yjs/src/types/AbstractType.js
2019-04-23 20:51:32 +02:00

604 lines
14 KiB
JavaScript

import {
removeEventHandlerListener,
callEventHandlerListeners,
addEventHandlerListener,
createEventHandler,
ItemType,
nextID,
isVisible,
ItemJSON,
ItemBinary,
createID,
getItemCleanStart,
Y, Snapshot, Transaction, EventHandler, YEvent, AbstractItem, // eslint-disable-line
} from '../internals.js'
import * as map from 'lib0/map.js'
import * as iterator from 'lib0/iterator.js'
import * as error from 'lib0/error.js'
import * as encoding from 'lib0/encoding.js' // eslint-disable-line
/**
* Call event listeners with an event. This will also add an event to all
* parents (for `.observeDeep` handlers).
* @private
*
* @template EventType
* @param {AbstractType<EventType>} type
* @param {Transaction} transaction
* @param {EventType} event
*/
export const callTypeObservers = (type, transaction, event) => {
callEventHandlerListeners(type._eH, event, transaction)
const changedParentTypes = transaction.changedParentTypes
while (true) {
// @ts-ignore
map.setIfUndefined(changedParentTypes, type, () => []).push(event)
if (type._item === null) {
break
}
type = type._item.parent
}
}
/**
* @template EventType
* Abstract Yjs Type class
*/
export class AbstractType {
constructor () {
/**
* @type {ItemType|null}
*/
this._item = null
/**
* @private
* @type {Map<string,AbstractItem>}
*/
this._map = new Map()
/**
* @private
* @type {AbstractItem|null}
*/
this._start = null
/**
* @private
* @type {Y|null}
*/
this._y = null
this._length = 0
/**
* Event handlers
* @type {EventHandler<EventType,Transaction>}
*/
this._eH = createEventHandler()
/**
* Deep event handlers
* @type {EventHandler<Array<YEvent>,Transaction>}
*/
this._dEH = createEventHandler()
}
/**
* Integrate this type into the Yjs instance.
*
* * Save this struct in the os
* * This type is sent to other client
* * Observer functions are fired
*
* @param {Y} y The Yjs instance
* @param {ItemType|null} item
* @private
*/
_integrate (y, item) {
this._y = y
this._item = item
}
/**
* @return {AbstractType<EventType>}
* @private
*/
_copy () {
throw new Error('unimplemented')
}
/**
* @param {encoding.Encoder} encoder
* @private
*/
_write (encoder) { }
/**
* The first non-deleted item
*/
get _first () {
let n = this._start
while (n !== null && n.deleted) {
n = n.right
}
return n
}
/**
* Creates YEvent and calls all type observers.
* Must be implemented by each type.
*
* @param {Transaction} transaction
* @param {Set<null|string>} parentSubs Keys changed on this type. `null` if list was modified.
*
* @private
*/
_callObserver (transaction, parentSubs) { /* skip if no type is specified */ }
/**
* Observe all events that are created on this type.
*
* @param {function(EventType, Transaction):void} f Observer function
*/
observe (f) {
addEventHandlerListener(this._eH, f)
}
/**
* Observe all events that are created by this type and its children.
*
* @param {function(Array<YEvent>,Transaction):void} f Observer function
*/
observeDeep (f) {
addEventHandlerListener(this._dEH, f)
}
/**
* Unregister an observer function.
*
* @param {function(EventType,Transaction):void} f Observer function
*/
unobserve (f) {
removeEventHandlerListener(this._eH, f)
}
/**
* Unregister an observer function.
*
* @param {function(Array<YEvent>,Transaction):void} f Observer function
*/
unobserveDeep (f) {
removeEventHandlerListener(this._dEH, f)
}
/**
* @abstract
* @return {Object | Array | number | string}
*/
toJSON () {}
}
/**
* @param {AbstractType<any>} type
* @return {Array<any>}
*
* @private
* @function
*/
export const typeArrayToArray = type => {
const cs = []
let n = type._start
while (n !== null) {
if (n.countable && !n.deleted) {
const c = n.getContent()
for (let i = 0; i < c.length; i++) {
cs.push(c[i])
}
}
n = n.right
}
return cs
}
/**
* @param {AbstractType<any>} type
* @param {Snapshot} snapshot
* @return {Array<any>}
*
* @private
* @function
*/
export const typeArrayToArraySnapshot = (type, snapshot) => {
const cs = []
let n = type._start
while (n !== null) {
if (n.countable && isVisible(n, snapshot)) {
const c = n.getContent()
for (let i = 0; i < c.length; i++) {
cs.push(c[i])
}
}
n = n.right
}
return cs
}
/**
* Executes a provided function on once on overy element of this YArray.
*
* @param {AbstractType<any>} type
* @param {function(any,number,AbstractType<any>):void} f A function to execute on every element of this YArray.
*
* @private
* @function
*/
export const typeArrayForEach = (type, f) => {
let index = 0
let n = type._start
while (n !== null) {
if (n.countable && !n.deleted) {
const c = n.getContent()
for (let i = 0; i < c.length; i++) {
f(c[i], index++, type)
}
}
n = n.right
}
}
/**
* @template C,R
* @param {AbstractType<any>} type
* @param {function(C,number,AbstractType<any>):R} f
* @return {Array<R>}
*
* @private
* @function
*/
export const typeArrayMap = (type, f) => {
/**
* @type {Array<any>}
*/
const result = []
typeArrayForEach(type, (c, i) => {
result.push(f(c, i, type))
})
return result
}
/**
* @param {AbstractType<any>} type
* @return {IterableIterator<any>}
*
* @private
* @function
*/
export const typeArrayCreateIterator = type => {
let n = type._start
/**
* @type {Array<any>|null}
*/
let currentContent = null
let currentContentIndex = 0
return {
[Symbol.iterator] () {
return this
},
next: () => {
// find some content
if (currentContent === null) {
while (n !== null && n.deleted) {
n = n.right
}
}
// check if we reached the end, no need to check currentContent, because it does not exist
if (n === null) {
return {
done: true,
value: undefined
}
}
// currentContent could exist from the last iteration
if (currentContent === null) {
// we found n, so we can set currentContent
currentContent = n.getContent()
currentContentIndex = 0
n = n.right // we used the content of n, now iterate to next
}
const value = currentContent[currentContentIndex++]
// check if we need to empty currentContent
if (currentContent.length <= currentContentIndex) {
currentContent = null
}
return {
done: false,
value
}
}
}
}
/**
* Executes a provided function on once on overy element of this YArray.
* Operates on a snapshotted state of the document.
*
* @param {AbstractType<any>} type
* @param {function(any,number,AbstractType<any>):void} f A function to execute on every element of this YArray.
* @param {Snapshot} snapshot
*
* @private
* @function
*/
export const typeArrayForEachSnapshot = (type, f, snapshot) => {
let index = 0
let n = type._start
while (n !== null) {
if (n.countable && isVisible(n, snapshot)) {
const c = n.getContent()
for (let i = 0; i < c.length; i++) {
f(c[i], index++, type)
}
}
n = n.right
}
}
/**
* @param {AbstractType<any>} type
* @param {number} index
* @return {any}
*
* @private
* @function
*/
export const typeArrayGet = (type, index) => {
for (let n = type._start; n !== null; n = n.right) {
if (!n.deleted && n.countable) {
if (index < n.length) {
return n.getContent()[index]
}
index -= n.length
}
}
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {AbstractItem?} referenceItem
* @param {Array<Object<string,any>|Array<any>|number|string|ArrayBuffer>} content
*
* @private
* @function
*/
export const typeArrayInsertGenericsAfter = (transaction, parent, referenceItem, content) => {
let left = referenceItem
const right = referenceItem === null ? parent._start : referenceItem.right
/**
* @type {Array<Object|Array|number>}
*/
let jsonContent = []
const packJsonContent = () => {
if (jsonContent.length > 0) {
left = new ItemJSON(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, jsonContent)
left.integrate(transaction)
jsonContent = []
}
}
content.forEach(c => {
switch (c.constructor) {
case Number:
case Object:
case Array:
case String:
jsonContent.push(c)
break
default:
packJsonContent()
switch (c.constructor) {
case ArrayBuffer:
// @ts-ignore c is definitely an ArrayBuffer
left = new ItemBinary(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, c)
// @ts-ignore
left.integrate(transaction)
break
default:
if (c instanceof AbstractType) {
left = new ItemType(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, c)
left.integrate(transaction)
} else {
throw new Error('Unexpected content type in insert operation')
}
}
}
})
packJsonContent()
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {number} index
* @param {Array<Object<string,any>|Array<any>|number|string|ArrayBuffer>} content
*
* @private
* @function
*/
export const typeArrayInsertGenerics = (transaction, parent, index, content) => {
if (index === 0) {
return typeArrayInsertGenericsAfter(transaction, parent, null, content)
}
let n = parent._start
for (; n !== null; n = n.right) {
if (!n.deleted && n.countable) {
if (index <= n.length) {
if (index < n.length) {
// insert in-between
getItemCleanStart(transaction, transaction.y.store, createID(n.id.client, n.id.clock + index))
}
break
}
index -= n.length
}
}
return typeArrayInsertGenericsAfter(transaction, parent, n, content)
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {number} index
* @param {number} length
*
* @private
* @function
*/
export const typeArrayDelete = (transaction, parent, index, length) => {
if (length === 0) { return }
let n = parent._start
// compute the first item to be deleted
for (; n !== null; n = n.right) {
if (!n.deleted && n.countable) {
if (index <= n.length) {
if (index < n.length && index > 0) {
n = getItemCleanStart(transaction, transaction.y.store, createID(n.id.client, n.id.clock + index))
}
break
}
index -= n.length
}
}
// delete all items until done
while (length > 0 && n !== null) {
if (!n.deleted) {
if (length < n.length) {
getItemCleanStart(transaction, transaction.y.store, createID(n.id.client, n.id.clock + length))
}
n.delete(transaction)
length -= n.length
}
n = n.right
}
if (length > 0) {
throw error.create('array length exceeded')
}
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {string} key
*
* @private
* @function
*/
export const typeMapDelete = (transaction, parent, key) => {
const c = parent._map.get(key)
if (c !== undefined) {
c.delete(transaction)
}
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {string} key
* @param {Object|number|Array<any>|string|ArrayBuffer|AbstractType<any>} value
*
* @private
* @function
*/
export const typeMapSet = (transaction, parent, key, value) => {
const left = parent._map.get(key) || null
if (value == null) {
new ItemJSON(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, [value]).integrate(transaction)
return
}
switch (value.constructor) {
case Number:
case Object:
case Array:
case String:
new ItemJSON(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, [value]).integrate(transaction)
break
case ArrayBuffer:
new ItemBinary(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, value).integrate(transaction)
break
default:
if (value instanceof AbstractType) {
new ItemType(nextID(transaction), left, left === null ? null : left.lastId, null, null, parent, key, value).integrate(transaction)
} else {
throw new Error('Unexpected content type')
}
}
}
/**
* @param {AbstractType<any>} parent
* @param {string} key
* @return {Object<string,any>|number|Array<any>|string|ArrayBuffer|AbstractType<any>|undefined}
*
* @private
* @function
*/
export const typeMapGet = (parent, key) => {
const val = parent._map.get(key)
return val !== undefined && !val.deleted ? val.getContent()[0] : undefined
}
/**
* @param {AbstractType<any>} parent
* @return {Object<string,Object<string,any>|number|Array<any>|string|ArrayBuffer|AbstractType<any>|undefined>}
*
* @private
* @function
*/
export const typeMapGetAll = (parent) => {
/**
* @type {Object<string,any>}
*/
let res = {}
for (const [key, value] of parent._map) {
if (!value.deleted) {
res[key] = value.getContent()[value.length - 1]
}
}
return res
}
/**
* @param {AbstractType<any>} parent
* @param {string} key
* @return {boolean}
*
* @private
* @function
*/
export const typeMapHas = (parent, key) => {
const val = parent._map.get(key)
return val !== undefined && !val.deleted
}
/**
* @param {AbstractType<any>} parent
* @param {string} key
* @param {Snapshot} snapshot
* @return {Object<string,any>|number|Array<any>|string|ArrayBuffer|AbstractType<any>|undefined}
*
* @private
* @function
*/
export const typeMapGetSnapshot = (parent, key, snapshot) => {
let v = parent._map.get(key) || null
while (v !== null && (!snapshot.sm.has(v.id.client) || v.id.clock >= (snapshot.sm.get(v.id.client) || 0))) {
v = v.left
}
return v !== null && isVisible(v, snapshot) ? v.getContent()[v.length - 1] : undefined
}
/**
* @param {Map<string,AbstractItem>} map
* @return {IterableIterator<Array<any>>}
*
* @private
* @function
*/
export const createMapIterator = map => iterator.iteratorFilter(map.entries(), entry => !entry[1].deleted)