/* Functionality for finding, storing, and restoring selections
*
* This does not provide a generic API, just the minimal functionality
* required by the CodeMirror system.
*/
// Namespace object.
var select = {};
(function () {
select.ie_selection = document.selection && document.selection.createRangeCollection;
// Find the 'top-level' (defined as 'a direct child of the node
// passed as the top argument') node that the given node is
// contained in. Return null if the given node is not inside the top
// node.
function topLevelNodeAt(node, top) {
while (node && node.parentNode != top)
node = node.parentNode;
return node;
}
// Find the top-level node that contains the node before this one.
function topLevelNodeBefore(node, top) {
while (!node.previousSibling && node.parentNode != top)
node = node.parentNode;
return topLevelNodeAt(node.previousSibling, top);
}
var fourSpaces = "\u00a0\u00a0\u00a0\u00a0";
select.scrollToNode = function (element) {
if (!element) return;
var doc = element.ownerDocument, body = doc.body,
win = (doc.defaultView || doc.parentWindow),
html = doc.documentElement,
atEnd = !element.nextSibling || !element.nextSibling.nextSibling
|| !element.nextSibling.nextSibling.nextSibling;
// In Opera (and recent Webkit versions), BR elements *always*
// have a offsetTop property of zero.
var compensateHack = 0;
while (element && !element.offsetTop) {
compensateHack++;
element = element.previousSibling;
}
// atEnd is another kludge for these browsers -- if the cursor is
// at the end of the document, and the node doesn't have an
// offset, just scroll to the end.
if (compensateHack == 0) atEnd = false;
var y = compensateHack * (element ? element.offsetHeight : 0), x = 0, pos = element;
while (pos && pos.offsetParent) {
y += pos.offsetTop;
// Don't count X offset for <br> nodes
if (!isBR(pos))
x += pos.offsetLeft;
pos = pos.offsetParent;
}
var scroll_x = body.scrollLeft || html.scrollLeft || 0,
scroll_y = body.scrollTop || html.scrollTop || 0,
screen_x = x - scroll_x, screen_y = y - scroll_y, scroll = false;
if (screen_x < 0 || screen_x > (win.innerWidth || html.clientWidth || 0)) {
scroll_x = x;
scroll = true;
}
if (screen_y < 0 || atEnd || screen_y > (win.innerHeight || html.clientHeight || 0) - 50) {
scroll_y = atEnd ? 1e6 : y;
scroll = true;
}
if (scroll) win.scrollTo(scroll_x, scroll_y);
};
select.scrollToCursor = function (container) {
select.scrollToNode(select.selectionTopNode(container, true) || container.firstChild);
};
// Used to prevent restoring a selection when we do not need to.
var currentSelection = null;
select.snapshotChanged = function () {
if (currentSelection) currentSelection.changed = true;
};
// This is called by the code in editor.js whenever it is replacing
// a text node. The function sees whether the given oldNode is part
// of the current selection, and updates this selection if it is.
// Because nodes are often only partially replaced, the length of
// the part that gets replaced has to be taken into account -- the
// selection might stay in the oldNode if the newNode is smaller
// than the selection's offset. The offset argument is needed in
// case the selection does move to the new object, and the given
// length is not the whole length of the new node (part of it might
// have been used to replace another node).
select.snapshotReplaceNode = function (from, to, length, offset) {
if (!currentSelection) return;
function replace(point) {
if (from == point.node) {
currentSelection.changed = true;
if (length && point.offset > length) {
point.offset -= length;
}
else {
point.node = to;
point.offset += (offset || 0);
}
}
}
replace(currentSelection.start);
replace(currentSelection.end);
};
select.snapshotMove = function (from, to, distance, relative, ifAtStart) {
if (!currentSelection) return;
function move(point) {
if (from == point.node && (!ifAtStart || point.offset == 0)) {
currentSelection.changed = true;
point.node = to;
if (relative) point.offset = Math.max(0, point.offset + distance);
else point.offset = distance;
}
}
move(currentSelection.start);
move(currentSelection.end);
};
// Most functions are defined in two ways, one for the IE selection
// model, one for the W3C one.
if (select.ie_selection) {
function selectionNode(win, start) {
var range = win.document.selection.createRange();
range.collapse(start);
function nodeAfter(node) {
var found = null;
while (!found && node) {
found = node.nextSibling;
node = node.parentNode;
}
return nodeAtStartOf(found);
}
function nodeAtStartOf(node) {
while (node && node.firstChild) node = node.firstChild;
return {node: node, offset: 0};
}
var containing = range.parentElement();
if (!isAncestor(win.document.body, containing)) return null;
if (!containing.firstChild) return nodeAtStartOf(containing);
var working = range.duplicate();
working.moveToElementText(containing);
working.collapse(true);
for (var cur = containing.firstChild; cur; cur = cur.nextSibling) {
if (cur.nodeType == 3) {
var size = cur.nodeValue.length;
working.move("character", size);
}
else {
working.moveToElementText(cur);
working.collapse(false);
}
var dir = range.compareEndPoints("StartToStart", working);
if (dir == 0) return nodeAfter(cur);
if (dir == 1) continue;
if (cur.nodeType != 3) return nodeAtStartOf(cur);
working.setEndPoint("StartToEnd", range);
return {node: cur, offset: size - working.text.length};
}
return nodeAfter(containing);
}
select.markSelection = function (win) {
currentSelection = null;
var sel = win.document.selection;
if (!sel) return;
var start = selectionNode(win, true),
end = selectionNode(win, false);
if (!start || !end) return;
currentSelection = {start: start, end: end, window: win, changed: false};
};
select.selectMarked = function () {
if (!currentSelection || !currentSelection.changed) return;
var win = currentSelection.window, doc = win.document;
function makeRange(point) {
var range = doc.body.createTextRange(),
node = point.node;
if (!node) {
range.moveToElementText(currentSelection.window.document.body);
range.collapse(false);
}
else if (node.nodeType == 3) {
range.moveToElementText(node.parentNode);
var offset = point.offset;
while (node.previousSibling) {
node = node.previousSibling;
offset += (node.innerText || "").length;
}
range.move("character", offset);
}
else {
range.moveToElementText(node);
range.collapse(true);
}
return range;
}
var start = makeRange(currentSelection.start), end = makeRange(currentSelection.end);
start.setEndPoint("StartToEnd", end);
start.select();
};
// Get the top-level node that one end of the cursor is inside or
// after. Note that this returns false for 'no cursor', and null
// for 'start of document'.
select.selectionTopNode = function (container, start) {
var selection = container.ownerDocument.selection;
if (!selection) return false;
var range = selection.createRange(), range2 = range.duplicate();
range.collapse(start);
var around = range.parentElement();
if (around && isAncestor(container, around)) {
// Only use this node if the selection is not at its start.
range2.moveToElementText(around);
if (range.compareEndPoints("StartToStart", range2) == 1)
return topLevelNodeAt(around, container);
}
// Move the start of a range to the start of a node,
// compensating for the fact that you can't call
// moveToElementText with text nodes.
function moveToNodeStart(range, node) {
if (node.nodeType == 3) {
var count = 0, cur = node.previousSibling;
while (cur && cur.nodeType == 3) {
count += cur.nodeValue.length;
cur = cur.previousSibling;
}
if (cur) {
try {
range.moveToElementText(cur);
}
catch (e) {
return false;
}
range.collapse(false);
}
else range.moveToElementText(node.parentNode);
if (count) range.move("character", count);
}
else {
try {
range.moveToElementText(node);
}
catch (e) {
return false;
}
}
return true;
}
// Do a binary search through the container object, comparing
// the start of each node to the selection
var start = 0, end = container.childNodes.length - 1;
while (start < end) {
var middle = Math.ceil((end + start) / 2), node = container.childNodes[middle];
if (!node) return false; // Don't ask. IE6 manages this sometimes.
if (!moveToNodeStart(range2, node)) return false;
if (range.compareEndPoints("StartToStart", range2) == 1)
start = middle;
else
end = middle - 1;
}
return container.childNodes[start] || null;
};
// Place the cursor after this.start. This is only useful when
// manually moving the cursor instead of restoring it to its old
// position.
select.focusAfterNode = function (node, container) {
var range = container.ownerDocument.body.createTextRange();
range.moveToElementText(node || container);
range.collapse(!node);
range.select();
};
select.somethingSelected = function (win) {
var sel = win.document.selection;
return sel && (sel.createRange().text != "");
};
function insertAtCursor(window, html) {
var selection = window.document.selection;
if (selection) {
var range = selection.createRange();
range.pasteHTML(html);
range.collapse(false);
range.select();
}
}
// Used to normalize the effect of the enter key, since browsers
// do widely different things when pressing enter in designMode.
select.insertNewlineAtCursor = function (window) {
insertAtCursor(window, "<br>");
};
select.insertTabAtCursor = function (window) {
insertAtCursor(window, fourSpaces);
};
// Get the BR node at the start of the line on which the cursor
// currently is, and the offset into the line. Returns null as
// node if cursor is on first line.
select.cursorPos = function (container, start) {
var selection = container.ownerDocument.selection;
if (!selection) return null;
var topNode = select.selectionTopNode(container, start);
while (topNode && !isBR(topNode))
topNode = topNode.previousSibling;
var range = selection.createRange(), range2 = range.duplicate();
range.collapse(start);
if (topNode) {
range2.moveToElementText(topNode);
range2.collapse(false);
}
else {
// When nothing is selected, we can get all kinds of funky errors here.
try {
range2.moveToElementText(container);
}
catch (e) {
return null;
}
range2.collapse(true);
}
range.setEndPoint("StartToStart", range2);
return {node: topNode, offset: range.text.length};
};
select.setCursorPos = function (container, from, to) {
function rangeAt(pos) {
var range = container.ownerDocument.body.createTextRange();
if (!pos.node) {
range.moveToElementText(container);
range.collapse(true);
}
else {
range.moveToElementText(pos.node);
range.collapse(false);
}
range.move("character", pos.offset);
return range;
}
var range = rangeAt(from);
if (to && to != from)
range.setEndPoint("EndToEnd", rangeAt(to));
range.select();
}
// Some hacks for storing and re-storing the selection when the editor loses and regains focus.
select.getBookmark = function (container) {
var from = select.cursorPos(container, true), to = select.cursorPos(container, false);
if (from && to) return {from: from, to: to};
};
// Restore a stored selection.
select.setBookmark = function (container, mark) {
if (!mark) return;
select.setCursorPos(container, mark.from, mark.to);
};
}
// W3C model
else {
// Store start and end nodes, and offsets within these, and refer
// back to the selection object from those nodes, so that this
// object can be updated when the nodes are replaced before the
// selection is restored.
select.markSelection = function (win) {
var selection = win.getSelection();
if (!selection || selection.rangeCount == 0)
return (currentSelection = null);
var range = selection.getRangeAt(0);
currentSelection = {
start: {node: range.startContainer, offset: range.startOffset},
end: {node: range.endContainer, offset: range.endOffset},
window: win,
changed: false
};
// We want the nodes right at the cursor, not one of their
// ancestors with a suitable offset. This goes down the DOM tree
// until a 'leaf' is reached (or is it *up* the DOM tree?).
function normalize(point) {
while (point.node.nodeType != 3 && !isBR(point.node)) {
var newNode = point.node.childNodes[point.offset] || point.node.nextSibling;
point.offset = 0;
while (!newNode && point.node.parentNode) {
point.node = point.node.parentNode;
newNode = point.node.nextSibling;
}
point.node = newNode;
if (!newNode)
break;
}
}
normalize(currentSelection.start);
normalize(currentSelection.end);
};
select.selectMarked = function () {
var cs = currentSelection;
// on webkit-based browsers, it is apparently possible that the
// selection gets reset even when a node that is not one of the
// endpoints get messed with. the most common situation where
// this occurs is when a selection is deleted or overwitten. we
// check for that here.
function focusIssue() {
return cs.start.node == cs.end.node && cs.start.offset == 0 && cs.end.offset == 0;
}
if (!cs || !(cs.changed || (webkit && focusIssue()))) return;
var win = cs.window, range = win.document.createRange();
function setPoint(point, which) {
if (point.node) {
// Some magic to generalize the setting of the start and end
// of a range.
if (point.offset == 0)
range["set" + which + "Before"](point.node);
else
range["set" + which](point.node, point.offset);
}
else {
range.setStartAfter(win.document.body.lastChild || win.document.body);
}
}
setPoint(cs.end, "End");
setPoint(cs.start, "Start");
selectRange(range, win);
};
// Helper for selecting a range object.
function selectRange(range, window) {
var selection = window.getSelection();
selection.removeAllRanges();
selection.addRange(range);
};
function selectionRange(window) {
var selection = window.getSelection();
if (!selection || selection.rangeCount == 0)
return false;
else
return selection.getRangeAt(0);
}
// Finding the top-level node at the cursor in the W3C is, as you
// can see, quite an involved process.
select.selectionTopNode = function (container, start) {
var range = selectionRange(container.ownerDocument.defaultView);
if (!range) return false;
var node = start ? range.startContainer : range.endContainer;
var offset = start ? range.startOffset : range.endOffset;
// Work around (yet another) bug in Opera's selection model.
if (window.opera && !start && range.endContainer == container && range.endOffset == range.startOffset + 1 &&
container.childNodes[range.startOffset] && isBR(container.childNodes[range.startOffset]))
offset--;
// For text nodes, we look at the node itself if the cursor is
// inside, or at the node before it if the cursor is at the
// start.
if (node.nodeType == 3) {
if (offset > 0)
return topLevelNodeAt(node, container);
else
return topLevelNodeBefore(node, container);
}
// Occasionally, browsers will return the HTML node as
// selection. If the offset is 0, we take the start of the frame
// ('after null'), otherwise, we take the last node.
else if (node.nodeName.toUpperCase() == "HTML") {
return (offset == 1 ? null : container.lastChild);
}
// If the given node is our 'container', we just look up the
// correct node by using the offset.
else if (node == container) {
return (offset == 0) ? null : node.childNodes[offset - 1];
}
// In any other case, we have a regular node. If the cursor is
// at the end of the node, we use the node itself, if it is at
// the start, we use the node before it, and in any other
// case, we look up the child before the cursor and use that.
else {
if (offset == node.childNodes.length)
return topLevelNodeAt(node, container);
else if (offset == 0)
return topLevelNodeBefore(node, container);
else
return topLevelNodeAt(node.childNodes[offset - 1], container);
}
};
select.focusAfterNode = function (node, container) {
var win = container.ownerDocument.defaultView,
range = win.document.createRange();
range.setStartBefore(container.firstChild || container);
// In Opera, setting the end of a range at the end of a line
// (before a BR) will cause the cursor to appear on the next
// line, so we set the end inside of the start node when
// possible.
if (node && !node.firstChild)
range.setEndAfter(node);
else if (node)
range.setEnd(node, node.childNodes.length);
else
range.setEndBefore(container.firstChild || container);
range.collapse(false);
selectRange(range, win);
};
select.somethingSelected = function (win) {
var range = selectionRange(win);
return range && !range.collapsed;
};
function insertNodeAtCursor(window, node) {
var range = selectionRange(window);
if (!range) return;
range.deleteContents();
range.insertNode(node);
webkitLastLineHack(window.document.body);
range = window.document.createRange();
range.selectNode(node);
range.collapse(false);
selectRange(range, window);
}
select.insertNewlineAtCursor = function (window) {
insertNodeAtCursor(window, window.document.createElement("BR"));
};
select.insertTabAtCursor = function (window) {
insertNodeAtCursor(window, window.document.createTextNode(fourSpaces));
};
select.cursorPos = function (container, start) {
var range = selectionRange(window);
if (!range) return;
var topNode = select.selectionTopNode(container, start);
while (topNode && !isBR(topNode))
topNode = topNode.previousSibling;
range = range.cloneRange();
range.collapse(start);
if (topNode)
range.setStartAfter(topNode);
else
range.setStartBefore(container);
return {node: topNode, offset: range.toString().length};
};
select.setCursorPos = function (container, from, to) {
var win = container.ownerDocument.defaultView,
range = win.document.createRange();
function setPoint(node, offset, side) {
if (offset == 0 && node && !node.nextSibling) {
range["set" + side + "After"](node);
return true;
}
if (!node)
node = container.firstChild;
else
node = node.nextSibling;
if (!node) return;
if (offset == 0) {
range["set" + side + "Before"](node);
return true;
}
var backlog = []
function decompose(node) {
if (node.nodeType == 3)
backlog.push(node);
else
forEach(node.childNodes, decompose);
}
while (true) {
while (node && !backlog.length) {
decompose(node);
node = node.nextSibling;
}
var cur = backlog.shift();
if (!cur) return false;
var length = cur.nodeValue.length;
if (length >= offset) {
range["set" + side](cur, offset);
return true;
}
offset -= length;
}
}
to = to || from;
if (setPoint(to.node, to.offset, "End") && setPoint(from.node, from.offset, "Start"))
selectRange(range, win);
};
}
})();
|
Download
