HackMD/public/js/syncscroll.js
2016-03-15 10:56:53 +08:00

301 lines
9.9 KiB
JavaScript

// Inject line numbers for sync scroll.
function addPart(tokens, idx) {
if (tokens[idx].map && tokens[idx].level === 0) {
var startline = tokens[idx].map[0] + 1;
var endline = tokens[idx].map[1];
tokens[idx].attrJoin('class', 'part');
tokens[idx].attrJoin('data-startline', startline);
tokens[idx].attrJoin('data-endline', endline);
}
}
md.renderer.rules.blockquote_open = function (tokens, idx, options, env, self) {
tokens[idx].attrJoin('class', 'raw');
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.table_open = function (tokens, idx, options, env, self) {
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.bullet_list_open = function (tokens, idx, options, env, self) {
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.list_item_open = function (tokens, idx, options, env, self) {
tokens[idx].attrJoin('class', 'raw');
if (tokens[idx].map) {
var startline = tokens[idx].map[0] + 1;
var endline = tokens[idx].map[1];
tokens[idx].attrJoin('class', 'part');
tokens[idx].attrJoin('data-startline', startline);
tokens[idx].attrJoin('data-endline', endline);
}
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.ordered_list_open = function (tokens, idx, options, env, self) {
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.link_open = function (tokens, idx, options, env, self) {
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.paragraph_open = function (tokens, idx, options, env, self) {
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.heading_open = function (tokens, idx, options, env, self) {
tokens[idx].attrJoin('class', 'raw');
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
};
md.renderer.rules.fence = function (tokens, idx, options, env, self) {
var token = tokens[idx],
info = token.info ? md.utils.unescapeAll(token.info).trim() : '',
langName = '',
highlighted;
if (info) {
langName = info.split(/\s+/g)[0];
token.attrJoin('class', options.langPrefix + langName.replace(/\=$|\=\d+$|\=\+$/, ''));
token.attrJoin('class', 'hljs');
}
if (options.highlight) {
highlighted = options.highlight(token.content, langName) || md.utils.escapeHtml(token.content);
} else {
highlighted = md.utils.escapeHtml(token.content);
}
if (highlighted.indexOf('<pre') === 0) {
return highlighted + '\n';
}
if (tokens[idx].map && tokens[idx].level === 0) {
var startline = tokens[idx].map[0] + 1;
var endline = tokens[idx].map[1];
return '<pre class="part" data-startline="' + startline + '" data-endline="' + endline + '"><code' + self.renderAttrs(token) + '>'
+ highlighted
+ '</code></pre>\n';
}
return '<pre><code' + self.renderAttrs(token) + '>'
+ highlighted
+ '</code></pre>\n';
};
md.renderer.rules.code_block = function (tokens, idx, options, env, self) {
if (tokens[idx].map && tokens[idx].level === 0) {
var startline = tokens[idx].map[0] + 1;
var endline = tokens[idx].map[1];
return '<pre class="part" data-startline="' + startline + '" data-endline="' + endline + '"><code>' + md.utils.escapeHtml(tokens[idx].content) + '</code></pre>\n';
}
return '<pre><code>' + md.utils.escapeHtml(tokens[idx].content) + '</code></pre>\n';
};
function renderContainer(tokens, idx, options, env, self) {
tokens[idx].attrJoin('role', 'alert');
tokens[idx].attrJoin('class', 'alert');
tokens[idx].attrJoin('class', 'alert-' + tokens[idx].info.trim());
addPart(tokens, idx);
return self.renderToken.apply(self, arguments);
}
md.use(window.markdownitContainer, 'success', { render: renderContainer });
md.use(window.markdownitContainer, 'info', { render: renderContainer });
md.use(window.markdownitContainer, 'warning', { render: renderContainer });
md.use(window.markdownitContainer, 'danger', { render: renderContainer });
var preventSyncScroll = false;
//var editorScrollThrottle = 100;
var buildMapThrottle = 100;
var viewScrolling = false;
var viewScrollingDelay = 200;
var viewScrollingTimer = null;
//editor.on('scroll', _.throttle(syncScrollToView, editorScrollThrottle));
editor.on('scroll', syncScrollToView);
ui.area.view.on('scroll', function () {
viewScrolling = true;
clearTimeout(viewScrollingTimer);
viewScrollingTimer = setTimeout(function () {
viewScrolling = false;
}, viewScrollingDelay);
});
//editor.on('scroll', _.debounce(syncScrollToView, syncScrollDelay));
//ui.area.view.on('scroll', _.debounce(syncScrollToEdit, 50));
var scrollMap, lineHeightMap, viewTop, viewBottom;
viewAjaxCallback = clearMap;
function clearMap() {
scrollMap = null;
lineHeightMap = null;
viewTop = null;
viewBottom = null;
}
var buildMap = _.throttle(buildMapInner, buildMapThrottle);
// Build offsets for each line (lines can be wrapped)
// That's a bit dirty to process each line everytime, but ok for demo.
// Optimizations are required only for big texts.
function buildMapInner(syncBack) {
var i, offset, nonEmptyList, pos, a, b, _lineHeightMap, linesCount,
acc, _scrollMap;
offset = ui.area.view.scrollTop() - ui.area.view.offset().top;
_scrollMap = [];
nonEmptyList = [];
_lineHeightMap = [];
viewTop = 0;
viewBottom = ui.area.view[0].scrollHeight - ui.area.view.height();
acc = 0;
var lines = editor.getValue().split('\n');
var lineHeight = editor.defaultTextHeight();
for (i = 0; i < lines.length; i++) {
var str = lines[i];
_lineHeightMap.push(acc);
if (str.length === 0) {
acc++;
continue;
}
var h = editor.heightAtLine(i + 1) - editor.heightAtLine(i);
acc += Math.round(h / lineHeight);
}
_lineHeightMap.push(acc);
linesCount = acc;
for (i = 0; i < linesCount; i++) {
_scrollMap.push(-1);
}
nonEmptyList.push(0);
// make the first line go top
_scrollMap[0] = viewTop;
var parts = ui.area.markdown.find('.part').toArray();
for (i = 0; i < parts.length; i++) {
var $el = $(parts[i]),
t = $el.attr('data-startline') - 1;
if (t === '') {
return;
}
t = _lineHeightMap[t];
if (t !== 0 && t !== nonEmptyList[nonEmptyList.length - 1]) {
nonEmptyList.push(t);
}
_scrollMap[t] = Math.round($el.offset().top + offset - 10);
}
nonEmptyList.push(linesCount);
_scrollMap[linesCount] = ui.area.view[0].scrollHeight;
pos = 0;
for (i = 1; i < linesCount; i++) {
if (_scrollMap[i] !== -1) {
pos++;
continue;
}
a = nonEmptyList[pos];
b = nonEmptyList[pos + 1];
_scrollMap[i] = Math.round((_scrollMap[b] * (i - a) + _scrollMap[a] * (b - i)) / (b - a));
}
_scrollMap[0] = 0;
scrollMap = _scrollMap;
lineHeightMap = _lineHeightMap;
if (loaded && syncBack)
syncScrollToView();
}
function getPartByEditorLineNo(lineNo) {
var part = null;
ui.area.markdown.find('.part').each(function (n, el) {
if (part) return;
var $el = $(el),
t = $el.data('startline') - 1,
f = $el.data('endline') - 1;
if (t === '' || f === '') {
return;
}
if (lineNo >= t && lineNo <= f) {
part = $el;
}
});
if (part)
return {
startline: part.data('startline') - 1,
endline: part.data('endline') - 1,
linediff: Math.abs(part.data('endline') - part.data('startline')) + 1,
element: part
};
else
return null;
}
function getEditorLineNoByTop(top) {
for (var i = 0; i < lineHeightMap.length; i++)
if (lineHeightMap[i] * editor.defaultTextHeight() > top)
return i;
return null;
}
function syncScrollToView(event, _lineNo) {
if (currentMode != modeType.both) return;
if (preventSyncScroll) {
preventSyncScroll = false;
return;
}
var lineNo, posTo;
var scrollInfo = editor.getScrollInfo();
if (!scrollMap || !lineHeightMap) {
buildMap(true);
return;
}
if (!_lineNo) {
var topDiffPercent, posToNextDiff;
var textHeight = editor.defaultTextHeight();
lineNo = Math.floor(scrollInfo.top / textHeight);
// if reach the last line, will start lerp to the bottom
var diffToBottom = (scrollInfo.top + scrollInfo.clientHeight) - (scrollInfo.height - textHeight);
if (scrollInfo.height > scrollInfo.clientHeight && diffToBottom > 0) {
topDiffPercent = diffToBottom / textHeight;
posTo = scrollMap[lineNo + 1];
posToNextDiff = (viewBottom - posTo) * topDiffPercent;
posTo += Math.floor(posToNextDiff);
} else {
topDiffPercent = (scrollInfo.top % textHeight) / textHeight;
posTo = scrollMap[lineNo];
posToNextDiff = (scrollMap[lineNo + 1] - posTo) * topDiffPercent;
posTo += Math.floor(posToNextDiff);
}
} else {
if (viewScrolling) return;
posTo = scrollMap[lineHeightMap[_lineNo]];
}
var posDiff = Math.abs(ui.area.view.scrollTop() - posTo);
var duration = posDiff / 50;
ui.area.view.stop(true, true).animate({
scrollTop: posTo
}, duration >= 100 ? duration : 100, "linear");
/*
if (posDiff > scrollInfo.clientHeight / 5) {
var duration = posDiff / 50;
ui.area.view.stop(true, true).animate({
scrollTop: posTo
}, duration >= 100 ? duration : 100, "linear");
} else {
ui.area.view.stop(true, true).scrollTop(posTo);
}
*/
}