Source: ReactInputSelection.js
import { TEXT_NODE, ELEMENT_NODE } from '../../../HTMLNodeType';
import { getActiveElement } from './getActiveElement';
import { getOffsets, setOffsets } from './ReactDOMSelection';
const isSameOriginFrame = (iframe) => {
try {
return typeof iframe.contentWindow.location.href === 'string';
} catch (err) {
return false;
}
};
const getActiveElementDeep = () => {
let win = window;
let element = getActiveElement();
while (element instanceof win.HTMLIFrameElement) {
if (isSameOriginFrame(element)) {
win = element.contentWindow;
} else {
return element;
}
element = getActiveElement(win.document);
}
return element;
};
const hasSelectionCapabilities = (elem) => {
const nodeName = elem && elem.nodeName && elem.nodeName.toLowerCase();
return (
nodeName &&
((nodeName === 'input' &&
(elem.type === 'text' ||
elem.type === 'search' ||
elem.type === 'tel' ||
elem.type === 'url' ||
elem.type === 'password')) ||
nodeName === 'textarea' ||
elem.contentEditable === 'true')
);
};
const getSelection = (input) => {
let selection;
if ('selectionStart' in input) {
selection = {
start: input.selectionStart,
end: input.selectionEnd,
};
} else {
selection = getOffsets(input);
}
return selection || { start: 0, end: 0 };
};
const getSelectionInformation = () => {
const focusedElem = getActiveElementDeep();
return {
focusedElem: focusedElem,
selectionRange: hasSelectionCapabilities(focusedElem)
? getSelection(focusedElem)
: null,
};
};
const isTextNode = (node) => {
return node && node.nodeType === TEXT_NODE;
};
const containsNode = (outerNode, innerNode) => {
if (!outerNode || !innerNode) {
return false;
} else if (outerNode === innerNode) {
return true;
} else if (isTextNode(outerNode)) {
return false;
} else if (isTextNode(innerNode)) {
return containsNode(outerNode, innerNode.parentNode);
} else if ('contains' in outerNode) {
return outerNode.contains(innerNode);
} else if (outerNode.compareDocumentPosition) {
return !!(outerNode.compareDocumentPosition(innerNode) & 16);
} else {
return false;
}
};
const isInDocument = (node) => {
return (
node &&
node.ownerDocument &&
containsNode(node.ownerDocument.documentElement, node)
);
};
const setSelection = (input, offsets) => {
const start = offsets.start;
let end = offsets.end;
if (end === undefined) {
end = start;
}
if ('selectionStart' in input) {
input.selectionStart = start;
input.selectionEnd = Math.min(end, input.value.length);
} else {
setOffsets(input, offsets);
}
};
const restoreSelection = (priorSelectionInformation) => {
const curFocusedElem = getActiveElementDeep();
const priorFocusedElem = priorSelectionInformation.focusedElem;
const priorSelectionRange = priorSelectionInformation.selectionRange;
if (curFocusedElem !== priorFocusedElem && isInDocument(priorFocusedElem)) {
if (
priorSelectionRange !== null &&
hasSelectionCapabilities(priorFocusedElem)
) {
setSelection(priorFocusedElem, priorSelectionRange);
}
const ancestors = [];
let ancestor = priorFocusedElem;
while ((ancestor = ancestor.parentNode)) {
if (ancestor.nodeType === ELEMENT_NODE) {
ancestors.push({
element: ancestor,
left: ancestor.scrollLeft,
top: ancestor.scrollTop,
});
}
}
if (typeof priorFocusedElem.focus === 'function') {
priorFocusedElem.focus();
}
for (let i = 0; i < ancestors.length; i++) {
const info = ancestors[i];
info.element.scrollLeft = info.left;
info.element.scrollTop = info.top;
}
}
};
export {
getSelectionInformation,
hasSelectionCapabilities,
getSelection,
restoreSelection,
};