using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Watchdog.WatchdogLib.Win32;
using System.Windows.Forms;
using System.Drawing;
using System.ComponentModel;
using WPFWin = System.Windows;
using WPFWinInterop = System.Windows.Interop;

namespace Watchdog.WatchdogLib.WinForms
{
    /// <summary>
    /// MsgBox is a WindowsForms MessageBox that can be centered to the Parent
    /// </summary>
    public static class MsgBox
    {
        #region Private Static Members

        private static User32.WindowsHookProc _hookProcDelegate = null;
        private static int _hHook = 0;
        private static string _title = null;
        private static string _msg = null;
        private static IntPtr _hIcon = IntPtr.Zero;
        private static bool _IsDesktopOwner = false;
        private static bool _ShowFatal = false;

        // Delegate to make All Message Boxes Thread-Safe
        private delegate DialogResult ShowMsgBoxDelegate(IWin32Window parent, String Title, String Text, MessageBoxButtons MsgBoxButtons, MessageBoxIcon MsgBoxIcon, Icon TitleBarIcon);

        #endregion

        #region Public Properties

        public static Icon DefaultTitleBarIcon { get; set; }
        public static uint MaxNumberOfCharactersPerLine { get; set; }
        public const uint DefaultNumberOfCharactersPerLine = 62;

        #endregion

        #region Public Header Properties

        public static bool ShowHeader { get; set; }
        public static string MsgBox_ErrorHeader { get; set; }
        public static string MsgBox_FatalErrorHeader { get; set; }
        public static string MsgBox_WarningHeader { get; set; }
        public static string MsgBox_InfoHeader { get; set; }

        #endregion

        #region Public Footer Properties

        public static bool ShowFooter { get; set; }
        public static string MsgBox_ErrorFooter { get; set; }
        public static string MsgBox_FatalErrorFooter { get; set; }
        public static string MsgBox_WarningFooter { get; set; }
        public static string MsgBox_InfoFooter { get; set; }

        #endregion

        #region Public Title Header Properties

        public static bool ShowTitleHeader { get; set; }
        public static string MsgBox_ErrorTitleHeader { get; set; }
        public static string MsgBox_FatalErrorTitleHeader { get; set; }
        public static string MsgBox_WarningTitleHeader { get; set; }
        public static string MsgBox_InfoTitleHeader { get; set; }

        #endregion

        #region Construction

        static MsgBox()
        {
            DefaultTitleBarIcon = null;
            MaxNumberOfCharactersPerLine = DefaultNumberOfCharactersPerLine;

            // Header Init
            MsgBox_FatalErrorHeader = String.Empty;
            MsgBox_ErrorHeader = String.Empty;
            MsgBox_WarningHeader = String.Empty;
            MsgBox_InfoHeader = String.Empty;
            ShowHeader = true;

            // Footer Init
            MsgBox_FatalErrorFooter = String.Empty;
            MsgBox_ErrorFooter = String.Empty;
            MsgBox_WarningFooter = String.Empty;
            MsgBox_InfoFooter = String.Empty;
            ShowFooter = true;

            // Title Header Init
            MsgBox_FatalErrorTitleHeader = String.Empty;
            MsgBox_ErrorTitleHeader = String.Empty;
            MsgBox_WarningTitleHeader = String.Empty;
            MsgBox_InfoTitleHeader = String.Empty;
            ShowTitleHeader = true;
        }

        #endregion

        #region Public Static Methods

        /// <summary>
        /// Shows a custom Message Box (centered to parent), with the DefaultTitleBarIcon 
        /// </summary>
        public static DialogResult Show(WPFWin.Window parent, String Title, String Text, MessageBoxButtons MsgBoxButtons, MessageBoxIcon MsgBoxIcon)
        {
            if (parent != null)
            {
                WPFWinInterop.WindowInteropHelper interop = new WPFWinInterop.WindowInteropHelper(parent);
                if(interop.Handle != IntPtr.Zero)
                   return Show(Watchdog.WatchdogLib.Win32.Convert.ConverthWndToIWin32Window(interop.Handle), Title, Text, MsgBoxButtons, MsgBoxIcon, DefaultTitleBarIcon);
            }
            return Show(Functions.GetDestopWindow(), Title, Text, MsgBoxButtons, MsgBoxIcon, DefaultTitleBarIcon);
        }

        /// <summary>
        /// Shows a custom Message Box (centered to parent), with the DefaultTitleBarIcon 
        /// </summary>
        public static DialogResult Show(IWin32Window parent, String Title, String Text, MessageBoxButtons MsgBoxButtons, MessageBoxIcon MsgBoxIcon)
        {
            return Show(parent, Title, Text, MsgBoxButtons, MsgBoxIcon, DefaultTitleBarIcon);
        }

        /// <summary>
        /// Shows a custom Message Box (centered to Desktop), with the DefaultTitleBarIcon
        /// </summary>
        public static DialogResult Show(String Title, String Text, MessageBoxButtons MsgBoxButtons, MessageBoxIcon MsgBoxIcon)
        {
            return Show(Functions.GetDestopWindow(), Title, Text, MsgBoxButtons, MsgBoxIcon, DefaultTitleBarIcon);
        }

        /// <summary>
        /// *Main MessageBox Show Function* allows you to center the Message Box to the Parent
        /// </summary>
        /// <returns>Result of Dialog </returns>
        public static DialogResult Show(IWin32Window parent, String Title, String Text, MessageBoxButtons MsgBoxButtons, MessageBoxIcon MsgBoxIcon, Icon TitleBarIcon)
        {
            ISynchronizeInvoke InvokeObject = null;
            if (parent != null && parent is ISynchronizeInvoke)
                InvokeObject = (ISynchronizeInvoke)parent;

            // Invoke if we need to * Make MessageBoxes generally Thread-safe *
            if ((InvokeObject != null) && InvokeObject.InvokeRequired)
            {
                DialogResult result = (DialogResult)InvokeObject.Invoke(new ShowMsgBoxDelegate(MsgBox.Show), new object[] { parent, Title, Text, MsgBoxButtons, MsgBoxIcon, TitleBarIcon });
                return result;
            }
            else
            {
                return MsgBox.ShowInternal(parent, Text, Title, MsgBoxButtons, MsgBoxIcon, TitleBarIcon);
            }
        }

        #endregion

        #region Public Static Methods Extended

        /// <summary>
        /// Shows Warning MessageBox
        /// </summary>
        //public static DialogResult ShowWarning(IWin32Window parent, String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowWarning(IWin32Window parent, String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(parent, Title, Text, MsgBoxButtons, MessageBoxIcon.Exclamation);
        }

        /// <summary>
        /// Shows Warning MessageBox
        /// </summary>
        //public static DialogResult ShowWarning(String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowWarning(String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(Title, Text, MsgBoxButtons, MessageBoxIcon.Exclamation);
        }

        /// <summary>
        /// Shows Fatal Error MessageBox
        /// </summary>
        //public static DialogResult ShowFatalError(IWin32Window parent, String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowFatalError(IWin32Window parent, String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            _ShowFatal = true;
            DialogResult dr = Show(parent, Title, Text, MsgBoxButtons, MessageBoxIcon.Error);
            _ShowFatal = false;
            return dr;
        }

        /// <summary>
        /// Shows Fatal Error MessageBox
        /// </summary>
        //public static DialogResult ShowFatalError(String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowFatalError(String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            _ShowFatal = true;
            DialogResult dr = Show(Title, Text, MsgBoxButtons, MessageBoxIcon.Error);
            _ShowFatal = false;
            return dr;
        }

        /// <summary>
        /// Shows Error MessageBox
        /// </summary>
        //public static DialogResult ShowError(IWin32Window parent, String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowError(IWin32Window parent, String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(parent, Title, Text, MsgBoxButtons, MessageBoxIcon.Error);
        }

        /// <summary>
        /// Shows Error MessageBox
        /// </summary>
        //public static DialogResult ShowError(String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowError(String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(Title, Text, MsgBoxButtons, MessageBoxIcon.Error);
        }

        /// <summary>
        /// Shows Information MessageBox
        /// </summary>
        //public static DialogResult ShowInfo(IWin32Window parent, String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowInfo(IWin32Window parent, String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(parent, Title, Text, MsgBoxButtons, MessageBoxIcon.Information);
        }

        /// <summary>
        /// Shows Information MessageBox
        /// </summary>
        //public static DialogResult ShowInfo(String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowInfo(String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(Title, Text, MsgBoxButtons, MessageBoxIcon.Information);
        }

        /// <summary>
        /// Shows Default MessageBox
        /// </summary>
        //public static DialogResult ShowDefault(IWin32Window parent, String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowDefault(IWin32Window parent, String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(parent, Title, Text, MsgBoxButtons, MessageBoxIcon.None);
        }

        /// <summary>
        /// Shows Default MessageBox
        /// </summary>
        //public static DialogResult ShowDefault(String Text, String Title = "", MessageBoxButtons MsgBoxButtons = MessageBoxButtons.OK)
        public static DialogResult ShowDefault(String Text, String Title, MessageBoxButtons MsgBoxButtons)
        {
            return Show(Title, Text, MsgBoxButtons, MessageBoxIcon.None);
        }

        #endregion

        #region Private Methods

        /// <summary>
        /// 
        /// </summary>
        /// <param name="owner"></param>
        /// <param name="msg"></param>
        /// <param name="title"></param>
        /// <param name="btns"></param>
        /// <param name="icon"></param>
        /// <param name="TitleBarIcon"></param>
        /// <returns></returns>
        private static DialogResult ShowInternal(IWin32Window owner, string msg, string title, MessageBoxButtons btns, MessageBoxIcon icon, Icon TitleBarIcon)
        {
            // Create a callback delegate
            _hookProcDelegate = new User32.WindowsHookProc(HookCallback);

            #region Header Action
            if (ShowHeader)
            {
                if (icon == MessageBoxIcon.Error && !String.IsNullOrEmpty(MsgBox_FatalErrorHeader) && _ShowFatal)
                    msg = MsgBox_FatalErrorHeader + msg;
                else if (icon == MessageBoxIcon.Error && !String.IsNullOrEmpty(MsgBox_ErrorHeader) && !_ShowFatal)
                    msg = MsgBox_ErrorHeader + msg;
                else if (icon == MessageBoxIcon.Exclamation && !String.IsNullOrEmpty(MsgBox_WarningHeader))
                    msg = MsgBox_WarningHeader + msg;
                else if (icon == MessageBoxIcon.Information && !String.IsNullOrEmpty(MsgBox_InfoHeader))
                    msg = MsgBox_InfoHeader + msg;
            }
            #endregion

            #region Footer Action
            if (ShowFooter)
            {
                if (icon == MessageBoxIcon.Error && !String.IsNullOrEmpty(MsgBox_FatalErrorFooter) && _ShowFatal)
                    msg = msg + MsgBox_FatalErrorFooter;
                else if (icon == MessageBoxIcon.Error && !String.IsNullOrEmpty(MsgBox_ErrorFooter) && !_ShowFatal)
                    msg = msg + MsgBox_ErrorFooter;
                else if (icon == MessageBoxIcon.Exclamation && !String.IsNullOrEmpty(MsgBox_WarningFooter))
                    msg = msg + MsgBox_WarningFooter;
                else if (icon == MessageBoxIcon.Information && !String.IsNullOrEmpty(MsgBox_InfoFooter))
                    msg = msg + MsgBox_InfoFooter;
            }
            #endregion

            #region Title Header
            if (ShowTitleHeader)
            {
                if (icon == MessageBoxIcon.Error && !String.IsNullOrEmpty(MsgBox_FatalErrorTitleHeader) && _ShowFatal)
                    title = MsgBox_FatalErrorTitleHeader + ((!String.IsNullOrEmpty(title)) ? (" (" + title + ")") : "");
                else if (icon == MessageBoxIcon.Error && !String.IsNullOrEmpty(MsgBox_ErrorTitleHeader) && !_ShowFatal)
                    title = MsgBox_ErrorTitleHeader + ((!String.IsNullOrEmpty(title)) ? (" (" + title + ")") : "");
                else if (icon == MessageBoxIcon.Exclamation && !String.IsNullOrEmpty(MsgBox_WarningTitleHeader))
                    title = MsgBox_WarningTitleHeader + ((!String.IsNullOrEmpty(title)) ? (" (" + title + ")") : "");
                else if (icon == MessageBoxIcon.Information && !String.IsNullOrEmpty(MsgBox_InfoTitleHeader))
                    title = MsgBox_InfoTitleHeader + ((!String.IsNullOrEmpty(title)) ? (" (" + title + ")") : "");
            }
            #endregion

            #region Text Padding

            // Stripe last \n, if exists
            if (!String.IsNullOrEmpty(msg) && (msg.Length > 0) && (msg[msg.Length - 1] == '\n'))
                msg = msg.Remove(msg.Length - 1);

            // Make sure the text looks good, by using padding
            if (!String.IsNullOrEmpty(msg) && (msg.Length > 0) && (msg.Length < MaxNumberOfCharactersPerLine))
            {
                string[] lines = msg.Split('\n');
                StringBuilder sb = new StringBuilder();
                foreach (string line in lines)
                {
                    sb.Append(line.PadRight((int)MaxNumberOfCharactersPerLine));
                    sb.Append("\n");
                }
                msg = sb.ToString();
            }
            else if (!String.IsNullOrEmpty(msg) && (msg.Length > 0) && (msg.Length > MaxNumberOfCharactersPerLine))
            {
                // Incredible and amazing Padding code                
                string[] lines = msg.Split('\n');
                StringBuilder sb = new StringBuilder();
                for (int i = 0; i < lines.Length; ++i)
                {
                    if (lines[i].Length < MaxNumberOfCharactersPerLine)
                    {
                        sb.Append(lines[i].PadRight((int)MaxNumberOfCharactersPerLine));
                        sb.Append("\n");
                    }
                    else if (lines[i].Length > MaxNumberOfCharactersPerLine)
                    {
                        // truncate
                        for (int j = 0; j < lines[i].Length; j = j + (int)MaxNumberOfCharactersPerLine)
                        {
                            string strSub = lines[i].Substring(j, ((lines[i].Length - j) > (int)MaxNumberOfCharactersPerLine) ? (int)MaxNumberOfCharactersPerLine : (lines[i].Length - j));
                            if (strSub.Length == (int)MaxNumberOfCharactersPerLine)
                            {
                                sb.Append(strSub);
                                sb.Append("\n");
                            }
                            else
                            {
                                sb.Append(strSub.PadRight((int)MaxNumberOfCharactersPerLine));
                                sb.Append("\n");
                            }
                        }
                    }
                    else
                    {
                        sb.Append(lines[i]);
                        sb.Append("\n");
                    }
                }

                // Write nicely formatted Message out
                msg = sb.ToString();
            }
            else
            {
                // do nothing, string is miracioulsy exactly correct
            }
            #endregion

            // Remember the title & message that we'll look for.
            // The hook sees *all* windows, so we need to make sure we operate on the right one.            
            _msg = msg;
            _title = title;

            // if Owner is the Desktop Window
            _IsDesktopOwner = (owner.Handle == Functions.GetDestopWindow().Handle);

            // Icon could not be present
            if (TitleBarIcon != null)
                _hIcon = TitleBarIcon.ToBitmap().GetHicon();

            // Set the hook.
            // Suppress "GetCurrentThreadId() is deprecated" warning. 
            // It's documented that Thread.ManagedThreadId doesn't work with SetWindowsHookEx()
#pragma warning disable 0618
            _hHook = User32.SetWindowsHookEx(Definitions.WH_CBT, _hookProcDelegate, IntPtr.Zero, AppDomain.GetCurrentThreadId());
#pragma warning restore 0618

            // Pop a standard MessageBox. The hook will center it.
            DialogResult rslt = DialogResult.None;
            if (_IsDesktopOwner)
                rslt = MessageBox.Show(_msg, _title, btns, icon);
            else
                rslt = MessageBox.Show(owner, _msg, _title, btns, icon);

            // Release hook, clean up (may have already occurred)
            Unhook();

            return rslt;
        }

        private static void Unhook()
        {
            User32.UnhookWindowsHookEx(_hHook);
            _hHook = 0;
            _hookProcDelegate = null;
            _msg = null;
            _title = null;
        }

        private static int HookCallback(int code, IntPtr wParam, IntPtr lParam)
        {
            int hHook = _hHook;	// Local copy for CallNextHookEx() JIC we release _hHook

            // Look for HCBT_ACTIVATE, *not* HCBT_CREATEWND:
            //   child controls haven't yet been created upon HCBT_CREATEWND.
            if (code == Definitions.HCBT_ACTIVATE)
            {
                string cls = Functions.GetWindowClassName(wParam);
                if (cls == "#32770")  // MessageBoxes are Dialog boxes
                {
                    string title = Functions.GetWindowText(wParam);
                    string msg = Functions.GetDlgItemText(wParam, 0xFFFF);	// -1 aka IDC_STATIC
                    if ((title == _title) && (msg == _msg))
                    {
                        // Only Center the Window, if the Owner is NOT the Desktop
                        if (!_IsDesktopOwner)
                            CenterWindowOnParent(wParam);

                        Unhook();  // Release hook - we've done what we needed

                        // Now we also want to set the Icon on the Dialog
                        if (_hIcon != IntPtr.Zero)
                        {
                            User32.SendMessage(wParam, (int)Definitions.WM.WM_SETICON, (IntPtr)1, _hIcon);
                            User32.SendMessage(wParam, (int)Definitions.WM.WM_SETICON, (IntPtr)0, _hIcon);
                        }
                    }
                }
            }
            return User32.CallNextHookEx(hHook, code, wParam, lParam);
        }

        // Boilerplate window-centering code.
        // Split out of HookCallback() for clarity.
        private static void CenterWindowOnParent(IntPtr hChildWnd)
        {
            // Get child (MessageBox) size
            Structures.RECT rcChild = new Structures.RECT();
            User32.GetWindowRect(hChildWnd, out rcChild);
            int cxChild = rcChild.right - rcChild.left;
            int cyChild = rcChild.bottom - rcChild.top;

            // Get parent (Form) size & location
            IntPtr hParent = User32.GetParent(hChildWnd);
            Structures.RECT rcParent = new Structures.RECT();
            User32.GetWindowRect(hParent, out rcParent);
            int cxParent = rcParent.right - rcParent.left;
            int cyParent = rcParent.bottom - rcParent.top;

            // Center the MessageBox on the Form
            int x = rcParent.left + (cxParent - cxChild) / 2;
            int y = rcParent.top + (cyParent - cyChild) / 2;
            uint uFlags = 0x15;	// SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE;
            User32.SetWindowPos(hChildWnd, IntPtr.Zero, x, y, 0, 0, uFlags);
        }

        #endregion
    }
}