using Eugen.ESystem.Windows.Forms;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using DisplLanguage = Eugen.ESystem.Windows.Forms.Languages.Language;

namespace Eugen.ESystem
{
    /// <summary>
    /// Opens the help file in the given language.
    /// </summary>
    public class OpenHelpFile
    {
        #region Version und Copyright
        // Version und Copyright
        static string dllName = Path.GetFileNameWithoutExtension(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase); //Den Programmnamen auslesen
        static string dllVersion = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version.ToString();
        static object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyCopyrightAttribute), false);
        static string copyright = GenerateCopyright();
        string icon = Application.StartupPath + "\\Info.bmp";
        //Assembly Datum und Zeit
        static DateTime value = AssemblyDateTime();
        string date = value.ToShortDateString();
        string time = value.ToLongTimeString();
        private static DateTime AssemblyDateTime()
        {
            var version = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version;
            var buildDateTime = new DateTime(2000, 1, 1).Add(new TimeSpan(TimeSpan.TicksPerDay * version.Build + TimeSpan.TicksPerSecond * 2 * version.Revision));
            //Tage seit dem 1. Januar 2000 und Sekunden seit Mitternacht, (multiplizier mit 2 ergibt das Original)
            return buildDateTime;
        }

        private static string CurrentYear()
        {
            DateTime dtn = DateTime.Now;
            return dtn.Year.ToString();
        }

        private static string StartYear()
        {
            string startYear = "";
            if (((AssemblyCopyrightAttribute)attributes[0]).Copyright.Contains("Copyright © "))
            {
                startYear = ((AssemblyCopyrightAttribute)attributes[0]).Copyright.Replace("Copyright © ", "");
                while (startYear.StartsWith(" "))
                {
                    startYear = startYear.Remove(0, 1);
                }
                startYear = startYear.Remove(startYear.IndexOf(" "));
                return startYear;
            }
            else
            {
                DateTime dtn = DateTime.Now;
                return dtn.Year.ToString();
            }
        }

        private static string GenerateCopyright()
        {
            string startYear = StartYear();
            string currentYear = CurrentYear();

            if (startYear == currentYear)
            {
                return ((AssemblyCopyrightAttribute)attributes[0]).Copyright;
            }
            else
            {
                return ((AssemblyCopyrightAttribute)attributes[0]).Copyright.Replace(startYear, String.Concat(startYear, "-", currentYear));
            }
        }
        #endregion

        #region DLL-Info
        /// <summary>
        /// Contains the name of the program file
        /// </summary>
        public static string DllName { set; get; }

        /// <summary>
        /// Contains the version of the program file
        /// </summary>
        public static string DllVersion { set; get; }

        /// <summary>
        /// Contains the copyright notice
        /// </summary>
        public static string Copyright { set; get; }

        private static void SetDllInfo()
        {
            //Name, Version und Copyright setzen
            DllName = dllName;
            DllVersion = dllVersion;
            Copyright = copyright;
        }
        #endregion

        /// <summary>
		/// Opens the help file in the given language.
		/// </summary>
        static OpenHelpFile()
        {
            SetDllInfo();
        }

        /// <summary>
        /// Opens the help file in the desired language
        /// </summary>
        /// <param name="language">A valid language. E.G.:'german' or 'english'</param>
        public static void Open(string language)
        {
            //Systemsprache aus alle möglichen Sprachen ermitteln
            DisplLanguage dispLanguage = DisplLanguage.German;
            foreach (var e in Enum.GetValues(typeof(DisplLanguage)))
            {
                if (language.ToLower() == e.ToString().ToLower())
                {
                    dispLanguage = (Languages.Language)e;
                }
            }

            //Prüfen ob die Hilfe schon läuft. Wenn nicht dann aufrufen
            if (!CheckIfRun())
            {
                //Hilfedatei setzen
                string helpFile = SetHelpFile(dispLanguage);

                //Hilfedatei ins Temp-Verzeichnis kopieren, damit der Inhalt von Windows angezeigt wird
                helpFile = CopyHelpFileToTemp(helpFile);

                //Hilfedatei aufrufen
                ShowHelpFile(helpFile);
            }
        }

        private static bool CheckIfRun()
        {
            string program = "hh";
            bool run = false;

            Process[] ProgrammTask = Process.GetProcesses();
            foreach (Process ScannTask in ProgrammTask)
            {
                if (ScannTask.ProcessName == program)
                {
                    run = true;
                }
            }

            return run;
        }

        private static string SetHelpFile(DisplLanguage dispLanguage)
        {
            string helpFile = "";

            switch (dispLanguage.ToString())
            {
                case "German":
                    helpFile = String.Concat(Application.StartupPath, "\\Hilfe.chm");
                    break;
                case "English":
                    helpFile = String.Concat(Application.StartupPath, "\\Help.chm");
                    break;
                case "French":
                    helpFile = String.Concat(Application.StartupPath, "\\Aide.chm");
                    break;
                case "Italian":
                    helpFile = String.Concat(Application.StartupPath, "\\Aiuto.chm");
                    break;
                case "Spanish":
                    helpFile = String.Concat(Application.StartupPath, "\\Ayuda.chm");
                    break;
                case "Portuguese":
                    helpFile = String.Concat(Application.StartupPath, "\\Ajuda.chm");
                    break;
                case "Finska":
                    helpFile = String.Concat(Application.StartupPath, "\\Auta.chm");
                    break;
                case "Swedish":
                    helpFile = String.Concat(Application.StartupPath, "\\Hjälp.chm");
                    break;
                case "Czech":
                    helpFile = String.Concat(Application.StartupPath, "\\Pomoc.chm");
                    break;
                case "Slovak":
                    helpFile = String.Concat(Application.StartupPath, "\\Pomoc.chm");
                    break;
                case "Slovenian":
                    helpFile = String.Concat(Application.StartupPath, "\\Pomoč.chm");
                    break;
                case "Polish":
                    helpFile = String.Concat(Application.StartupPath, "\\Pomoc_.chm");
                    break;
                case "Bulgarian":
                    helpFile = String.Concat(Application.StartupPath, "\\Помогне.chm");
                    break;
                case "Romanian":
                    helpFile = String.Concat(Application.StartupPath, "\\Ajutor.chm");
                    break;
                case "Hungarian":
                    helpFile = String.Concat(Application.StartupPath, "\\Segítség.chm");
                    break;
                case "Russian":
                    helpFile = String.Concat(Application.StartupPath, "\\Помощь.chm");
                    break;
                case "Japanese":
                    helpFile = String.Concat(Application.StartupPath, "\\ヘルプ.chm");
                    break;
                case "Chinese":
                    helpFile = String.Concat(Application.StartupPath, "\\帮忙.chm");
                    break;
                default:
                    break;
            }     

            return helpFile;
        }

        private static string CopyHelpFileToTemp(string helpfile)
        {
            string file = Path.GetFileName(helpfile);
            string tempHelpFile = String.Concat("C:\\Temp\\", file);

            try
            {
                //Vorhandene Datei löschen
                if (File.Exists(tempHelpFile))
                {
                    File.Delete(tempHelpFile);
                }

                //Hilfedatei in Temp-Verzeichnis kopieren
                if (!Directory.Exists("C:\\Temp"))
                {
                    Directory.CreateDirectory("C:\\Temp");
                }

                File.Copy(helpfile, tempHelpFile);

                //Wenn das Kopieren erfolgreich war, die Datei mit neuem Pfad zurückgeben
                if (File.Exists(tempHelpFile))
                {
                    return tempHelpFile; //Wenn die Datei existiert, dann die temporäre Hilfedatei zurückgeben
                }
                else
                {
                    return helpfile; //Wenn die Datei nicht existiert, dann die ursprüngliche Hilfedatei zurückgeben
                }
            }
            catch
            {
                return helpfile; //Wenn ein Fehler passiert ist, dann die ursprüngliche Hilfedatei zurückgeben
            }
        }

        private static void ShowHelpFile(string helpFile)
        {
            if (!File.Exists(helpFile))
            {
                throw new FileNotFoundException(helpFile);
            }

            try
            {
                Process.Start(helpFile);
            }
            catch (CannotShowHelpFileException)
            {
                throw new CannotShowHelpFileException(helpFile);
            }
        }
    }

    #region Exception
    public class CannotShowHelpFileException : ApplicationException
    {
        public CannotShowHelpFileException()
        { }

        public CannotShowHelpFileException(string message) : base(message)
        { }

        public CannotShowHelpFileException(string message, Exception inner) : base(message, inner)
        { }
    }
    #endregion
}