using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Linq.Expressions;
using JD.Kernel.StaticHelpers;

namespace JD.MessageService
{
    /// <summary>
    /// An extended message box.
    /// </summary>
    /// <remarks>
    /// Uses TaskDialogs on Vista and more recent
    /// </remarks>
    public class MessageDialog
    {
        #region Constants

        internal const int CustomButtonStartId = 0x101;

        #endregion

        #region Variables

        private readonly List<Button> m_buttons = new List<Button>();
        private int m_defaultButtonId;
        private int m_nextButtonId = CustomButtonStartId; // Make sure not to clash with TaskDialog common buttons

        private string m_caption;
        private string m_mainMessage;
        private string m_content;

        #endregion

        #region Constructor

        public MessageDialog()
        {
            Flags = MessageDialogFlags.UseCommandLinks;
        }

        #endregion

        #region Properties

        /// <summary>
        /// Dialog title.
        /// </summary>
        public string Caption
        {
            get { return m_caption; }
            set
            {
                if (m_caption != value)
                {
                    m_caption = value;
                    OnPropertyChanged(d => d.Caption);
                }
            }
        }

        /// <summary>
        /// Main message (displayed at top of dialog).
        /// </summary>
        public string MainMessage
        {
            get { return m_mainMessage; }
            set
            {
                if (m_mainMessage != value)
                {
                    m_mainMessage = value;
                    OnPropertyChanged(d => d.MainMessage);
                }
            }
        }

        /// <summary>
        /// Content message (displayed in main body of dialog).
        /// </summary>
        public string Content
        {
            get { return m_content; }
            set
            {
                if (m_content != value)
                {
                    m_content = value;
                    OnPropertyChanged(d => d.Content);
                }
            }
        }

        /// <summary>
        /// Icon displayed besides the main message.
        /// </summary>
        public MessageDialogIcon MainIcon
        {
            get;
            set;
        }

        public IList<Button> Buttons
        {
            get { return m_buttons.AsReadOnly(); }
        }

        public MessageDialogFlags Flags
        {
            get;
            set;
        }

        public string CheckBoxText
        {
            get;
            set;
        }

        public bool IsChecked
        {
            get;
            set;
        }

        public bool EscapeKeyReturnsNull
        {
            get;
            set;
        }

        /// <summary>
        /// If greater than 0, ProgressBarUpdateRequest event will be raised asking for current progress.
        /// </summary>
        public int ProgressBarMaximum
        {
            get;
            set;
        }

        internal bool ShouldTick
        {
            get { return Tick != null; }
        }

        /// <summary>
        /// Center the dialog on the owner window rather than the monitor.
        /// </summary>
        public bool PositionRelativeToParent
        {
            get; set;
        }

        #endregion

        #region Methods

        public Button AddButton(string text)
        {
            var button = new Button(this, m_nextButtonId++, text);
            m_buttons.Add(button);
            return button;
        }

        public Button AddCommonButton(MessageDialogCommonButton button)
        {
            Throw.InvalidArgumentIf((int)button >= CustomButtonStartId, "Invalid button", "button");
            Throw.InvalidArgumentIf(m_buttons.Any(b => b.Id == (int)button), "There's already another button with that id", "button");

            var theButton = new Button(this, (int)button, button.ToString());
            m_buttons.Add(theButton);
            return theButton;
        }

        public Button ShowDialog()
        {
            Throw.InvalidOperationIf(m_buttons.Count == 0, "Cannot ShowDialog without buttons");

            if (string.IsNullOrEmpty(Caption))
            {
                Caption = AppDomain.CurrentDomain.FriendlyName;
            }

            return MessageService.Instance.ShowMessageDialog(this);
        }

        #endregion

        #region Events

        public event EventHandler<TickEventArgs> Tick;

        internal void OnTick(TickEventArgs e)
        {
            Tick?.Invoke(this, e);
        }

        internal event PropertyChangedEventHandler PropertyChanged;

        private void OnPropertyChanged(Expression<Func<MessageDialog, object>> func)
        {
            string name = MemberNameResolver.ResolveMemberName(func);
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
        }

        #endregion

        #region Inner Types

        public class Button
        {
            #region Variables

            private readonly MessageDialog m_owner;
            private readonly int m_id;
            private readonly string m_text;

            private string m_content;
            private bool m_enabled = true;

            #endregion

            #region Constructor

            internal Button(MessageDialog owner, int id, string text)
            {
                m_owner = owner;
                m_id = id;
                m_text = text;
            }

            #endregion

            #region Properties

            public int Id
            {
                get { return m_id; }
            }

            public string Text
            {
                get { return m_text; }
            }

            public bool IsDefault
            {
                get { return m_owner.m_defaultButtonId == Id; }
                set
                {
                    if (value)
                    {
                        m_owner.m_defaultButtonId = Id;
                    }
                    else if (IsDefault)
                    {
                        m_owner.m_defaultButtonId = 0;
                    }
                }
            }

            public string Content
            {
                get { return m_content; }
                set
                {
                    Throw.InvalidOperationIf(IsCommonButton, "Cannot set a content on common buttons");
                    m_content = value;
                }
            }

            public bool Enabled
            {
                get { return m_enabled; }
                set { m_enabled = value; }
            }


            public bool IsCommonButton
            {
                get { return Id < CustomButtonStartId; }
            }

            public object Tag
            {
                get;
                set;
            }

            #endregion
        }

        public class TickEventArgs : EventArgs
        {
            private readonly TimeSpan m_deltaTime;

            public TickEventArgs(TimeSpan deltaTime)
            {
                CurrentProgress = -1;
                m_deltaTime += deltaTime;
            }

            public TimeSpan DeltaTime
            {
                get { return m_deltaTime; }
            }

            public int CurrentProgress
            {
                get;
                set;
            }

            internal MessageDialog NewDialog
            {
                get;
                private set;
            }
        }

        #endregion
    }
}