build/plugins/anchors.html
<!-- anchors plugin -->
<script>
(function() {
// /////////////////////////
// DESCRIPTION
// /////////////////////////
// This Manubot plugin adds an anchor next to each of a certain type
// of element that provides a human-readable url to that specific
// item/position in the document (eg "manuscript.html#abstract"). It
// also makes it such that scrolling out of view of a target removes
// its identifier from the url.
// /////////////////////////
// OPTIONS
// /////////////////////////
// plugin name prefix for url parameters
const pluginName = 'anchors';
// default plugin options
const options = {
// which types of elements to add anchors next to, in
// "document.querySelector" format
typesQuery: 'h1, h2, h3, [id^="fig:"], [id^="tbl:"], [id^="eq:"]',
// whether plugin is on or not
enabled: 'true'
};
// change options above, or override with url parameter, eg:
// 'manuscript.html?pluginName-enabled=false'
// /////////////////////////
// SCRIPT
// /////////////////////////
// start script
function start() {
// add anchor to each element of specified types
const elements = document.querySelectorAll(options.typesQuery);
for (const element of elements)
addAnchor(element);
// attach scroll listener to window
window.addEventListener('scroll', onScroll);
}
// when window is scrolled
function onScroll() {
// if url has hash and user has scrolled out of view of hash
// target, remove hash from url
const tolerance = 100;
const target = getHashTarget();
if (target) {
if (
target.getBoundingClientRect().top >
window.innerHeight + tolerance ||
target.getBoundingClientRect().bottom < 0 - tolerance
)
history.pushState(null, null, ' ');
}
}
// add anchor to element
function addAnchor(element) {
let addTo; // element to add anchor button to
// if figure or table, modify withId and addTo to get expected
// elements
if (element.id.indexOf('fig:') === 0) {
addTo = element.querySelector('figcaption');
} else if (element.id.indexOf('tbl:') === 0) {
addTo = element.querySelector('caption');
} else if (element.id.indexOf('eq:') === 0) {
addTo = element.querySelector('.eqnos-number');
}
addTo = addTo || element;
const id = element.id || null;
// do not add anchor if element doesn't have assigned id.
// id is generated by pandoc and is assumed to be unique and
// human-readable
if (!id)
return;
// create anchor button
const anchor = document.createElement('a');
anchor.innerHTML = document.querySelector('.icon_link').innerHTML;
anchor.title = 'Link to this part of the document';
anchor.classList.add('icon_button', 'anchor');
anchor.dataset.ignore = 'true';
anchor.href = '#' + id;
addTo.appendChild(anchor);
}
// get element that is target of link or url hash
function getHashTarget() {
const hash = window.location.hash;
const id = hash.slice(1);
let target = document.querySelector('[id="' + id + '"]');
if (!target)
return;
// if figure or table, modify target to get expected element
if (id.indexOf('fig:') === 0)
target = target.querySelector('figure');
if (id.indexOf('tbl:') === 0)
target = target.querySelector('table');
return target;
}
// load options from url parameters
function loadOptions() {
const url = window.location.search;
const params = new URLSearchParams(url);
for (const optionName of Object.keys(options)) {
const paramName = pluginName + '-' + optionName;
const param = params.get(paramName);
if (param !== '' && param !== null)
options[optionName] = param;
}
}
loadOptions();
// start script when document is finished loading
if (options.enabled === 'true')
window.addEventListener('load', start);
})();
</script>
<!-- link icon -->
<template class="icon_link">
<!-- modified from: https://fontawesome.com/icons/link -->
<svg width="16" height="16" viewBox="0 0 512 512">
<path
fill="currentColor"
d="M326.612 185.391c59.747 59.809 58.927 155.698.36 214.59-.11.12-.24.25-.36.37l-67.2 67.2c-59.27 59.27-155.699 59.262-214.96 0-59.27-59.26-59.27-155.7 0-214.96l37.106-37.106c9.84-9.84 26.786-3.3 27.294 10.606.648 17.722 3.826 35.527 9.69 52.721 1.986 5.822.567 12.262-3.783 16.612l-13.087 13.087c-28.026 28.026-28.905 73.66-1.155 101.96 28.024 28.579 74.086 28.749 102.325.51l67.2-67.19c28.191-28.191 28.073-73.757 0-101.83-3.701-3.694-7.429-6.564-10.341-8.569a16.037 16.037 0 0 1-6.947-12.606c-.396-10.567 3.348-21.456 11.698-29.806l21.054-21.055c5.521-5.521 14.182-6.199 20.584-1.731a152.482 152.482 0 0 1 20.522 17.197zM467.547 44.449c-59.261-59.262-155.69-59.27-214.96 0l-67.2 67.2c-.12.12-.25.25-.36.37-58.566 58.892-59.387 154.781.36 214.59a152.454 152.454 0 0 0 20.521 17.196c6.402 4.468 15.064 3.789 20.584-1.731l21.054-21.055c8.35-8.35 12.094-19.239 11.698-29.806a16.037 16.037 0 0 0-6.947-12.606c-2.912-2.005-6.64-4.875-10.341-8.569-28.073-28.073-28.191-73.639 0-101.83l67.2-67.19c28.239-28.239 74.3-28.069 102.325.51 27.75 28.3 26.872 73.934-1.155 101.96l-13.087 13.087c-4.35 4.35-5.769 10.79-3.783 16.612 5.864 17.194 9.042 34.999 9.69 52.721.509 13.906 17.454 20.446 27.294 10.606l37.106-37.106c59.271-59.259 59.271-155.699.001-214.959z"
></path>
</svg>
</template>