using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;

using JJC.Psharp.Lang;
using JJC.Psharp.Predicates;

namespace ox4 {
	/// <summary>
	/// P# demonstration program.
	/// 22 February 2002.
	/// 
	/// Web Application for a 4 x 4 noughts and crosses game.
	/// Each move can be taken by either the user or the computer.
	/// The computer's moves are chosen by a Prolog backend.
	/// </summary>

	public class Ox4Form : System.Web.UI.Page {

		protected System.Web.UI.WebControls.Button Cell1, Cell2, Cell3, Cell4, Cell5, 
			Cell6, Cell7, Cell8, Cell9, Cell10, Cell11, Cell12, Cell13, Cell14, Cell15, Cell16;
		protected System.Web.UI.WebControls.Button ResetButton, MoveButton;
		protected System.Web.UI.WebControls.Label Title;
		
		private bool winLock {
			get { return (bool)Session.Contents[ "winLock" ]; }
			set { Session.Contents[ "winLock" ] = value; }
		}

		private Term currentBoard {
			get { return (Term)Session.Contents[ "currentBoard" ]; }
			set { Session.Contents[ "currentBoard" ] = value; }
		}

		private SymbolTerm currentPlayer {
			get { return (SymbolTerm)Session.Contents[ "currentPlayer" ]; }
			set { Session.Contents[ "currentPlayer" ] = value;	}
		}

		private bool haveInited {
			get { return (bool)Session.Contents[ "haveInited" ]; }
			set { Session.Contents[ "haveInited" ] = value; }
		}

		protected System.Web.UI.WebControls.Button[] Cells;	


		private void Page_Load(object sender, System.EventArgs e) {
			Cells = new Button[] { Cell1, Cell2, Cell3, Cell4, Cell5, Cell6, Cell7, Cell8,
									 Cell9, Cell10, Cell11, Cell12, Cell13, Cell14, Cell15, Cell16 };
			if( !haveInited ) {
				haveInited = true;
				ResetBoard();
			}
		}

		#region Web Form Designer generated code
		override protected void OnInit(EventArgs e) {
			//
			// CODEGEN: This call is required by the ASP.NET Web Form Designer.
			//
			InitializeComponent();
			base.OnInit(e);
		}
		
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		private void InitializeComponent() {
			this.ResetButton.Click += new System.EventHandler(this.ResetButton_Click);
			this.Cell16.Click += new System.EventHandler(this.Cell16_Click);
			this.Cell15.Click += new System.EventHandler(this.Cell15_Click);
			this.Cell14.Click += new System.EventHandler(this.Cell14_Click);
			this.Cell13.Click += new System.EventHandler(this.Cell13_Click);
			this.Cell12.Click += new System.EventHandler(this.Cell12_Click);
			this.Cell11.Click += new System.EventHandler(this.Cell11_Click);
			this.Cell10.Click += new System.EventHandler(this.Cell10_Click);
			this.Cell9.Click += new System.EventHandler(this.Cell9_Click);
			this.Cell8.Click += new System.EventHandler(this.Cell8_Click);
			this.Cell7.Click += new System.EventHandler(this.Cell7_Click);
			this.Cell6.Click += new System.EventHandler(this.Cell6_Click);
			this.Cell5.Click += new System.EventHandler(this.Cell5_Click);
			this.Cell4.Click += new System.EventHandler(this.Cell4_Click);
			this.Cell3.Click += new System.EventHandler(this.Cell3_Click);
			this.Cell2.Click += new System.EventHandler(this.Cell2_Click);
			this.MoveButton.Click += new System.EventHandler(this.MoveButton_Click);
			this.Cell1.Click += new System.EventHandler(this.Cell1_Click);
			this.Load += new System.EventHandler(this.Page_Load);

		}
		#endregion

		/* Utilities */
		/* --------- */

		private void SwapPlayer( ) {
			currentPlayer = currentPlayer.name.Equals( "x" ) ?
				SymbolTerm.makeSymbol( "o", 0 ) : SymbolTerm.makeSymbol( "x", 0 );
		}

		private string Convert( string s ) {
			return s.Equals( "b" ) ? "  " : s.Equals( "o" ) ? "O" : s.Equals( "x" ) ? "X"
				: "ERROR";
		}
		
		/* Drawing */
		/* ------- */

		private void ResetButtonBackgrounds( ) {
			foreach( Button b in Cells ) 
				b.BackColor = Color.Beige;
		}

		private void DrawWin( ListTerm newBoard ) {
			Term result = newBoard;
			Term elm;
			for (int i = 0; i < 16; i++) {
				elm = ((ListTerm)result).car.dereference();
				if( Convert( elm.ToString() ).Equals( "O" ) ) {
					Cells[ i ].BackColor = Color.Crimson;
					winLock = true;
				}
					
				result = ((ListTerm)result).cdr.dereference();
				if( !( result is ListTerm ) ) 
					break;
			}
		}

		private void DrawBoard( ListTerm newBoard ) {
			Term result = newBoard;
			Term elm;
			for (int i = 0; i < 16; i++) {
				elm = ((ListTerm)result).car.dereference();
				Cells[ i ].Text = Convert( elm.ToString() );
					
				result = ((ListTerm)result).cdr.dereference();
				if( !( result is ListTerm ) )
					break;
			}
		}

		/* Find which cell was clicked */
		/* --------------------------- */

		private void cellClick( object sender, System.EventArgs e ) {
			int cell = -1;
			for( int i = 1; i <= 16; ++i )
				if( Cells[ i - 1 ] == sender )
					cell = i;
			if( cell == -1 )
				throw new Exception( "Internal Error: unexpected cell" );
			if( !winLock )
				HumanMove( cell );
		}

		/* Calls into Prolog */
		/* ----------------- */

		public void ResetBoard( ) {
			ResetButtonBackgrounds( );
			winLock = false;
			currentPlayer = SymbolTerm.makeSymbol( "x", 0 );

			PrologInterface sharp = new PrologInterface( );
			Term a1 = new VariableTerm( );
			Predicate reset = new Blank_1( a1, new ReturnCs( sharp ) );
			sharp.setPredicate( reset );
			sharp.call( );
			
			Term result = a1.dereference();

			if ( !result.isList() || ((ListTerm)result).length() != 16 ){
				Console.WriteLine("Invalid result!");
				return;
			}
			currentBoard = a1.dereference();
			DrawBoard( (ListTerm)( currentBoard ) );
		}

		private void ComputerMove( ) {
			PrologInterface sharp = new PrologInterface( );
			Term a2 = new VariableTerm( );
			Predicate compMove = new Rule_3( currentPlayer, currentBoard,
				a2, new ReturnCs( sharp ) );
			sharp.setPredicate( compMove );
			sharp.call( );
			
			Term result = a2.dereference();
			if ( !result.isList() || ((ListTerm)result).length() != 16 ){
				Console.WriteLine("Invalid result!");
				return;
			}
			currentBoard = a2.dereference();
			DrawBoard( (ListTerm)currentBoard );
			SwapPlayer( );
			CheckForWinningLine( );
		}

		private void CheckForWinningLine( ) {
			PrologInterface sharp = new PrologInterface( );
			Term a2 = new VariableTerm( );
			Predicate win = new WinningLine_2( currentBoard, a2,
				new ReturnCs( sharp ) );
			sharp.setPredicate( win );
			sharp.call( );
			
			Term result = a2.dereference();
			if ( !result.isList() || ((ListTerm)result).length() != 16 ){
				return;
			}
			DrawWin( (ListTerm)result );
		}

		private void HumanMove( int position ) {
			PrologInterface sharp = new PrologInterface( );
			Term a1 = new IntegerTerm( position );
			Term a2 = new VariableTerm( );
			Predicate humanMove = new PlayInGivenPlace_4( currentPlayer, currentBoard,
				a2, a1, new ReturnCs( sharp ) );
			sharp.setPredicate( humanMove );
			sharp.call( );
			
			Term result = a2.dereference();
			if ( !result.isList() || ((ListTerm)result).length() != 16 ){
				Console.WriteLine("Invalid result!");
				return;
			}
			currentBoard = a2.dereference();
			DrawBoard( (ListTerm)currentBoard );
			SwapPlayer( );
			CheckForWinningLine();
		}

		/* Button Clicks */
		/* ------------- */

		private void Cell1_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell2_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell3_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell4_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell5_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell6_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell7_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell8_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell9_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell10_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell11_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell12_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell13_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell14_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell15_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }
		private void Cell16_Click(object sender, System.EventArgs e) { cellClick( sender, e ); }

		private void ResetButton_Click(object sender, System.EventArgs e) { ResetBoard(); }

		private void MoveButton_Click(object sender, System.EventArgs e) {
			if( !winLock )
				ComputerMove( );
		}
	}
}