Stackedit/js/mathjax-editing.js
2013-05-13 00:59:17 +01:00

253 lines
7.3 KiB
JavaScript

define([ "../lib/MathJax/MathJax" ], function() {
MathJax.Hub.Config({"HTML-CSS": {preferredFont: "TeX",availableFonts: ["STIX", "TeX"],linebreaks: {automatic: true},EqnChunk: (MathJax.Hub.Browser.isMobile ? 10 : 50), imageFont: null},
tex2jax: {inlineMath: [["$", "$"], ["\\\\(", "\\\\)"]],displayMath: [["$$", "$$"], ["\\[", "\\]"]],processEscapes: true,ignoreClass: "tex2jax_ignore|dno"},
TeX: {noUndefined: {attributes: {mathcolor: "red",mathbackground: "#FFEEEE",mathsize: "90%"}},
Safe: {allow: {URLs: "safe",classes: "safe",cssIDs: "safe",styles: "safe",fontsize: "all"}}},
messageStyle: "none"
});
var ready = false; // true after initial typeset is complete
var pending = false; // true when MathJax has been requested
var preview = null; // the preview container
var inline = "$"; // the inline math delimiter
var blocks, start, end, last, braces; // used in searching for math
var math; // stores math until markdone is done
var HUB = MathJax.Hub;
//
// Runs after initial typeset
//
HUB.Queue(function() {
ready = true;
HUB.processUpdateTime = 50; // reduce update time so that we can cancel
// easier
HUB.Config({ "HTML-CSS" : { EqnChunk : 10, EqnChunkFactor : 1 }, // reduce
// chunk
// for
// more
// frequent
// updates
SVG : { EqnChunk : 10, EqnChunkFactor : 1 } });
});
//
// The pattern for math delimiters and special symbols
// needed for searching for math in the page.
//
var SPLIT = /(\$\$?|\\(?:begin|end)\{[a-z]*\*?\}|\\[\\{}$]|[{}]|(?:\n\s*)+|@@\d+@@)/i;
//
// The math is in blocks i through j, so
// collect it into one block and clear the others.
// Replace &, <, and > by named entities.
// For IE, put <br> at the ends of comments since IE removes \n.
// Clear the current math positions and store the index of the
// math, then push the math string onto the storage array.
//
function processMath(i, j) {
var block = blocks.slice(i, j + 1).join("").replace(/&/g, "&amp;") // use
// HTML
// entity
// for
// &
.replace(/</g, "&lt;") // use HTML entity for <
.replace(/>/g, "&gt;") // use HTML entity for >
;
if (HUB.Browser.isMSIE) {
block = block.replace(/(%[^\n]*)\n/g, "$1<br/>\n")
}
while (j > i) {
blocks[j] = "";
j--
}
blocks[i] = "@@" + math.length + "@@";
math.push(block);
start = end = last = null;
}
//
// Break up the text into its component parts and search
// through them for math delimiters, braces, linebreaks, etc.
// Math delimiters must match and braces must balance.
// Don't allow math to pass through a double linebreak
// (which will be a paragraph).
//
function removeMath(text) {
start = end = last = null; // for tracking math delimiters
math = []; // stores math strings for latter
blocks = text.replace(/\r\n?/g, "\n").split(SPLIT);
for ( var i = 1, m = blocks.length; i < m; i += 2) {
var block = blocks[i];
if (block.charAt(0) === "@") {
//
// Things that look like our math markers will get
// stored and then retrieved along with the math.
//
blocks[i] = "@@" + math.length + "@@";
math.push(block);
} else if (start) {
//
// If we are in math, look for the end delimiter,
// but don't go past double line breaks, and
// and balance braces within the math.
//
if (block === end) {
if (braces) {
last = i
} else {
processMath(start, i)
}
} else if (block.match(/\n.*\n/)) {
if (last) {
i = last;
processMath(start, i)
}
start = end = last = null;
braces = 0;
} else if (block === "{") {
braces++
} else if (block === "}" && braces) {
braces--
}
} else {
//
// Look for math start delimiters and when
// found, set up the end delimiter.
//
if (block === inline || block === "$$") {
start = i;
end = block;
braces = 0;
} else if (block.substr(1, 5) === "begin") {
start = i;
end = "\\end" + block.substr(6);
braces = 0;
}
}
}
if (last) {
processMath(start, last)
}
return blocks.join("");
}
//
// Put back the math strings that were saved,
// and clear the math array (no need to keep it around).
//
function replaceMath(text) {
text = text.replace(/@@(\d+)@@/g, function(match, n) {
return math[n]
});
math = null;
return text;
}
//
// This is run to restart MathJax after it has finished
// the previous run (that may have been canceled)
//
var refreshCallback = undefined;
function RestartMJ() {
pending = false;
HUB.cancelTypeset = false; // won't need to do this in the future
HUB.Queue([ "Typeset", HUB, preview ]);
HUB.Queue(refreshCallback);
}
//
// When the preview changes, cancel MathJax and restart,
// if we haven't done that already.
//
function UpdateMJ() {
if (!pending && ready) {
pending = true;
HUB.Cancel();
HUB.Queue(RestartMJ);
}
}
//
// Save the preview ID and the inline math delimiter.
// Create a converter for the editor and register a preConversion hook
// to handle escaping the math.
// Create a preview refresh hook to handle starting MathJax.
//
function prepareWmdForMathJax(editorObject, delimiters, callback) {
refreshCallback = callback;
preview = document.getElementById("wmd-preview");
inline = delimiters[0][0];
var converterObject = editorObject.getConverter();
converterObject.hooks.chain("preConversion", removeMath);
converterObject.hooks.chain("postConversion", replaceMath);
editorObject.hooks.chain("onPreviewRefresh", UpdateMJ);
}
//
// Set up MathJax to allow canceling of typesetting, if it
// doesn't already have that.
//
if (!HUB.Cancel) {
HUB.cancelTypeset = false;
var CANCELMESSAGE = "MathJax Canceled";
HUB.Register
.StartupHook(
"HTML-CSS Jax Config",
function() {
var HTMLCSS = MathJax.OutputJax["HTML-CSS"], TRANSLATE = HTMLCSS.Translate;
HTMLCSS.Augment({ Translate : function(script, state) {
if (HUB.cancelTypeset || state.cancelled) {
throw Error(CANCELMESSAGE)
}
return TRANSLATE.call(HTMLCSS, script, state);
} });
});
HUB.Register.StartupHook("SVG Jax Config", function() {
var SVG = MathJax.OutputJax["SVG"], TRANSLATE = SVG.Translate;
SVG.Augment({ Translate : function(script, state) {
if (HUB.cancelTypeset || state.cancelled) {
throw Error(CANCELMESSAGE)
}
return TRANSLATE.call(SVG, script, state);
} });
});
HUB.Register.StartupHook("TeX Jax Config", function() {
var TEX = MathJax.InputJax.TeX, TRANSLATE = TEX.Translate;
TEX.Augment({ Translate : function(script, state) {
if (HUB.cancelTypeset || state.cancelled) {
throw Error(CANCELMESSAGE)
}
return TRANSLATE.call(TEX, script, state);
} });
});
var PROCESSERROR = HUB.processError;
HUB.processError = function(error, state, type) {
if (error.message !== CANCELMESSAGE) {
return PROCESSERROR.call(HUB, error, state, type)
}
MathJax.Message.Clear(0, 0);
state.jaxIDs = [];
state.jax = {};
state.scripts = [];
state.i = state.j = 0;
state.cancelled = true;
return null;
};
HUB.Cancel = function() {
this.cancelTypeset = true
};
}
return { prepareWmdForMathJax : prepareWmdForMathJax };
});