yjs/src/utils/UndoManager.js
2025-03-04 14:52:19 +01:00

401 lines
14 KiB
JavaScript

import {
mergeDeleteSets,
iterateDeletedStructs,
keepItem,
transact,
createID,
redoItem,
isParentOf,
followRedone,
getItemCleanStart,
isDeleted,
addToDeleteSet,
YEvent, Transaction, Doc, Item, GC, DeleteSet, AbstractType // eslint-disable-line
} from '../internals.js'
import * as time from 'lib0/time'
import * as array from 'lib0/array'
import * as logging from 'lib0/logging'
import { ObservableV2 } from 'lib0/observable'
export class StackItem {
/**
* @param {DeleteSet} deletions
* @param {DeleteSet} insertions
*/
constructor (deletions, insertions) {
this.insertions = insertions
this.deletions = deletions
/**
* Use this to save and restore metadata like selection range
*/
this.meta = new Map()
}
}
/**
* @param {Transaction} tr
* @param {UndoManager} um
* @param {StackItem} stackItem
*/
const clearUndoManagerStackItem = (tr, um, stackItem) => {
iterateDeletedStructs(tr, stackItem.deletions, item => {
if (item instanceof Item && um.scope.some(type => type === tr.doc || isParentOf(/** @type {AbstractType<any>} */ (type), item))) {
keepItem(item, false)
}
})
}
/**
* @param {UndoManager} undoManager
* @param {Array<StackItem>} stack
* @param {'undo'|'redo'} eventType
* @return {StackItem?}
*/
const popStackItem = (undoManager, stack, eventType) => {
/**
* Keep a reference to the transaction so we can fire the event with the changedParentTypes
* @type {any}
*/
let _tr = null
const doc = undoManager.doc
const scope = undoManager.scope
transact(doc, transaction => {
while (stack.length > 0 && undoManager.currStackItem === null) {
const store = doc.store
const stackItem = /** @type {StackItem} */ (stack.pop())
/**
* @type {Set<Item>}
*/
const itemsToRedo = new Set()
/**
* @type {Array<Item>}
*/
const itemsToDelete = []
let performedChange = false
iterateDeletedStructs(transaction, stackItem.insertions, struct => {
if (struct instanceof Item) {
if (struct.redone !== null) {
let { item, diff } = followRedone(store, struct.id)
if (diff > 0) {
item = getItemCleanStart(transaction, createID(item.id.client, item.id.clock + diff))
}
struct = item
}
if (!struct.deleted && scope.some(type => type === transaction.doc || isParentOf(/** @type {AbstractType<any>} */ (type), /** @type {Item} */ (struct)))) {
itemsToDelete.push(struct)
}
}
})
iterateDeletedStructs(transaction, stackItem.deletions, struct => {
if (
struct instanceof Item &&
scope.some(type => type === transaction.doc || isParentOf(/** @type {AbstractType<any>} */ (type), struct)) &&
// Never redo structs in stackItem.insertions because they were created and deleted in the same capture interval.
!isDeleted(stackItem.insertions, struct.id)
) {
itemsToRedo.add(struct)
}
})
itemsToRedo.forEach(struct => {
performedChange = redoItem(transaction, struct, itemsToRedo, stackItem.insertions, undoManager.ignoreRemoteMapChanges, undoManager) !== null || performedChange
})
// We want to delete in reverse order so that children are deleted before
// parents, so we have more information available when items are filtered.
for (let i = itemsToDelete.length - 1; i >= 0; i--) {
const item = itemsToDelete[i]
if (undoManager.deleteFilter(item)) {
item.delete(transaction)
performedChange = true
}
}
undoManager.currStackItem = performedChange ? stackItem : null
}
transaction.changed.forEach((subProps, type) => {
// destroy search marker if necessary
if (subProps.has(null) && type._searchMarker) {
type._searchMarker.length = 0
}
})
_tr = transaction
}, undoManager)
const res = undoManager.currStackItem
if (res != null) {
const changedParentTypes = _tr.changedParentTypes
undoManager.emit('stack-item-popped', [{ stackItem: res, type: eventType, changedParentTypes, origin: undoManager }, undoManager])
undoManager.currStackItem = null
}
return res
}
/**
* @typedef {Object} UndoManagerOptions
* @property {number} [UndoManagerOptions.captureTimeout=500]
* @property {function(Transaction):boolean} [UndoManagerOptions.captureTransaction] Do not capture changes of a Transaction if result false.
* @property {function(Item):boolean} [UndoManagerOptions.deleteFilter=()=>true] Sometimes
* it is necessary to filter what an Undo/Redo operation can delete. If this
* filter returns false, the type/item won't be deleted even it is in the
* undo/redo scope.
* @property {Set<any>} [UndoManagerOptions.trackedOrigins=new Set([null])]
* @property {boolean} [ignoreRemoteMapChanges] Experimental. By default, the UndoManager will never overwrite remote changes. Enable this property to enable overwriting remote changes on key-value changes (Y.Map, properties on Y.Xml, etc..).
* @property {Doc} [doc] The document that this UndoManager operates on. Only needed if typeScope is empty.
*/
/**
* @typedef {Object} StackItemEvent
* @property {StackItem} StackItemEvent.stackItem
* @property {any} StackItemEvent.origin
* @property {'undo'|'redo'} StackItemEvent.type
* @property {Map<AbstractType<YEvent<any>>,Array<YEvent<any>>>} StackItemEvent.changedParentTypes
*/
/**
* Fires 'stack-item-added' event when a stack item was added to either the undo- or
* the redo-stack. You may store additional stack information via the
* metadata property on `event.stackItem.meta` (it is a `Map` of metadata properties).
* Fires 'stack-item-popped' event when a stack item was popped from either the
* undo- or the redo-stack. You may restore the saved stack information from `event.stackItem.meta`.
*
* @extends {ObservableV2<{'stack-item-added':function(StackItemEvent, UndoManager):void, 'stack-item-popped': function(StackItemEvent, UndoManager):void, 'stack-cleared': function({ undoStackCleared: boolean, redoStackCleared: boolean }):void, 'stack-item-updated': function(StackItemEvent, UndoManager):void }>}
*/
export class UndoManager extends ObservableV2 {
/**
* @param {Doc|AbstractType<any>|Array<AbstractType<any>>} typeScope Limits the scope of the UndoManager. If this is set to a ydoc instance, all changes on that ydoc will be undone. If set to a specific type, only changes on that type or its children will be undone. Also accepts an array of types.
* @param {UndoManagerOptions} options
*/
constructor (typeScope, {
captureTimeout = 500,
captureTransaction = _tr => true,
deleteFilter = () => true,
trackedOrigins = new Set([null]),
ignoreRemoteMapChanges = false,
doc = /** @type {Doc} */ (array.isArray(typeScope) ? typeScope[0].doc : typeScope instanceof Doc ? typeScope : typeScope.doc)
} = {}) {
super()
/**
* @type {Array<AbstractType<any> | Doc>}
*/
this.scope = []
this.doc = doc
this.addToScope(typeScope)
this.deleteFilter = deleteFilter
trackedOrigins.add(this)
this.trackedOrigins = trackedOrigins
this.captureTransaction = captureTransaction
/**
* @type {Array<StackItem>}
*/
this.undoStack = []
/**
* @type {Array<StackItem>}
*/
this.redoStack = []
/**
* Whether the client is currently undoing (calling UndoManager.undo)
*
* @type {boolean}
*/
this.undoing = false
this.redoing = false
/**
* The currently popped stack item if UndoManager.undoing or UndoManager.redoing
*
* @type {StackItem|null}
*/
this.currStackItem = null
this.lastChange = 0
this.ignoreRemoteMapChanges = ignoreRemoteMapChanges
this.captureTimeout = captureTimeout
/**
* @param {Transaction} transaction
*/
this.afterTransactionHandler = transaction => {
// Only track certain transactions
if (
!this.captureTransaction(transaction) ||
!this.scope.some(type => transaction.changedParentTypes.has(/** @type {AbstractType<any>} */ (type)) || type === this.doc) ||
(!this.trackedOrigins.has(transaction.origin) && (!transaction.origin || !this.trackedOrigins.has(transaction.origin.constructor)))
) {
return
}
const undoing = this.undoing
const redoing = this.redoing
const stack = undoing ? this.redoStack : this.undoStack
if (undoing) {
this.stopCapturing() // next undo should not be appended to last stack item
} else if (!redoing) {
// neither undoing nor redoing: delete redoStack
this.clear(false, true)
}
const insertions = new DeleteSet()
transaction.afterState.forEach((endClock, client) => {
const startClock = transaction.beforeState.get(client) || 0
const len = endClock - startClock
if (len > 0) {
addToDeleteSet(insertions, client, startClock, len)
}
})
const now = time.getUnixTime()
let didAdd = false
if (this.lastChange > 0 && now - this.lastChange < this.captureTimeout && stack.length > 0 && !undoing && !redoing) {
// append change to last stack op
const lastOp = stack[stack.length - 1]
lastOp.deletions = mergeDeleteSets([lastOp.deletions, transaction.deleteSet])
lastOp.insertions = mergeDeleteSets([lastOp.insertions, insertions])
} else {
// create a new stack op
stack.push(new StackItem(transaction.deleteSet, insertions))
didAdd = true
}
if (!undoing && !redoing) {
this.lastChange = now
}
// make sure that deleted structs are not gc'd
iterateDeletedStructs(transaction, transaction.deleteSet, /** @param {Item|GC} item */ item => {
if (item instanceof Item && this.scope.some(type => type === transaction.doc || isParentOf(/** @type {AbstractType<any>} */ (type), item))) {
keepItem(item, true)
}
})
/**
* @type {[StackItemEvent, UndoManager]}
*/
const changeEvent = [{ stackItem: stack[stack.length - 1], origin: transaction.origin, type: undoing ? 'redo' : 'undo', changedParentTypes: transaction.changedParentTypes }, this]
if (didAdd) {
this.emit('stack-item-added', changeEvent)
} else {
this.emit('stack-item-updated', changeEvent)
}
}
this.doc.on('afterTransaction', this.afterTransactionHandler)
this.doc.on('destroy', () => {
this.destroy()
})
}
/**
* Extend the scope.
*
* @param {Array<AbstractType<any> | Doc> | AbstractType<any> | Doc} ytypes
*/
addToScope (ytypes) {
const tmpSet = new Set(this.scope)
ytypes = array.isArray(ytypes) ? ytypes : [ytypes]
ytypes.forEach(ytype => {
if (!tmpSet.has(ytype)) {
tmpSet.add(ytype)
if (ytype instanceof AbstractType ? ytype.doc !== this.doc : ytype !== this.doc) logging.warn('[yjs#509] Not same Y.Doc') // use MultiDocUndoManager instead. also see https://github.com/yjs/yjs/issues/509
this.scope.push(ytype)
}
})
}
/**
* @param {any} origin
*/
addTrackedOrigin (origin) {
this.trackedOrigins.add(origin)
}
/**
* @param {any} origin
*/
removeTrackedOrigin (origin) {
this.trackedOrigins.delete(origin)
}
clear (clearUndoStack = true, clearRedoStack = true) {
if ((clearUndoStack && this.canUndo()) || (clearRedoStack && this.canRedo())) {
this.doc.transact(tr => {
if (clearUndoStack) {
this.undoStack.forEach(item => clearUndoManagerStackItem(tr, this, item))
this.undoStack = []
}
if (clearRedoStack) {
this.redoStack.forEach(item => clearUndoManagerStackItem(tr, this, item))
this.redoStack = []
}
this.emit('stack-cleared', [{ undoStackCleared: clearUndoStack, redoStackCleared: clearRedoStack }])
})
}
}
/**
* UndoManager merges Undo-StackItem if they are created within time-gap
* smaller than `options.captureTimeout`. Call `um.stopCapturing()` so that the next
* StackItem won't be merged.
*
*
* @example
* // without stopCapturing
* ytext.insert(0, 'a')
* ytext.insert(1, 'b')
* um.undo()
* ytext.toString() // => '' (note that 'ab' was removed)
* // with stopCapturing
* ytext.insert(0, 'a')
* um.stopCapturing()
* ytext.insert(0, 'b')
* um.undo()
* ytext.toString() // => 'a' (note that only 'b' was removed)
*
*/
stopCapturing () {
this.lastChange = 0
}
/**
* Undo last changes on type.
*
* @return {StackItem?} Returns StackItem if a change was applied
*/
undo () {
this.undoing = true
let res
try {
res = popStackItem(this, this.undoStack, 'undo')
} finally {
this.undoing = false
}
return res
}
/**
* Redo last undo operation.
*
* @return {StackItem?} Returns StackItem if a change was applied
*/
redo () {
this.redoing = true
let res
try {
res = popStackItem(this, this.redoStack, 'redo')
} finally {
this.redoing = false
}
return res
}
/**
* Are undo steps available?
*
* @return {boolean} `true` if undo is possible
*/
canUndo () {
return this.undoStack.length > 0
}
/**
* Are redo steps available?
*
* @return {boolean} `true` if redo is possible
*/
canRedo () {
return this.redoStack.length > 0
}
destroy () {
this.trackedOrigins.delete(this)
this.doc.off('afterTransaction', this.afterTransactionHandler)
super.destroy()
}
}