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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              $gridSize: 40;
$rowSize: 60;
$cellSize: 15px;
$border: 1px solid #EFEFEF;
$background: #CAEBF2;
$alive: #FF3B3F;
$dead: #A9A9A9;
  
* {
  box-sizing: border-box;
}

body {
  background-color: $background;
  width: 100%;
  height: 100%;
  position: relative;
}

#game-container {
  height: auto;
  width: $rowSize * $cellSize + 40px;
  padding: 10px;
  margin: 30px auto;
  background-color: darken($background, 20%);
  border-radius: 4px;
}
#grid {
  width: $rowSize * $cellSize + 2px;
  height: $gridSize * $cellSize + 2px;
  border: $border;
  margin: 15px auto;
  display: block;
  position: relative;
}

.row {
  width: 100%;
  height: $cellSize;
}
.cell {
  width: $cellSize;
  height: $cellSize;
  display: inline-block;
  border: $border;
}
.alive {
  background-color: $alive;
}
.dead {
  background-color: $dead;
}

h1, h4, h5 {
  font-family: 'Helvetica Neue', Arial, sans-serif;
  font-weight: 300;
  text-align: center;
  margin-bottom: 5px;
}

h5 {
  margin-top: 5px;
}

.menu {
  width: 100%;
  margin: 5px auto 0 auto;
  text-align: center;
  font-family: Helvetica Neue;
  font-weight: 300;
  cursor: pointer;
  
  h3 {
    display: inline-block;
    position: relative;
    font-weight: 300;
    padding: 10px;
    margin: 0;
  }
  button {
    display: inline-block;
    position: relative;
    margin: 0 5px;
    padding: 5px 10px;
    background-color: darken($background, 40%);
    border: none;
    border-radius: 4px;
    &:hover {
      background-color: $background;
    }
  }
  .population {
    background-color: lighten($alive, 20%);
  }
  .active {
    background-color: darken($alive, 20%);
    color: #EFEFEF;
  }
}

#debug {
  position: fixed;
  bottom: 5px;
  left: 5px;
  width: 15px;
  height: 15px;
  content: '';
  border: none;
  background-color: darken($background, 10%);
}
            
          
!
            
              // Components
class BaseComponent extends React.Component {
  _bind(...methods) {
    methods.forEach( (method) => this[method] = this[method].bind(this) );
  }
}

class Cell extends BaseComponent {
  constructor(props) {
    super(props);
    this._bind('handleClick');
  }
  handleClick(e) {
    const target = e.target;
    if (target.className === 'cell dead') {
      // target.className = 'cell alive';
      this.props.onChange('add', e.target.id);
    } else {
      // target.className = 'cell dead';
      this.props.onChange('delete', e.target.id);
    }
  }
  render() {
    const status = this.props.value === 1 ? 'cell alive' : 'cell dead';
    const cellId = `${this.props.row}x${this.props.idx}`;
    return (<div className={status} id={cellId} onClick={this.handleClick}></div>)
  }
}

class Row extends BaseComponent {
  constructor(props) {
    super(props);
    this._bind('handleChange');
  }
  handleChange(type, cell) {
    this.props.onChange(type, cell);
  }
  render() {
    const cells = this.props.cells.map((cell, idx) => <Cell row={this.props.row} value={cell[0]} sum={cell[1]} idx={idx} onChange={this.handleChange} />);
    return (<div className="row">
      {cells}
    </div>);
  }
}
                                     
class Grid extends BaseComponent {
  constructor(props) {
    super(props);
    this._bind('handleChange');
  } 
  handleChange(type, cell) {
    this.props.onChange(type, cell);
  }
  render() {
    const rows = this.props.grid.map((row, idx) => <Row cells={row} row={idx} onChange={this.handleChange}/>);            
    return (<div id="grid">
      {rows}
    </div>)
  }
}

class App extends BaseComponent {
  constructor() {
    super();
    this.state = { 
      grid: [], 
      counter: 0, 
      paused: false, 
      gridSize: 40, 
      rowSize: 60, 
      ratio: 0.7 };
    this._bind(
      'updateState', 
      'buildGrid', 
      'findSums', 
      'applyRules', 
      'start', 
      'stop', 
      'clear', 
      'handleChange', 
      'more', 
      'fewer', 
      'normal', 
      'printout',
    );
  }
  componentWillMount() {
    this.updateState();
  }
  componentDidMount() {
    this.setState({update: false});
  }
  shouldComponentUpdate(nextProps, nextState) {
    if (this.state.update === true) {
      return true;
    }
  }
  updateState() {
    let oldGrid = this.state.grid;
    let newGrid = [];
    let counter = this.state.counter;
    let rows = this.state.gridSize;
    let cells = this.state.rowSize;
    if (counter === 0 && oldGrid.length === 0) {
      newGrid = this.buildGrid(oldGrid, rows, cells);
    } else {
      newGrid = this.applyRules(oldGrid);
    }
    newGrid = this.findSums(newGrid);
    counter++;
    this.setState({ grid: newGrid, counter: counter, update: true});
    this.intervalID = requestAnimationFrame(this.updateState);
  }
  buildGrid(grid, rows, cells) {
    for (let  row = 0; row < rows; row++) {
      grid.push([]);
      for (let cell = 0; cell < cells; cell++) {
        const r = Math.random();
        if(r > this.state.ratio) {
          grid[row].push([1]);
        } else {
          grid[row].push([0]);
        }
      }
    }
    return grid;
  }
  findSums(grid) {
    let newGrid = [];
    grid.forEach((row, rIdx) => {
      let newRow = [];
      row.forEach((cell, cIdx) => {
         let newArr = [];
         newArr.push(cell[0]);
         const neighbourhood = [
          [(rIdx - 1),(cIdx - 1)],
          [(rIdx - 1),(cIdx)],
          [(rIdx - 1),(cIdx + 1)],
          [(rIdx),(cIdx-1)],
          [(rIdx),(cIdx)],
          [(rIdx),(cIdx + 1)],
          [(rIdx + 1),(cIdx - 1)],
          [(rIdx + 1),(cIdx)],
          [(rIdx + 1),(cIdx + 1)]
        ];
        let nValues = neighbourhood.map(arr => {
          let x = arr[0]
          let y = arr[1]
          if (x < 0) {
            x = x + this.state.gridSize;
          } else if (x >= this.state.gridSize) {
            x = x - this.state.gridSize;
          }
          if (arr[0] < 0) {
            
          }
          if (arr[0] < 0 || arr[1] < 0 || arr[0] >= this.state.gridSize || arr[1] >= this.state.rowSize) {
            return 0;
          } else {
            return grid[arr[0]][arr[1]][0];
          }
        });
        let sum = nValues.reduce((sumValues ,n) => sumValues + n);
        newArr.push(sum);
        newRow.push(newArr);
      });
      newGrid.push(newRow);
    });
    return newGrid;
  }
  applyRules(grid) {
    let newGrid = []
    grid.map(row => {
      let newRow = [];
      row.map(cell => {
        const value = cell[0];
        const sum = cell[1];
        if (sum === 3) {
          newRow.push([1]);
        } else if (sum === 4) {
          newRow.push([value]);
        } else {
          newRow.push([0]);
        }
      });
      newGrid.push(newRow);
    });
    return newGrid;
  }
  start() {
    this.setState({ paused: false });
    this.intervalID = requestAnimationFrame(this.updateState);
  }
  stop() {
    cancelAnimationFrame(this.intervalID);
    this.setState({paused: true});
  }
  clear() {
    const grid = this.state.grid;
    if (this.state.paused !== false) {
      cancelAnimationFrame(this.intervalID);
      this.setState({ paused: true });
    }
    let newGrid = [];
    grid.map(row => {
      let newRow = [];
      row.map(cell => newRow.push([0]));
      newGrid.push(newRow);
    });
    this._tempGrid = newGrid;
    this.setState({paused: true, counter: 0, grid: newGrid, update: true});
  }
  handleChange(type, cell) {
    let grid = this.state.grid;
    let arr = cell.split('x');
    if (this.state.paused === true && this.state.counter === 0 && this.state.timer === null) {
      if (type === 'add') {
        grid[arr[0]][arr[1]][0] = 1;
      } else if (type === 'delete') {
        grid[arr[0]][arr[1]][0] = 0;
      }
      let newGrid = this.findSums(grid);
      this.setState({grid: newGrid, update: true});
    } else if (this.state.paused === false) {
      alert('You must pause the simulation and clear the board before you can set up your own.');
    } else if (this.state.counter > 0) {
      alert('You must reset the simulation by pressing "Clear" before you can customize the board.');
    }
  }
  more() {
    cancelAnimationFrame(this.intervalID);
    this.clear();
    this.setState({ ratio: 0.5, grid: [], counter: 0, update: true});
    this.start();
  }
  fewer() {
    cancelAnimationFrame(this.intervalID);
    this.clear();
    this.setState({ ratio: 0.9, grid: [], counter: 0, update: true});
    this.start();
  }
  normal() {
    cancelAnimationFrame(this.intervalID);
    this.clear();
    this.setState({ ratio: 0.7, grid: [], counter: 0, update: true});
    this.start();
  }
  printout() {
    console.log(JSON.stringify(this.state));
  }
  render() { 
    const playPause = this.state.paused === true ? <button id="start" onClick={this.start}><i className="fa fa-play"></i></button> :
      <button id="stop" onClick={this.stop}><i className="fa fa-pause"></i></button>;
    return (<div class="container">
      <h1>Conway's Game of Life</h1>
      <h5><a href="https://en.wikipedia.org/wiki/Conway%27s_Game_of_Life">Click here for an explanation</a></h5>
      <h5>To make your own custom starting state, press clear, click on some squares, and then press Play.</h5>
      <div id="game-container">
        <div className="menu">
          <h3>Generation: {this.state.counter}</h3>
          {playPause}
          <button id="clear" onClick={this.clear}>Clear</button>
        </div><div className="menu">
          <h3 id="restart">Restart with:</h3>
            <button value="0.9" name="population" id="fewer" onClick={this.fewer}>Fewer</button>
          <button value="0.9" name="population" id="fewer" onClick={this.normal}>Normal Amount</button>
          <button value="0.9" name="population" id="fewer" onClick={this.more}>More</button>
        </div>  
        <Grid grid={this.state.grid} onChange={this.handleChange} />
      </div>
        <h4>Coded by <a href="http://lukewalker.org" target="_blank">Luke Walker</a>, to complete <a href="https://www.freecodecamp.com/challenges/build-the-game-of-life" target="_blank">this Free Code Camp project</a>.</h4>
        <button id="debug" onClick={this.printout}></button>
    </div>)
  }
}

ReactDOM.render(<App />, document.querySelector('#app'));


            
          
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