#region Apache Notice
/*****************************************************************************
 * $Revision: 450157 $
 * $LastChangedDate$
 * $LastChangedBy$
 * 
 * iBATIS.NET Data Mapper
 * Copyright (C) 2006/2005 - The Apache Software Foundation
 *  
 * 
 * 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.
 * 
 ********************************************************************************/
#endregion

#region Using

using System;
using System.Collections.Specialized;
using System.Data;
using System.Xml.Serialization;
using Apache.Ibatis.Common.Utilities.Objects;
using Apache.Ibatis.DataMapper.DataExchange;
using Apache.Ibatis.Common.Utilities;

#endregion

namespace Apache.Ibatis.DataMapper.Configuration.ResultMapping
{
    /// <summary>
    /// Implementation of <see cref="IResultMap"/> interface for auto mapping
    /// </summary>
    public class AutoResultMap : IResultMap 
    {
        [NonSerialized]
        private bool _isInitalized = false;
        [NonSerialized]
        private Type _resultClass = null;
        [NonSerialized]
        private IFactory _resultClassFactory = null;
        [NonSerialized]
        private ResultPropertyCollection _properties = new ResultPropertyCollection();

        [NonSerialized]
        private IDataExchange _dataExchange = null;

        /// <summary>
        /// Initializes a new instance of the <see cref="AutoResultMap"/> class.
        /// </summary>
        /// <param name="resultClass">The result class.</param>
        /// <param name="resultClassFactory">The result class factory.</param>
        /// <param name="dataExchange">The data exchange.</param>
        public AutoResultMap(Type resultClass, IFactory resultClassFactory, IDataExchange dataExchange)
        {
            _resultClass = resultClass;
            _resultClassFactory = resultClassFactory;
            _dataExchange = dataExchange;
        }
        
        #region IResultMap Members

        /// <summary>
        /// The GroupBy Properties.
        /// </summary>
        [XmlIgnore]
        public StringCollection GroupByPropertyNames
        {
            get { throw new NotImplementedException("The property 'GroupByPropertyNames' is not implemented."); }
        }
        
        /// <summary>
        /// The collection of ResultProperty.
        /// </summary>
        [XmlIgnore]
        public ResultPropertyCollection Properties
        {
            get { return _properties; }
        }

        /// <summary>
        /// The GroupBy Properties.
        /// </summary>
        /// <value></value>
        public ResultPropertyCollection GroupByProperties
        {
            get { throw new NotImplementedException("The property 'GroupByProperties' is not implemented."); }
        }

        /// <summary>
        /// The collection of constructor parameters.
        /// </summary>
        [XmlIgnore]
        public ResultPropertyCollection Parameters
        {
            get { throw new NotImplementedException("The property 'Parameters' is not implemented."); }
        }

        /// <summary>
        /// Gets or sets a value indicating whether this instance is initalized.
        /// </summary>
        /// <value>
        /// 	<c>true</c> if this instance is initalized; otherwise, <c>false</c>.
        /// </value>
        public bool IsInitalized
        {
            get { return _isInitalized; }
            set { _isInitalized = value; }
        }

        /// <summary>
        /// Identifier used to identify the resultMap amongst the others.
        /// </summary>
        /// <value></value>
        /// <example>GetProduct</example>
        public string Id
        {
            get { return _resultClass.Name; }
        }


        /// <summary>
        /// The output type class of the resultMap.
        /// </summary>
        /// <value></value>
        public Type Class
        {
            get { return _resultClass; }
        }


        /// <summary>
        /// Sets the IDataExchange
        /// </summary>
        /// <value></value>
        public IDataExchange DataExchange
        {
            set { _dataExchange = value; }
        }


        /// <summary>
        /// Create an instance Of result.
        /// </summary>
        /// <param name="parameters">An array of values that matches the number, order and type
        /// of the parameters for this constructor.</param>
        /// <returns>An object.</returns>
        public object CreateInstanceOfResult(object[] parameters)
        {
            return CreateInstanceOfResultClass();
        }

        /// <summary>
        /// Set the value of an object property.
        /// </summary>
        /// <param name="target">The object to set the property.</param>
        /// <param name="property">The result property to use.</param>
        /// <param name="dataBaseValue">The database value to set.</param>
        public void SetValueOfProperty(ref object target, ResultProperty property, object dataBaseValue)
        {
            _dataExchange.SetData(ref target, property, dataBaseValue);
        }

        /// <summary>
        /// </summary>
        /// <param name="dataReader"></param>
        /// <returns></returns>
        public IResultMap ResolveSubMap(IDataReader dataReader)
        {
           return this;
        }

        #endregion

        /// <summary>
        /// Clones this instance.
        /// </summary>
        /// <returns></returns>
        public AutoResultMap Clone()
        {
            return new AutoResultMap(_resultClass, _resultClassFactory, _dataExchange);
        }
        
        /// <summary>
        /// Create an instance of result class.
        /// </summary>
        /// <returns>An object.</returns>
        public object CreateInstanceOfResultClass()
        {
            if (_resultClass.IsPrimitive || _resultClass == typeof(string))
            {
                TypeCode typeCode = Type.GetTypeCode(_resultClass);
                return TypeUtils.InstantiatePrimitiveType(typeCode);
            }
            else
            {
                if (_resultClass.IsValueType)
                {
                    if (_resultClass == typeof(DateTime))
                    {
                        return new DateTime();
                    }
                    else if (_resultClass == typeof(Decimal))
                    {
                        return new Decimal();
                    }
                    else if (_resultClass == typeof(Guid))
                    {
                        return Guid.Empty;
                    }
                    else if (_resultClass == typeof(TimeSpan))
                    {
                        return new TimeSpan(0);
                    }
                    else if (_resultClass.IsGenericType && typeof(Nullable<>).IsAssignableFrom(_resultClass.GetGenericTypeDefinition()))
                    {
                        return TypeUtils.InstantiateNullableType(_resultClass);
                    }
                    else
                    {
                        throw new NotImplementedException("Unable to instanciate value type");
                    }
                }
                else
                {
                    return _resultClassFactory.CreateInstance(null);
                }
            }
        }

    }
}