commit b2ba582cecac45cbea3af998ace0d6b4b958ced1
Author: hkri <hkri@protonmail.com>
Date:   Sun Jul 25 22:26:58 2021 +0800

    Add initial codes.

diff --git a/README.md b/README.md
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+# Number Slide
+
+Simple number slide game using HTML and vanila JavaScript.
+
+<div align="center">
+  <img src="screenshot.png"/>
+</div>
+
+## Development
+
+- Open `index.html` on a modern browser.
+- Edit the files on your favorite text editor.
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diff --git a/dist/app.css b/dist/app.css
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+body {
+  padding: 0;
+  margin: 0;
+  background-color: rgb(240, 240, 244);
+  font-family: sans-serif;
+}
+
+main {
+  background-color: rgb(230, 230, 234);
+  border-radius: 8px;
+}
+
+h1 {
+  font-size: 2.5em;
+  color: rgb(57, 57, 61);
+  margin: 0;
+  width: 100%;
+}
+
+footer {
+  text-align: center;
+  font-size: 12px;
+  color: rgb(110, 110, 114);
+  text-transform: uppercase;
+}
+
+footer a {
+  color: rgb(110, 110, 114);
+  text-decoration: none;
+}
+
+footer a:hover {
+  text-decoration: underline;
+}
+
+#wrapper {
+  margin: 0 auto;
+  max-width: 500px;
+  width: 100%;
+  margin: 0 auto;
+  padding: 0 2em;
+  box-sizing: border-box;
+}
+
+#controls {
+  display: flex;
+  margin: 2em 0 1em 0;
+  justify-content: center;
+  align-items: center;
+}
+
+#controls button {
+  background-color: rgb(220, 220, 224);
+  border: 0;
+  border-radius: 6px;
+  padding: 0.7em 1.5em;
+  transition: all 0.12s ease-out;
+}
+
+#controls button:not([disabled]):hover {
+  cursor: pointer;
+  background-color: #04bbd9;
+  color: white;
+}
+
+#stage {
+  margin: 4em auto 6em auto;
+}
+
+#stage section {
+  width: 100%;
+  min-height: 130px;
+  border-radius: 8px;
+  position: relative;
+  display: grid;
+  grid-template-columns: [c1] 33.33% [c2] 33.33% [c3] 33.33% [c-end];
+  grid-template-rows: [r1] 33.33% [r2] 33.33% [r3] 33.33% [r-end];
+  filter: drop-shadow(0 0 8px rgba(0, 0, 0, 0.15));
+}
+
+#stage button {
+  margin: 0;
+  padding: 0;
+  font-size: 3em;
+  background: rgb(250, 250, 252);
+  color: rgb(50, 50, 55);
+  overflow: hidden;
+  transition: transform 0.12s ease-out, background-color 0.12s ease-out;
+  border-radius: 8px;
+  border: 1px solid rgb(198, 198, 201);
+  grid-column-start: c1;
+  grid-row-start: r1;
+  z-index: 1;
+}
+
+#stage button.fast {
+  transition: transform 0.08s ease-out;
+}
+
+#stage.done button[disabled] {
+  background-color: #20a076;
+  color: white;
+}
+
+.c1.r1 { transform: translate(0, 0); }
+.c1.r2 { transform: translate(0, 100%); }
+.c1.r3 { transform: translate(0, 200%); }
+
+.c2.r1 { transform: translate(100%, 0); }
+.c2.r2 { transform: translate(100%, 100%); }
+.c2.r3 { transform: translate(100%, 200%); }
+
+.c3.r1 { transform: translate(200%, 0); }
+.c3.r2 { transform: translate(200%, 100%); }
+.c3.r3 { transform: translate(200%, 200%); }
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diff --git a/dist/app.js b/dist/app.js
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+var grid = [1, 2, 3, 4, 5, 6, 7, 8, 0 ];
+var COLS = 3;
+var ROWS = grid.length / COLS;
+var SHUFFLES = 35;
+
+var MOV_LEFT = 0;
+var MOV_RIGHT = 1;
+var MOV_UP = 2;
+var MOV_DOWN = 3;
+
+var tiles = document.querySelectorAll('#stage button');
+var textTime = document.getElementById('time');
+var buttonShuffle = document.getElementById('shuffle');
+var stage = document.getElementById('stage');
+var stageSection = document.querySelector('#stage section');
+var wrapper = document.getElementById('wrapper');
+
+var timer = null;
+var startTime = 0;
+
+function getRow(index) {
+  return Math.floor(index / COLS);
+}
+
+function getCol(index) {
+  return (index % COLS);
+}
+
+function render() {
+  grid.forEach(function (value, index) {
+    var col = getCol(index) + 1;
+    var row = getRow(index) + 1;
+    var element = document.getElementById(value);
+    if (element === null) {
+      return;
+    }
+    element.classList.remove('c1', 'c2', 'c3', 'r1', 'r2', 'r3');
+    element.classList.add('c' + col, 'r' + row);
+  });
+}
+
+function swap(a, b) {
+  var tmp = grid[a];
+  grid[a] = grid[b];
+  grid[b] = tmp;
+}
+
+function getSpacePossibleMoves(reverseDir) {
+  var index = grid.indexOf(0);
+  var possibleMoves = new Set([MOV_LEFT, MOV_RIGHT, MOV_UP, MOV_DOWN]);
+  if (index % COLS == COLS - 1)
+    possibleMoves.delete(MOV_RIGHT);
+  if (index % COLS == 0)
+    possibleMoves.delete(MOV_LEFT);
+  if (Math.floor(index / ROWS) == 0)
+    possibleMoves.delete(MOV_UP);
+  if (Math.floor(index / ROWS) == ROWS - 1)
+    possibleMoves.delete(MOV_DOWN);
+  possibleMoves.delete(reverseDir);
+  return Array.from(possibleMoves);
+}
+
+function moveSpace(direction) {
+  var index = grid.indexOf(0);
+  var step = 0;
+  switch (direction) {
+    case MOV_LEFT: case MOV_UP:
+      step = -1;
+      break;
+    case MOV_RIGHT: case MOV_DOWN:
+      step = 1;
+      break;
+    default:
+      step = 0;
+  }
+  if ([MOV_LEFT, MOV_RIGHT].indexOf(direction) > -1) {
+    // horizontal
+    var inc = index + step;
+    if (inc < 2 || inc >= 0) {
+      swap(index, inc);
+    }
+  } else {
+    // vertical
+    var inc = index + (ROWS * step);
+    if (inc < grid.length || inc >= 0) {
+      swap(index, inc);
+    }
+  }
+  render();
+}
+
+function moveHorizontal(index) {
+  var col = getCol(index);
+  if (col == 0) {
+    if (grid[index + 1] == 0)
+      swap(index, index + 1);
+  } else if (col == COLS - 1) {
+    if (grid[index - 1] == 0)
+      swap(index, index - 1);
+  } else {
+    if (grid[index + 1] == 0)
+      swap(index, index + 1);
+    else if (grid[index - 1] == 0)
+      swap(index, index - 1);
+  }
+}
+
+function moveVertical(index) {
+  var row = getRow(index);
+  if (row == 0) {
+    if (grid[index + ROWS] == 0)
+      swap(index, index + ROWS);
+  } else if (row == ROWS - 1) {
+    if (grid[index - ROWS] == 0)
+      swap(index, index - ROWS);
+  } else {
+    if (grid[index + ROWS] == 0)
+      swap(index, index + ROWS);
+    else if (grid[index - ROWS] == 0)
+      swap(index, index - ROWS);
+  }
+}
+
+function shuffle(steps) {
+  var i = 0;
+  var prevDir = -1;
+  tiles.forEach(function (tile) {
+    tile.classList.add('fast');
+  });
+  var loop = setInterval(function () {
+    var reverseDir = -1;
+    if (prevDir == MOV_DOWN)
+      reverseDir = MOV_UP;
+    if (prevDir == MOV_UP)
+      reverseDir = MOV_DOWN;
+    if (prevDir == MOV_LEFT)
+      reverseDir = MOV_RIGHT;
+    if (prevDir == MOV_RIGHT)
+      reverseDir = MOV_LEFT;
+    var possibleMoves = getSpacePossibleMoves(reverseDir);
+    var dir = possibleMoves[Math.floor(Math.random() * possibleMoves.length)];
+    moveSpace(dir);
+    prevDir = dir;
+    i++;
+    if (i >= steps) {
+      clearInterval(loop);
+      enableTiles();
+      document.getElementById('stage').classList.remove('done');
+      buttonShuffle.disabled = false;
+      tiles.forEach(function (tile) {
+        tile.classList.remove('fast');
+      });
+      return;
+    }
+  }, 90);
+  disableTiles();
+  buttonShuffle.disabled = true;
+}
+
+function formatTime(time) {
+  var minutes = Math.floor(time / 60).toString().padStart(2, '0');
+  var seconds = Math.floor(time % 60).toString().padStart(2, '0');
+  var millis = Math.floor((time % 1) * 100).toString().padStart(2, '0');
+  return minutes + ':' + seconds + '.<small>' + millis + '</small>';
+}
+
+function startTimer() {
+  if (timer !== null) {
+    return;
+  }
+  startTime = (new Date()).getTime();
+  timer = setInterval(function () {
+    var diff = ((new Date()).getTime() - startTime) / 1000;
+    textTime.innerHTML = formatTime(diff);
+  }, 16);
+}
+
+function stopTimer() {
+  clearInterval(timer);
+  timer = null;
+}
+
+function resetTimer() {
+  stopTimer();
+  startTime = 0;
+  textTime.innerHTML = formatTime(0);
+}
+
+function checkCompleted() {
+  for (var i = 0; i < grid.length - 2; ++i) {
+    if (grid[i + 1] < grid[i]) {
+      return;
+    }
+  }
+  document.getElementById('stage').classList.add('done');
+  disableTiles();
+  stopTimer();
+}
+
+function disableTiles() {
+  tiles.forEach(function (button) {
+    button.disabled = true;
+  });
+}
+
+function enableTiles() {
+  tiles.forEach(function (button) {
+    button.disabled = false;
+  });
+}
+
+function resizeStage() {
+  var wrapperStyle = getComputedStyle(wrapper);
+  var paddingLeft = parseInt(wrapperStyle.getPropertyValue('padding-left'));
+  var paddingRight = parseInt(wrapperStyle.getPropertyValue('padding-right'));
+  var width = parseInt(wrapperStyle.getPropertyValue('width'));
+  var adjustedWidth = width - paddingLeft - paddingRight;
+  while (adjustedWidth % 3 != 0) {
+    adjustedWidth--;
+  }
+  stage.style.fontSize = (adjustedWidth / 24) + 'px';
+  stage.style.width = adjustedWidth + 'px';
+  stageSection.style.height = adjustedWidth + 'px';
+}
+
+tiles.forEach(function (button) {
+  button.onclick = function (e) {
+    var tileId = e.target.id;
+    var index = grid.indexOf(parseInt(tileId));
+    moveHorizontal(index);
+    moveVertical(index);
+    render();
+    startTimer();
+    checkCompleted();
+  }
+});
+
+buttonShuffle.onclick = function () {
+  resetTimer();
+  shuffle(SHUFFLES);
+}
+
+window.onload = function () {
+  resizeStage();
+  render();
+  shuffle(SHUFFLES);
+};
+
+window.onresize = resizeStage;
diff --git a/dist/index.html b/dist/index.html
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+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <meta http-equiv="X-UA-Compatible" content="IE=edge">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <link rel="stylesheet" href="app.css"/>
+  <title>Number Slide</title>
+</head>
+<body>
+  <div id="wrapper">
+    <div id="controls">
+      <h1 id="time">00:00.<small>00</small></h1>
+      <button id="shuffle" disabled>Shuffle</button>
+    </div>
+    <main id="stage">
+      <section>
+        <button id="1" class="c1 r1">1</button>
+        <button id="2" class="c2 r1">2</button>
+        <button id="3" class="c3 r1">3</button>
+        <button id="4" class="c1 r2">4</button>
+        <button id="5" class="c2 r2">5</button>
+        <button id="6" class="c3 r2">6</button>
+        <button id="7" class="c1 r3">7</button>
+        <button id="8" class="c2 r3">8</button>
+      </section>
+    </main>
+    <footer>
+      2021 &copy; <a href="https://johnespiritu.dev">John Espiritu</a>
+    </footer>
+  </div>
+  <script src="app.js"></script>
+</body>
+</html>
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diff --git a/screenshot.png b/screenshot.png
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