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<h2>Minesweeper React</h2>
<h5>Based on the classic game, <a target="_new" href="http://en.wikipedia.org/wiki/Minesweeper_(video_game)">Minesweeper</a></h5>
<main id="app"></main>
body, html
{
padding: 1rem;
}
#game-container {
float: left;
border: 1px solid #CCC;
margin-bottom: 10px;
padding: 15px;
}
.row
{
display: flex;
}
.cell {
width: 35px;
height: 25px;
border: 1px solid #CCC;
padding: 10px 5px 5px 5px;
background-color: #EEE;
font-size: 16px;
text-align: center;
box-shadow: inset 5px 5px 10px #FFF, inset -3px -3px 5px #777;
cursor: pointer;
transition-property: background-color, box-shadow;
transition-duration: 1s;
transition-timing-function: ease-out;
}
.cell::selection {
background: transparent;
}
.cell.revealed, .cell.flagged {
cursor: default;
}
.cell.revealed {
background-color: #DDD;
-webkit-box-shadow: none;
-moz-box-shadow: none;
box-shadow: none;
}
$cellColors: (
1: 'blue',
2: 'green',
3: 'red',
4: 'purple',
5: 'maroon',
6: 'turquoise',
7: 'black',
8: 'white'
);
@each $name, $value in $cellColors {
.cell.revealed.adj-#{$name} {
color: #{$value};
}
}
.cell.revealed.adj-M {
font-family: "FontAwesome";
background-color: #FFCCCC;
&:after
{
content: '\f1e2';
}
}
.cell.flagged {
font-family: "FontAwesome";
&:after
{
content: '\f024';
}
}
.clearfix:after {
visibility: hidden;
display: block;
content: "";
clear: both;
height: 0;
}
.status-msg {
margin-bottom: 10px;
}
label {
margin-right: 10px;
}
input[type="number"] {
width: 70px;
margin-right: 10px;
}
.m10 {
margin: 10px 0;
}
.small-font
{
font-size: .85rem;
}
/*
Minesweeper.js
Author: Brian Glaz
Desccription:
React implementation of the classc game, Minesweeper
*/
class GameContainer extends React.Component {
constructor() {
super();
this.state = {
grid: [], //will hold an array or cells
minesFound: 0, //number of mines correctly flagged by user
falseMines: 0, //number of mines incorrectly flagged
minesRemaining: 10, //total number of mines - mines flagged
statusMsg: "Playing...", //game status msg, 'Won','Lost', or 'Playing'
statusMsgColor: "#000000", //status message font color
playing: true,
movesMade: 0, //keep track of the number of moves
options: {
rows: 8, //number of rows in the grid
cols: 8, //number of columns in the grid
mines: 10 //number of mines in the grid
},
userOptions: {
rows: 8,
cols: 8,
mines: 10
}
};
const methodsToBind = [
"flagCell",
"revealCell",
"newGame",
"validate",
"handleMinMaxInputBlur",
"gridToConsole"
];
methodsToBind.forEach(
methodName => (this[methodName] = this[methodName].bind(this))
);
//save initial state
this.initialState = { ...this.state };
if (!!localStorage["minesweeper-react"]) {
this.loadFromLocal();
} else {
this.init(true);
}
}
init(constructing = false) {
const state = this.state,
grid = Array.from(state.grid);
//populate the grid with cells
for (let r = 0; r < state.options["rows"]; r++) {
grid.push([]);
for (let c = 0; c < state.options["cols"]; c++) {
grid[r].push({
xpos: c,
ypos: r,
isMine: false,
isRevealed: false,
isFlagged: false,
value: 0
});
}
}
//randomly assign mines
if (state.options.mines > state.options.rows * state.options.cols) {
state.options.mines = state.options.rows * state.options.cols;
}
let assignedMines = 0;
while (assignedMines < state.options.mines) {
let ypos = Math.floor(Math.random() * state.options.rows),
xpos = Math.floor(Math.random() * state.options.cols),
cell = grid[ypos][xpos];
//assign and increment if cell is not already a mine
if (!cell.isMine) {
cell.isMine = true;
cell.value = "M";
assignedMines++;
}
}
//update cell values, check for adjacent mines
for (let ypos = 0; ypos < state.options["rows"]; ypos++) {
for (let xpos = 0; xpos < state.options["cols"]; xpos++) {
//no need to update mines
if (!grid[ypos][xpos].isMine) {
let mineCount = 0,
adjCells = this.getAdjacentCells(xpos, ypos, grid);
for (let i = adjCells.length; i--; ) {
if (adjCells[i].isMine) {
mineCount++;
}
}
grid[ypos][xpos].value = mineCount;
}
}
}
if (constructing) {
state.grid = grid;
} else {
this.setState({ grid });
}
}
newGame() {
const state = this.state,
userOptions = state.userOptions, //grab a copy of user options from inputs
newState = { ...this.initialState, userOptions, options: userOptions }; //apply user options on top of default options
newState.minesRemaining = newState.options.mines;
this.setState(newState, this.init);
}
getAdjacentCells(xpos, ypos, grid = []) {
const state = this.state;
let results = [];
for (
let rowPos = ypos > 0 ? -1 : 0;
rowPos <= (ypos < state.options.rows - 1 ? 1 : 0);
rowPos++
) {
for (
let colPos = xpos > 0 ? -1 : 0;
colPos <= (xpos < state.options.cols - 1 ? 1 : 0);
colPos++
) {
results.push(Object.assign({}, grid[ypos + rowPos][xpos + colPos]));
}
}
return results;
}
revealCell(xpos, ypos, moveCount = false) {
const state = this.state,
grid = Array.from(state.grid);
let cell = grid[ypos][xpos];
if (!cell.isRevealed && !cell.isFlagged && state.playing) {
cell.isRevealed = true;
//end the game if user clicked a mine
if (cell.isMine) {
this.setState({
statusMsg: "Sorry, you lost!",
playing: false,
statusMsgColor: "#EE0000"
});
} else if (!cell.isFlagged && cell.value == 0) {
//if the clicked cell has 0 adjacent mines, we need to recurse to reveal out all adjacent 0 cells
const adjCells = this.getAdjacentCells(cell.xpos, cell.ypos, grid);
for (let i = 0, len = adjCells.length; i < len; i++) {
this.revealCell(adjCells[i].xpos, adjCells[i].ypos, grid);
}
}
if (moveCount) {
this.setState({ movesMade: state.movesMade + 1 });
}
this.setState({ grid });
}
}
flagCell(xpos, ypos, e) {
e.preventDefault();
const state = this.state,
grid = Array.from(state.grid);
let cell = grid[ypos][xpos];
if (!cell.isRevealed && state.playing) {
if (!cell.isFlagged) {
cell.isFlagged = true;
this.setState({ minesRemaining: state.minesRemaining - 1 });
if (cell.isMine) {
this.setState({ minesFound: state.minesFound + 1 });
} else {
this.setState({ falseMines: state.falseMines + 1 });
}
} else {
cell.isFlagged = false;
this.setState({ minesRemaining: state.minesRemaining + 1 });
if (cell.isMine) {
this.setState({ minesFound: state.minesFound - 1 });
} else {
this.setState({ falseMines: state.falseMines + 1 });
}
}
this.setState({ grid, movesMade: state.movesMade + 1 });
}
}
validate() {
const state = this.state;
if (state.minesFound == state.options.mines && state.falseMines == 0) {
this.setState({
statusMsg: "You won!!",
playing: false,
statusMsgColor: "#00CC00"
});
} else {
this.setState({
statusMsg: "Sorry, you lost!",
playing: false,
statusMsgColor: "#EE0000"
});
}
}
handleMinMaxInputBlur(newStateObj = {}) {
let newState = Object.assign({ ...this.state.userOptions }, newStateObj);
this.setState({ userOptions: newState });
}
gridToConsole() {
const state = this.state;
let result = "";
for (let r = 0, r_len = state.grid.length; r < r_len; r++) {
for (let c = 0, c_len = state.grid[r].length; c < c_len; c++) {
result += state.grid[r][c].value + " ";
}
result += "\n";
}
console.log(result);
}
saveToLocal(nextState) {
const jsonData = JSON.stringify(nextState);
localStorage["minesweeper-react"] = jsonData;
}
loadFromLocal() {
this.state = JSON.parse(localStorage["minesweeper-react"]);
}
componentWillUpdate(nextProps, nextState) {
this.saveToLocal(nextState);
}
render() {
const state = this.state;
return (
<div>
<section id="game-cotainer" className="clearfix">
{state.grid.map((row, ypos) => {
return (
<div className="row" key={`row-${ypos}`}>
{row.map((col, xpos) => {
const cell = state.grid[ypos][xpos];
return (
<Cell
key={`cell-${xpos}-${ypos}`}
value={cell.value}
isRevealed={cell.isRevealed}
isFlagged={cell.isFlagged}
isMine={cell.isMine}
xpos={cell.xpos}
ypos={cell.ypos}
onLeftClick={this.revealCell}
onRightClick={this.flagCell}
/>
);
})}
</div>
);
})}
</section>
<div>
<div className="m10">
F = Flagged, M = Mine, Left Click to reveal a cell, Right Click to
flag a cell
</div>
<div className="status-msg">
<strong>Mines Remaining:</strong> {state.minesRemaining}
</div>
<div className="status-msg">
<strong>Moves Made:</strong> {state.movesMade}
</div>
<div className="status-msg">
<strong>Game Status:</strong>{" "}
<span style={{ color: state.statusMsgColor }}>
{state.statusMsg}
</span>
</div>
<div className="m10">
<input type="button" value="Did I win?" onClick={this.validate} />
</div>
<div className="m10">
<label for="new_rows">Rows:</label>
<MinMaxInput
stateVal="rows"
placeholder="rows"
min="3"
max="19"
value={state.userOptions.rows}
onBlur={this.handleMinMaxInputBlur}
/>
<label for="new_cols">Cols:</label>
<MinMaxInput
stateVal="cols"
placeholder="cols"
min="3"
max="19"
value={state.userOptions.cols}
onBlur={this.handleMinMaxInputBlur}
/>
<label for="new_mines">Mines:</label>
<MinMaxInput
stateVal="mines"
placeholder="mines"
min="1"
max={state.userOptions.cols * state.userOptions.rows}
value={state.userOptions.mines}
onBlur={this.handleMinMaxInputBlur}
/>
<div className="small-font">*max size: 19 x 19</div>
<input
type="button"
className="m10"
value="Create new game!"
onClick={this.newGame}
/>
</div>
<div>
<input type="button" value="Cheat!" onClick={this.gridToConsole} />
<div className="small-font">*grid layout printed to JS console</div>
</div>
</div>
</div>
);
}
}
//Cell component representing individual cells on the game board
const Cell = props => {
const {
value,
isRevealed,
isFlagged,
isMine,
xpos,
ypos,
onLeftClick,
onRightClick
} = props;
const getCssClasses = () => {
return classNames("cell", `adj-${value}`, {
revealed: isRevealed,
flagged: isFlagged
});
};
const handleClick = e => {
onLeftClick(xpos, ypos, true);
};
const handleRightClick = e => {
onRightClick(xpos, ypos, e);
};
return (
<div
className={getCssClasses()}
onClick={handleClick}
onContextMenu={handleRightClick}
>
{isRevealed && !isMine && value !== 0 ? value : ""}
</div>
);
};
//Helper input component to validate user inputted options
const MinMaxInput = props => {
const { min, max, placeholder, stateVal, value, onBlur } = props;
const handleBlur = e => {
let val = parseInt(e.target.value);
if (val < min) {
val = min;
} else if (val > max) {
val = max;
}
e.target.value = val;
let returnObj = {};
returnObj[stateVal] = val;
onBlur(returnObj);
};
return (
<input
type="number"
placeholder={placeholder}
defaultValue={value}
min={min}
max={max}
onBlur={handleBlur}
/>
);
};
ReactDOM.render(<GameContainer />, document.getElementById("app"));
Also see: Tab Triggers