//******************************************************************************************************//  DataModelBase.cs - Gbtc////  Copyright © 2012, Grid Protection Alliance.  All Rights Reserved.////  Licensed to the Grid Protection Alliance (GPA) under one or more contributor license agreements. See//  the NOTICE file distributed with this work for additional information regarding copyright ownership.//  The GPA licenses this file to you under the MIT License (MIT), 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.opensource.org/licenses/MIT////  Unless agreed to in writing, the subject software distributed under the License is distributed on an//  "AS-IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. Refer to the//  License for the specific language governing permissions and limitations.////  Code Modification History://  ----------------------------------------------------------------------------------------------------//  03/25/2011 - Mehulbhai P Thakkar//       Generated original version of source code.//  04/08/2011 - J. Ritchie Carroll//       Modified class to use reflection to load default values and use entity property attributes.//  12/20/2012 - Starlynn Danyelle Gilliam//       Modified Header.////****************************************************************************************************** using System;using System.Collections.Concurrent;using System.Collections.Generic;using System.ComponentModel;using System.ComponentModel.DataAnnotations;using System.Linq;using System.Reflection;using System.Windows;using GSF.Collections;using GSF.Data;using GSF.Reflection; namespace GSF.TimeSeries.UI{    /// <summary>    /// Represents an abstract base class for all entity model objects.    /// </summary>    public abstract class DataModelBase : IDataModel    {        #region [ Members ]         // Constants         /// <summary>        /// The default timeout duration used for executing SQL statements.        /// </summary>        public const int DefaultTimeout = DataExtensions.DefaultTimeoutDuration;         // Events         /// <summary>        /// Raised when a property on this object has a new value.        /// </summary>        public event PropertyChangedEventHandler PropertyChanged;         // Fields        private readonly ConcurrentDictionary<string, string> m_propertyErrors;        private BindingFlags m_memberAccessBindingFlags;        private bool m_requireEntityPropertyAttribute;        private bool m_lastIsValidState;        private static bool m_messageFlag;         #endregion         #region [ Constructors ]         /// <summary>        /// Creates a new instance of the <see cref="DataModelBase"/> class.        /// </summary>        protected DataModelBase()            : this(false)        {        }         /// <summary>        /// Creates a new instance of the <see cref="DataModelBase"/> class.        /// </summary>        /// <param name="requireEntityPropertyAttribute">        /// Assigns flag that determines if <see cref="EntityPropertyAttribute"/> is required        /// to exist before a property is included as a field in the data model.        /// </param>        protected DataModelBase(bool requireEntityPropertyAttribute)            : this(true, requireEntityPropertyAttribute)        {        }         /// <summary>        /// Creates a new instance of the <see cref="DataModelBase"/> class.        /// </summary>        /// <param name="loadDefaults">        /// Determines whether to load default values into the properties using reflection.        /// </param>        /// <param name="requireEntityPropertyAttribute">        /// Assigns flag that determines if <see cref="EntityPropertyAttribute"/> is required        /// to exist before a property is included as a field in the data model.        /// </param>        protected DataModelBase(bool loadDefaults, bool requireEntityPropertyAttribute)        {            Action<PropertyInfo> propertyAction = property =>            {                object defaultValue = DeriveDefaultValue(property.Name, property.GetValue(this, null));                 if (!Common.IsDefaultValue(defaultValue))                    property.SetValue(this, defaultValue, null);                 OnPropertyChanged(property.Name);             };             m_propertyErrors = new ConcurrentDictionary<string, string>(StringComparer.OrdinalIgnoreCase);            m_memberAccessBindingFlags = BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly;            m_requireEntityPropertyAttribute = requireEntityPropertyAttribute;             if (loadDefaults)            {                // Load all default values for properties                ExecuteActionForProperties(propertyAction, property => (object)property.GetGetMethod() != null && (object)property.GetSetMethod() != null);            }        }         #endregion         #region [ Properties ]         /// <summary>        /// Indicates if the values associated with this object are valid.        /// </summary>        [EntityProperty(false)]        public bool IsValid        {            get            {                // If any of the properties have errors, values are not valid                m_lastIsValidState = m_propertyErrors.All(kvPair => string.IsNullOrWhiteSpace(kvPair.Value));                return m_lastIsValidState;            }        }         /// <summary>        /// Gets an error message indicating what is wrong with this object.        /// </summary>        /// <remarks>        /// An error message indicating what is wrong with this object. The default is an empty string ("").        /// </remarks>        [EntityProperty(false)]        public string Error        {            get            {                // Cumulate any properties with errors using line feed as delimiter                return m_propertyErrors.Where(kvPair => !string.IsNullOrWhiteSpace(kvPair.Value)).ToDelimitedString(Environment.NewLine);            }        }         /// <summary>        /// Gets the error message for the property with the given name.        /// </summary>        /// <param name="propertyName">The name of the property whose error message to get.</param>        /// <returns>The error message for the property. The default is an empty string ("").</returns>        public string this[string propertyName]        {            get            {                string error;                 if (!m_propertyErrors.TryGetValue(propertyName, out error))                    error = "";                 return error;            }        }         /// <summary>        /// Gets or sets flag that determines if <see cref="EntityPropertyAttribute"/> is        /// required to exist before a property is included as a field in the data model;        /// defaults to <c>false</c>.        /// </summary>        [Browsable(false), EntityProperty(false)]        public bool RequireEntityPropertyAttribute        {            get            {                return m_requireEntityPropertyAttribute;            }            set            {                m_requireEntityPropertyAttribute = value;            }        }         /// <summary>        /// Gets or sets <see cref="BindingFlags"/> used to access properties of derived class.        /// </summary>        /// <remarks>        /// Value defaults to <c><see cref="BindingFlags.Public"/> | <see cref="BindingFlags.Instance"/> | <see cref="BindingFlags.DeclaredOnly"/></c>.        /// </remarks>        [EditorBrowsable(EditorBrowsableState.Advanced), EntityProperty(false)]        protected virtual BindingFlags MemberAccessBindingFlags        {            get            {                return m_memberAccessBindingFlags;            }            set            {                m_memberAccessBindingFlags = value;            }        }         /// <summary>        /// gets or sets when the current <see cref="MessageFlag"/> 's Message Flag        /// </summary>        public static bool MessageFlag        {            get            {                return m_messageFlag;            }            set            {                m_messageFlag = value;            }        }         #endregion         #region [ Methods ]         /// <summary>        /// Raises the <see cref="PropertyChanged"/> event.        /// </summary>        /// <param name="propertyName">Property name that has changed.</param>        protected virtual void OnPropertyChanged(string propertyName)        {            if (PropertyChanged != null)                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));             if (string.Compare(propertyName, "IsValid", true) != 0)                ValidateProperty(propertyName);        }         /// <summary>        /// Validates current instance properties using Data Annotations.        /// </summary>        /// <param name="propertyName">This instance property to validate.</param>        /// <returns>Relevant error string on validation failure or <see cref="string.Empty"/> on validation success.</returns>        protected virtual void ValidateProperty(string propertyName)        {            if (string.IsNullOrEmpty(propertyName))                throw new ArgumentException("Invalid property name", propertyName);             string error = "";            object value = GetType().GetProperty(propertyName).GetValue(this, null);            List<ValidationResult> results = new List<ValidationResult>(1);             ValidationContext validationContext = new ValidationContext(this, null, null)            {                MemberName = propertyName            };             if (!Validator.TryValidateProperty(value, validationContext, results))            {                ValidationResult validationResult = results.First();                error = validationResult.ErrorMessage;            }             m_propertyErrors[propertyName] = error;             if (m_lastIsValidState != IsValid)                OnPropertyChanged("IsValid");        }         /// <summary>        /// Gets the default value specified by <see cref="DefaultValueAttribute"/>, if any, applied to the specified property.         /// </summary>        /// <param name="propertyName">Property name.</param>        /// <returns>Default value applied to specified property; or null if one does not exist.</returns>        /// <exception cref="ArgumentException"><paramref name="propertyName"/> cannot be null or empty.</exception>        public object GetDefaultValue(string propertyName)        {            if (string.IsNullOrEmpty(propertyName))                throw new ArgumentException("name cannot be null or empty");             return GetAttributeValue<DefaultValueAttribute, object>(propertyName, null, attribute => attribute.Value);        }         /// <summary>        /// Attempts to get best default value for given member.        /// </summary>        /// <param name="propertyName">Property name.</param>        /// <param name="value">Current property value.</param>        /// <remarks>        /// If <paramref name="value"/> is equal to its default(type) value, then any value derived from <see cref="DefaultValueAttribute"/> will be used instead.        /// </remarks>        /// <returns>The object that is the best default value.</returns>        [EditorBrowsable(EditorBrowsableState.Advanced)]        protected object DeriveDefaultValue(string propertyName, object value)        {            // See if value is equal to its default value (i.e., uninitialized)            if (Common.IsDefaultValue(value))            {                // See if any value exists in a DefaultValueAttribute                object defaultValue = GetDefaultValue(propertyName);                if (defaultValue != null)                    return defaultValue;            }             return value;        }         /// <summary>        /// Executes specified action over all public derived class properties.        /// </summary>        /// <param name="propertyAction">Action to execute for all properties.</param>        /// <param name="propertyFilter">Filter used to select which properties to execute the action.</param>        [EditorBrowsable(EditorBrowsableState.Advanced)]        protected void ExecuteActionForProperties(Action<PropertyInfo> propertyAction, Func<PropertyInfo, bool> propertyFilter)        {            PropertyInfo[] members = GetType()                .GetProperties(m_memberAccessBindingFlags)                .Where(propertyFilter)                .ToArray();             ExecuteActionForMembers(property =>            {                // Make sure only non-indexer properties are used for settings                if (property.GetIndexParameters().Length == 0)                    propertyAction(property);            }, members);        }         // Execute specified action over specified members        private void ExecuteActionForMembers<T>(Action<T> memberAction, T[] members) where T : MemberInfo        {            EntityPropertyAttribute attribute;             // Execute action for each member            foreach (T member in members)            {                // See if serialize setting attribute exists                if (member.TryGetAttribute(out attribute))                {                    // Found entity property attribute, perform action if include is true                    if (attribute.Include)                        memberAction(member);                }                else if (!m_requireEntityPropertyAttribute)                {                    // Didn't find entity property attribute and it's not required, so we perform action (i.e., assume include)                    memberAction(member);                }            }        }         /// <summary>        /// Attempts to find specified attribute and return specified value.        /// </summary>        /// <typeparam name="TAttribute">Type of <see cref="Attribute"/> to find.</typeparam>        /// <typeparam name="TValue">Type of value attribute delegate returns.</typeparam>        /// <param name="propertyName">Name of property to search for attribute.</param>        /// <param name="defaultValue">Default value to return if attribute doesn't exist.</param>        /// <param name="attributeValue">Function delegate used to return desired attribute property.</param>        /// <returns>Specified attribute value if it exists; otherwise default value.</returns>        [EditorBrowsable(EditorBrowsableState.Advanced)]        protected TValue GetAttributeValue<TAttribute, TValue>(string propertyName, TValue defaultValue, Func<TAttribute, TValue> attributeValue) where TAttribute : Attribute        {            TAttribute attribute;             // See if property exists with specified name            PropertyInfo property = this.GetType().GetProperty(propertyName, m_memberAccessBindingFlags);             if (property != null)            {                // See if attribute exists on property                if (property.TryGetAttribute(out attribute))                {                    // Return value as specified by delegate                    return attributeValue(attribute);                }                 // Attribute wasn't found, return default value                return defaultValue;            }             // Return default value            return defaultValue;        }         #endregion         #region [ Static ]         // Static Methods         /// <summary>        /// Creates and instance of <see cref="AdoDataConnection"/> if it is null.        /// </summary>        /// <param name="database">Reference parameter representing <see cref="AdoDataConnection"/> object.</param>        /// <returns>Boolean, true if new instance of <see cref="AdoDataConnection"/> is created otherwise false.</returns>        public static bool CreateConnection(ref AdoDataConnection database)        {            if (database == null)            {                try                {                    database = new AdoDataConnection(CommonFunctions.DefaultSettingsCategory);                    return true;                }                catch (Exception ex)                {                    throw;                    if (!MessageFlag)                    {                        m_messageFlag = true;                        MessageBox.Show("ERROR: " + ex.Message, "Create Database Connection", MessageBoxButton.OK);                        m_messageFlag = false;                    }                    return false;                }            }             return false;        }         #endregion    }}