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mirror of https://github.com/laurent22/joplin.git synced 2024-12-12 08:54:00 +02:00
joplin/packages/app-desktop/gui/note-viewer/index.html

664 lines
23 KiB
HTML

<!DOCTYPE html>
<html>
<head id="joplin-container-root-head">
<meta charset="UTF-8">
<style>
body {
overflow: hidden;
}
#joplin-container-content {
/* Needs this in case the content contains elements with absolute positioning */
/* Without this they would just stay at a fixed position when scrolling */
position: relative;
overflow-y: auto;
padding-left: 10px;
padding-right: 10px;
/* Note: the height is set via updateBodyHeight(). Setting it here to 100% */
/* won't work with some pages due to the position: relative */
}
#rendered-md {
/* This is used to enable the scroll-past end behaviour. The same height should */
/* be applied to the editor. */
padding-bottom: 400px;
}
.mark-selected {
background: #CF3F00;
color: white;
}
ul ul, ul ol, ol ul, ol ol {
margin-bottom: 0px;
}
</style>
</head>
<body id="joplin-container-body">
<div id="joplin-container-pluginAssetsContainer"></div>
<div id="joplin-container-markScriptContainer"></div>
<div id="joplin-container-content" ondragstart="return false;" ondrop="return false;"></div>
<script src="./lib.js"></script>
<script src="./scrollmap.js"></script>
<script>
// This is function used internally to send message from the webview to
// the host.
const ipcProxySendToHost = (methodName, arg) => {
window.postMessage({ target: 'main', name: methodName, args: [ arg ] }, '*');
}
const webviewApiPromises_ = {};
// This function is reserved for plugin, currently only to allow
// executing a command, but more features could be added to the object
// later on.
const webviewApi = {
postMessage: function(contentScriptId, message) {
const messageId = 'noteViewer_' + Date.now() + Math.random();
const promise = new Promise((resolve, reject) => {
webviewApiPromises_[messageId] = { resolve, reject };
});
ipcProxySendToHost('postMessageService.message', {
contentScriptId: contentScriptId,
viewId: '',
from: 'contentScript',
to: 'plugin',
id: messageId,
content: message,
});
return promise;
},
}
let pluginAssetsAdded_ = {};
try {
const contentElement = document.getElementById('joplin-container-content');
const ipc = {};
window.addEventListener('message', webviewLib.logEnabledEventHandler(event => {
// Here we only deal with messages that are sent from the main Electron process to the webview.
if (!event.data || event.data.target !== 'webview') return;
const callName = event.data.name;
const callData = event.data.data;
if (!ipc[callName]) {
console.warn('Missing IPC function:', event.data);
} else {
ipc[callName](callData);
}
}));
// Note: the scroll position source of truth is "percentScroll_". This is easier to manage than scrollTop because
// the scrollTop value depends on the images being loaded or not. For example, if the scrollTop is saved while
// images are being displayed then restored while images are being reloaded, the new scrollTop might be changed
// so that it is not greater than contentHeight. On the other hand, with percentScroll it is possible to restore
// it at any time knowing that it's not going to be changed because the content height has changed.
let percentScroll_ = 0;
let ignoreNextScrollTime_ = Date.now();
let ignoreNextScrollEventCount_ = 0;
// ignoreNextScrollEvent() provides a way to skip scroll events for a certain duration.
// In general, it should be called whenever the scroll value is set explicitely (programmatically)
// so as to differentiate scroll events generated by the user (when scrolling the view) and those
// generated by the application.
function ignoreNextScrollEvent() {
const now = Date.now();
if (now >= ignoreNextScrollTime_) ignoreNextScrollEventCount_ = 0;
if (ignoreNextScrollEventCount_ < 10) { // for safety
ignoreNextScrollTime_ = now + 200;
ignoreNextScrollEventCount_ += 1;
}
};
// Tests the next scroll event should be ignored and then decrements the count.
function isNextScrollEventIgnored() {
if (ignoreNextScrollEventCount_) {
if (Date.now() < ignoreNextScrollTime_) {
ignoreNextScrollEventCount_ -= 1;
return true;
}
ignoreNextScrollEventCount_ = 0;
}
return false;
}
function setPercentScroll(percent) {
// calculates viewer's GUI-dependent pixel-based raw percent
const viewerPercent = scrollmap.translateL2V(percent);
const newScrollTop = viewerPercent * maxScrollTop();
if (Math.floor(contentElement.scrollTop) !== Math.floor(newScrollTop)) {
ignoreNextScrollEvent();
percentScroll_ = percent;
contentElement.scrollTop = newScrollTop;
}
}
function restorePercentScroll() {
setPercentScroll(percentScroll_);
}
// Note that this function keeps track of what's been added so as not to add the same CSS files multiple times
// It also means that once an asset has been added it is never removed from the view, which in many case is
// desirable, but still something to keep in mind.
function addPluginAssets(assets) {
if (!assets) return;
const pluginAssetsContainer = document.getElementById('joplin-container-pluginAssetsContainer');
for (let i = 0; i < assets.length; i++) {
const asset = assets[i];
const assetId = asset.name ? asset.name : asset.path;
if (pluginAssetsAdded_[assetId]) continue;
pluginAssetsAdded_[assetId] = true;
if (asset.mime === 'application/javascript') {
const script = document.createElement('script');
script.src = asset.path;
pluginAssetsContainer.appendChild(script);
} else if (asset.mime === 'text/css') {
const link = document.createElement('link');
link.rel = 'stylesheet';
link.href = asset.path;
pluginAssetsContainer.appendChild(link);
}
}
}
ipc.scrollToHash = (event) => {
let retry = 0;
const fn = () => {
if (window.scrollToHashTimeoutID_) {
clearInterval(window.scrollToHashTimeoutID_);
window.scrollToHashTimeoutID_ = null;
}
if (document.readyState === 'complete' ||
// If scrollmap is present, Element.scrollIntoView() is also
// available when document.readyState is interactive.
document.readyState === 'interactive' && scrollmap.isPresent()) {
const hash = event.hash.toLowerCase();
const e = document.getElementById(hash);
if (e) {
e.scrollIntoView();
// It causes a scroll event, whose listener sent a new scroll
// position to Editor.
} else {
console.warn('Cannot find hash', hash);
}
} else {
retry += 1;
if (retry <= 10) {
window.scrollToHashTimeoutID_ = setTimeout(fn, 100);
}
}
};
fn();
}
function isVisible() {
// See the logic of hiding viewer in CoderMirror.tsx
return window.innerWidth > 1;
}
// https://stackoverflow.com/a/1977898/561309
function isImageReady(img) {
if (!img.complete) return false;
if (!img.naturalWidth || !img.naturalHeight) return false;
return true;
}
function allImagesLoaded() {
if (!isVisible()) return true; // In the case, images would not be loaded.
for (const image of document.images) {
if (!isImageReady(image)) return false;
}
return true;
}
let alreadyAllImagesLoaded = false;
// During a note is being rendered, its height is varying. To keep scroll
// consistency, observing the height of the content element and updating its
// scroll position is required. For the purpose, 'ResizeObserver' is used.
// ResizeObserver is standard and an element's counterpart to 'window.resize'
// event. It's overhead is cheaper than observation using an interval timer.
//
// To observe the scroll height of the content element, adding, removing and
// resizing of its children should be observed. So, the combination of
// ResizeObserver (used for resizing) and MutationObserver (used for ading
// and removing) is used.
//
// References:
// https://developer.mozilla.org/en-US/docs/Web/API/ResizeObserver
// https://developer.mozilla.org/en-US/docs/Web/API/MutationObserver
//
// By using them, this observeRendering() function provides a efficient way
// to observe the changes of the scroll height of the content element
// using a callback approach.
function observeRendering(callback, compress = false) {
let lastScrollHeight = 0;
let lastClientHeight = 0;
const fn = (cause) => {
const sh = contentElement.scrollHeight;
const ch = contentElement.clientHeight;
const heightChanged = (sh !== lastScrollHeight || ch !== lastClientHeight);
if (!compress || heightChanged) {
lastScrollHeight = sh;
lastClientHeight = ch;
callback(cause, sh, heightChanged);
}
};
// 'resized' means DOM Layout change or Window resize event
let resizeObserver = new ResizeObserver(() => fn('resized'));
// An HTML document to be rendered is added and removed as a child of
// the content element for each setHtml() invocation.
let mutationObserver = new MutationObserver(entries => {
const e = entries[0];
e.removedNodes.forEach(n => n instanceof Element && resizeObserver.unobserve(n));
e.addedNodes.forEach(n => n instanceof Element && resizeObserver.observe(n));
if (e.removedNodes.length + e.addedNodes.length) fn('dom-changed');
});
mutationObserver.observe(contentElement, { childList: true });
return { mutationObserver, resizeObserver };
};
// To suppress too frequent restoring of scroll positions and refreshing of the scroll map
let restoreAndRefreshTimeoutID_ = null;
let restoreAndRefreshTimeout_ = Date.now();
// A callback anonymous function invoked when the scroll height changes.
const onRendering = observeRendering((cause, height, heightChanged) => {
if (!alreadyAllImagesLoaded && !scrollmap.isPresent()) {
const loaded = allImagesLoaded();
if (loaded) {
alreadyAllImagesLoaded = true;
scrollmap.refresh();
restorePercentScroll();
ipcProxySendToHost('noteRenderComplete');
return;
}
}
if (!heightChanged) return;
const restoreAndRefresh = () => {
scrollmap.refresh();
restorePercentScroll();
};
const now = Date.now();
if (now < restoreAndRefreshTimeout_) {
if (restoreAndRefreshTimeoutID_) {
clearTimeout(restoreAndRefreshTimeoutID_);
restoreAndRefreshTimeoutID_ = null;
}
const msec = Math.min(1000, restoreAndRefreshTimeout_ - now);
restoreAndRefreshTimeoutID_ = setTimeout(restoreAndRefresh, msec);
} else {
restoreAndRefresh();
}
restoreAndRefreshTimeout_ = now + 200;
});
ipc.focus = (event) => {
const dummyID = 'joplin-content-focus-dummy';
if (! document.getElementById(dummyID)) {
const focusDummy = '<div style="width: 0; height: 0; overflow: hidden"><a id="' + dummyID + '" href="#">focus dummy</a></div>';
contentElement.insertAdjacentHTML("afterbegin", focusDummy);
}
const scrollTop = contentElement.scrollTop;
document.getElementById(dummyID).focus();
contentElement.scrollTop = scrollTop;
}
ipc.setHtml = (event) => {
const html = event.html;
markJsHackMarkerInserted_ = false;
updateBodyHeight();
alreadyAllImagesLoaded = false;
contentElement.innerHTML = html;
scrollmap.create(event.options.markupLineCount);
restorePercentScroll(); // First, a quick treatment is applied.
addPluginAssets(event.options.pluginAssets);
if (event.options.downloadResources === 'manual') {
webviewLib.setupResourceManualDownload();
}
document.dispatchEvent(new Event('joplin-noteDidUpdate'));
if (scrollmap.isPresent()) {
// Now, ready to receive scrollToHash/setPercentScroll from Editor.
ipcProxySendToHost('noteRenderComplete');
}
}
ipc.setPercentScroll = (event) => {
setPercentScroll(event.percent);
}
// HACK for Mark.js bug - https://github.com/julmot/mark.js/issues/127
let markJsHackMarkerInserted_ = false;
function addMarkJsSpaceHack(document) {
if (markJsHackMarkerInserted_) return;
const prepareElementsForMarkJs = (elements, type) => {
// const markJsHackMarker_ = '&#8203; &#8203;'
const markJsHackMarker_ = ' ';
for (let i = 0; i < elements.length; i++) {
if (!type) {
elements[i].insertAdjacentHTML('beforeend', markJsHackMarker_);
} else if (type === 'insertBefore') {
elements[i].insertAdjacentHTML('beforeBegin', markJsHackMarker_);
}
}
}
prepareElementsForMarkJs(contentElement.getElementsByTagName('p'));
prepareElementsForMarkJs(contentElement.getElementsByTagName('div'));
prepareElementsForMarkJs(contentElement.getElementsByTagName('br'), 'insertBefore');
markJsHackMarkerInserted_ = true;
}
let mark_ = null;
let markSelectedElement_ = null;
function setMarkers(keywords, options = null) {
if (!options) options = {};
// TODO: Add support for scriptType on mobile and CLI
if (!mark_) {
mark_ = new Mark(document.getElementById('joplin-container-content'), {
exclude: ['img'],
acrossElements: true,
});
}
addMarkJsSpaceHack(document);
mark_.unmark()
if (markSelectedElement_) markSelectedElement_.classList.remove('mark-selected');
let selectedElement = null;
let elementIndex = 0;
const markKeywordOptions = {};
if ('separateWordSearch' in options) markKeywordOptions.separateWordSearch = options.separateWordSearch;
for (let i = 0; i < keywords.length; i++) {
let keyword = keywords[i];
markJsUtils.markKeyword(mark_, keyword, {
pregQuote: pregQuote,
replaceRegexDiacritics: replaceRegexDiacritics,
}, markKeywordOptions);
}
}
let markLoader_ = { state: 'idle', whenDone: null };
ipc.setMarkers = (event) => {
const keywords = event.keywords;
const options = event.options;
if (!keywords.length && markLoader_.state === 'idle') return;
if (markLoader_.state === 'idle') {
markLoader_ = {
state: 'loading',
whenDone: {keywords:keywords, options:options},
};
const script = document.createElement('script');
script.onload = function() {
markLoader_.state = 'ready';
setMarkers(markLoader_.whenDone.keywords, markLoader_.whenDone.options);
};
script.src = '../../vendor/lib/mark.js/dist/mark.min.js';
document.getElementById('joplin-container-markScriptContainer').appendChild(script);
} else if (markLoader_.state === 'ready') {
setMarkers(keywords, options);
} else if (markLoader_.state === 'loading') {
markLoader_.whenDone = {keywords:keywords, options:options};
}
}
function maxScrollTop() {
return Math.max(0, contentElement.scrollHeight - contentElement.clientHeight);
}
function maxScrollLeft() {
return Math.max(0, contentElement.scrollWidth - contentElement.clientWidth);
}
// The body element needs to have a fixed height for the content to be scrollable
function updateBodyHeight() {
document.getElementById('joplin-container-body').style.height = window.innerHeight + 'px';
document.getElementById('joplin-container-content').style.height = window.innerHeight + 'px';
}
function getPercentFromViewer() {
const m = maxScrollTop();
// As of 2021, if zoomFactor != 1, underlying Chrome returns scrollTop with
// some numerical error. It can be more than maxScrollTop().
const viewerPecent = m ? Math.min(1, contentElement.scrollTop / m) : 0;
// calculates GUI-independent line-based logical percent
const percent = scrollmap.translateV2L(viewerPecent);
return percent;
}
// If zoom factor is not 1, Electron/Chromium calculates scrollTop incorrectly.
// This is automatically set.
let zoomFactorIsNotOne = false;
// When custom smooth scrolling is ongoing, remainedScrollDx/Dy keep the remaining
// amount of scrolling.
let remainedScrollDx = 0, remainedScrollDy = 0, remainedScrollTimerId = null;
function resetSmoothScroll() { remainedScrollDx = 0; remainedScrollDy = 0; }
// To avoid Electron/Chromium's scrolling bug when zoom fator is not 1,
// Custom scrolling is implemented. This is used only when zoom factor is not 1.
// If smoothly argument is true, smooth scrolling is performed.
// See https://github.com/laurent22/joplin/pull/5606#issuecomment-964293459
function customScroll(wheelEvent, smoothly) {
const linePixels = 100 / 3;
const pagePixelsX = Math.max(linePixels, contentElement.clientWidth);
const pagePixelsY = Math.max(linePixels, contentElement.clientHeight);
let pixelsPerUnitX = 1, pixelsPerUnitY = 1; // for WheelEvent.DOM_DELTA_PIXEL
if (wheelEvent.deltaMode === WheelEvent.DOM_DELTA_LINE) {
pixelsPerUnitX = pixelsPerUnitY = linePixels;
} else if (wheelEvent.deltaMode === WheelEvent.DOM_DELTA_PAGE) {
pixelsPerUnitX = pagePixelsX;
pixelsPerUnitY = pagePixelsY;
}
if (!smoothly) {
if (wheelEvent.deltaX) {
const dx = wheelEvent.deltaX * pixelsPerUnitX;
contentElement.scrollLeft = Math.max(0, Math.min(maxScrollLeft(), contentElement.scrollLeft + dx));
}
if (wheelEvent.deltaY) {
const dy = wheelEvent.deltaY * pixelsPerUnitY;
contentElement.scrollTop = Math.max(0, Math.min(maxScrollTop(), contentElement.scrollTop + dy));
}
} else {
if (Math.sign(remainedScrollDx) !== Math.sign(wheelEvent.deltaX)) remainedScrollDx = 0;
if (Math.sign(remainedScrollDy) !== Math.sign(wheelEvent.deltaY)) remainedScrollDy = 0;
remainedScrollDx += wheelEvent.deltaX * pixelsPerUnitX;
remainedScrollDy += wheelEvent.deltaY * pixelsPerUnitY;
const maxDx = Math.max(8.5, Math.min(pagePixelsX, Math.abs(remainedScrollDx)) / 5);
const maxDy = Math.max(8.5, Math.min(pagePixelsY, Math.abs(remainedScrollDy)) / 5);
const f = () => {
if (remainedScrollTimerId) {
clearTimeout(remainedScrollTimerId);
remainedScrollTimerId = null;
}
if (remainedScrollDx) {
const dx = Math.max(-maxDx, Math.min(maxDx, remainedScrollDx));
remainedScrollDx -= dx;
contentElement.scrollLeft = Math.max(0, Math.min(maxScrollLeft(), contentElement.scrollLeft + dx));
}
if (remainedScrollDy) {
const dy = Math.max(-maxDy, Math.min(maxDy, remainedScrollDy));
remainedScrollDy -= dy;
contentElement.scrollTop = Math.max(0, Math.min(maxScrollTop(), contentElement.scrollTop + dy));
}
if (remainedScrollDx || remainedScrollDy) remainedScrollTimerId = setTimeout(f, 20);
};
f();
}
}
contentElement.addEventListener('wheel', webviewLib.logEnabledEventHandler(e => {
// When zoomFactor is not 1 (using an HD display is a typical case),
// DOM element's scrollTop is incorrectly calculated after wheel scroll events
// in the layer of Electron/Chromium, as of 2021-09-23.
// To avoid this problem, prevent the upstream from calculating scrollTop and
// calculate by yourself by accumulating wheel events.
// https://github.com/laurent22/joplin/pull/5496
// When the Electron/Chromium bug is fixed, remove this listener.
// If scrollTop ever has a fraction part, zoomFactor is not 1.
if (zoomFactorIsNotOne || !Number.isInteger(contentElement.scrollTop)) {
zoomFactorIsNotOne = true;
customScroll(e, true);
e.preventDefault();
}
}));
contentElement.addEventListener('scroll', webviewLib.logEnabledEventHandler(e => {
lastScrollTop_ = contentElement.scrollTop;
// If the last scroll event was done by the application, ignoreNextScrollEvent() is called and
// we can use that to skip the event handling. We skip it because in that case
// the scroll position has already been updated. Also we add a 200ms interval
// because otherwise it's most likely a glitch where we called ipc.setPercentScroll
// but the scroll event listener has not been called.
if (isNextScrollEventIgnored()) return;
percentScroll_ = getPercentFromViewer();
ipcProxySendToHost('percentScroll', percentScroll_);
}));
ipc['postMessageService.response'] = function(event) {
const promise = webviewApiPromises_[event.responseId];
if (!promise) {
console.warn('postMessageService.response: could not find callback for message', event);
return;
}
if (event.error) {
promise.reject(event.error);
} else {
promise.resolve(event.response);
}
}
window.addEventListener('hashchange', webviewLib.logEnabledEventHandler(e => {
if (!window.location.hash) return;
// The timeout is necessary to prevent a race condition and give time for the window to scroll
setTimeout(() => {
// Reset the window hash to allow clicking on the same anchor link more than once
window.location.hash = '';
}, 100);
}));
document.addEventListener('contextmenu', webviewLib.logEnabledEventHandler(event => {
let element = event.target;
// To handle right clicks on resource icons
if (element && !element.getAttribute('data-resource-id')) element = element.parentElement;
if (element && element.getAttribute('data-resource-id')) {
ipcProxySendToHost('contextMenu', {
type: element.getAttribute('src') ? 'image' : 'resource',
resourceId: element.getAttribute('data-resource-id'),
});
} else {
const selectedText = window.getSelection().toString();
if (selectedText) {
const linkToCopy = event.target && event.target.getAttribute('href') ? event.target.getAttribute('href') : null;
ipcProxySendToHost('contextMenu', {
type: 'text',
textToCopy: selectedText,
linkToCopy: linkToCopy,
});
} else if (event.target.getAttribute('href')) {
ipcProxySendToHost('contextMenu', {
type: 'link',
textToCopy: event.target.getAttribute('href'),
});
}
}
}));
webviewLib.initialize({
postMessage: ipcProxySendToHost,
});
// Disable drag and drop otherwise it's possible to drop a URL
// on it and it will open in the view as a website.
document.addEventListener('drop', webviewLib.logEnabledEventHandler(e => {
e.preventDefault();
e.stopPropagation();
}));
document.addEventListener('dragover', webviewLib.logEnabledEventHandler(e => {
e.preventDefault();
e.stopPropagation();
}));
document.addEventListener('dragover', webviewLib.logEnabledEventHandler(e => {
e.preventDefault();
}));
let lastClientWidth_ = NaN, lastClientHeight_ = NaN, lastScrollTop_ = NaN;
window.addEventListener('resize', webviewLib.logEnabledEventHandler(() => {
updateBodyHeight();
// When zoomFactor is changed, resize event happens.
zoomFactorIsNotOne = false;
resetSmoothScroll();
// If this event resizes contentElement, ignore the scroll event caused by it.
const cw = contentElement.clientWidth;
const ch = contentElement.clientHeight;
const top = contentElement.scrollTop;
if (!(cw === lastClientWidth_ && ch === lastClientHeight_)) {
// Since scroll listeners are invoked before ResizeObserver and
// resize listeners are invoked before scroll listeners,
// this code should be here to ignore scroll events.
if (top !== lastScrollTop_) ignoreNextScrollEvent();
lastClientWidth_ = cw; lastClientHeight_ = ch; lastScrollTop_ = top;
}
}));
// Prevent middle-click as that would open the URL in an Electron window
// https://github.com/laurent22/joplin/issues/3287
window.addEventListener('auxclick', webviewLib.logEnabledEventHandler((event) => {
event.preventDefault();
}));
updateBodyHeight();
} catch (error) {
ipcProxySendToHost('error:' + JSON.stringify(webviewLib.cloneError(error)));
throw error;
}
</script>
</body>
</html>