using System;

using System.Collections.Generic;

using System.Collections.ObjectModel;

using System.Collections.Specialized;

using System.ComponentModel;

using System.Linq;

using System.Linq.Expressions;

using System.Runtime.Serialization;

using System.Text;



namespace Nova.AppFramework

{

    /// <summary>

    ///   Extends <see cref = "INotifyPropertyChanged" /> such that the change event can be raised by external parties.

    /// </summary>

    public interface INotifyPropertyChangedEx : INotifyPropertyChanged

    {

        /// <summary>

        ///   Enables/Disables property change notification.

        /// </summary>

        bool IsNotifying { get; set; }



        /// <summary>

        ///   Notifies subscribers of the property change.

        /// </summary>

        /// <param name = "propertyName">Name of the property.</param>

        void NotifyOfPropertyChange(string propertyName);



        /// <summary>

        ///   Raises a change notification indicating that all bindings should be refreshed.

        /// </summary>

        void Refresh();

    }



    [Serializable]



    /// <summary>

    ///   A base class that implements the infrastructure for property change notification and automatically performs UI thread marshalling.

    /// </summary>

    public class PropertyChangedBase : INotifyPropertyChangedEx

    {

        /// <summary>

        ///   Creates an instance of <see cref = "PropertyChangedBase" />.

        /// </summary>

        public PropertyChangedBase()

        {

            executor = new SafeExecutor(this);

            IsNotifying = true;

        }



        [field: NonSerialized]

        /// <summary>

        ///   Occurs when a property value changes.

        /// </summary>

        public event PropertyChangedEventHandler PropertyChanged = delegate { };



        [field: NonSerialized]

        SafeExecutor executor;



        [field: NonSerialized]

        bool isNotifying; //serializator try to serialize even autogenerated fields



        /// <summary>

        ///   Enables/Disables property change notification.

        /// </summary>

        public bool IsNotifying

        {

            get { return isNotifying; }

            set { isNotifying = value; }

        }



        /// <summary>

        ///   Raises a change notification indicating that all bindings should be refreshed.

        /// </summary>

        public void Refresh()

        {

            NotifyOfPropertyChange(string.Empty);

        }



        /// <summary>

        ///   Notifies subscribers of the property change.

        /// </summary>

        /// <param name = "propertyName">Name of the property.</param>

        public virtual void NotifyOfPropertyChange(string propertyName)

        {

            if (IsNotifying)

                executor.ExecuteOnUIThread(() => RaisePropertyChangedEventCore(propertyName));

        }



        /// <summary>

        ///   Notifies subscribers of the property change.

        /// </summary>

        /// <typeparam name = "TProperty">The type of the property.</typeparam>

        /// <param name = "property">The property expression.</param>

        public virtual void NotifyOfPropertyChange<TProperty>(Expression<Func<TProperty>> property)

        {

            NotifyOfPropertyChange(property.GetMemberInfo().Name);

        }



        /// <summary>

        ///   Raises the property changed event immediately.

        /// </summary>

        /// <param name = "propertyName">Name of the property.</param>

        public virtual void RaisePropertyChangedEventImmediately(string propertyName)

        {

            if (IsNotifying)

                RaisePropertyChangedEventCore(propertyName);

        }



        void RaisePropertyChangedEventCore(string propertyName)

        {

            var handler = PropertyChanged;

            if (handler != null)

                handler(this, new PropertyChangedEventArgs(propertyName));

        }



        [OnDeserialized]

        void OnDeserialized(StreamingContext c)

        {

            IsNotifying = true;

        }

    }



    /// <summary>

    ///   Represents a collection that is observable.

    /// </summary>

    /// <typeparam name = "T">The type of elements contained in the collection.</typeparam>

    public interface IObservableCollection<T> : IList<T>, INotifyPropertyChangedEx, INotifyCollectionChanged

    {

        /// <summary>

        ///   Adds the range.

        /// </summary>

        /// <param name = "items">The items.</param>

        void AddRange(IEnumerable<T> items);



        /// <summary>

        ///   Removes the range.

        /// </summary>

        /// <param name = "items">The items.</param>

        void RemoveRange(IEnumerable<T> items);

    }



    /// <summary>

    /// A base collection class that supports automatic UI thread marshalling.

    /// </summary>

    /// <typeparam name="T">The type of elements contained in the collection.</typeparam>

    [Serializable]

    public class BindableCollection<T> : ObservableCollection<T>, IObservableCollection<T>

    {

        /// <summary>

        ///   Initializes a new instance of the <see cref = "Illusion.BindableCollection{T}" /> class.

        /// </summary>

        public BindableCollection()

        {

            IsNotifying = true;

            executor = new SafeExecutor(this);

        }



        [field:NonSerialized]

        SafeExecutor executor;



        /// <summary>

        ///   Initializes a new instance of the <see cref = "Illusion.BindableCollection{T}" /> class.

        /// </summary>

        /// <param name = "collection">The collection from which the elements are copied.</param>

        /// <exception cref = "T:System.ArgumentNullException">

        ///   The <paramref name = "collection" /> parameter cannot be null.

        /// </exception>

        public BindableCollection(IEnumerable<T> collection)

        {

            IsNotifying = true;

            AddRange(collection);

        }



        [field: NonSerialized]

        bool isNotifying; //serializator try to serialize even autogenerated fields



        /// <summary>

        ///   Enables/Disables property change notification.

        /// </summary>

        public bool IsNotifying

        {

            get { return isNotifying; }

            set { isNotifying = value; }

        }



        /// <summary>

        ///   Notifies subscribers of the property change.

        /// </summary>

        /// <param name = "propertyName">Name of the property.</param>

        public void NotifyOfPropertyChange(string propertyName)

        {

            if (IsNotifying)

                executor.ExecuteOnUIThread(() => RaisePropertyChangedEventImmediately(new PropertyChangedEventArgs(propertyName)));

        }



        /// <summary>

        ///   Raises a change notification indicating that all bindings should be refreshed.

        /// </summary>

        public void Refresh()

        {

            executor.ExecuteOnUIThread(() =>

            {

                OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));

                OnPropertyChanged(new PropertyChangedEventArgs(string.Empty));

            });

        }



        /// <summary>

        ///   Inserts the item to the specified position.

        /// </summary>

        /// <param name = "index">The index to insert at.</param>

        /// <param name = "item">The item to be inserted.</param>

        protected override sealed void InsertItem(int index, T item)

        {

            executor.ExecuteOnUIThread(() => InsertItemBase(index, item));

        }



        /// <summary>

        ///   Exposes the base implementation of the <see cref = "InsertItem" /> function.

        /// </summary>

        /// <param name = "index">The index.</param>

        /// <param name = "item">The item.</param>

        /// <remarks>

        ///   Used to avoid compiler warning regarding unverifiable code.

        /// </remarks>

        protected virtual void InsertItemBase(int index, T item)

        {

            base.InsertItem(index, item);

        }



#if NET

    /// <summary>

    /// Moves the item within the collection.

    /// </summary>

    /// <param name="oldIndex">The old position of the item.</param>

    /// <param name="newIndex">The new position of the item.</param>

        protected sealed override void MoveItem(int oldIndex, int newIndex) {

            Execute.OnUIThread(() => MoveItemBase(oldIndex, newIndex));

        }



        /// <summary>

        /// Exposes the base implementation fo the <see cref="MoveItem"/> function.

        /// </summary>

        /// <param name="oldIndex">The old index.</param>

        /// <param name="newIndex">The new index.</param>

        /// <remarks>Used to avoid compiler warning regarding unverificable code.</remarks>

        protected virtual void MoveItemBase(int oldIndex, int newIndex) {

            base.MoveItem(oldIndex, newIndex);

        }

#endif



        /// <summary>

        ///   Sets the item at the specified position.

        /// </summary>

        /// <param name = "index">The index to set the item at.</param>

        /// <param name = "item">The item to set.</param>

        protected override sealed void SetItem(int index, T item)

        {

            executor.ExecuteOnUIThread(() => SetItemBase(index, item));

        }



        /// <summary>

        ///   Exposes the base implementation of the <see cref = "SetItem" /> function.

        /// </summary>

        /// <param name = "index">The index.</param>

        /// <param name = "item">The item.</param>

        /// <remarks>

        ///   Used to avoid compiler warning regarding unverifiable code.

        /// </remarks>

        protected virtual void SetItemBase(int index, T item)

        {

            base.SetItem(index, item);

        }



        /// <summary>

        ///   Removes the item at the specified position.

        /// </summary>

        /// <param name = "index">The position used to identify the item to remove.</param>

        protected override sealed void RemoveItem(int index)

        {

            executor.ExecuteOnUIThread(() => RemoveItemBase(index));

        }



        /// <summary>

        ///   Exposes the base implementation of the <see cref = "RemoveItem" /> function.

        /// </summary>

        /// <param name = "index">The index.</param>

        /// <remarks>

        ///   Used to avoid compiler warning regarding unverifiable code.

        /// </remarks>

        protected virtual void RemoveItemBase(int index)

        {

            base.RemoveItem(index);

        }



        /// <summary>

        ///   Clears the items contained by the collection.

        /// </summary>

        protected override sealed void ClearItems()

        {

            executor.ExecuteOnUIThread(ClearItemsBase);

        }



        /// <summary>

        ///   Exposes the base implementation of the <see cref = "ClearItems" /> function.

        /// </summary>

        /// <remarks>

        ///   Used to avoid compiler warning regarding unverifiable code.

        /// </remarks>

        protected virtual void ClearItemsBase()

        {

            base.ClearItems();

        }



        /// <summary>

        ///   Raises the <see cref = "E:System.Collections.ObjectModel.ObservableCollection`1.CollectionChanged" /> event with the provided arguments.

        /// </summary>

        /// <param name = "e">Arguments of the event being raised.</param>

        protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)

        {

            if (IsNotifying)

                base.OnCollectionChanged(e);

        }



        /// <summary>

        ///   Raises the PropertyChanged event with the provided arguments.

        /// </summary>

        /// <param name = "e">The event data to report in the event.</param>

        protected override void OnPropertyChanged(PropertyChangedEventArgs e)

        {

            if (IsNotifying)

                base.OnPropertyChanged(e);

        }



        void RaisePropertyChangedEventImmediately(PropertyChangedEventArgs e)

        {

            OnPropertyChanged(e);

        }



        /// <summary>

        ///   Adds the range.

        /// </summary>

        /// <param name = "items">The items.</param>

        public virtual void AddRange(IEnumerable<T> items)

        {

            executor.ExecuteOnUIThread(() =>

            {

                var previousNotificationSetting = IsNotifying;

                IsNotifying = false;

                var index = Count;

                foreach (var item in items)

                {

                    InsertItemBase(index, item);

                    index++;

                }

                IsNotifying = previousNotificationSetting;

                OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));

                OnPropertyChanged(new PropertyChangedEventArgs(string.Empty));

            });

        }



        /// <summary>

        ///   Removes the range.

        /// </summary>

        /// <param name = "items">The items.</param>

        public virtual void RemoveRange(IEnumerable<T> items)

        {

            executor.ExecuteOnUIThread(() =>

            {

                var previousNotificationSetting = IsNotifying;

                IsNotifying = false;

                foreach (var item in items)

                {

                    var index = IndexOf(item);

                    RemoveItemBase(index);

                }

                IsNotifying = previousNotificationSetting;

                OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));

                OnPropertyChanged(new PropertyChangedEventArgs(string.Empty));

            });

        }



        [OnDeserialized]

        void OnDeserialized(StreamingContext c)

        {

            IsNotifying = true;

        }

    }

}