mercurial/templates/static/mercurial.js

hgweb: calculate <canvas> width and height client-side

hgweb determines and passes to templates some variables related to graph
appearance, like bg_height, canvaswidth and canvasheight. bg_height was and
still is used for graph.scale() call in graph.tmpl, and the two latter
variables were used in <canvas> element as width and height properties, and
they were set before JS code got to run. Setting these properties server-side
doesn't make a lot of sense, because a graph that has been scaled should
calculate things like width and height on its own when being rendered.

Let's move (re)sizing <canvas> to JavaScript (to Graph.render function) and
stop parsing HTML with regular expressions just to know new width and height.
That extra loop that only counts cols is required because <canvas> can't
be resized after or in the process of rendering (or it gets cleared).
Incidentally, SVG doesn't have this problem and I'm hoping to switch graph to
using it in future.

There also was truecanvasheight, but according to hg grep --all it was never
used, see d490edc71146.

// mercurial.js - JavaScript utility functions
//
// Rendering of branch DAGs on the client side
// Display of elapsed time
// Show or hide diffstat
//
// Copyright 2008 Dirkjan Ochtman <dirkjan AT ochtman DOT nl>
// Copyright 2006 Alexander Schremmer <alex AT alexanderweb DOT de>
//
// derived from code written by Scott James Remnant <[e-mail]>
// Copyright 2005 Canonical Ltd.
//
// This software may be used and distributed according to the terms
// of the GNU General Public License, incorporated herein by reference.

var colors = [
	[ 1.0, 0.0, 0.0 ],
	[ 1.0, 1.0, 0.0 ],
	[ 0.0, 1.0, 0.0 ],
	[ 0.0, 1.0, 1.0 ],
	[ 0.0, 0.0, 1.0 ],
	[ 1.0, 0.0, 1.0 ]
];

function Graph() {

	this.canvas = document.getElementById('graph');
	if (window.G_vmlCanvasManager) this.canvas = window.G_vmlCanvasManager.initElement(this.canvas);
	this.ctx = this.canvas.getContext('2d');
	this.ctx.strokeStyle = 'rgb(0, 0, 0)';
	this.ctx.fillStyle = 'rgb(0, 0, 0)';
	this.bg = [0, 4];
	this.cell = [2, 0];
	this.columns = 0;

}

Graph.prototype = {
	reset: function() {
		this.bg = [0, 4];
		this.cell = [2, 0];
		this.columns = 0;
		document.getElementById('nodebgs').innerHTML = '';
		document.getElementById('graphnodes').innerHTML = '';
	},

	scale: function(height) {
		this.bg_height = height;
		this.box_size = Math.floor(this.bg_height / 1.2);
		this.cell_height = this.box_size;
	},

	setColor: function(color, bg, fg) {

		// Set the colour.
		//
		// If color is a string, expect an hexadecimal RGB
		// value and apply it unchanged. If color is a number,
		// pick a distinct colour based on an internal wheel;
		// the bg parameter provides the value that should be
		// assigned to the 'zero' colours and the fg parameter
		// provides the multiplier that should be applied to
		// the foreground colours.
		var s;
		if(typeof color === "string") {
			s = "#" + color;
		} else { //typeof color === "number"
			color %= colors.length;
			var red = (colors[color][0] * fg) || bg;
			var green = (colors[color][1] * fg) || bg;
			var blue = (colors[color][2] * fg) || bg;
			red = Math.round(red * 255);
			green = Math.round(green * 255);
			blue = Math.round(blue * 255);
			s = 'rgb(' + red + ', ' + green + ', ' + blue + ')';
		}
		this.ctx.strokeStyle = s;
		this.ctx.fillStyle = s;
		return s;

	},

	edge: function(x0, y0, x1, y1, color, width) {

		this.setColor(color, 0.0, 0.65);
		if(width >= 0)
			 this.ctx.lineWidth = width;
		this.ctx.beginPath();
		this.ctx.moveTo(x0, y0);
		this.ctx.lineTo(x1, y1);
		this.ctx.stroke();

	},

	vertex: function(x, y, radius, color, parity, cur) {
		this.ctx.beginPath();
		this.setColor(color, 0.25, 0.75);
		this.ctx.arc(x, y, radius, 0, Math.PI * 2, true);
		this.ctx.fill();

		var left = (this.bg_height - this.box_size) + (this.columns + 1) * this.box_size;
		var item = document.querySelector('[data-node="' + cur.node + '"]');
		if (item) {
			item.style.paddingLeft = left + 'px';
		}

		return ['', ''];
	},

	render: function(data) {

		var backgrounds = '';
		var nodedata = '';
		var i, j, cur, line, start, end, color, x, y, x0, y0, x1, y1, column, radius;

		var cols = 0;
		for (i = 0; i < data.length; i++) {
			cur = data[i];
			for (j = 0; j < cur.edges.length; j++) {
				line = cur.edges[j];
				cols = Math.max(cols, line[0], line[1]);
			}
		}
		this.canvas.width = (cols + 1) * this.bg_height;
		this.canvas.height = (data.length + 1) * this.bg_height - 27;

		for (i = 0; i < data.length; i++) {

			var parity = i % 2;
			this.cell[1] += this.bg_height;
			this.bg[1] += this.bg_height;

			cur = data[i];
			var fold = false;

			var prevWidth = this.ctx.lineWidth;
			for (j = 0; j < cur.edges.length; j++) {

				line = cur.edges[j];
				start = line[0];
				end = line[1];
				color = line[2];
				var width = line[3];
				if(width < 0)
					 width = prevWidth;
				var branchcolor = line[4];
				if(branchcolor)
					color = branchcolor;

				if (end > this.columns || start > this.columns) {
					this.columns += 1;
				}

				if (start === this.columns && start > end) {
					fold = true;
				}

				x0 = this.cell[0] + this.box_size * start + this.box_size / 2;
				y0 = this.bg[1] - this.bg_height / 2;
				x1 = this.cell[0] + this.box_size * end + this.box_size / 2;
				y1 = this.bg[1] + this.bg_height / 2;

				this.edge(x0, y0, x1, y1, color, width);

			}
			this.ctx.lineWidth = prevWidth;

			// Draw the revision node in the right column

			column = cur.vertex[0];
			color = cur.vertex[1];

			radius = this.box_size / 8;
			x = this.cell[0] + this.box_size * column + this.box_size / 2;
			y = this.bg[1] - this.bg_height / 2;
			var add = this.vertex(x, y, radius, color, parity, cur);
			backgrounds += add[0];
			nodedata += add[1];

			if (fold) this.columns -= 1;

		}

		document.getElementById('nodebgs').innerHTML += backgrounds;
		document.getElementById('graphnodes').innerHTML += nodedata;

	}

};


function process_dates(parentSelector){

	// derived from code from mercurial/templatefilter.py

	var scales = {
		'year':  365 * 24 * 60 * 60,
		'month':  30 * 24 * 60 * 60,
		'week':    7 * 24 * 60 * 60,
		'day':    24 * 60 * 60,
		'hour':   60 * 60,
		'minute': 60,
		'second': 1
	};

	function format(count, string){
		var ret = count + ' ' + string;
		if (count > 1){
			ret = ret + 's';
		}
 		return ret;
 	}

	function shortdate(date){
		var ret = date.getFullYear() + '-';
		// getMonth() gives a 0-11 result
		var month = date.getMonth() + 1;
		if (month <= 9){
			ret += '0' + month;
		} else {
			ret += month;
		}
		ret += '-';
		var day = date.getDate();
		if (day <= 9){
			ret += '0' + day;
		} else {
			ret += day;
		}
		return ret;
	}

 	function age(datestr){
 		var now = new Date();
 		var once = new Date(datestr);
		if (isNaN(once.getTime())){
			// parsing error
			return datestr;
		}

		var delta = Math.floor((now.getTime() - once.getTime()) / 1000);

		var future = false;
		if (delta < 0){
			future = true;
			delta = -delta;
			if (delta > (30 * scales.year)){
				return "in the distant future";
			}
		}

		if (delta > (2 * scales.year)){
			return shortdate(once);
		}

		for (var unit in scales){
			if (!scales.hasOwnProperty(unit)) { continue; }
			var s = scales[unit];
			var n = Math.floor(delta / s);
			if ((n >= 2) || (s === 1)){
				if (future){
					return format(n, unit) + ' from now';
				} else {
					return format(n, unit) + ' ago';
				}
			}
		}
	}

	var nodes = document.querySelectorAll((parentSelector || '') + ' .age');
	var dateclass = new RegExp('\\bdate\\b');
	for (var i=0; i<nodes.length; ++i){
		var node = nodes[i];
		var classes = node.className;
		var agevalue = age(node.textContent);
		if (dateclass.test(classes)){
			// We want both: date + (age)
			node.textContent += ' ('+agevalue+')';
		} else {
			node.title = node.textContent;
			node.textContent = agevalue;
		}
	}
}

function toggleDiffstat() {
    var curdetails = document.getElementById('diffstatdetails').style.display;
    var curexpand = curdetails === 'none' ? 'inline' : 'none';
    document.getElementById('diffstatdetails').style.display = curexpand;
    document.getElementById('diffstatexpand').style.display = curdetails;
}

function toggleLinewrap() {
    function getLinewrap() {
        var nodes = document.getElementsByClassName('sourcelines');
        // if there are no such nodes, error is thrown here
        return nodes[0].classList.contains('wrap');
    }

    function setLinewrap(enable) {
        var nodes = document.getElementsByClassName('sourcelines');
        var i;
        for (i = 0; i < nodes.length; i++) {
            if (enable) {
                nodes[i].classList.add('wrap');
            } else {
                nodes[i].classList.remove('wrap');
            }
        }

        var links = document.getElementsByClassName('linewraplink');
        for (i = 0; i < links.length; i++) {
            links[i].innerHTML = enable ? 'on' : 'off';
        }
    }

    setLinewrap(!getLinewrap());
}

function format(str, replacements) {
    return str.replace(/%(\w+)%/g, function(match, p1) {
        return String(replacements[p1]);
    });
}

function makeRequest(url, method, onstart, onsuccess, onerror, oncomplete) {
    var xhr = new XMLHttpRequest();
    xhr.onreadystatechange = function() {
        if (xhr.readyState === 4) {
            try {
                if (xhr.status === 200) {
                    onsuccess(xhr.responseText);
                } else {
                    throw 'server error';
                }
            } catch (e) {
                onerror(e);
            } finally {
                oncomplete();
            }
        }
    };

    xhr.open(method, url);
    xhr.overrideMimeType("text/xhtml; charset=" + document.characterSet.toLowerCase());
    xhr.send();
    onstart();
    return xhr;
}

function removeByClassName(className) {
    var nodes = document.getElementsByClassName(className);
    while (nodes.length) {
        nodes[0].parentNode.removeChild(nodes[0]);
    }
}

function docFromHTML(html) {
    var doc = document.implementation.createHTMLDocument('');
    doc.documentElement.innerHTML = html;
    return doc;
}

function appendFormatHTML(element, formatStr, replacements) {
    element.insertAdjacentHTML('beforeend', format(formatStr, replacements));
}

function adoptChildren(from, to) {
    var nodes = from.children;
    var curClass = 'c' + Date.now();
    while (nodes.length) {
        var node = nodes[0];
        node = document.adoptNode(node);
        node.classList.add(curClass);
        to.appendChild(node);
    }
    process_dates('.' + curClass);
}

function ajaxScrollInit(urlFormat,
                        nextPageVar,
                        nextPageVarGet,
                        containerSelector,
                        messageFormat,
                        mode) {
    var updateInitiated = false;
    var container = document.querySelector(containerSelector);

    function scrollHandler() {
        if (updateInitiated) {
            return;
        }

        var scrollHeight = document.documentElement.scrollHeight;
        var clientHeight = document.documentElement.clientHeight;
        var scrollTop = document.body.scrollTop || document.documentElement.scrollTop;

        if (scrollHeight - (scrollTop + clientHeight) < 50) {
            updateInitiated = true;
            removeByClassName('scroll-loading-error');
            container.lastElementChild.classList.add('scroll-separator');

            if (!nextPageVar) {
                var message = {
                    'class': 'scroll-loading-info',
                    text: 'No more entries'
                };
                appendFormatHTML(container, messageFormat, message);
                return;
            }

            makeRequest(
                format(urlFormat, {next: nextPageVar}),
                'GET',
                function onstart() {
                    var message = {
                        'class': 'scroll-loading',
                        text: 'Loading...'
                    };
                    appendFormatHTML(container, messageFormat, message);
                },
                function onsuccess(htmlText) {
                    var doc = docFromHTML(htmlText);

                    if (mode === 'graph') {
                        var graph = window.graph;
                        var dataStr = htmlText.match(/^\s*var data = (.*);$/m)[1];
                        var data = JSON.parse(dataStr);
                        if (data.length < nextPageVar) {
                            nextPageVar = undefined;
                        }
                        graph.reset();
                        adoptChildren(doc.querySelector('#graphnodes'), container.querySelector('#graphnodes'));
                        graph.render(data);
                    } else {
                        adoptChildren(doc.querySelector(containerSelector), container);
                    }

                    nextPageVar = nextPageVarGet(htmlText, nextPageVar);
                },
                function onerror(errorText) {
                    var message = {
                        'class': 'scroll-loading-error',
                        text: 'Error: ' + errorText
                    };
                    appendFormatHTML(container, messageFormat, message);
                },
                function oncomplete() {
                    removeByClassName('scroll-loading');
                    updateInitiated = false;
                    scrollHandler();
                }
            );
        }
    }

    window.addEventListener('scroll', scrollHandler);
    window.addEventListener('resize', scrollHandler);
    scrollHandler();
}

function renderDiffOptsForm() {
    // We use URLSearchParams for query string manipulation. Old browsers don't
    // support this API.
    if (!("URLSearchParams" in window)) {
        return;
    }

    var form = document.getElementById("diffopts-form");

    var KEYS = [
        "ignorews",
        "ignorewsamount",
        "ignorewseol",
        "ignoreblanklines",
    ];

    var urlParams = new window.URLSearchParams(window.location.search);

    function updateAndRefresh(e) {
        var checkbox = e.target;
        var name = checkbox.id.substr(0, checkbox.id.indexOf("-"));
        urlParams.set(name, checkbox.checked ? "1" : "0");
        window.location.search = urlParams.toString();
    }

    var allChecked = form.getAttribute("data-ignorews") === "1";

    for (var i = 0; i < KEYS.length; i++) {
        var key = KEYS[i];

        var checkbox = document.getElementById(key + "-checkbox");
        if (!checkbox) {
            continue;
        }

        var currentValue = form.getAttribute("data-" + key);
        checkbox.checked = currentValue !== "0";

        // ignorews implies ignorewsamount and ignorewseol.
        if (allChecked && (key === "ignorewsamount" || key === "ignorewseol")) {
            checkbox.checked = true;
            checkbox.disabled = true;
        }

        checkbox.addEventListener("change", updateAndRefresh, false);
    }

    form.style.display = 'block';
}

document.addEventListener('DOMContentLoaded', function() {
   process_dates();
}, false);