substance
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Substance is a JavaScript library for web-based content editing. It provides building blocks for realizing custom text editors and web-based publishing system. It is developed to power our online editing platform [Substance](http://substance.io).
412 lines (378 loc) • 13.6 kB
JavaScript
import DefaultDOMElement from '../dom/DefaultDOMElement'
import Component from '../dom/Component'
import platform from '../util/platform'
import Coordinate from '../model/Coordinate'
import Range from '../model/Range'
import TextPropertyComponent from './TextPropertyComponent'
import IsolatedNodeComponent from './IsolatedNodeComponent'
const DEBUG = false
/*
A class that maps DOM selections to model selections.
There are some difficulties with mapping model selections:
1. DOM selections can not model discontinuous selections.
2. Not all positions reachable via ContentEditable can be mapped to model selections. For instance,
there are extra positions before and after non-editable child elements.
3. Some native cursor behaviors need to be overidden.
@param {Editor} Editor component
*/
export default class DOMSelection {
/**
*
*/
constructor (editor) {
this.editor = editor
if (platform.inBrowser) {
this.wRange = window.document.createRange()
}
// keeping the last DOM and Model coordinates
// TODO: why are we doing this?
this.state = { dom: null, model: null }
}
/**
Create a model selection by mapping the current DOM selection
to model coordinates.
@param {object} options
- `direction`: `left` or `right`; a hint for disambiguations, used by Surface during cursor navigation.
@returns {model/Selection}
*/
getSelection (options) {
// HACK: ignore this if not Browser (e.g. when running the test suite in node)
if (!platform.inBrowser) return
const range = this.mapDOMSelection(options)
const doc = this.editor.getDocument()
// TODO: consolidate
return doc._createSelectionFromRange(range)
}
getSelectionForDOMRange (wrange) {
const range = this.mapDOMRange(wrange)
const doc = this.editor.getDocument()
return doc._createSelectionFromRange(range)
}
/*
Maps the current DOM selection to a model range.
@param {object} [options]
- `direction`: `left` or `right`; a hint for disambiguations, used by Surface during cursor navigation.
@returns {model/Range}
*/
mapDOMSelection (options) {
const wSel = window.getSelection()
const state = this.state
let range
// Use this log whenever the mapping goes wrong to analyze what
// is actually being provided by the browser
if (DEBUG) console.info('DOM->Model: ', wSel.anchorNode, wSel.anchorOffset, wSel.focusNode, wSel.focusOffset)
if (wSel.rangeCount === 0) return _null()
const anchorNode = DefaultDOMElement.wrapNativeElement(wSel.anchorNode)
if (wSel.isCollapsed) {
const coor = this._getCoordinate(anchorNode, wSel.anchorOffset, options)
if (!coor) return _null()
range = _createRange({
start: coor,
end: coor
})
} else {
const focusNode = DefaultDOMElement.wrapNativeElement(wSel.focusNode)
range = this._getRange(anchorNode, wSel.anchorOffset, focusNode, wSel.focusOffset, options)
}
if (DEBUG) console.info('DOM->Model: range ', range ? range.toString() : null)
state.model = range
return range
function _null () {
state.dom = null
state.model = null
return null
}
}
/**
Transfer a given model selection into the DOM.
@param {model/Selection} sel
*/
setSelection (sel) {
// HACK: ignore this if not Browser (e.g. when running the test suite in node)
if (!platform.inBrowser) return
const state = this.state
const wSel = window.getSelection()
const wRange = this.wRange
if (!sel || sel.isNull()) return this.clear()
// console.log('### DOMSelection: setting selection', sel.toString());
let { start, end } = this.mapModelToDOMCoordinates(sel)
if (!start) return this.clear()
if (sel.isReverse()) {
[start, end] = [end, start]
}
state.dom = {
anchorNode: start.container,
anchorOffset: start.offset,
focusNode: end.container,
focusOffset: end.offset
}
// HACK: sometimes it happens that this fails
// doing a try-finally lets the debugger still stop, but continue
try {
_set(state.dom)
} finally {}
function _set ({ anchorNode, anchorOffset, focusNode, focusOffset }) {
wSel.removeAllRanges()
wRange.setStart(anchorNode, anchorOffset)
wRange.setEnd(anchorNode, anchorOffset)
wSel.addRange(wRange)
if (focusNode !== anchorOffset || focusOffset !== anchorOffset) {
wSel.extend(focusNode, focusOffset)
}
}
}
mapModelToDOMCoordinates (sel) {
if (DEBUG) console.info('Model->DOM: sel =', sel.toString())
let rootEl
const surface = this.editor.getSurfaceManager().getSurface(sel.surfaceId)
if (!surface) {
console.warn('No surface:', sel.surfaceId)
rootEl = this.editor.getElement()
} else {
rootEl = surface.el
}
if (sel.isNull() || sel.isCustomSelection()) {
return {}
}
let start, end
if (sel.isPropertySelection() || sel.isContainerSelection()) {
start = this._getDOMCoordinate(rootEl, sel.start)
if (!start) {
console.warn('FIXME: selection seems to be invalid.')
return {}
}
if (sel.isCollapsed()) {
end = start
} else {
end = this._getDOMCoordinate(rootEl, sel.end)
if (!end) {
console.warn('FIXME: selection seems to be invalid.')
return {}
}
}
} else if (sel.isNodeSelection()) {
const comp = Component.unwrap(rootEl.find('*[data-id="' + sel.getNodeId() + '"]'))
if (!comp) {
console.error('Could not find component with id', sel.getNodeId())
return {}
}
if (comp._isIsolatedNodeComponent) {
const coors = IsolatedNodeComponent.getDOMCoordinates(comp, sel)
start = coors.start
end = coors.end
// Note: ATM we do not render collapsed NodeSelections differently
// if (sel.isAfter()) start = end
// else if (sel.isBefore()) end = start
} else {
const _nodeEl = comp.el
start = {
container: _nodeEl.getNativeElement(),
offset: 0
}
end = {
container: _nodeEl.getNativeElement(),
offset: _nodeEl.getChildCount()
}
}
}
if (DEBUG) console.info('Model->DOM:', start.container, start.offset, end.container, end.offset, 'isReverse?', sel.isReverse())
return { start, end }
}
_getDOMCoordinate (rootEl, coor) {
let domCoor = null
let comp
if (coor.isNodeCoordinate()) {
comp = Component.unwrap(rootEl.find('*[data-id="' + coor.getNodeId() + '"]'))
if (comp) {
if (comp._isIsolatedNodeComponent) {
domCoor = IsolatedNodeComponent.getDOMCoordinate(comp, coor)
} else {
let domOffset = 0
if (coor.offset > 0) {
domOffset = comp.getChildCount()
}
domCoor = {
container: comp.getNativeElement(),
offset: domOffset
}
}
}
} else {
comp = Component.unwrap(rootEl.find('.sc-text-property[data-path="' + coor.path.join('.') + '"]'))
if (comp) {
domCoor = comp.getDOMCoordinate(coor.offset)
}
}
return domCoor
}
/*
Map a DOM range to a model range.
@param {Range} range
@returns {model/Range}
*/
mapDOMRange (wRange, options) {
return this._getRange(
DefaultDOMElement.wrapNativeElement(wRange.startContainer),
wRange.startOffset,
DefaultDOMElement.wrapNativeElement(wRange.endContainer),
wRange.endOffset, options)
}
/*
Clear the DOM selection.
*/
clear () {
window.getSelection().removeAllRanges()
this.state.dom = null
this.state.model = null
}
collapse (dir) {
const wSel = window.getSelection()
let wRange
if (wSel.rangeCount > 0) {
wRange = wSel.getRangeAt(0)
wRange.collapse(dir === 'left')
wSel.removeAllRanges()
wSel.addRange(wRange)
}
}
select (el) {
const wSel = window.getSelection()
const wRange = window.document.createRange()
wRange.selectNode(el.getNativeElement())
wSel.removeAllRanges()
wSel.addRange(wRange)
}
extend (el, offset) {
const wSel = window.getSelection()
wSel.extend(el.getNativeElement(), offset)
}
setCursor (el, offset) {
const wSel = window.getSelection()
const wRange = window.document.createRange()
wRange.setStart(el.getNativeElement(), offset)
wSel.removeAllRanges()
wSel.addRange(wRange)
}
/*
Extract a model range from given DOM elements.
@param {Node} anchorNode
@param {number} anchorOffset
@param {Node} focusNode
@param {number} focusOffset
@returns {model/Range}
*/
_getRange (anchorNode, anchorOffset, focusNode, focusOffset, options = {}) {
const isReverse = DefaultDOMElement.isReverse(anchorNode, anchorOffset, focusNode, focusOffset)
const isCollapsed = (anchorNode === focusNode && anchorOffset === focusOffset)
let start, end
if (isCollapsed) {
start = end = this._getCoordinate(anchorNode, anchorOffset, options)
} else {
start = this._getCoordinate(anchorNode, anchorOffset, { direction: isReverse ? 'right' : 'left' })
end = this._getCoordinate(focusNode, focusOffset, options)
}
if (start && end) {
return _createRange({ start, end, isReverse })
} else {
return null
}
}
/*
Map a DOM coordinate to a model coordinate.
@param {Node} node
@param {number} offset
@param {object} options
@param {object} [options]
- `direction`: `left` or `right`; a hint for disambiguation.
@returns {model/Coordinate}
@info
`options.direction` can be used to control the result when this function is called
after cursor navigation. The root problem is that we are using ContentEditable on
Container level (as opposed to TextProperty level). The native ContentEditable allows
cursor positions which do not make sense in the model sense.
For example,
```
<div contenteditable=true>
<p data-path="p1.content">foo</p>
<img>
<p data-path="p1.content">bar</p>
</div>
```
would allow to set the cursor directly before or after the image, which
we want to prevent, as it is not a valid insert position for text.
Instead, if we find the DOM selection in such a situation, then we map it to the
closest valid model address. And this depends on the direction of movement.
Moving `left` would provide the previous address, `right` would provide the next address.
The default direction is `right`.
*/
_getCoordinate (nodeEl, offset, options = {}) {
let coor = null
// this deals with a cursor in a TextProperty
if (!coor) {
coor = TextPropertyComponent.getCoordinate(this.editor.getElement(), nodeEl, offset)
}
const comp = Component.unwrap(nodeEl)
if (!coor && comp) {
// let IsolatedNodeComponent figure out where the selection is
if (comp.context.isolatedNodeComponent) {
coor = IsolatedNodeComponent.getCoordinate(nodeEl, options)
}
}
// Edge-cases: These handlers are hacked so that the case is covered,
// not solved 'elegantly'
if (!coor) {
// as in #354: sometimes anchor or focus is the surface itself
if (comp && comp._isContainerEditor) {
const childIdx = (offset === 0) ? 0 : offset - 1
const isBefore = (offset === 0)
const doc = comp.getDocument()
const containerPath = comp.getContainerPath()
const nodeIds = doc.get(containerPath)
const childNode = doc.get(nodeIds[childIdx])
const childComp = comp.getChildAt(childIdx)
coor = new Coordinate([childNode.id], isBefore ? 0 : 1)
coor._comp = childComp
// sometimes anchor or focus is a Node component with TextPropertyComponents as children (all TextNode Components)
} else if (nodeEl.isElementNode() && nodeEl.getChildCount() > 0) {
const child = (offset > 0) ? nodeEl.getChildAt(offset - 1) : nodeEl.firstChild
let prop
const childComp = Component.unwrap(child)
if (childComp && childComp._isTextPropertyComponent) {
prop = child
}
if (prop) {
coor = TextPropertyComponent.getCoordinate(nodeEl, prop, (offset > 0) ? prop.getChildCount() : 0)
}
}
}
return coor
}
}
/*
Helper for creating a model range correctly
as for model/Range start should be before end.
In contrast to that, DOM selections are described with anchor and focus coordinates,
i.e. bearing the information of direction implicitly.
To simplify the implementation we treat anchor and focus equally
and only at the end exploit the fact deriving an isReverse flag
and bringing start and end in the correct order.
*/
function _createRange ({ start, end, isReverse }) {
if (isReverse) {
[start, end] = [end, start]
}
if (!start._comp || !end._comp) {
console.error('FIXME: getCoordinate() should provide a component instance')
return null
}
const surface = start._comp.context.surface
if (!surface) {
console.error('FIXME: Editable components should have their surface in the context')
return null
}
if (surface !== end._comp.context.surface) {
console.error('Coordinates are within two different surfaces. Can not create a selection.')
return null
}
return new Range(start, end, isReverse, surface.getContainerPath(), surface.id)
}