/*
The MIT License

Copyright (c) 2009-2010. Carlos Guzmán Álvarez. http://chronoswpf.codeplex.com/

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

using System.ComponentModel;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Markup;

namespace Chronos.Presentation.Controls
{
    /// <summary>
    /// Implemetation of a Split Button
    /// </summary>
    [ContentProperty("Items")]
    [DefaultProperty("Items")]
    public partial class SplitButton
        : Button
    {
        #region · Dependency Properties ·

        // AddOwner Dependency properties
        public static readonly DependencyProperty IsContextMenuOpenProperty =
                DependencyProperty.Register(
                    "IsContextMenuOpen",
                    typeof(bool),
                    typeof(SplitButton),
                    new FrameworkPropertyMetadata(false,
                            new PropertyChangedCallback(OnIsContextMenuOpenChanged)));
        
        public static readonly DependencyProperty PlacementProperty = 
                ContextMenuService.PlacementProperty.AddOwner(
                    typeof(SplitButton),
                    new FrameworkPropertyMetadata(PlacementMode.Bottom,
                        new PropertyChangedCallback(OnPlacementChanged)));

        public static readonly DependencyProperty PlacementRectangleProperty =
                ContextMenuService.PlacementRectangleProperty.AddOwner(
                    typeof(SplitButton),
                    new FrameworkPropertyMetadata(Rect.Empty,
                        new PropertyChangedCallback(OnPlacementRectangleChanged)));

        public static readonly DependencyProperty HorizontalOffsetProperty =
                ContextMenuService.HorizontalOffsetProperty.AddOwner(
                    typeof(SplitButton),
                    new FrameworkPropertyMetadata(0.0,
                        new PropertyChangedCallback(OnHorizontalOffsetChanged)));

        public static readonly DependencyProperty VerticalOffsetProperty =
                ContextMenuService.VerticalOffsetProperty.AddOwner(
                    typeof(SplitButton),
                    new FrameworkPropertyMetadata(0.0,
                        new PropertyChangedCallback(OnVerticalOffsetChanged)));

        #endregion

        #region · Dependency Properties Callbacks ·

        private static void OnIsContextMenuOpenChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            SplitButton s = (SplitButton)d;
            s.EnsureContextMenuIsValid();

            if (!s.ContextMenu.HasItems)
            {
                return;
            }

            bool value = (bool)e.NewValue;

            if (value && !s.ContextMenu.IsOpen)
            {
                s.ContextMenu.IsOpen = true;
            }
            else if (!value && s.ContextMenu.IsOpen)
            {
                s.ContextMenu.IsOpen = false;
            }
        }

        /// <summary>
        /// Placement Property changed callback, pass the value through to the buttons context menu
        /// </summary>
        private static void OnPlacementChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            SplitButton s = d as SplitButton;

            if (s == null)
            {
                return;
            }

            s.EnsureContextMenuIsValid();
            s.ContextMenu.Placement = (PlacementMode)e.NewValue;
        }

        /// <summary>
        /// PlacementRectangle Property changed callback, pass the value through to the buttons context menu
        /// </summary>
        private static void OnPlacementRectangleChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            SplitButton s = d as SplitButton;

            if (s == null)
            {
                return;
            }

            s.EnsureContextMenuIsValid();
            s.ContextMenu.PlacementRectangle = (Rect)e.NewValue;
        }

        /// <summary>
        /// HorizontalOffset Property changed callback, pass the value through to the buttons context menu
        /// </summary>
        private static void OnHorizontalOffsetChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            SplitButton s = d as SplitButton;

            if (s == null)
            {
                return;
            }

            s.EnsureContextMenuIsValid();
            s.ContextMenu.HorizontalOffset = (double)e.NewValue;
        }

        /// <summary>
        /// VerticalOffset Property changed callback, pass the value through to the buttons context menu
        /// </summary>
        private static void OnVerticalOffsetChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            SplitButton s = d as SplitButton;
            if (s == null)
            {
                return;
            }

            s.EnsureContextMenuIsValid();
            s.ContextMenu.VerticalOffset = (double)e.NewValue;
        }

        #endregion

        #region · Static Constructor ·

        /// <summary>
        /// Static Constructor
        /// </summary>
        static SplitButton()
        {
            DefaultStyleKeyProperty.OverrideMetadata(
                typeof(SplitButton),
                    new FrameworkPropertyMetadata(typeof(SplitButton)));
        }

        #endregion

        #region · Properties ·

        /// <summary>
        /// The Split Button's Items property maps to the base classes ContextMenu.Items property
        /// </summary>
        public ItemCollection Items
        {
            get
            {
                this.EnsureContextMenuIsValid();

                return this.ContextMenu.Items;
            }
        }

        /// <summary>
        /// Gets or sets the IsContextMenuOpen property. 
        /// </summary>
        public bool IsContextMenuOpen
        {
            get { return (bool)GetValue(IsContextMenuOpenProperty); }
            set { SetValue(IsContextMenuOpenProperty, value); }
        }

        /// <summary>
        /// Placement of the Context menu
        /// </summary>
        public PlacementMode Placement
        {
            get { return (PlacementMode)GetValue(PlacementProperty); }
            set { SetValue(PlacementProperty, value); }
        }

        /// <summary>
        /// PlacementRectangle of the Context menu
        /// </summary>
        public Rect PlacementRectangle
        {
            get { return (Rect)GetValue(PlacementRectangleProperty); }
            set { SetValue(PlacementRectangleProperty, value); }
        }

        /// <summary>
        /// HorizontalOffset of the Context menu
        /// </summary>
        public double HorizontalOffset
        {
            get { return (double)GetValue(HorizontalOffsetProperty); }
            set { SetValue(HorizontalOffsetProperty, value); }
        }

        /// <summary>
        /// VerticalOffset of the Context menu
        /// </summary>
        public double VerticalOffset
        {
            get { return (double)GetValue(VerticalOffsetProperty); }
            set { SetValue(VerticalOffsetProperty, value); }
        }

        #endregion

        #region · Constructors ·

        public SplitButton()
            : base()
        {
        }

        #endregion

        #region · Overriden Methods ·

        /// <summary>
        ///     Handles the Base Buttons OnClick event
        /// </summary>
        protected override void OnClick()
        {
            this.OnDropdown();
        }

        #endregion

        #region · Private Methods ·

        /// <summary>
        /// Make sure the Context menu is not null
        /// </summary>
        private void EnsureContextMenuIsValid()
        {
            if (this.ContextMenu == null)
            {
                this.ContextMenu                    = new ContextMenu();
                this.ContextMenu.PlacementTarget    = this;
                this.ContextMenu.Placement          = this.Placement;

                this.ContextMenu.Opened += ((sender, routedEventArgs) => IsContextMenuOpen = true);
                this.ContextMenu.Closed += ((sender, routedEventArgs) => IsContextMenuOpen = false);
            }
        }

        private void OnDropdown()
        {
            this.EnsureContextMenuIsValid();

            if (!this.ContextMenu.HasItems)
            {
                return;
            }

            this.ContextMenu.IsOpen = !IsContextMenuOpen; // open it if closed, close it if open
        }

        #endregion
    }
}