String} [options.dataType] The type of the result. If `field` is a field in this Model, the default will be the type of that field, otherwise defaults to float.
   * @param {boolean}         [options.distinct] Applies DISTINCT to the field being aggregated over
   * @param {Transaction}     [options.transaction]
   * @param {boolean}         [options.plain] When `true`, the first returned value of `aggregateFunction` is cast to `dataType` and returned. If additional attributes are specified, along with `group` clauses, set `plain` to `false` to return all values of all returned rows.  Defaults to `true`
   *
   * @return {Promise<options.dataType|object>}                Returns the aggregate result cast to `options.dataType`, unless `options.plain` is false, in which case the complete data result is returned.
   */
  Model.prototype.aggregate = function(field, aggregateFunction, options) {
    options = Utils._.extend({ attributes: [] }, options || {});

    var aggregateColumn = this.sequelize.col(field);
    if (options.distinct) {
      aggregateColumn = this.sequelize.fn('DISTINCT', aggregateColumn);
    }
    options.attributes.push([this.sequelize.fn(aggregateFunction, aggregateColumn), aggregateFunction]);

    if (!options.dataType) {
      if (this.rawAttributes[field]) {
        options.dataType = this.rawAttributes[field].type;
      } else {
        // Use FLOAT as fallback
        options.dataType = new DataTypes.FLOAT();
      }
    } else {
      options.dataType = this.sequelize.normalizeDataType(options.dataType);
    }

    options = paranoidClause(this, options);

    return this.QueryInterface.rawSelect(this.getTableName(options), options, aggregateFunction, this);
  };

  /**
   * Count the number of records matching the provided where clause.
   *
   * If you provide an `include` option, the number of matching associations will be counted instead.
   *
   * @param {Object}  [options]
   * @param {Object}  [options.where] A hash of search attributes.
   * @param {Object}  [options.include] Include options. See `find` for details
   * @param {boolean} [options.distinct] Apply COUNT(DISTINCT(col))
   * @param {Object}  [options.attributes] Used in conjustion with `group`
   * @param {Object}  [options.group] For creating complex counts. Will return multiple rows as needed.
   *
   * @return {Promise<Integer>}
   */
  Model.prototype.count = function(options) {
    options = Utils._.clone(options || {});
    conformOptions(options);

    var col = '*';
    if (options.include) {
      col = this.name + '.' + this.primaryKeyAttribute;
      expandIncludeAll.call(this, options);
      validateIncludedElements.call(this, options);
    }

    Utils.mapOptionFieldNames(options, this);

    options.plain = options.group ? false : true;
    options.dataType = new DataTypes.INTEGER();
    options.includeIgnoreAttributes = false;
    options.limit = null;

    return this.aggregate(col, 'count', options);
  };

  /**
   * Find all the rows matching your query, within a specified offset / limit, and get the total number of rows matching your query. This is very usefull for paging
   *
   * ```js
   * Model.findAndCountAll({
   *   where: ...,
   *   limit: 12,
   *   offset: 12
   * }).success(function (result) {
   * })
   * ```
   * In the above example, `result.rows` will contain rows 13 through 24, while `result.count` will return the total number of rows that matched your query.
   *
   * @param {Object} [findOptions] See findAll
   * @param {Object} [queryOptions] See Sequelize.query
   *
   * @see {Model#findAll} for a specification of find and query options
   * @return {Promise<Object>}
   * @alias findAndCountAll
   */
  Model.prototype.findAndCount = function(findOptions, queryOptions) {
    findOptions = findOptions || {};

    var self = this
      // no limit, offset, order, attributes for the options given to count()
      , countOptions = _.omit(_.clone(findOptions), ['offset', 'limit', 'order', 'attributes']);

    conformOptions(countOptions);
    if (countOptions.include) {
      countOptions.include = _.cloneDeep(countOptions.include, function (element) {
        if (element instanceof Model) return element;
        if (element instanceof Association) return element;
        return undefined;
      });

      expandIncludeAll.call(this, countOptions);

      validateIncludedElements.call(this, countOptions);

      var keepNeeded = function(includes) {
        return includes.filter(function (include) {
          if (include.include) include.include = keepNeeded(include.include);

          return include.required || include.hasIncludeRequired;
        });
      };
      countOptions.include = keepNeeded(countOptions.include);
    }

    return self.count(countOptions).then(function(count) {
      if (count === 0) {
        return {
          count: count || 0,
          rows: []
        };
      }
      return self.findAll(findOptions, queryOptions).then(function(results) {
        return {
          count: count || 0,
          rows: (results && Array.isArray(results) ? results : [])
        };
      });
    });
  };
  Model.prototype.findAndCountAll = Model.prototype.findAndCount;


  /**
   * Find the maximum value of field
   *
   * @param {String} field
   * @param {Object} [options] See aggregate
   * @see {Model#aggregate} for options
   *
   * @return {Promise<Any>}
   */
  Model.prototype.max = function(field, options) {
    return this.aggregate(field, 'max', options);
  };

  /**
   * Find the minimum value of field
   *
   * @param {String} field
   * @param {Object} [options] See aggregate
   * @see {Model#aggregate} for options
   *
   * @return {Promise<Any>}
   */
  Model.prototype.min = function(field, options) {
    return this.aggregate(field, 'min', options);
  };

  /**
   * Find the sum of field
   *
   * @param {String} field
   * @param {Object} [options] See aggregate
   * @see {Model#aggregate} for options
   *
   * @return {Promise<Number>}
   */
  Model.prototype.sum = function(field, options) {
    return this.aggregate(field, 'sum', options);
  };

  /**
   * Builds a new model instance. Values is an object of key value pairs, must be defined but can be empty.

   * @param {Object}  values
   * @param {Object}  [options]
   * @param {Boolean} [options.raw=false] If set to true, values will ignore field and virtual setters.
   * @param {Boolean} [options.isNewRecord=true]
   * @param {Boolean} [options.isDirty=true]
   * @param {Array}   [options.include] an array of include options - Used to build prefetched/included model instances. See `set`
   *
   * @return {Instance}
   */
  Model.prototype.build = function(values, options) {
    if (Array.isArray(values)) {
      return this.bulkBuild(values, options);
    }
    options = Utils._.extend({
      isNewRecord: true,
      isDirty: true
    }, options || {});

    if (options.attributes) {
      options.attributes = options.attributes.map(function(attribute) {
        return Array.isArray(attribute) ? attribute[1] : attribute;
      });
    }

    if (!options.includeValidated) {
      conformOptions(options);
      if (options.include) {
        expandIncludeAll.call(this, options);
        validateIncludedElements.call(this, options);
      }
    }

    return new this.Instance(values, options);
  };


  Model.prototype.bulkBuild = function(valueSets, options) {
    options = Utils._.extend({
      isNewRecord: true,
      isDirty: true
    }, options || {});

    if (!options.includeValidated) {
      conformOptions(options);
      if (options.include) {
        expandIncludeAll.call(this, options);
        validateIncludedElements.call(this, options);
      }
    }

    if (options.attributes) {
      options.attributes = options.attributes.map(function(attribute) {
        return Array.isArray(attribute) ? attribute[1] : attribute;
      });
    }

    return valueSets.map(function(values) {
      return this.build(values, options);
    }.bind(this));
  };

  /**
   * Builds a new model instance and calls save on it.

   * @see {Instance#build}
   * @see {Instance#save}
   *
   * @param {Object}        values
   * @param {Object}        [options]
   * @param {Boolean}       [options.raw=false] If set to true, values will ignore field and virtual setters.
   * @param {Boolean}       [options.isNewRecord=true]
   * @param {Boolean}       [options.isDirty=true]
   * @param {Array}         [options.fields] If set, only columns matching those in fields will be saved
   * @param {Array}         [options.include] an array of include options - Used to build prefetched/included model instances
   * @param {String}        [options.onDuplicate]
   * @param {Transaction}   [options.transaction]
   *
   * @return {Promise<Instance>}
   */
  Model.prototype.create = function(values, options) {
    Utils.validateParameter(values, Object, { optional: true });
    Utils.validateParameter(options, Object, { deprecated: Array, optional: true, index: 2, method: 'Model#create' });
    if (options instanceof Array) {
      options = { fields: options };
    }

    options = options || {};

    return this.build(values, {
      isNewRecord: true,
      attributes: options.fields,
      include: options.include,
      raw: options.raw,
      silent: options.silent
    }).save(options);
  };

  /**
   * Find a row that matches the query, or build (but don't save) the row if none is found.
   * The successfull result of the promise will be (instance, initialized) - Make sure to use .spread()
   *
   * @param {Object}  options
   * @param {Object}  options.where A hash of search attributes.
   * @param {Object}  [options.defaults] Default values to use if building a new instance
   * @param {Object}  [options.transaction] Transaction to run query under
   *
   * @return {Promise<Instance>}
   * @alias findOrBuild
   */
  Model.prototype.findOrInitialize = Model.prototype.findOrBuild = function(options) {
    if (!options || !options.where) {
      throw new Error('Missing where attribute in the options parameter passed to findOrCreate. Please note that the API has changed, and is now options (an object with where and defaults keys), queryOptions (transaction etc.)');
    }

    var self = this
      , values;

    return self.find({
      where: options.where
    }, options).then(function(instance) {
      if (instance === null) {
        values = Utils._.clone(options.defaults) || {};
        if (Utils._.isPlainObject(options.where)) {
          values = Utils._.defaults(values, options.where);
        }

        instance = self.build(values);

        return Promise.resolve([instance, true]);
      }

      return Promise.resolve([instance, false]);
    });
  };

  /**
   * Find a row that matches the query, or build and save the row if none is found
   * The successfull result of the promise will be (instance, created) - Make sure to use .spread()
   *
   * If no transaction is passed in the `queryOptions` object, a new transaction will be created internally, to prevent the race condition where a matching row is created by another connection after the find but before the insert call.
   * However, it is not always possible to handle this case in SQLite, specifically if one transaction inserts and another tries to select before the first one has comitted. In this case, an instance of sequelize.TimeoutError will be thrown instead.
   * If a transaction is created, a savepoint will be created instead, and any unique constraint violation will be handled internally.
   *
   * @param {Object}  options
   * @param {Object}  options.where where A hash of search attributes.
   * @param {Object}  [options.defaults] Default values to use if creating a new instance
   * @param {Object}  [queryOptions] Options passed to the find and create calls
   *
   * @return {Promise<Instance,created>}
   */
  Model.prototype.findOrCreate = function(options, queryOptions) {
    var self = this
      , internalTransaction = !(queryOptions && queryOptions.transaction)
      , values
      , whereFields
      , defaultFields;

    if (!options || !options.where) {
      throw new Error('Missing where attribute in the options parameter passed to findOrCreate. Please note that the API has changed, and is now options (an object with where and defaults keys), queryOptions (transaction etc.)');
    }

    queryOptions = queryOptions ? Utils._.clone(queryOptions) : {};
    if (options.logging) queryOptions.logging = options.logging;

    whereFields = Object.keys(options.where);
    if (options.defaults) defaultFields = Object.keys(options.defaults);

    // Create a transaction or a savepoint, depending on whether a transaction was passed in
    return self.sequelize.transaction(queryOptions).bind({}).then(function (transaction) {
      this.transaction = transaction;
      queryOptions.transaction = transaction;

      return self.find(options, {
        transaction: transaction
      });
    }).then(function(instance) {
      if (instance !== null) {
        return [instance, false];
      }

      values = Utils._.clone(options.defaults) || {};
      if (Utils._.isPlainObject(options.where)) {
        values = Utils._.defaults(values, options.where);
      }

      queryOptions.exception = true;

      return self.create(values, queryOptions).bind(this).then(function(instance) {
        if (instance.get(self.primaryKeyAttribute, { raw: true }) === null) {
          // If the query returned an empty result for the primary key, we know that this was actually a unique constraint violation
          throw new self.sequelize.UniqueConstraintError();
        }

        return [instance, true];
      }).catch(self.sequelize.UniqueConstraintError, function (err) {
        if (defaultFields) {
          if (!_.intersection(err.fields, whereFields).length && _.intersection(err.fields, defaultFields).length) {
            throw err;
          }
        }

        // Someone must have created a matching instance inside the same transaction since we last did a find. Let's find it!
        return self.find(options, {
          transaction: internalTransaction ? null : this.transaction
        }).then(function(instance) {
          // Sanity check, ideally we caught this at the defaultFeilds/err.fields check
          // But if we didn't and instance is null, we will throw
          if (instance === null) throw err;
          return [instance, false];
        });
      });
    }).finally(function () {
      if (internalTransaction && this.transaction) {
        // If we created a transaction internally, we should clean it up
        return this.transaction.commit();
      }
    });
  };

  /**
   * Insert or update a single row. An update will be executed if a row which matches the supplied values on either the primary key or a unique key is found. Note that the unique index must be defined in your sequelize model and not just in the table. Otherwise you may experience a unique constraint violation, because sequelize fails to identify the row that should be updated.
   *
   * **Implementation details:**
   *
   * * MySQL - Implemented as a single query `INSERT values ON DUPLICATE KEY UPDATE values`
   * * PostgreSQL - Implemented as a temporary function with exception handling: INSERT EXCEPTION WHEN unique_constraint UPDATE
   * * SQLite - Implemented as two queries `INSERT; UPDATE`. This means that the update is executed regardless of whether the row already existed or not
   *
   * **Note** that SQLite returns undefined for created, no matter if the row was created or updated. This is because SQLite always runs INSERT OR IGNORE + UPDATE, in a single query, so there is no way to know whether the row was inserted or not.
   *
   * @param  {Object}   values
   * @param  {Object}   [options]
   * @param  {Boolean}  [options.validate=true] Run validations before the row is inserted
   * @param  {Array}    [options.fields=Object.keys(this.attributes)] The fields to insert / update. Defaults to all fields
   *
   * @alias insertOrUpdate
   * @return {Promise<created>} Returns a boolean indicating whether the row was created or updated.
   */
  Model.prototype.upsert = function (values, options) {
    options = options || {};

    if (!options.fields) {
      options.fields = Object.keys(this.attributes);
    }

    var createdAtAttr = this._timestampAttributes.createdAt
      , updatedAtAttr = this._timestampAttributes.updatedAt
      , hadPrimary = this.primaryKeyField in values
      , instance = this.build(values);

    return instance.hookValidate(options).bind(this).then(function () {
      // Map field names
      values = Utils.mapValueFieldNames(instance.dataValues, options.fields, this);

      if (createdAtAttr && !values[createdAtAttr]) {
        values[createdAtAttr] = this.__getTimestamp(createdAtAttr);
      }
      if (updatedAtAttr && !values[updatedAtAttr]) {
        values[updatedAtAttr] = this.__getTimestamp(updatedAtAttr);
      }

      // Build adds a null value for the primary key, if none was given by the user.
      // We need to remove that because of some Postgres technicalities.
      if (!hadPrimary) {
        delete values[this.primaryKeyField];
      }

      return this.QueryInterface.upsert(this.getTableName(options), values, this, options);
    });
  };

  Model.prototype.insertOrUpdate = Model.prototype.upsert;

  /**
   * Create and insert multiple instances in bulk.
   *
   * The success handler is passed an array of instances, but please notice that these may not completely represent the state of the rows in the DB. This is because MySQL
   * and SQLite do not make it easy to obtain back automatically generated IDs and other default values in a way that can be mapped to multiple records.
   * To obtain Instances for the newly created values, you will need to query for them again.
   *
   * @param  {Array}        records                          List of objects (key/value pairs) to create instances from
   * @param  {Object}       [options]
   * @param  {Array}        [options.fields]                 Fields to insert (defaults to all fields)
   * @param  {Boolean}      [options.validate=false]         Should each row be subject to validation before it is inserted. The whole insert will fail if one row fails validation
   * @param  {Boolean}      [options.hooks=true]             Run before / after bulk create hooks?
   * @param  {Boolean}      [options.individualHooks=false]  Run before / after create hooks for each individ…