using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace Test_SearchAndFind
{
    public partial class Form1 : Form
    {
        #region Version und Copyright
        // Version und Copyright
        string programName = Path.GetFileNameWithoutExtension(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase); //Den Programmnamen auslesen
        string programVersion = System.Reflection.Assembly.GetExecutingAssembly().GetName().Version.ToString();
        static object[] attributes = Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(AssemblyCopyrightAttribute), false);
        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 = ((AssemblyCopyrightAttribute)attributes[0]).Copyright;
            return startYear.Remove(0, startYear.LastIndexOf(" ") + 1);
        }

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

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

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

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

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

        private void SetProgramInfo()
        {
            //Name, Version und Copyright setzen
            ProgramName = programName;
            ProgramVersion = programVersion;
            Copyright = copyright;
        }
        #endregion
        public Form1()
        {
            SetProgramInfo();
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            this.Text = String.Concat("Test_Search, Find and Replace     -     Version: ", ProgramVersion, "  -  ", Copyright, " by E. Höglinger");
            textBoxText.Focus();
            textBoxText.Select(0, 0);

            //textBoxSearchstring.Focus();
            //textBoxSearchstring.Text = "";
            this.ActiveControl = textBoxSearchstring;
        }

        List<int> AllPositions = new List<int>();
        int SelectedPosition { set; get; }

        private List<int> Positions(string myText, string searchText)
        {
            List<int> pos = new List<int>();

            if (String.IsNullOrEmpty(myText) || String.IsNullOrEmpty(searchText))
            {
                return pos;
            }

            int tempPos = 0;
            int currentPos = 0;

            while (myText.Contains(searchText))
            {
                if (checkBoxFullword.Checked)
                {
                    //Nur ganzes Wort suchen
                    currentPos = IndexOfWord(myText, searchText);
                }
                else
                {
                    //Suchstring suchen
                    currentPos = myText.IndexOf(searchText);
                }

                tempPos += currentPos;
                pos.Add(tempPos);
                tempPos += searchText.Length;

                myText = myText.Remove(0, currentPos + searchText.Length);

                if (currentPos == -1)
                {
                    break;
                }
            }

            return pos;
        }

        private Regex myRegex;

        public int IndexOfWord(string myString, string myWord)
        {
            myRegex = new Regex("\\b" + Regex.Escape(myWord) + "\\b", RegexOptions.Compiled);

            Match mtch = myRegex.Match(myString);

            if (mtch.Success)
                return mtch.Index;
            else
                return -1;
        }

        private void Search()
        {
            AllPositions.Clear();

            string fullText = textBoxText.Text;
            string searchText = textBoxSearchstring.Text;
            
            if (checkBoxCase.Checked)
            {
                //Groß-/Kleinschreibung ignorieren
                fullText = fullText.ToLower();
                searchText = searchText.ToLower();
            }

            if (!String.IsNullOrEmpty(searchText) && fullText.Contains(searchText))
            {
                AllPositions = Positions(fullText, searchText);

                SelectedPosition = 0;

                if (AllPositions[SelectedPosition] != -1)
                {
                    SelectSearchString(AllPositions[SelectedPosition], searchText.Length);
                }
                else
                {
                    MessageBox.Show("Es wurde kein (weiterer) Suchtext gefunden");
                }
            }
            else
            {
                MessageBox.Show("Es wurde kein (weiterer) Suchtext gefunden");
            }
        }

        private void Previous()
        {
            if (!String.IsNullOrEmpty(textBoxSearchstring.Text))
            {
                if (AllPositions.Count == 0)
                {
                    Search();
                    if (textBoxText.Text.Contains(textBoxSearchstring.Text))
                    {
                        Previous(); //Den letzten gefundenen Suchstring selektieren
                    }
                }
                else if (SelectedPosition > 0)
                {
                    //Position um eins verringern und Suchstring im Text selektieren
                    SelectedPosition--;
                    SelectSearchString(AllPositions[SelectedPosition], textBoxSearchstring.Text.Length);
                }
                else
                {
                    //Selected Position auf die letzte Position setzten und Suchstring im Text selektieren
                    SelectedPosition = AllPositions.Count - 1;
                    SelectSearchString(AllPositions[SelectedPosition], textBoxSearchstring.Text.Length);
                }
            }
        }

        private void Next()
        {
            if (!String.IsNullOrEmpty(textBoxSearchstring.Text))
            {
                if (AllPositions.Count == 0)
                {
                    Search();
                }
                else if (SelectedPosition + 1 < AllPositions.Count)
                {
                    //Position um eins erhöhen und Suchstring im Text selektieren
                    SelectedPosition++;
                    SelectSearchString(AllPositions[SelectedPosition], textBoxSearchstring.Text.Length);
                }
                else
                {
                    //Selected Position auf 0 setzten und Suchstring im Text selektieren
                    SelectedPosition = 0;
                    SelectSearchString(AllPositions[SelectedPosition], textBoxSearchstring.Text.Length);
                }
            }
        }

        private int Replace()
        {
            if (AllPositions[SelectedPosition] != -1)
            {
                textBoxText.Text = textBoxText.Text.Remove(AllPositions[SelectedPosition], textBoxSearchstring.Text.Length);
                textBoxText.Text = textBoxText.Text.Insert(AllPositions[SelectedPosition], textBoxReplaceText.Text);
                textBoxText.Refresh();
                Search(); //Neu durchsuchen, damit die Starindexes wieder passen
                return 0; //Ende noch nicht erreicht
            }
            else
            {
                return -1; //Ende erreicht
            }
        }

        private void ReplaceAll()
        {
            string fullText = textBoxText.Text;
            string searchText = textBoxSearchstring.Text;

            if (checkBoxCase.Checked)
            {
                //Groß-/Kleinschreibung ignorieren
                fullText = fullText.ToLower();
                searchText = searchText.ToLower();
            }

            int nextRun = 0;

            while (fullText.Contains(searchText) && nextRun != -1)
            {
                nextRun = Replace();
                fullText = textBoxText.Text;

                if (checkBoxCase.Checked)
                {
                    //Groß-/Kleinschreibung ignorieren
                    fullText = fullText.ToLower();
                }
            }

            textBoxReplaceText.Focus();
        }

        private void SelectSearchString(int position, int length)
        {
            if (position != -1)
            {
                textBoxText.Focus();
                textBoxText.Select(position, length);
                textBoxText.Refresh();
            }
        }

        private void textBoxSearchstring_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                Search();


                //TODO: Test
                var suche = new Search(textBoxText.Text, textBoxSearchstring.Text, checkBoxCase.Checked, checkBoxFullword.Checked);
                string pos = "Es wurden " + suche.AllPositions.Count + " Übereinstimmungen\r\nan diesen Positionen gefunden:";
                foreach (var item in suche.AllPositions)
                {
                    pos = String.Concat(pos, "\r\n", item);
                }
                pos = String.Concat(pos, "\r\nAktuelle Cursor Position: ", suche.CurrentCursorPosition, "\r\nEs ist ein Fehler passiert: ", suche.Error.ToString());
                MessageBox.Show(pos);
                for (int i = 0; i < 6; i++)
                {
                    suche.NextPosition();
                    MessageBox.Show(pos + "\r\n\r\nIndex erhöhen\r\nIndex: " + suche.Index + "\r\nCursorposition: " + suche.CurrentCursorPosition);
                }
                for (int i = 0; i < 8; i++)
                {
                    suche.PreviousPosition();
                    MessageBox.Show(pos + "\r\n\r\nIndex veringern\r\nIndex: " + suche.Index + "\r\nCursorposition: " + suche.CurrentCursorPosition);
                }
            }
        }

        private void textBoxSearchstring_TextChanged(object sender, EventArgs e)
        {
            AllPositions.Clear();
        }

        private void checkBoxCase_CheckedChanged(object sender, EventArgs e)
        {
            if (!String.IsNullOrEmpty(textBoxSearchstring.Text))
            {
                Search();
            }
        }

        private void checkBoxFullword_CheckedChanged(object sender, EventArgs e)
        {
            if (!String.IsNullOrEmpty(textBoxSearchstring.Text))
            {
                Search();
            }
        }

        private void buttonPrevious_Click(object sender, EventArgs e)
        {
            Previous();
        }

        private void buttonNext_Click(object sender, EventArgs e)
        {
            Next();
        }

        private void textBoxReplaceText_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                textBoxText.Focus();
            }
        }

        private void buttonReplace_Click(object sender, EventArgs e)
        {
            Replace();
        }

        private void buttonReplaceAll_Click(object sender, EventArgs e)
        {
            ReplaceAll();
        }
    }
}