yjs/src/types/YText.js
2020-01-22 16:44:30 +01:00

940 lines
28 KiB
JavaScript

/**
* @module YText
*/
import {
YEvent,
AbstractType,
nextID,
createID,
getItemCleanStart,
isVisible,
YTextRefID,
callTypeObservers,
transact,
ContentEmbed,
ContentFormat,
ContentString,
splitSnapshotAffectedStructs,
ID, Doc, Item, Snapshot, Transaction // eslint-disable-line
} from '../internals.js'
import * as decoding from 'lib0/decoding.js' // eslint-disable-line
import * as encoding from 'lib0/encoding.js'
import * as object from 'lib0/object.js'
/**
* @param {any} a
* @param {any} b
* @return {boolean}
*/
const equalAttrs = (a, b) => a === b || (typeof a === 'object' && typeof b === 'object' && a && b && object.equalFlat(a, b))
export class ItemListPosition {
/**
* @param {Item|null} left
* @param {Item|null} right
*/
constructor (left, right) {
this.left = left
this.right = right
}
}
export class ItemTextListPosition extends ItemListPosition {
/**
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} currentAttributes
*/
constructor (left, right, currentAttributes) {
super(left, right)
this.currentAttributes = currentAttributes
}
}
export class ItemInsertionResult extends ItemListPosition {
/**
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} negatedAttributes
*/
constructor (left, right, negatedAttributes) {
super(left, right)
this.negatedAttributes = negatedAttributes
}
}
/**
* @param {Transaction} transaction
* @param {Map<string,any>} currentAttributes
* @param {Item|null} left
* @param {Item|null} right
* @param {number} count
* @return {ItemTextListPosition}
*
* @private
* @function
*/
const findNextPosition = (transaction, currentAttributes, left, right, count) => {
while (right !== null && count > 0) {
switch (right.content.constructor) {
case ContentEmbed:
case ContentString:
if (!right.deleted) {
if (count < right.length) {
// split right
getItemCleanStart(transaction, createID(right.id.client, right.id.clock + count))
}
count -= right.length
}
break
case ContentFormat:
if (!right.deleted) {
updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
}
break
}
left = right
right = right.right
}
return new ItemTextListPosition(left, right, currentAttributes)
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {number} index
* @return {ItemTextListPosition}
*
* @private
* @function
*/
const findPosition = (transaction, parent, index) => {
const currentAttributes = new Map()
const right = parent._start
return findNextPosition(transaction, currentAttributes, null, right, index)
}
/**
* Negate applied formats
*
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} negatedAttributes
* @return {ItemListPosition}
*
* @private
* @function
*/
const insertNegatedAttributes = (transaction, parent, left, right, negatedAttributes) => {
// check if we really need to remove attributes
while (
right !== null && (
right.deleted === true || (
right.content.constructor === ContentFormat &&
equalAttrs(negatedAttributes.get(/** @type {ContentFormat} */ (right.content).key), /** @type {ContentFormat} */ (right.content).value)
)
)
) {
if (!right.deleted) {
negatedAttributes.delete(/** @type {ContentFormat} */ (right.content).key)
}
left = right
right = right.right
}
for (const [key, val] of negatedAttributes) {
left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentFormat(key, val))
left.integrate(transaction)
}
return { left, right }
}
/**
* @param {Map<string,any>} currentAttributes
* @param {ContentFormat} format
*
* @private
* @function
*/
const updateCurrentAttributes = (currentAttributes, format) => {
const { key, value } = format
if (value === null) {
currentAttributes.delete(key)
} else {
currentAttributes.set(key, value)
}
}
/**
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} currentAttributes
* @param {Object<string,any>} attributes
* @return {ItemListPosition}
*
* @private
* @function
*/
const minimizeAttributeChanges = (left, right, currentAttributes, attributes) => {
// go right while attributes[right.key] === right.value (or right is deleted)
while (true) {
if (right === null) {
break
} else if (right.deleted) {
// continue
} else if (right.content.constructor === ContentFormat && equalAttrs(attributes[(/** @type {ContentFormat} */ (right.content)).key] || null, /** @type {ContentFormat} */ (right.content).value)) {
// found a format, update currentAttributes and continue
updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
} else {
break
}
left = right
right = right.right
}
return new ItemListPosition(left, right)
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} currentAttributes
* @param {Object<string,any>} attributes
* @return {ItemInsertionResult}
*
* @private
* @function
**/
const insertAttributes = (transaction, parent, left, right, currentAttributes, attributes) => {
const negatedAttributes = new Map()
// insert format-start items
for (const key in attributes) {
const val = attributes[key]
const currentVal = currentAttributes.get(key) || null
if (!equalAttrs(currentVal, val)) {
// save negated attribute (set null if currentVal undefined)
negatedAttributes.set(key, currentVal)
left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentFormat(key, val))
left.integrate(transaction)
}
}
return new ItemInsertionResult(left, right, negatedAttributes)
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} currentAttributes
* @param {string|object} text
* @param {Object<string,any>} attributes
* @return {ItemListPosition}
*
* @private
* @function
**/
const insertText = (transaction, parent, left, right, currentAttributes, text, attributes) => {
for (const [key] of currentAttributes) {
if (attributes[key] === undefined) {
attributes[key] = null
}
}
const minPos = minimizeAttributeChanges(left, right, currentAttributes, attributes)
const insertPos = insertAttributes(transaction, parent, minPos.left, minPos.right, currentAttributes, attributes)
left = insertPos.left
right = insertPos.right
// insert content
const content = text.constructor === String ? new ContentString(text) : new ContentEmbed(text)
left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, content)
left.integrate(transaction)
return insertNegatedAttributes(transaction, parent, left, insertPos.right, insertPos.negatedAttributes)
}
/**
* @param {Transaction} transaction
* @param {AbstractType<any>} parent
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} currentAttributes
* @param {number} length
* @param {Object<string,any>} attributes
* @return {ItemListPosition}
*
* @private
* @function
*/
const formatText = (transaction, parent, left, right, currentAttributes, length, attributes) => {
const minPos = minimizeAttributeChanges(left, right, currentAttributes, attributes)
const insertPos = insertAttributes(transaction, parent, minPos.left, minPos.right, currentAttributes, attributes)
const negatedAttributes = insertPos.negatedAttributes
left = insertPos.left
right = insertPos.right
// iterate until first non-format or null is found
// delete all formats with attributes[format.key] != null
while (length > 0 && right !== null) {
if (!right.deleted) {
switch (right.content.constructor) {
case ContentFormat: {
const { key, value } = /** @type {ContentFormat} */ (right.content)
const attr = attributes[key]
if (attr !== undefined) {
if (equalAttrs(attr, value)) {
negatedAttributes.delete(key)
} else {
negatedAttributes.set(key, value)
}
right.delete(transaction)
}
updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
break
}
case ContentEmbed:
case ContentString:
if (length < right.length) {
getItemCleanStart(transaction, createID(right.id.client, right.id.clock + length))
}
length -= right.length
break
}
}
left = right
right = right.right
}
// Quill just assumes that the editor starts with a newline and that it always
// ends with a newline. We only insert that newline when a new newline is
// inserted - i.e when length is bigger than type.length
if (length > 0) {
let newlines = ''
for (; length > 0; length--) {
newlines += '\n'
}
left = new Item(nextID(transaction), left, left === null ? null : left.lastId, right, right === null ? null : right.id, parent, null, new ContentString(newlines))
left.integrate(transaction)
}
return insertNegatedAttributes(transaction, parent, left, right, negatedAttributes)
}
/**
* @param {Transaction} transaction
* @param {Item|null} left
* @param {Item|null} right
* @param {Map<string,any>} currentAttributes
* @param {number} length
* @return {ItemListPosition}
*
* @private
* @function
*/
const deleteText = (transaction, left, right, currentAttributes, length) => {
while (length > 0 && right !== null) {
if (right.deleted === false) {
switch (right.content.constructor) {
case ContentFormat:
updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (right.content))
break
case ContentEmbed:
case ContentString:
if (length < right.length) {
getItemCleanStart(transaction, createID(right.id.client, right.id.clock + length))
}
length -= right.length
right.delete(transaction)
break
}
}
left = right
right = right.right
}
return { left, right }
}
/**
* The Quill Delta format represents changes on a text document with
* formatting information. For mor information visit {@link https://quilljs.com/docs/delta/|Quill Delta}
*
* @example
* {
* ops: [
* { insert: 'Gandalf', attributes: { bold: true } },
* { insert: ' the ' },
* { insert: 'Grey', attributes: { color: '#cccccc' } }
* ]
* }
*
*/
/**
* Attributes that can be assigned to a selection of text.
*
* @example
* {
* bold: true,
* font-size: '40px'
* }
*
* @typedef {Object} TextAttributes
*/
/**
* @typedef {Object} DeltaItem
* @property {number|undefined} DeltaItem.delete
* @property {number|undefined} DeltaItem.retain
* @property {string|undefined} DeltaItem.string
* @property {Object<string,any>} DeltaItem.attributes
*/
/**
* Event that describes the changes on a YText type.
*/
export class YTextEvent extends YEvent {
/**
* @param {YText} ytext
* @param {Transaction} transaction
*/
constructor (ytext, transaction) {
super(ytext, transaction)
/**
* @private
* @type {Array<DeltaItem>|null}
*/
this._delta = null
}
/**
* Compute the changes in the delta format.
* A {@link https://quilljs.com/docs/delta/|Quill Delta}) that represents the changes on the document.
*
* @type {Array<DeltaItem>}
*
* @public
*/
get delta () {
if (this._delta === null) {
const y = /** @type {Doc} */ (this.target.doc)
this._delta = []
transact(y, transaction => {
const delta = /** @type {Array<DeltaItem>} */ (this._delta)
const currentAttributes = new Map() // saves all current attributes for insert
const oldAttributes = new Map()
let item = this.target._start
/**
* @type {string?}
*/
let action = null
/**
* @type {Object<string,any>}
*/
const attributes = {} // counts added or removed new attributes for retain
/**
* @type {string|object}
*/
let insert = ''
let retain = 0
let deleteLen = 0
const addOp = () => {
if (action !== null) {
/**
* @type {any}
*/
let op
switch (action) {
case 'delete':
op = { delete: deleteLen }
deleteLen = 0
break
case 'insert':
op = { insert }
if (currentAttributes.size > 0) {
op.attributes = {}
for (const [key, value] of currentAttributes) {
if (value !== null) {
op.attributes[key] = value
}
}
}
insert = ''
break
case 'retain':
op = { retain }
if (Object.keys(attributes).length > 0) {
op.attributes = {}
for (const key in attributes) {
op.attributes[key] = attributes[key]
}
}
retain = 0
break
}
delta.push(op)
action = null
}
}
while (item !== null) {
switch (item.content.constructor) {
case ContentEmbed:
if (this.adds(item)) {
if (!this.deletes(item)) {
addOp()
action = 'insert'
insert = /** @type {ContentEmbed} */ (item.content).embed
addOp()
}
} else if (this.deletes(item)) {
if (action !== 'delete') {
addOp()
action = 'delete'
}
deleteLen += 1
} else if (!item.deleted) {
if (action !== 'retain') {
addOp()
action = 'retain'
}
retain += 1
}
break
case ContentString:
if (this.adds(item)) {
if (!this.deletes(item)) {
if (action !== 'insert') {
addOp()
action = 'insert'
}
insert += /** @type {ContentString} */ (item.content).str
}
} else if (this.deletes(item)) {
if (action !== 'delete') {
addOp()
action = 'delete'
}
deleteLen += item.length
} else if (!item.deleted) {
if (action !== 'retain') {
addOp()
action = 'retain'
}
retain += item.length
}
break
case ContentFormat: {
const { key, value } = /** @type {ContentFormat} */ (item.content)
if (this.adds(item)) {
if (!this.deletes(item)) {
const curVal = currentAttributes.get(key) || null
if (!equalAttrs(curVal, value)) {
if (action === 'retain') {
addOp()
}
if (equalAttrs(value, (oldAttributes.get(key) || null))) {
delete attributes[key]
} else {
attributes[key] = value
}
} else {
item.delete(transaction)
}
}
} else if (this.deletes(item)) {
oldAttributes.set(key, value)
const curVal = currentAttributes.get(key) || null
if (!equalAttrs(curVal, value)) {
if (action === 'retain') {
addOp()
}
attributes[key] = curVal
}
} else if (!item.deleted) {
oldAttributes.set(key, value)
const attr = attributes[key]
if (attr !== undefined) {
if (!equalAttrs(attr, value)) {
if (action === 'retain') {
addOp()
}
if (value === null) {
attributes[key] = value
} else {
delete attributes[key]
}
} else {
item.delete(transaction)
}
}
}
if (!item.deleted) {
if (action === 'insert') {
addOp()
}
updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (item.content))
}
break
}
}
item = item.right
}
addOp()
while (delta.length > 0) {
const lastOp = delta[delta.length - 1]
if (lastOp.retain !== undefined && lastOp.attributes === undefined) {
// retain delta's if they don't assign attributes
delta.pop()
} else {
break
}
}
})
}
return this._delta
}
}
/**
* Type that represents text with formatting information.
*
* This type replaces y-richtext as this implementation is able to handle
* block formats (format information on a paragraph), embeds (complex elements
* like pictures and videos), and text formats (**bold**, *italic*).
*
* @extends AbstractType<YTextEvent>
*/
export class YText extends AbstractType {
/**
* @param {String} [string] The initial value of the YText.
*/
constructor (string) {
super()
/**
* Array of pending operations on this type
* @type {Array<function():void>?}
* @private
*/
this._pending = string !== undefined ? [() => this.insert(0, string)] : []
}
get length () {
return this._length
}
/**
* @param {Doc} y
* @param {Item} item
*
* @private
*/
_integrate (y, item) {
super._integrate(y, item)
try {
/** @type {Array<function>} */ (this._pending).forEach(f => f())
} catch (e) {
console.error(e)
}
this._pending = null
}
_copy () {
return new YText()
}
/**
* Creates YTextEvent and calls observers.
*
* @param {Transaction} transaction
* @param {Set<null|string>} parentSubs Keys changed on this type. `null` if list was modified.
*
* @private
*/
_callObserver (transaction, parentSubs) {
callTypeObservers(this, transaction, new YTextEvent(this, transaction))
}
/**
* Returns the unformatted string representation of this YText type.
*
* @public
*/
toString () {
let str = ''
/**
* @type {Item|null}
*/
let n = this._start
while (n !== null) {
if (!n.deleted && n.countable && n.content.constructor === ContentString) {
str += /** @type {ContentString} */ (n.content).str
}
n = n.right
}
return str
}
/**
* Returns the unformatted string representation of this YText type.
*
* @return {string}
* @public
*/
toJSON () {
return this.toString()
}
/**
* Apply a {@link Delta} on this shared YText type.
*
* @param {any} delta The changes to apply on this element.
*
* @public
*/
applyDelta (delta) {
if (this.doc !== null) {
transact(this.doc, transaction => {
/**
* @type {ItemListPosition}
*/
let pos = new ItemListPosition(null, this._start)
const currentAttributes = new Map()
for (let i = 0; i < delta.length; i++) {
const op = delta[i]
if (op.insert !== undefined) {
// Quill assumes that the content starts with an empty paragraph.
// Yjs/Y.Text assumes that it starts empty. We always hide that
// there is a newline at the end of the content.
// If we omit this step, clients will see a different number of
// paragraphs, but nothing bad will happen.
const ins = (typeof op.insert === 'string' && i === delta.length - 1 && pos.right === null && op.insert.slice(-1) === '\n') ? op.insert.slice(0, -1) : op.insert
if (typeof ins !== 'string' || ins.length > 0) {
pos = insertText(transaction, this, pos.left, pos.right, currentAttributes, ins, op.attributes || {})
}
} else if (op.retain !== undefined) {
pos = formatText(transaction, this, pos.left, pos.right, currentAttributes, op.retain, op.attributes || {})
} else if (op.delete !== undefined) {
pos = deleteText(transaction, pos.left, pos.right, currentAttributes, op.delete)
}
}
})
} else {
/** @type {Array<function>} */ (this._pending).push(() => this.applyDelta(delta))
}
}
/**
* Returns the Delta representation of this YText type.
*
* @param {Snapshot} [snapshot]
* @param {Snapshot} [prevSnapshot]
* @param {function('removed' | 'added', ID):any} [computeYChange]
* @return {any} The Delta representation of this type.
*
* @public
*/
toDelta (snapshot, prevSnapshot, computeYChange) {
/**
* @type{Array<any>}
*/
const ops = []
const currentAttributes = new Map()
const doc = /** @type {Doc} */ (this.doc)
let str = ''
let n = this._start
function packStr () {
if (str.length > 0) {
// pack str with attributes to ops
/**
* @type {Object<string,any>}
*/
const attributes = {}
let addAttributes = false
for (const [key, value] of currentAttributes) {
addAttributes = true
attributes[key] = value
}
/**
* @type {Object<string,any>}
*/
const op = { insert: str }
if (addAttributes) {
op.attributes = attributes
}
ops.push(op)
str = ''
}
}
// snapshots are merged again after the transaction, so we need to keep the
// transalive until we are done
transact(doc, transaction => {
if (snapshot) {
splitSnapshotAffectedStructs(transaction, snapshot)
}
if (prevSnapshot) {
splitSnapshotAffectedStructs(transaction, prevSnapshot)
}
while (n !== null) {
if (isVisible(n, snapshot) || (prevSnapshot !== undefined && isVisible(n, prevSnapshot))) {
switch (n.content.constructor) {
case ContentString: {
const cur = currentAttributes.get('ychange')
if (snapshot !== undefined && !isVisible(n, snapshot)) {
if (cur === undefined || cur.user !== n.id.client || cur.state !== 'removed') {
packStr()
currentAttributes.set('ychange', computeYChange ? computeYChange('removed', n.id) : { type: 'removed' })
}
} else if (prevSnapshot !== undefined && !isVisible(n, prevSnapshot)) {
if (cur === undefined || cur.user !== n.id.client || cur.state !== 'added') {
packStr()
currentAttributes.set('ychange', computeYChange ? computeYChange('added', n.id) : { type: 'added' })
}
} else if (cur !== undefined) {
packStr()
currentAttributes.delete('ychange')
}
str += /** @type {ContentString} */ (n.content).str
break
}
case ContentEmbed:
packStr()
ops.push({
insert: /** @type {ContentEmbed} */ (n.content).embed
})
break
case ContentFormat:
if (isVisible(n, snapshot)) {
packStr()
updateCurrentAttributes(currentAttributes, /** @type {ContentFormat} */ (n.content))
}
break
}
}
n = n.right
}
packStr()
}, splitSnapshotAffectedStructs)
return ops
}
/**
* Insert text at a given index.
*
* @param {number} index The index at which to start inserting.
* @param {String} text The text to insert at the specified position.
* @param {TextAttributes} [attributes] Optionally define some formatting
* information to apply on the inserted
* Text.
* @public
*/
insert (index, text, attributes) {
if (text.length <= 0) {
return
}
const y = this.doc
if (y !== null) {
transact(y, transaction => {
const { left, right, currentAttributes } = findPosition(transaction, this, index)
if (!attributes) {
attributes = {}
// @ts-ignore
currentAttributes.forEach((v, k) => { attributes[k] = v })
}
insertText(transaction, this, left, right, currentAttributes, text, attributes)
})
} else {
/** @type {Array<function>} */ (this._pending).push(() => this.insert(index, text, attributes))
}
}
/**
* Inserts an embed at a index.
*
* @param {number} index The index to insert the embed at.
* @param {Object} embed The Object that represents the embed.
* @param {TextAttributes} attributes Attribute information to apply on the
* embed
*
* @public
*/
insertEmbed (index, embed, attributes = {}) {
if (embed.constructor !== Object) {
throw new Error('Embed must be an Object')
}
const y = this.doc
if (y !== null) {
transact(y, transaction => {
const { left, right, currentAttributes } = findPosition(transaction, this, index)
insertText(transaction, this, left, right, currentAttributes, embed, attributes)
})
} else {
/** @type {Array<function>} */ (this._pending).push(() => this.insertEmbed(index, embed, attributes))
}
}
/**
* Deletes text starting from an index.
*
* @param {number} index Index at which to start deleting.
* @param {number} length The number of characters to remove. Defaults to 1.
*
* @public
*/
delete (index, length) {
if (length === 0) {
return
}
const y = this.doc
if (y !== null) {
transact(y, transaction => {
const { left, right, currentAttributes } = findPosition(transaction, this, index)
deleteText(transaction, left, right, currentAttributes, length)
})
} else {
/** @type {Array<function>} */ (this._pending).push(() => this.delete(index, length))
}
}
/**
* Assigns properties to a range of text.
*
* @param {number} index The position where to start formatting.
* @param {number} length The amount of characters to assign properties to.
* @param {TextAttributes} attributes Attribute information to apply on the
* text.
*
* @public
*/
format (index, length, attributes) {
const y = this.doc
if (y !== null) {
transact(y, transaction => {
const { left, right, currentAttributes } = findPosition(transaction, this, index)
if (right === null) {
return
}
formatText(transaction, this, left, right, currentAttributes, length, attributes)
})
} else {
/** @type {Array<function>} */ (this._pending).push(() => this.format(index, length, attributes))
}
}
/**
* @param {encoding.Encoder} encoder
*
* @private
*/
_write (encoder) {
encoding.writeVarUint(encoder, YTextRefID)
}
}
/**
* @param {decoding.Decoder} decoder
* @return {YText}
*
* @private
* @function
*/
export const readYText = decoder => new YText()