gitea/web_src/js/features/gitgraph.js

569 lines
17 KiB
JavaScript

// Although inspired by the https://github.com/bluef/gitgraph.js/blob/master/gitgraph.js
// this has been completely rewritten with almost no remaining code
// GitGraphCanvas is a canvas for drawing gitgraphs on to
class GitGraphCanvas {
constructor(canvas, widthUnits, heightUnits, config) {
this.ctx = canvas.getContext('2d');
const width = widthUnits * config.unitSize;
this.height = heightUnits * config.unitSize;
const ratio = window.devicePixelRatio || 1;
canvas.width = width * ratio;
canvas.height = this.height * ratio;
canvas.style.width = `${width}px`;
canvas.style.height = `${this.height}px`;
this.ctx.lineWidth = config.lineWidth;
this.ctx.lineJoin = 'round';
this.ctx.lineCap = 'round';
this.ctx.scale(ratio, ratio);
this.config = config;
}
drawLine(moveX, moveY, lineX, lineY, color) {
this.ctx.strokeStyle = color;
this.ctx.beginPath();
this.ctx.moveTo(moveX, moveY);
this.ctx.lineTo(lineX, lineY);
this.ctx.stroke();
}
drawLineRight(x, y, color) {
this.drawLine(
x - 0.5 * this.config.unitSize,
y + this.config.unitSize / 2,
x + 0.5 * this.config.unitSize,
y + this.config.unitSize / 2,
color
);
}
drawLineUp(x, y, color) {
this.drawLine(
x,
y + this.config.unitSize / 2,
x,
y - this.config.unitSize / 2,
color
);
}
drawNode(x, y, color) {
this.ctx.strokeStyle = color;
this.drawLineUp(x, y, color);
this.ctx.beginPath();
this.ctx.arc(x, y, this.config.nodeRadius, 0, Math.PI * 2, true);
this.ctx.fillStyle = color;
this.ctx.fill();
}
drawLineIn(x, y, color) {
this.drawLine(
x + 0.5 * this.config.unitSize,
y + this.config.unitSize / 2,
x - 0.5 * this.config.unitSize,
y - this.config.unitSize / 2,
color
);
}
drawLineOut(x, y, color) {
this.drawLine(
x - 0.5 * this.config.unitSize,
y + this.config.unitSize / 2,
x + 0.5 * this.config.unitSize,
y - this.config.unitSize / 2,
color
);
}
drawSymbol(symbol, columnNumber, rowNumber, color) {
const y = this.height - this.config.unitSize * (rowNumber + 0.5);
const x = this.config.unitSize * 0.5 * (columnNumber + 1);
switch (symbol) {
case '-':
if (columnNumber % 2 === 1) {
this.drawLineRight(x, y, color);
}
break;
case '_':
this.drawLineRight(x, y, color);
break;
case '*':
this.drawNode(x, y, color);
break;
case '|':
this.drawLineUp(x, y, color);
break;
case '/':
this.drawLineOut(x, y, color);
break;
case '\\':
this.drawLineIn(x, y, color);
break;
case '.':
case ' ':
break;
default:
console.error('Unknown symbol', symbol, color);
}
}
}
class GitGraph {
constructor(canvas, rawRows, config) {
this.rows = [];
let maxWidth = 0;
for (let i = 0; i < rawRows.length; i++) {
const rowStr = rawRows[i];
maxWidth = Math.max(rowStr.replace(/([_\s.-])/g, '').length, maxWidth);
const rowArray = rowStr.split('');
this.rows.unshift(rowArray);
}
this.currentFlows = [];
this.previousFlows = [];
this.gitGraphCanvas = new GitGraphCanvas(
canvas,
maxWidth,
this.rows.length,
config
);
}
generateNewFlow(column) {
let newId;
do {
newId = generateRandomColorString();
} while (this.hasFlow(newId, column));
return {id: newId, color: `#${newId}`};
}
hasFlow(id, column) {
// We want to find the flow with the current ID
// Possible flows are those in the currentFlows
// Or flows in previousFlows[column-2:...]
for (
let idx = column - 2 < 0 ? 0 : column - 2;
idx < this.previousFlows.length;
idx++
) {
if (this.previousFlows[idx] && this.previousFlows[idx].id === id) {
return true;
}
}
for (let idx = 0; idx < this.currentFlows.length; idx++) {
if (this.currentFlows[idx] && this.currentFlows[idx].id === id) {
return true;
}
}
return false;
}
takePreviousFlow(column) {
if (column < this.previousFlows.length && this.previousFlows[column]) {
const flow = this.previousFlows[column];
this.previousFlows[column] = null;
return flow;
}
return this.generateNewFlow(column);
}
draw() {
if (this.rows.length === 0) {
return;
}
this.currentFlows = new Array(this.rows[0].length);
// Generate flows for the first row - I do not believe that this can contain '_', '-', '.'
for (let column = 0; column < this.rows[0].length; column++) {
if (this.rows[0][column] === ' ') {
continue;
}
this.currentFlows[column] = this.generateNewFlow(column);
}
// Draw the first row
for (let column = 0; column < this.rows[0].length; column++) {
const symbol = this.rows[0][column];
const color = this.currentFlows[column] ? this.currentFlows[column].color : '';
this.gitGraphCanvas.drawSymbol(symbol, column, 0, color);
}
for (let row = 1; row < this.rows.length; row++) {
// Done previous row - step up the row
const currentRow = this.rows[row];
const previousRow = this.rows[row - 1];
this.previousFlows = this.currentFlows;
this.currentFlows = new Array(currentRow.length);
// Set flows for this row
for (let column = 0; column < currentRow.length; column++) {
column = this.setFlowFor(column, currentRow, previousRow);
}
// Draw this row
for (let column = 0; column < currentRow.length; column++) {
const symbol = currentRow[column];
const color = this.currentFlows[column] ? this.currentFlows[column].color : '';
this.gitGraphCanvas.drawSymbol(symbol, column, row, color);
}
}
}
setFlowFor(column, currentRow, previousRow) {
const symbol = currentRow[column];
switch (symbol) {
case '|':
case '*':
return this.setUpFlow(column, currentRow, previousRow);
case '/':
return this.setOutFlow(column, currentRow, previousRow);
case '\\':
return this.setInFlow(column, currentRow, previousRow);
case '_':
return this.setRightFlow(column, currentRow, previousRow);
case '-':
return this.setLeftFlow(column, currentRow, previousRow);
case ' ':
// In space no one can hear you flow ... (?)
return column;
default:
// Unexpected so let's generate a new flow and wait for bug-reports
this.currentFlows[column] = this.generateNewFlow(column);
return column;
}
}
// setUpFlow handles '|' or '*' - returns the last column that was set
// generally we prefer to take the left most flow from the previous row
setUpFlow(column, currentRow, previousRow) {
// If ' |/' or ' |_'
// '/|' '/|' -> Take the '|' flow directly beneath us
if (
column + 1 < currentRow.length &&
(currentRow[column + 1] === '/' || currentRow[column + 1] === '_') &&
column < previousRow.length &&
(previousRow[column] === '|' || previousRow[column] === '*') &&
previousRow[column - 1] === '/'
) {
this.currentFlows[column] = this.takePreviousFlow(column);
return column;
}
// If ' |/' or ' |_'
// '/ ' '/ ' -> Take the '/' flow from the preceding column
if (
column + 1 < currentRow.length &&
(currentRow[column + 1] === '/' || currentRow[column + 1] === '_') &&
column - 1 < previousRow.length &&
previousRow[column - 1] === '/'
) {
this.currentFlows[column] = this.takePreviousFlow(column - 1);
return column;
}
// If ' |'
// '/' -> Take the '/' flow - (we always prefer the left-most flow)
if (
column > 0 &&
column - 1 < previousRow.length &&
previousRow[column - 1] === '/'
) {
this.currentFlows[column] = this.takePreviousFlow(column - 1);
return column;
}
// If '|' OR '|' take the '|' flow
// '|' '*'
if (
column < previousRow.length &&
(previousRow[column] === '|' || previousRow[column] === '*')
) {
this.currentFlows[column] = this.takePreviousFlow(column);
return column;
}
// If '| ' keep the '\' flow
// ' \'
if (column + 1 < previousRow.length && previousRow[column + 1] === '\\') {
this.currentFlows[column] = this.takePreviousFlow(column + 1);
return column;
}
// Otherwise just create a new flow - probably this is an error...
this.currentFlows[column] = this.generateNewFlow(column);
return column;
}
// setOutFlow handles '/' - returns the last column that was set
// generally we prefer to take the left most flow from the previous row
setOutFlow(column, currentRow, previousRow) {
// If '_/' -> keep the '_' flow
if (column > 0 && currentRow[column - 1] === '_') {
this.currentFlows[column] = this.currentFlows[column - 1];
return column;
}
// If '_|/' -> keep the '_' flow
if (
column > 1 &&
(currentRow[column - 1] === '|' || currentRow[column - 1] === '*') &&
currentRow[column - 2] === '_'
) {
this.currentFlows[column] = this.currentFlows[column - 2];
return column;
}
// If '|/'
// '/' -> take the '/' flow (if it is still available)
if (
column > 1 &&
currentRow[column - 1] === '|' &&
column - 2 < previousRow.length &&
previousRow[column - 2] === '/'
) {
this.currentFlows[column] = this.takePreviousFlow(column - 2);
return column;
}
// If ' /'
// '/' -> take the '/' flow, but transform the symbol to '|' due to our spacing
// This should only happen if there are 3 '/' - in a row so we don't need to be cleverer here
if (
column > 0 &&
currentRow[column - 1] === ' ' &&
column - 1 < previousRow.length &&
previousRow[column - 1] === '/'
) {
this.currentFlows[column] = this.takePreviousFlow(column - 1);
currentRow[column] = '|';
return column;
}
// If ' /'
// '|' -> take the '|' flow
if (
column > 0 &&
currentRow[column - 1] === ' ' &&
column - 1 < previousRow.length &&
(previousRow[column - 1] === '|' || previousRow[column - 1] === '*')
) {
this.currentFlows[column] = this.takePreviousFlow(column - 1);
return column;
}
// If '/' <- Not sure this ever happens... but take the '\' flow
// '\'
if (column < previousRow.length && previousRow[column] === '\\') {
this.currentFlows[column] = this.takePreviousFlow(column);
return column;
}
// Otherwise just generate a new flow and wait for bug-reports...
this.currentFlows[column] = this.generateNewFlow(column);
return column;
}
// setInFlow handles '\' - returns the last column that was set
// generally we prefer to take the left most flow from the previous row
setInFlow(column, currentRow, previousRow) {
// If '\?'
// '/?' -> take the '/' flow
if (column < previousRow.length && previousRow[column] === '/') {
this.currentFlows[column] = this.takePreviousFlow(column);
return column;
}
// If '\?'
// ' \' -> take the '\' flow and reassign to '|'
// This should only happen if there are 3 '\' - in a row so we don't need to be cleverer here
if (column + 1 < previousRow.length && previousRow[column + 1] === '\\') {
this.currentFlows[column] = this.takePreviousFlow(column + 1);
currentRow[column] = '|';
return column;
}
// If '\?'
// ' |' -> take the '|' flow
if (
column + 1 < previousRow.length &&
(previousRow[column + 1] === '|' || previousRow[column + 1] === '*')
) {
this.currentFlows[column] = this.takePreviousFlow(column + 1);
return column;
}
// Otherwise just generate a new flow and wait for bug-reports if we're wrong...
this.currentFlows[column] = this.generateNewFlow(column);
return column;
}
// setRightFlow handles '_' - returns the last column that was set
// generally we prefer to take the left most flow from the previous row
setRightFlow(column, currentRow, previousRow) {
// if '__' keep the '_' flow
if (column > 0 && currentRow[column - 1] === '_') {
this.currentFlows[column] = this.currentFlows[column - 1];
return column;
}
// if '_|_' -> keep the '_' flow
if (
column > 1 &&
currentRow[column - 1] === '|' &&
currentRow[column - 2] === '_'
) {
this.currentFlows[column] = this.currentFlows[column - 2];
return column;
}
// if ' _' -> take the '/' flow
// '/ '
if (
column > 0 &&
column - 1 < previousRow.length &&
previousRow[column - 1] === '/'
) {
this.currentFlows[column] = this.takePreviousFlow(column - 1);
return column;
}
// if ' |_'
// '/? ' -> take the '/' flow (this may cause generation...)
// we can do this because we know that git graph
// doesn't create compact graphs like: ' |_'
// '//'
if (
column > 1 &&
column - 2 < previousRow.length &&
previousRow[column - 2] === '/'
) {
this.currentFlows[column] = this.takePreviousFlow(column - 2);
return column;
}
// There really shouldn't be another way of doing this - generate and wait for bug-reports...
this.currentFlows[column] = this.generateNewFlow(column);
return column;
}
// setLeftFlow handles '----.' - returns the last column that was set
// generally we prefer to take the left most flow from the previous row that terminates this left recursion
setLeftFlow(column, currentRow, previousRow) {
// This is: '----------.' or the like
// ' \ \ /|\'
// Find the end of the '-' or nearest '/|\' in the previousRow :
let originalColumn = column;
let flow;
for (; column < currentRow.length && currentRow[column] === '-'; column++) {
if (column > 0 && column - 1 < previousRow.length && previousRow[column - 1] === '/') {
flow = this.takePreviousFlow(column - 1);
break;
} else if (column < previousRow.length && previousRow[column] === '|') {
flow = this.takePreviousFlow(column);
break;
} else if (
column + 1 < previousRow.length &&
previousRow[column + 1] === '\\'
) {
flow = this.takePreviousFlow(column + 1);
break;
}
}
// if we have a flow then we found a '/|\' in the previousRow
if (flow) {
for (; originalColumn < column + 1; originalColumn++) {
this.currentFlows[originalColumn] = flow;
}
return column;
}
// If the symbol in the column is not a '.' then there's likely an error
if (currentRow[column] !== '.') {
// It really should end in a '.' but this one doesn't...
// 1. Step back - we don't want to eat this column
column--;
// 2. Generate a new flow and await bug-reports...
this.currentFlows[column] = this.generateNewFlow(column);
// 3. Assign all of the '-' to the same flow.
for (; originalColumn < column; originalColumn++) {
this.currentFlows[originalColumn] = this.currentFlows[column];
}
return column;
}
// We have a terminal '.' eg. the current row looks like '----.'
// the previous row should look like one of '/|\' eg. ' \'
if (column > 0 && column - 1 < previousRow.length && previousRow[column - 1] === '/') {
flow = this.takePreviousFlow(column - 1);
} else if (column < previousRow.length && previousRow[column] === '|') {
flow = this.takePreviousFlow(column);
} else if (
column + 1 < previousRow.length &&
previousRow[column + 1] === '\\'
) {
flow = this.takePreviousFlow(column + 1);
} else {
// Again unexpected so let's generate and wait the bug-report
flow = this.generateNewFlow(column);
}
// Assign all of the rest of the ----. to this flow.
for (; originalColumn < column + 1; originalColumn++) {
this.currentFlows[originalColumn] = flow;
}
return column;
}
}
function generateRandomColorString() {
const chars = '0123456789ABCDEF';
const stringLength = 6;
let randomString = '',
rnum,
i;
for (i = 0; i < stringLength; i++) {
rnum = Math.floor(Math.random() * chars.length);
randomString += chars.substring(rnum, rnum + 1);
}
return randomString;
}
export default async function initGitGraph() {
const graphCanvas = document.getElementById('graph-canvas');
if (!graphCanvas || !graphCanvas.getContext) return;
// Grab the raw graphList
const graphList = [];
$('#graph-raw-list li span.node-relation').each(function () {
graphList.push($(this).text());
});
// Define some drawing parameters
const config = {
unitSize: 20,
lineWidth: 3,
nodeRadius: 4
};
const gitGraph = new GitGraph(graphCanvas, graphList, config);
gitGraph.draw();
graphCanvas.closest('#git-graph-container').classList.add('in');
}