/**
* Get the key from the node's nearest offset-aware ancestor.
*/
function findAncestorOffsetKey(node: Node): ?string {
while (node && node !== document.documentElement) {
var key = getSelectionOffsetKeyForNode(node);
if (key != null) {
return key;
}
node = node.parentNode;
}
return null;
}
/**
* Get the key from the node's nearest offset-aware ancestor.
*/
function findAncestorOffsetKey(node: Node): ?string {
let searchNode = node;
while (searchNode && searchNode !== document.documentElement) {
const key = getSelectionOffsetKeyForNode(searchNode);
if (key != null) {
return key;
}
searchNode = searchNode.parentNode;
}
return null;
}
/**
* Identify the last leaf descendant for the given node.
*/
function getLastLeaf(node: any): Node {
while (
node.lastChild &&
// data-blocks has no offset
((node.lastChild instanceof Element &&
node.lastChild.getAttribute('data-blocks') === 'true') ||
getSelectionOffsetKeyForNode(node.lastChild))
) {
node = node.lastChild;
}
return node;
}
function getPointForNonTextNode(
editorRoot: ?HTMLElement,
startNode: Node,
childOffset: number,
): SelectionPoint {
let node = startNode;
var offsetKey: ?string = findAncestorOffsetKey(node);
invariant(
offsetKey != null ||
(editorRoot && (editorRoot === node || editorRoot.firstChild === node)),
'Unknown node in selection range.',
);
// If the editorRoot is the selection, step downward into the content
// wrapper.
if (editorRoot === node) {
node = node.firstChild;
invariant(
node instanceof Element && node.getAttribute('data-contents') === 'true',
'Invalid DraftEditorContents structure.',
);
if (childOffset > 0) {
childOffset = node.childNodes.length;
}
}
// If the child offset is zero and we have an offset key, we're done.
// If there's no offset key because the entire editor is selected,
// find the leftmost ("first") leaf in the tree and use that as the offset
// key.
if (childOffset === 0) {
var key: ?string = null;
if (offsetKey != null) {
key = offsetKey;
} else {
var firstLeaf = getFirstLeaf(node);
key = nullthrows(getSelectionOffsetKeyForNode(firstLeaf));
}
return {key, offset: 0};
}
var nodeBeforeCursor = node.childNodes[childOffset - 1];
var leafKey: ?string = null;
var textLength: ?number = null;
if (!getSelectionOffsetKeyForNode(nodeBeforeCursor)) {
// Our target node may be a leaf or a text node, in which case we're
// already where we want to be and can just use the child's length as
// our offset.
leafKey = nullthrows(offsetKey);
textLength = getTextContentLength(nodeBeforeCursor);
} else {
// Otherwise, we'll look at the child to the left of the cursor and find
// the last leaf node in its subtree.
var lastLeaf = getLastLeaf(nodeBeforeCursor);
leafKey = nullthrows(getSelectionOffsetKeyForNode(lastLeaf));
textLength = getTextContentLength(lastLeaf);
}
return {
key: leafKey,
offset: textLength,
};
}
/**
* Identify the last leaf descendant for the given node.
*/
function getLastLeaf(node: Node): Node {
while (node.lastChild && getSelectionOffsetKeyForNode(node.lastChild)) {
node = node.lastChild;
}
return node;
}