implement PermanentUserData storage prototype

src/utils/DeleteSet.js

@@ -8,6 +8,7 @@ import {
   Item, GC, StructStore, Transaction, ID // eslint-disable-line
 } from '../internals.js'
 
+import * as array from 'lib0/array.js'
 import * as math from 'lib0/math.js'
 import * as map from 'lib0/map.js'
 import * as encoding from 'lib0/encoding.js'
@@ -52,14 +53,13 @@ export class DeleteSet {
  *
  * @param {Transaction} transaction
  * @param {DeleteSet} ds
- * @param {StructStore} store
  * @param {function(GC|Item):void} f
  *
  * @function
  */
-export const iterateDeletedStructs = (transaction, ds, store, f) =>
+export const iterateDeletedStructs = (transaction, ds, f) =>
   ds.clients.forEach((deletes, clientid) => {
-    const structs = /** @type {Array<GC|Item>} */ (store.clients.get(clientid))
+    const structs = /** @type {Array<GC|Item>} */ (transaction.doc.store.clients.get(clientid))
     for (let i = 0; i < deletes.length; i++) {
       const del = deletes[i]
       iterateStructs(transaction, structs, del.clock, del.len, f)
@@ -137,22 +137,27 @@ export const sortAndMergeDeleteSet = ds => {
 }
 
 /**
- * @param {DeleteSet} ds1
- * @param {DeleteSet} ds2
+ * @param {Array<DeleteSet>} dss
  * @return {DeleteSet} A fresh DeleteSet
  */
-export const mergeDeleteSets = (ds1, ds2) => {
+export const mergeDeleteSets = dss => {
   const merged = new DeleteSet()
-  // Write all keys from ds1 to merged. If ds2 has the same key, combine the sets.
-  ds1.clients.forEach((dels1, client) =>
-    merged.clients.set(client, dels1.concat(ds2.clients.get(client) || []))
-  )
-  // Write all missing keys from ds2 to merged.
-  ds2.clients.forEach((dels2, client) => {
-    if (!merged.clients.has(client)) {
-      merged.clients.set(client, dels2)
-    }
-  })
+  for (let dssI = 0; dssI < dss.length; dssI++) {
+    dss[dssI].clients.forEach((delsLeft, client) => {
+      if (!merged.clients.has(client)) {
+        // Write all missing keys from current ds and all following.
+        // If merged already contains `client` current ds has already been added.
+        /**
+         * @type {Array<DeleteItem>}
+         */
+        const dels = delsLeft.slice()
+        for (let i = dssI + 1; i < dss.length; i++) {
+          array.appendTo(dels, dss[i].clients.get(client) || [])
+        }
+        merged.clients.set(client, dels)
+      }
+    })
+  }
   sortAndMergeDeleteSet(merged)
   return merged
 }

src/utils/PermanentUserData.js

@@ -0,0 +1,134 @@
+
+import {
+  YArray,
+  YMap,
+  readDeleteSet,
+  writeDeleteSet,
+  createDeleteSet,
+  ID, DeleteSet, YArrayEvent, Transaction, Doc // eslint-disable-line
+} from '../internals.js'
+
+import * as decoding from 'lib0/decoding.js'
+import * as encoding from 'lib0/encoding.js'
+import { mergeDeleteSets, isDeleted } from './DeleteSet.js'
+
+export class PermanentUserData {
+  /**
+   * @param {Doc} doc
+   * @param {string} key
+   */
+  constructor (doc, key = 'users') {
+    const users = doc.getMap(key)
+    /**
+     * @type {Map<string,DeleteSet>}
+     */
+    const dss = new Map()
+    this.yusers = users
+    this.doc = doc
+    /**
+     * Maps from clientid to userDescription
+     *
+     * @type {Map<number,string>}
+     */
+    this.clients = new Map()
+    this.dss = dss
+    /**
+     * @param {YMap<any>} user
+     * @param {string} userDescription
+     */
+    const initUser = (user, userDescription) => {
+      /**
+       * @type {YArray<Uint8Array>}
+       */
+      const ds = user.get('ds')
+      const ids = user.get('ids')
+      const addClientId = /** @param {number} clientid */ clientid => this.clients.set(clientid, userDescription)
+      ds.observe(/** @param {YArrayEvent<any>} event */ event => {
+        event.changes.added.forEach(item => {
+          item.content.getContent().forEach(encodedDs => {
+            if (encodedDs instanceof Uint8Array) {
+              this.dss.set(userDescription, mergeDeleteSets([this.dss.get(userDescription) || createDeleteSet(), readDeleteSet(decoding.createDecoder(encodedDs))]))
+            }
+          })
+        })
+      })
+      this.dss.set(userDescription, mergeDeleteSets(ds.map(encodedDs => readDeleteSet(decoding.createDecoder(encodedDs)))))
+      ids.observe(/** @param {YArrayEvent<any>} event */ event =>
+        event.changes.added.forEach(item => item.content.getContent().forEach(addClientId))
+      )
+      ids.forEach(addClientId)
+    }
+    // observe users
+    users.observe(event => {
+      event.keysChanged.forEach(userDescription =>
+        initUser(users.get(userDescription), userDescription)
+      )
+    })
+    // add intial data
+    users.forEach(initUser)
+  }
+  /**
+   * @param {Doc} doc
+   * @param {number} clientid
+   * @param {string} userDescription
+   */
+  setUserMapping (doc, clientid, userDescription) {
+    const users = this.yusers
+    let user = users.get(userDescription)
+    if (!user) {
+      user = new YMap()
+      user.set('ids', new YArray())
+      user.set('ds', new YArray())
+      users.set(userDescription, user)
+    }
+    user.get('ids').push([clientid])
+    users.observe(event => {
+      const userOverwrite = users.get(userDescription)
+      if (userOverwrite !== user) {
+        // user was overwritten, port all data over to the next user object
+        // @todo Experiment with Y.Sets here
+        user = userOverwrite
+        // @todo iterate over old type
+        this.clients.forEach((_userDescription, clientid) => {
+          if (userDescription === _userDescription) {
+            user.get('ids').push([clientid])
+          }
+        })
+        const encoder = encoding.createEncoder()
+        const ds = this.dss.get(userDescription)
+        if (ds) {
+          writeDeleteSet(encoder, ds)
+          user.get('ds').push([encoding.toUint8Array(encoder)])
+        }
+      }
+    })
+    doc.on('afterTransaction', /** @param {Transaction} transaction */ transaction => {
+      const yds = user.get('ds')
+      const ds = transaction.deleteSet
+      if (transaction.local && ds.clients.size > 0) {
+        const encoder = encoding.createEncoder()
+        writeDeleteSet(encoder, ds)
+        yds.push([encoding.toUint8Array(encoder)])
+      }
+    })
+  }
+  /**
+   * @param {number} clientid
+   * @return {any}
+   */
+  getUserByClientId (clientid) {
+    return this.clients.get(clientid) || null
+  }
+  /**
+   * @param {ID} id
+   * @return {string | null}
+   */
+  getUserByDeletedId (id) {
+    for (const [userDescription, ds] of this.dss) {
+      if (isDeleted(ds, id)) {
+        return userDescription
+      }
+    }
+    return null
+  }
+}

src/utils/Snapshot.js

@@ -131,10 +131,10 @@ export const splitSnapshotAffectedStructs = (transaction, snapshot) => {
   if (!meta.has(snapshot)) {
     snapshot.sv.forEach((clock, client) => {
       if (clock < getState(store, client)) {
-        getItemCleanStart(transaction, store, createID(client, clock))
+        getItemCleanStart(transaction, createID(client, clock))
       }
     })
-    iterateDeletedStructs(transaction, snapshot.ds, store, item => {})
+    iterateDeletedStructs(transaction, snapshot.ds, item => {})
     meta.add(snapshot)
   }
 }

src/utils/StructStore.js

@@ -197,16 +197,15 @@ export const findIndexCleanStart = (transaction, structs, clock) => {
  * Expects that id is actually in store. This function throws or is an infinite loop otherwise.
  *
  * @param {Transaction} transaction
- * @param {StructStore} store
  * @param {ID} id
  * @return {Item}
  *
  * @private
  * @function
  */
-export const getItemCleanStart = (transaction, store, id) => {
-  const structs = /** @type {Array<GC|Item>} */ (store.clients.get(id.client))
-  return /** @type {Item} */ (structs[findIndexCleanStart(transaction, structs, id.clock)])
+export const getItemCleanStart = (transaction, id) => {
+  const structs = /** @type {Array<Item>} */ (transaction.doc.store.clients.get(id.client))
+  return structs[findIndexCleanStart(transaction, structs, id.clock)]
 }
 
 /**

src/utils/Transaction.js

@@ -46,8 +46,9 @@ export class Transaction {
   /**
    * @param {Doc} doc
    * @param {any} origin
+   * @param {boolean} local
    */
-  constructor (doc, origin) {
+  constructor (doc, origin, local) {
     /**
      * The Yjs instance.
      * @type {Doc}
@@ -95,6 +96,11 @@ export class Transaction {
      * @type {Map<any,any>}
      */
     this.meta = new Map()
+    /**
+     * Whether this change originates from this doc.
+     * @type {boolean}
+     */
+    this.local = local
   }
 }
 
@@ -143,17 +149,17 @@ export const addChangedTypeToTransaction = (transaction, type, parentSub) => {
  *
  * @param {Doc} doc
  * @param {function(Transaction):void} f
- * @param {any} [origin]
+ * @param {any} [origin=true]
  *
  * @private
  * @function
  */
-export const transact = (doc, f, origin = null) => {
+export const transact = (doc, f, origin = null, local = true) => {
   const transactionCleanups = doc._transactionCleanups
   let initialCall = false
   if (doc._transaction === null) {
     initialCall = true
-    doc._transaction = new Transaction(doc, origin)
+    doc._transaction = new Transaction(doc, origin, local)
     transactionCleanups.push(doc._transaction)
     doc.emit('beforeTransaction', [doc._transaction, doc])
   }

src/utils/UndoManager.js

@@ -52,7 +52,7 @@ const popStackItem = (undoManager, stack, eventType) => {
       const stackItem = /** @type {StackItem} */ (stack.pop())
       const itemsToRedo = new Set()
       let performedChange = false
-      iterateDeletedStructs(transaction, stackItem.ds, store, struct => {
+      iterateDeletedStructs(transaction, stackItem.ds, struct => {
         if (struct instanceof Item && scope.some(type => isParentOf(type, struct))) {
           itemsToRedo.add(struct)
         }
@@ -70,10 +70,10 @@ const popStackItem = (undoManager, stack, eventType) => {
           if (struct.redone !== null) {
             let { item, diff } = followRedone(store, struct.id)
             if (diff > 0) {
-              item = getItemCleanStart(transaction, store, createID(item.id.client, item.id.clock + diff))
+              item = getItemCleanStart(transaction, createID(item.id.client, item.id.clock + diff))
             }
             if (item.length > stackItem.len) {
-              getItemCleanStart(transaction, store, createID(item.id.client, item.id.clock + stackItem.len))
+              getItemCleanStart(transaction, createID(item.id.client, item.id.clock + stackItem.len))
             }
             struct = item
           }
@@ -168,7 +168,7 @@ export class UndoManager extends Observable {
       if (now - this.lastChange < captureTimeout && stack.length > 0 && !undoing && !redoing) {
         // append change to last stack op
         const lastOp = stack[stack.length - 1]
-        lastOp.ds = mergeDeleteSets(lastOp.ds, transaction.deleteSet)
+        lastOp.ds = mergeDeleteSets([lastOp.ds, transaction.deleteSet])
         lastOp.len = afterState - lastOp.start
       } else {
         // create a new stack op
@@ -178,7 +178,7 @@ export class UndoManager extends Observable {
         this.lastChange = now
       }
       // make sure that deleted structs are not gc'd
-      iterateDeletedStructs(transaction, transaction.deleteSet, transaction.doc.store, /** @param {Item|GC} item */ item => {
+      iterateDeletedStructs(transaction, transaction.deleteSet, /** @param {Item|GC} item */ item => {
         if (item instanceof Item && this.scope.some(type => isParentOf(type, item))) {
           keepItem(item)
         }

src/utils/encoding.js

@@ -26,6 +26,7 @@ import {
   readAndApplyDeleteSet,
   writeDeleteSet,
   createDeleteSetFromStructStore,
+  transact,
   Doc, Transaction, AbstractStruct, StructStore, ID // eslint-disable-line
 } from '../internals.js'
 
@@ -299,10 +300,10 @@ export const readStructs = (decoder, transaction, store) => {
  * @function
  */
 export const readUpdate = (decoder, ydoc, transactionOrigin) =>
-  ydoc.transact(transaction => {
+  transact(ydoc, transaction => {
     readStructs(decoder, transaction, ydoc.store)
     readAndApplyDeleteSet(decoder, transaction, ydoc.store)
-  }, transactionOrigin)
+  }, transactionOrigin, false)
 
 /**
  * Apply a document update created by, for example, `y.on('update', update => ..)` or `update = encodeStateAsUpdate()`.