var width = 450;
var height = 450;
var me = true;
var over = false;

var wins = []; //算法  三维数组 记录所有的赢法组合
for(var i = 0; i < 15; i++) {
	wins[i] = [];
	for(var j = 0; j < 15; j++) {
		wins[i][j] = [];
	}
}

var count = 0;
for(var i = 0; i < 15; i++) { //所有横向的赢法
	for(var j = 0; j < 11; j++) {

		// wins[0][0][0] = true
		// wins[0][1][0] = true
		// wins[0][2][0] = true
		// wins[0][3][0] = true
		// wins[0][4][0] = true

		// wins[0][1][1] = true
		// wins[0][2][1] = true
		// wins[0][3][1] = true
		// wins[0][4][1] = true
		// wins[0][5][1] = true

		for(var k = 0; k < 5; k++) {
			wins[i][j + k][count] = true;
		}
		count++;
	}
}

for(var i = 0; i < 15; i++) { //所有竖向的赢法
	for(var j = 0; j < 11; j++) {
		for(var k = 0; k < 5; k++) {
			wins[j + k][i][count] = true;
		}
		count++;
	}
}

for(var i = 0; i < 11; i++) { //所有斜线的赢法
	for(var j = 0; j < 11; j++) {
		for(var k = 0; k < 5; k++) {
			wins[i + k][j + k][count] = true;
		}
		count++;
	}
}
for(var i = 0; i < 11; i++) { //所有反斜线的赢法
	for(var j = 14; j > 3; j--) {
		for(var k = 0; k < 5; k++) {
			wins[i + k][j - k][count] = true;
		}
		count++;
	}
}

console.log("共有" + count + "种赢法"); //572种赢法

/**
 * 赢法统计数组
 */
var myWin = [];
var computerWin = [];

for(var i = 0; i < count; i++) { //所有反斜线的赢法
	myWin[i] = 0;
	computerWin[i] = 0;
}

var chessBoard = []; //记录已经下过的棋子
for(var i = 0; i < 15; i++) {
	chessBoard[i] = [];
	for(var j = 0; j < 15; j++) {
		chessBoard[i][j] = 0;
	}
}

var chess = document.getElementById('chess');
var context = chess.getContext('2d');

context.strokeStyle = "#BFBFBF";

var logo = new Image();
logo.src = 'favicon.ico';
logo.onload = function() {
	//context.drawImage(logo, 15 + 5 * 30, 15 + 5 * 30, 120, 120);
	drawChessBoard();
	if(!localStorage.getItem("hasTip")) {
		showAlert("你为黑子，计算机为白子", 50);
		localStorage.setItem("hasTip", true);
	}
}

function drawChessBoard() {
	for(var i = 0; i < 15; i++) {
		context.moveTo(15 + i * 30, 15); //画竖线
		context.lineTo(15 + i * 30, 435); //画竖线
		context.stroke(); //描边

		context.moveTo(15, 15 + i * 30); //画横线
		context.lineTo(435, 15 + i * 30); //画横线
		context.stroke();
	}
}

function oneStep(i, j, me) {

	context.beginPath();
	context.arc(15 + i * 30, 15 + j * 30, 13, 0, 2 * Math.PI);
	context.closePath();
	var gradient = context.createRadialGradient(15 + i * 30 + 2, 15 + j * 30 - 2, 13, 15 + i * 30 + 2, 15 + j * 30 - 2, 0);
	if(me) {
		gradient.addColorStop(0, "#0A0A0A");
		gradient.addColorStop(1, "#636766");
	} else {
		gradient.addColorStop(0, "#D1D1D1");
		gradient.addColorStop(1, "#F9F9F9");
	}
	context.fillStyle = gradient;
	context.fill(); //填充
}

chess.onclick = function(e) {
	if(over) {
		return;
	}
	if(!me) {
		return;
	}

	var x = e.offsetX;
	var y = e.offsetY;
	var i = Math.floor(x / 30);
	var j = Math.floor(y / 30);

	if(chessBoard[i][j] == 0) {
		oneStep(i, j, me);
		chessBoard[i][j] = 1;
		for(var k = 0; k < count; k++) {
			if(wins[i][j][k]) {
				myWin[k]++;
				computerWin[k] = 6;
				if(myWin[k] == 5) {
					console.log("you win");
					//window.alert("you win"); //会有阻塞
					showAlert("you win", 50);
					over = true;
				}
			}
		}
		if(!over) {
			me = !me;
			computerAI();
		}
	}
	//console.log(JSON.stringify(chessBoard));
}

function computerAI() {
	var myScore = [];
	var computerScore = [];
	var max = 0; //最高分
	var u = 0,
		v = 0; //坐标

	for(var i = 0; i < 15; i++) {
		myScore[i] = [];
		computerScore[i] = [];
		for(var j = 0; j < 15; j++) {
			myScore[i][j] = 0;
			computerScore[i][j] = 0;
		}
	}
	for(var i = 0; i < 15; i++) {
		for(var j = 0; j < 15; j++) {
			if(chessBoard[i][j] == 0) { //空闲的点
				for(var k = 0; k < count; k++) {
					if(wins[i][j][k]) {
						if(myWin[k] == 1) {
							myScore[i][j] += 200;
						} else if(myWin[k] == 2) {
							myScore[i][j] += 400;
						} else if(myWin[k] == 3) {
							myScore[i][j] += 2000;
						} else if(myWin[k] == 4) {
							myScore[i][j] += 10000
						}
						if(computerWin[k] == 1) {
							computerScore[i][j] += 220;
						} else if(computerWin[k] == 2) {
							computerScore[i][j] += 420;
						} else if(computerWin[k] == 3) {
							computerScore[i][j] += 2100;
						} else if(computerWin[k] == 4) {
							computerScore[i][j] += 20000
						}
					}
				}

				if(myScore[i][j] > max) {
					max = myScore[i][j];
					u = i;
					v = j;
				} else if(myScore[i][j] == max) {
					if(computerScore[i][j] > computerScore[u][v]) {
						u = i;
						v = j;
					}
				}
				if(computerScore[i][j] > max) {
					max = computerScore[i][j];
					u = i;
					v = j;
				} else if(computerScore[i][j] == max) {
					if(computerScore[i][j] > computerScore[u][v]) {
						u = i;
						v = j;
					}
				}
			}
		}
	}
	oneStep(u, v, false);
	chessBoard[u][v] = 2;
	for(var k = 0; k < count; k++) {
		if(wins[u][v][k]) {
			computerWin[k]++;
			myWin[k] = 6;
			if(computerWin[k] == 5) {
				console.log("computer win");
				showAlert("computer win", 50);
				//window.alert("computer win"); //会有阻塞
				over = true;
			}
		}
	}
	if(!over) {
		me = !me;
	}
}

function showAlert(content, delay) { //避免alert阻塞线程
	setTimeout(function() {
		alert(content);
	}, (delay && delay > -1) ? delay : 300);
}