using System;
using System.Windows.Forms;
using System.Text.RegularExpressions;
using System.Collections.Generic;

namespace UyghurEditPP
{
	public partial class ReplaceForm : Form
	{
		TextEditor tb;
		bool firstSearch = true;
		public ReplaceForm(TextEditor tb)
		{
			InitializeComponent();
			this.tb = tb;
		}

		private void btClose_Click(object sender, EventArgs e)
		{
			Close();
		}

		private void btFindNext_Click(object sender, EventArgs e)
		{
			try
			{
				if (!Find(tbFind.Text))
					MessageBox.Show("Not found");
			}
			catch (Exception ex)
			{
				MessageBox.Show(ex.Message);
			}
		}

		public List<Range> FindAll(string pattern)
		{
			var opt = cbMatchCase.Checked ? RegexOptions.None : RegexOptions.IgnoreCase;
			if (!cbRegex.Checked)
				pattern = Regex.Escape(pattern);
			if (cbWholeWord.Checked)
				pattern = "\\b" + pattern + "\\b";
			//
			var range = tb.Selection.IsEmpty? tb.Range.Clone() : tb.Selection.Clone();
			//
			var list = new List<Range>();
			foreach (var r in range.GetRangesByLines(pattern, opt))
				list.Add(r);

			return list;
		}

		public bool Find(string pattern)
		{
			RegexOptions opt = cbMatchCase.Checked ? RegexOptions.None : RegexOptions.IgnoreCase;
			if (!cbRegex.Checked)
				pattern = Regex.Escape(pattern);
			if (cbWholeWord.Checked)
				pattern = "\\b" + pattern + "\\b";
			//
			Range range = tb.Selection.Clone();
			range.Normalize();
			//
			if (firstSearch)
			{
				startPlace = range.Start;
				firstSearch = false;
			}
			//
			range.Start = range.End;
			if (range.Start >= startPlace)
				range.End = new Place(tb.GetLineLength(tb.LinesCount - 1), tb.LinesCount - 1);
			else
				range.End = startPlace;
			//
			foreach (var r in range.GetRangesByLines(pattern, opt))
			{
				tb.Selection.Start = r.Start;
				tb.Selection.End = r.End;
				tb.DoSelectionVisible();
				tb.Invalidate();
				return true;
			}
			if (range.Start >= startPlace && startPlace > Place.Empty)
			{
				tb.Selection.Start = new Place(0, 0);
				return Find(pattern);
			}
			return false;
		}

		private void tbFind_KeyPress(object sender, KeyPressEventArgs e)
		{
			if (e.KeyChar == '\r')
				btFindNext_Click(sender, null);
			if (e.KeyChar == '\x1b')
				Hide();
		}

		protected override bool ProcessCmdKey(ref Message msg, Keys keyData) // David
		{
			if (keyData == Keys.Escape)
			{
				this.Close();
				return true;
			}
			return base.ProcessCmdKey(ref msg, keyData);
		}

		private void ReplaceForm_FormClosing(object sender, FormClosingEventArgs e)
		{
			if (e.CloseReason == CloseReason.UserClosing)
			{
				e.Cancel = true;
				Hide();
			}
			this.tb.Focus();
		}

		private void btReplace_Click(object sender, EventArgs e)
		{
			try
			{
				if (tb.SelectionLength != 0){
					//tb.InsertText(tbReplace.Text);
				}
				btFindNext_Click(sender, null);
			}
			catch (Exception ex)
			{
				MessageBox.Show(ex.Message);
			}
		}

		private void btReplaceAll_Click(object sender, EventArgs e)
		{
			try
			{
				//tb.Selection.BeginUpdate();

				//search
				var ranges = FindAll(tbFind.Text);
				//check readonly
				var ro = false;
				foreach (var r in ranges)
					if (r.ReadOnly)
				{
					ro = true;
					break;
				}
				//replace
				if (!ro)
					if (ranges.Count > 0)
				{
					tb.TextSource.Manager.ExecuteCommand(new ReplaceTextCommand(tb.TextSource, ranges, tbReplace.Text));
					tb.Selection.Start = new Place(0, 0);
				}
				//
				tb.Invalidate();
				MessageBox.Show(ranges.Count + " occurrence(s) replaced");
			}
			catch (Exception ex)
			{
				MessageBox.Show(ex.Message);
			}
		}

		protected override void OnActivated(EventArgs e)
		{
			tbFind.Focus();
			ResetSearch();
		}

		void ResetSearch()
		{
			firstSearch = true;
		}

		private void cbMatchCase_CheckedChanged(object sender, EventArgs e)
		{
			ResetSearch();
		}
	}
}
