view mercurial/templates/static/mercurial.js @ 30308:d500ddae7494

bdiff: don't check border condition in loop

`plast = a + len - 1`. So, this "for" loop iterates from "a" to "plast",
inclusive. So, `p == plast` can only be true on the final iteration
of the loop. So checking for it on every loop iteration is wasteful.

This patch simply decreases the upper bound of the loop by 1 and
adds an explicit check after iteration for the `p == plast` case.
We can't simply add 1 to the initial value for "i" because that
doesn't do the correct thing on empty input strings.

`perfbdiff -m 3041e4d59df2` on the Firefox repo becomes significantly
faster:

! wall 0.072763 comb 0.070000 user 0.070000 sys 0.000000 (best of 100)
! wall 0.053221 comb 0.060000 user 0.060000 sys 0.000000 (best of 100)

For the curious, this code has its origins in 8b067bde6679, which is
the changeset that introduced bdiff.c in 2005.

Also, GNU diffutils is able to perform a similar line-based diff in
under 20ms. So there's likely more perf wins to be found in this code.
One of them is the hashing algorithm. But it looks like mpm spent
some time testing hash collisions in d0c48891dd4a. I'd like to do the
same before switching away from lyhash, just to be on the safe side.

// 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.cur = [0, 0];
	this.line_width = 3;
	this.bg = [0, 4];
	this.cell = [2, 0];
	this.columns = 0;
	this.revlink = '';

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

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

	this.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;

	}

	this.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();

	}

	this.render = function(data) {

		var backgrounds = '';
		var nodedata = '';

		for (var i in data) {

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

			var cur = data[i];
			var node = cur[1];
			var edges = cur[2];
			var fold = false;

			var prevWidth = this.ctx.lineWidth;
			for (var j in edges) {

				line = 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) {
					var 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 = node[0]
			color = node[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, 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 (unit in scales){
			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');
        for (var 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 (var 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) {
    xfr = new XMLHttpRequest();
    xfr.onreadystatechange = function() {
        if (xfr.readyState === 4) {
            try {
                if (xfr.status === 200) {
                    onsuccess(xfr.responseText);
                } else {
                    throw 'server error';
                }
            } catch (e) {
                onerror(e);
            } finally {
                oncomplete();
            }
        }
    };

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

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 ajaxScrollInit(urlFormat,
                        nextPageVar,
                        nextPageVarGet,
                        containerSelector,
                        messageFormat,
                        mode) {
    updateInitiated = false;
    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) {
                    if (mode == 'graph') {
                        var sizes = htmlText.match(/^\s*<canvas id="graph" width="(\d+)" height="(\d+)"><\/canvas>$/m);
                        var addWidth = sizes[1];
                        var addHeight = sizes[2];
                        addWidth = parseInt(addWidth);
                        addHeight = parseInt(addHeight);
                        graph.canvas.width = addWidth;
                        graph.canvas.height = addHeight;

                        var dataStr = htmlText.match(/^\s*var data = (.*);$/m)[1];
                        var data = JSON.parse(dataStr);
                        if (data.length < nextPageVar) {
                            nextPageVar = undefined;
                        }
                        graph.reset();
                        graph.render(data);
                    } else {
                        var doc = docFromHTML(htmlText);
                        var nodes = doc.querySelector(containerSelector).children;
                        var curClass = 'c' + Date.now();
                        while (nodes.length) {
                            var node = nodes[0];
                            node = document.adoptNode(node);
                            node.classList.add(curClass);
                            container.appendChild(node);
                        }
                        process_dates('.' + curClass);
                    }

                    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();
}