frontend/index.js

   1 const sleep = (ms) => new Promise(resolve => setTimeout(resolve, ms));
   2
   3 /**
   4  * Safari iOS pls
   5  */
   6 const formSubmitPolyfill = (form, callback) => {
   7     if (form.requestSubmit) {
   8         form.requestSubmit();
   9     } else {
  10         callback();
  11     }
  12 }
  13
  14 const createGenreListWithClickEvent = (genreList, genres, callback) => {
  15     genreList.append(...genres.map((genre) => {
  16         const name = genre["name"];
  17         const li = document.createElement("li");
  18         li.setAttribute("data-name", name);
  19         li.addEventListener("click", callback);
  20         li.appendChild(document.createTextNode(name));
  21         return li;
  22     }));
  23 }
  24
  25 const relativeToCtx = (x1, x2, y1, y2, ctx) => {
  26     const newX = x1 + x2;
  27     const newY = y1 + y2;
  28     ctx.lineTo(newX, newY);
  29     return [newX, newY];
  30 }
  31
  32 /**
  33  * Return (x,y) of canvas
  34  */
  35 const getDimensions = (canvas) => [canvas.width, canvas.height];
  36
  37 /**
  38  * Return (x,y) midpoint of canvas
  39  */
  40 const getCenter = (canvas) => getDimensions(canvas).map((dim) => dim / 2);
  41
  42 const getRectangleDimensionsUnbound = (canvas, xScale, yScale) => {
  43     [width, height] = getDimensions(canvas);
  44     return [width * xScale, height * yScale];
  45 }
  46
  47 const getRectangleDimensions = (canvas) => getRectangleDimensionsUnbound(canvas, .5, .1);
  48
  49 /**
  50  * Draw champion box and clear background.
  51  */
  52 const drawWinner = (canvas) => {
  53     const ctx = canvas.getContext("2d");
  54     const [width, height] = getDimensions(canvas);
  55     const [mid_x, mid_y] = getCenter(canvas);
  56     const [rect_width, rect_height] = getRectangleDimensions(canvas);
  57     ctx.strokeRect(mid_x - rect_width / 2, mid_y - rect_height / 2, rect_width, rect_height);
  58     ctx.clearRect(mid_x - rect_width / 2, mid_y - rect_height / 2, rect_width, rect_height);
  59 }
  60
  61 /**
  62  * Draws a path in context from the current location to a point xDist * left, yDist * up away from it.
  63  * @param ctx RenderingContext
  64  * @param x, y float current location
  65  * @param x, y float distance away
  66  * @param up, left (-1|1) directions
  67  * @return [newNodeX, newNodeY]
  68  */
  69 const drawBranchFrom = (ctx, x, y, xDist, yDist, left, up) => {
  70     const newX = x + (xDist * left)
  71     const newY = y + (yDist * up)
  72     ctx.lineTo(x, newY);
  73     ctx.lineTo(newX, newY);
  74     ctx.stroke();
  75     return [newX, newY];
  76 }
  77
  78 const drawArtistOnCtx = (ctx, artistName, x, y) => {
  79     ctx.font = "1em sans serif";
  80     ctx.strokeText(artistName, x, y);
  81 }
  82
  83 /**
  84  * Draws paths to the terminal nodes of a round
  85  * @param x, y the point representation of the start of the branch
  86  * @param baseCallback a callback that needs the terminal x,y context
  87  */
  88 const drawMatchup = (canvas, x, y, iter, maxIter, left, artists, baseCallback) => {
  89     if (iter === maxIter) {
  90         return baseCallback(x, y);
  91     }
  92     const ctx =  canvas.getContext("2d");
  93     ctx.direction = left === -1 ? "ltr" : "rtl";
  94     const [width, height] = getDimensions(canvas);
  95
  96     const drawBranchUp = (xDist, yDist) => drawBranchFrom(ctx, x, y, xDist, yDist, left, -1);
  97     const drawBranchDown = (xDist, yDist) => drawBranchFrom(ctx, x, y, xDist, yDist, left, 1);
  98     const drawArtist = (artistName, x, y) => drawArtistOnCtx(ctx, artistName, x, y);
  99     const drawArtist1 = (x, y) => drawArtist(artists.shift()["name"], x, y);
 100     const drawArtist2 = (x, y) => drawArtist(artists.pop()["name"], x, y);
 101
 102     ctx.beginPath();
 103     ctx.moveTo(x, y);
 104     const branchDistances = [width / (5 * (iter + 1)), height / (9 * (iter + 1))];
 105     drawMatchup(
 106         canvas,
 107         ...drawBranchUp(...branchDistances),
 108         iter + 1,
 109         maxIter,
 110         left,
 111         artists,
 112         drawArtist1,
 113     );
 114
 115     ctx.moveTo(x, y);
 116     drawMatchup(
 117         canvas,
 118         ...drawBranchDown(...branchDistances),
 119         iter + 1,
 120         maxIter,
 121         left,
 122         artists,
 123         drawArtist2,
 124     );
 125 }
 126
 127 const drawBracket = (canvas, artists) => {
 128     const context = canvas.getContext("2d").clearRect(0, 0, canvas.width, canvas.height);
 129     drawWinner(canvas);
 130     const [mid_x, mid_y] = getCenter(canvas);
 131     const [rect_width, rect_height] = getRectangleDimensions(canvas);
 132     const groups = 4;
 133     const rounds = Math.floor(Math.log2(artists.length / groups));
 134     for (let group = 1; group <= groups; group++) {
 135             drawMatchup(
 136                 canvas,
 137                 mid_x + (Math.pow(-1, group) * (rect_width / 4)),
 138                 mid_y + (Math.pow(-1, Math.floor(group / 2)) * (rect_height * 2)),
 139                 0,
 140                 rounds,
 141                 Math.pow(-1, group),
 142                 artists,
 143                 (x, y) => console.log("hello")
 144             );
 145     }
 146 }
 147
 148 window.onload = () => {
 149     const lStorage = window.localStorage;
 150     const genreList = document.getElementById("genre-list");
 151     const genreInput = document.getElementById("genre-input");
 152     const genreForm = document.getElementById("genre-form");
 153     const canvas = document.getElementById("bracket");
 154
 155     const formSubmitAction = () => {
 156         fetch(encodeURI(`http://localhost:8080/artist/genre?genre_name=${genreInput.value}`))
 157         .then((response) => response.json())
 158         .then((data) => drawBracket(canvas, data.slice(0, 33)));
 159     }
 160
 161     const createGenreList = (genreList, genres) => {
 162         return createGenreListWithClickEvent(genreList, genres, (e) => {
 163             genreInput.value = e.target.innerText;
 164             formSubmitPolyfill(genreForm, formSubmitAction);
 165         })
 166     }
 167     let genres = JSON.parse(lStorage.getItem("genres"))
 168     if (genres === null) {
 169         fetch("http://localhost:8080/genre")
 170             .then((response) => response.text())
 171             .then((text) => {
 172                 window.localStorage.setItem("genres", text);
 173                 genres = JSON.parse(text);
 174                 createGenreList(genreList, genres);
 175             });
 176     } else {
 177         createGenreList(genreList, genres);
 178     }
 179
 180     genreForm.addEventListener("submit", (e) => {
 181         e.preventDefault();
 182         formSubmitAction()
 183     });
 184
 185     genreInput.addEventListener("input", (e) => {
 186         const input = e.target;
 187         Array.from(genreList.children).forEach((item) => item.style.display= item.dataset.name.includes(input.value.toLowerCase()) ? "block" : "none");
 188     });
 189     genreInput.addEventListener("focus", (e) => {
 190         genreList.style.display = "block";
 191     });
 192     genreInput.addEventListener("blur", (e) => {
 193         sleep(150).then(() => genreList.style.display = "none");
 194     });
 195
 196
 197     canvas.width = window.innerWidth;
 198     canvas.height = window.innerHeight;
 199     drawBracket(canvas, ['dummy', 'dummy', 'dum' ,'dumhy']);
 200
 201     const bgImg = new Image();
 202     bgImg.onload = () => {
 203         const ctx = canvas.getContext("2d");
 204         //ctx.mozImageSmoothingEnabled = false;
 205         //ctx.webkitImageSmoothingEnabled = false;
 206         //ctx.msImageSmoothingEnabled = false;
 207         //ctx.imageSmoothingEnabled = false;
 208         ctx.drawImage(
 209             bgImg,
 210             0,
 211             0,
 212             (canvas.width / bgImg.width) * bgImg.width,
 213             (canvas.height / bgImg.height) * bgImg.height
 214         );
 215     }
 216
 217     const upload = document.getElementById("image-upload");
 218     upload.addEventListener("change", (e) => {
 219         bgImg.src = URL.createObjectURL(e.target.files[0]);
 220     });
 221 }