speice.io/katex/contrib/copy-tex.mjs

106 lines
3.6 KiB
JavaScript

// Set these to how you want inline and display math to be delimited.
var defaultCopyDelimiters = {
inline: ['$', '$'],
// alternative: ['\(', '\)']
display: ['$$', '$$'] // alternative: ['\[', '\]']
}; // Replace .katex elements with their TeX source (<annotation> element).
// Modifies fragment in-place. Useful for writing your own 'copy' handler,
// as in copy-tex.js.
function katexReplaceWithTex(fragment, copyDelimiters) {
if (copyDelimiters === void 0) {
copyDelimiters = defaultCopyDelimiters;
}
// Remove .katex-html blocks that are preceded by .katex-mathml blocks
// (which will get replaced below).
var katexHtml = fragment.querySelectorAll('.katex-mathml + .katex-html');
for (var i = 0; i < katexHtml.length; i++) {
var element = katexHtml[i];
if (element.remove) {
element.remove();
} else if (element.parentNode) {
element.parentNode.removeChild(element);
}
} // Replace .katex-mathml elements with their annotation (TeX source)
// descendant, with inline delimiters.
var katexMathml = fragment.querySelectorAll('.katex-mathml');
for (var _i = 0; _i < katexMathml.length; _i++) {
var _element = katexMathml[_i];
var texSource = _element.querySelector('annotation');
if (texSource) {
if (_element.replaceWith) {
_element.replaceWith(texSource);
} else if (_element.parentNode) {
_element.parentNode.replaceChild(texSource, _element);
}
texSource.innerHTML = copyDelimiters.inline[0] + texSource.innerHTML + copyDelimiters.inline[1];
}
} // Switch display math to display delimiters.
var displays = fragment.querySelectorAll('.katex-display annotation');
for (var _i2 = 0; _i2 < displays.length; _i2++) {
var _element2 = displays[_i2];
_element2.innerHTML = copyDelimiters.display[0] + _element2.innerHTML.substr(copyDelimiters.inline[0].length, _element2.innerHTML.length - copyDelimiters.inline[0].length - copyDelimiters.inline[1].length) + copyDelimiters.display[1];
}
return fragment;
}
function closestKatex(node) {
// If node is a Text Node, for example, go up to containing Element,
// where we can apply the `closest` method.
var element = node instanceof Element ? node : node.parentElement;
return element && element.closest('.katex');
} // Global copy handler to modify behavior on/within .katex elements.
document.addEventListener('copy', function (event) {
var selection = window.getSelection();
if (selection.isCollapsed || !event.clipboardData) {
return; // default action OK if selection is empty or unchangeable
}
var clipboardData = event.clipboardData;
var range = selection.getRangeAt(0); // When start point is within a formula, expand to entire formula.
var startKatex = closestKatex(range.startContainer);
if (startKatex) {
range.setStartBefore(startKatex);
} // Similarly, when end point is within a formula, expand to entire formula.
var endKatex = closestKatex(range.endContainer);
if (endKatex) {
range.setEndAfter(endKatex);
}
var fragment = range.cloneContents();
if (!fragment.querySelector('.katex-mathml')) {
return; // default action OK if no .katex-mathml elements
}
var htmlContents = Array.prototype.map.call(fragment.childNodes, el => el instanceof Text ? el.textContent : el.outerHTML).join(''); // Preserve usual HTML copy/paste behavior.
clipboardData.setData('text/html', htmlContents); // Rewrite plain-text version.
clipboardData.setData('text/plain', katexReplaceWithTex(fragment).textContent); // Prevent normal copy handling.
event.preventDefault();
});