using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Linq;
using System.Windows.Forms;

using BizHawk.Client.EmuHawk.CustomControls;

namespace BizHawk.Client.EmuHawk
{
	public class InputRoll : Control
	{
		private readonly GDIRenderer Gdi;
		private readonly RollColumns Columns = new RollColumns();

		private bool NeedToReDrawColumn = false;
		private int _horizontalOrientedColumnWidth = 0;
		private Size _charSize;

		public InputRoll()
		{
			CellPadding = 3;
			CurrentCell = null;
			Font = new Font("Courier New", 8);  // Only support fixed width

			SetStyle(ControlStyles.AllPaintingInWmPaint, true);
			SetStyle(ControlStyles.UserPaint, true);
			SetStyle(ControlStyles.SupportsTransparentBackColor, true);
			SetStyle(ControlStyles.Opaque, true);

			Gdi = new GDIRenderer();

			using (var g = CreateGraphics())
			using (var LCK = Gdi.LockGraphics(g))
			{
				_charSize = Gdi.MeasureString("A", this.Font);
			}
		}

		protected override void Dispose(bool disposing)
		{
			Gdi.Dispose();
			base.Dispose(disposing);
		}

		#region Properties

		/// <summary>
		/// Gets or sets the amount of padding on the text inside a cell
		/// </summary>
		[DefaultValue(3)]
		[Category("Behavior")]
		public int CellPadding { get; set; }

		// TODO: remove this, it is put here for more convenient replacing of a virtuallistview in tools with the need to refactor code
		public bool VirtualMode { get; set; }

		/// <summary>
		/// Gets or sets whether the control is horizontal or vertical
		/// </summary>
		[Category("Behavior")]
		public bool HorizontalOrientation { get; set; }

		/// <summary>
		/// Gets or sets the sets the virtual number of items to be displayed.
		/// </summary>
		[Category("Behavior")]
		public int ItemCount { get; set; }

		/// <summary>
		/// Gets or sets the sets the columns can be resized
		/// </summary>
		[Category("Behavior")]
		public bool AllowColumnResize { get; set; }

		/// <summary>
		/// Gets or sets the sets the columns can be reordered
		/// </summary>
		[Category("Behavior")]
		public bool AllowColumnReorder { get; set; }

		#endregion

		#region Event Handlers

		/// <summary>
		/// Fire the QueryItemText event which requests the text for the passed Listview cell.
		/// </summary>
		[Category("Virtual")]
		public event QueryItemTextHandler QueryItemText;

		/// <summary>
		/// Fire the QueryItemBkColor event which requests the background color for the passed Listview cell
		/// </summary>
		[Category("Virtual")]
		public event QueryItemBkColorHandler QueryItemBkColor;

		/// <summary>
		/// Fires when the mouse moves from one cell to another (including column header cells)
		/// </summary>
		[Category("Mouse")]
		public event CellChangeEventHandler PointedCellChanged;

		/// <summary>
		/// Retrieve the text for a cell
		/// </summary>
		public delegate void QueryItemTextHandler(int index, int column, out string text);

		/// <summary>
		/// Retrieve the background color for a cell
		/// </summary>
		public delegate void QueryItemBkColorHandler(int index, int column, ref Color color);

		public delegate void CellChangeEventHandler(object sender, CellEventArgs e);

		public class CellEventArgs
		{
			public CellEventArgs(Cell oldCell, Cell newCell)
			{
				OldCell = oldCell;
				NewCell = newCell;
			}

			public Cell OldCell { get; private set; }
			public Cell NewCell { get; private set; }
		}

		#endregion

		#region Public Methods

		// TODO: designer ignore
		public Cell CurrentCell { get; set; }

		public string UserSettingsSerialized()
		{
			return string.Empty; // TODO
		}

		public void AddColumns(IEnumerable<RollColumn> columns)
		{
			Columns.AddRange(columns);
			ColumnChanged();
		}

		public void AddColumn(RollColumn column)
		{
			Columns.Add(column);
			ColumnChanged();
		}

		#endregion

		#region Paint

		protected override void OnPaint(PaintEventArgs e)
		{
			using (var LCK = Gdi.LockGraphics(e.Graphics))
			{
				// Header
				if (Columns.Any())
				{
					DrawColumnBg(e);
					DrawColumnText(e);
				}

				// Background
				DrawBg(e);

				// ForeGround
				DrawData(e);
			}
		}

		protected override void OnPaintBackground(PaintEventArgs pevent)
		{
			// Do nothing, and this should never be called
		}

		private void DrawColumnText(PaintEventArgs e)
		{
			if (HorizontalOrientation)
			{
				int start = 0;
				Gdi.PrepDrawString(this.Font, this.ForeColor);
				foreach (var column in Columns)
				{
					var point = new Point(CellPadding, start + CellPadding);
					Gdi.DrawString(column.Text, point);
					start += CellHeight;
				}
			}
			else
			{
				int start = CellPadding;
				Gdi.PrepDrawString(this.Font, this.ForeColor);
				foreach (var column in Columns)
				{
					var point = new Point(start + CellPadding, CellPadding);
					Gdi.DrawString(column.Text, point);
					start += CalcWidth(column);
				}
			}
		}

		private void DrawData(PaintEventArgs e)
		{
			if (QueryItemText != null)
			{
				if (HorizontalOrientation)
				{
					var visibleRows = (Width - _horizontalOrientedColumnWidth) / CellWidth;
					Gdi.PrepDrawString(this.Font, this.ForeColor);
					for (int i = 0; i < visibleRows; i++)
					{
						for (int j = 0; j < Columns.Count; j++)
						{
							string text;
							int x = _horizontalOrientedColumnWidth + CellPadding + (CellWidth * i);
							int y = j * CellHeight;
							var point = new Point(x, y);
							QueryItemText(i, j, out text);
							Gdi.DrawString(text, point);
						}
					}
				}
				else
				{
					var visibleRows = (Height / CellHeight) - 1;
					Gdi.PrepDrawString(this.Font, this.ForeColor);
					for (int i = 1; i < visibleRows; i++)
					{
						int x = 1;
						for (int j = 0; j < Columns.Count; j++)
						{
							string text;
							var point = new Point(x + CellPadding, i * CellHeight);
							QueryItemText(i, j, out text);
							Gdi.DrawString(text, point);
							x += CalcWidth(Columns[j]);
						}
					}
				}
			}
		}

		private void DrawColumnBg(PaintEventArgs e)
		{
			Gdi.SetBrush(SystemColors.ControlLight);
			Gdi.SetSolidPen(Color.Black);

			if (HorizontalOrientation)
			{
				Gdi.DrawRectangle(0, 0, _horizontalOrientedColumnWidth, Height);
				Gdi.FillRectangle(1, 1, _horizontalOrientedColumnWidth - 3, Height - 3);

				int start = 0;
				foreach (var column in Columns)
				{
					start += CellHeight;
					Gdi.Line(1, start, _horizontalOrientedColumnWidth - 1, start);
				}
			}
			else
			{
				Gdi.DrawRectangle(0, 0, Width, CellHeight);
				Gdi.FillRectangle(1, 1, Width - 3, CellHeight - 3);

				int start = 0;
				foreach (var column in Columns)
				{
					start += CalcWidth(column);
					Gdi.Line(start, 0, start, CellHeight);
				}
			}
		}

		private void DrawBg(PaintEventArgs e)
		{
			var startPoint = StartBg();

			Gdi.SetBrush(Color.White);
			Gdi.SetSolidPen(Color.Black);

			Gdi.DrawRectangle(startPoint.X, startPoint.Y, Width, Height);

			Gdi.SetSolidPen(SystemColors.ControlLight);
			if (HorizontalOrientation)
			{
				// Columns
				for (int i = 1; i < Width / CellWidth; i++)
				{
					var x = _horizontalOrientedColumnWidth + (i * CellWidth);
					Gdi.Line(x, 1, x, Columns.Count * CellHeight);
				}

				// Rows
				for (int i = 1; i < Columns.Count + 1; i++)
				{
					Gdi.Line(_horizontalOrientedColumnWidth, i * CellHeight, Width - 2, i * CellHeight);
				}
			}
			else
			{
				// Columns
				int x = 0;
				int y = CellHeight;
				foreach (var column in Columns)
				{
					x += CalcWidth(column);
					Gdi.Line(x, y, x, Height - 1);
				}

				// Rows
				for (int i = 2; i < Height / CellHeight; i++)
				{
					Gdi.Line(1, (i * CellHeight) + 1, Width - 2, (i * CellHeight) + 1);
				}
			}
		}

		#endregion

		#region Mouse and Key Events

		protected override void OnKeyDown(KeyEventArgs e)
		{
			if (e.Control && !e.Alt && !e.Shift && e.KeyCode == Keys.R) // Ctrl + R
			{
				HorizontalOrientation ^= true;
				Refresh();
			}

			base.OnKeyDown(e);
		}

		protected override void OnMouseMove(MouseEventArgs e)
		{
			CalculatePointedCell(e.X, e.Y);
			base.OnMouseMove(e);
		}

		protected override void OnMouseEnter(EventArgs e)
		{
			CurrentCell = new Cell
			{
				Column = null,
				RowIndex = null
			};

			base.OnMouseEnter(e);
		}

		protected override void OnMouseLeave(EventArgs e)
		{
			CurrentCell = null;
			base.OnMouseLeave(e);
		}

		#endregion

		#region Helpers

		private void CalculatePointedCell(int x, int y)
		{
			var newCell = new Cell();

			// If pointing to a column header
			if (Columns.Any())
			{
				if (HorizontalOrientation)
				{
					if (x < _horizontalOrientedColumnWidth)
					{
						newCell.RowIndex = null;
					}
					else
					{
						newCell.RowIndex = (x - _horizontalOrientedColumnWidth) / CellWidth;
					}

					int colIndex = (y / CellHeight);
					if (colIndex >= 0 && colIndex < Columns.Count)
					{
						newCell.Column = Columns[colIndex];
					}
				}
				else
				{
					if (y < CellHeight)
					{
						newCell.RowIndex = null;
					}
					else
					{
						newCell.RowIndex = (y / CellHeight) - 1;
					}

					int start = 0;
					//for (int i = 0; i < Columns.Count; i++)
					foreach (var column in Columns)
					{
						if (x > start)
						{
							start += CalcWidth(column);
							if (x <= start)
							{
								newCell.Column = column;
								break;
							}
						}
					}
				}
			}

			if (!newCell.Equals(CurrentCell))
			{
				CellChanged(CurrentCell, newCell);
				CurrentCell = newCell;
			}
		}

		private void CellChanged(Cell oldCell, Cell newCell)
		{
			if (PointedCellChanged != null)
			{
				PointedCellChanged(this, new CellEventArgs(oldCell, newCell));
			}
		}

		private bool NeedToUpdateScrollbar()
		{
			return true;
		}

		// TODO: Calculate this on Orientation change instead of call it every time
		private Point StartBg()
		{
			if (Columns.Any())
			{
				if (HorizontalOrientation)
				{
					var x = _horizontalOrientedColumnWidth - 1;
					var y = 0;
					return new Point(x, y);
				}
				else
				{
					var y = CellHeight - 1;
					return new Point(0, y);
				}
			}

			return new Point(0, 0);
		}

		// TODO: calculate this on Cell Padding change instead of calculate it every time
		private int CellHeight
		{
			get
			{
				return _charSize.Height + (CellPadding * 2);
			}
		}

		// TODO: calculate this on Cell Padding change instead of calculate it every time
		private int CellWidth
		{
			get
			{
				return _charSize.Width + (CellPadding * 4); // Double the padding for horizontal because it looks better
			}
		}

		private bool NeedsScrollbar
		{
			get
			{
				if (HorizontalOrientation)
				{
					return Width / CellWidth > ItemCount;
				}

				return Height / CellHeight > ItemCount;
			}
		}

		private void ColumnChanged()
		{
			NeedToReDrawColumn = true;
			var text = Columns.Max(c => c.Text.Length);
			_horizontalOrientedColumnWidth = (text * _charSize.Width) + (CellPadding * 2);
		}

		// On Column Change calculate this for every column
		private int CalcWidth(RollColumn col)
		{
			return col.Width ?? ((col.Text.Length * _charSize.Width) + (CellPadding * 4));
		}

		#endregion
	}

	public class RollColumns : List<RollColumn>
	{
		public void Add(string name, string text, int width, RollColumn.InputType type = RollColumn.InputType.Text)
		{
			Add(new RollColumn
			{
				Name = name,
				Text = text,
				Width = width,
				Type = type
			});
		}

		public IEnumerable<string> Groups
		{
			get
			{
				return this
					.Select(x => x.Group)
					.Distinct();
			}
		}
	}

	public class RollColumn
	{
		public enum InputType { Boolean, Float, Text, Image }

		public string Group { get; set; }
		public int? Width { get; set; }
		public string Name { get; set; }
		public string Text { get; set; }
		public InputType Type { get; set; }
	}

	public class Cell
	{
		public RollColumn Column { get; set; }
		public int? RowIndex { get; set; }

		public Cell() { }

		public Cell(Cell cell)
		{
			Column = cell.Column;
			RowIndex = cell.RowIndex;
		}

		public override bool Equals(object obj)
		{
			if (obj is Cell)
			{
				var cell = obj as Cell;
				return this.Column == cell.Column && this.RowIndex == cell.RowIndex;
			}
			
			return base.Equals(obj);
		}

		public override int GetHashCode()
		{
			return Column.GetHashCode() + RowIndex.GetHashCode();
		}
	}
}