2022-12-01 13:07:23 +01:00

333 lines
11 KiB
JavaScript

import Branch from "../entities/branch.js";
import NoteShort from "../entities/note_short.js";
import Attribute from "../entities/attribute.js";
import server from "./server.js";
import appContext from "../components/app_context.js";
import NoteComplement from "../entities/note_complement.js";
/**
* Froca (FROntend CAche) keeps a read only cache of note tree structure in frontend's memory.
* - notes are loaded lazily when unknown noteId is requested
* - when note is loaded, all its parent and child branches are loaded as well. For a branch to be used, it's not must be loaded before
* - deleted notes are present in the cache as well, but they don't have any branches. As a result check for deleted branch is done by presence check - if the branch is not there even though the corresponding note has been loaded, we can infer it is deleted.
*
* Note and branch deletions are corner cases and usually not needed.
*
* Backend has a similar cache called Becca
*/
class Froca {
constructor() {
this.initializedPromise = this.loadInitialTree();
}
async loadInitialTree() {
const resp = await server.get('tree');
// clear the cache only directly before adding new content which is important for e.g. switching to protected session
/** @type {Object.<string, NoteShort>} */
this.notes = {};
/** @type {Object.<string, Branch>} */
this.branches = {};
/** @type {Object.<string, Attribute>} */
this.attributes = {};
/** @type {Object.<string, Promise<NoteComplement>>} */
this.noteComplementPromises = {};
this.addResp(resp);
}
async loadSubTree(subTreeNoteId) {
const resp = await server.get('tree?subTreeNoteId=' + subTreeNoteId);
this.addResp(resp);
return this.notes[subTreeNoteId];
}
addResp(resp) {
const noteRows = resp.notes;
const branchRows = resp.branches;
const attributeRows = resp.attributes;
const noteIdsToSort = new Set();
for (const noteRow of noteRows) {
const {noteId} = noteRow;
let note = this.notes[noteId];
if (note) {
note.update(noteRow);
// search note doesn't have child branches in database and all the children are virtual branches
if (note.type !== 'search') {
for (const childNoteId of note.children) {
const childNote = this.notes[childNoteId];
if (childNote) {
childNote.parents = childNote.parents.filter(p => p !== noteId);
delete this.branches[childNote.parentToBranch[noteId]];
delete childNote.parentToBranch[noteId];
}
}
note.children = [];
note.childToBranch = {};
}
// we want to remove all "real" branches (represented in the database) since those will be created
// from branches argument but want to preserve all virtual ones from saved search
note.parents = note.parents.filter(parentNoteId => {
const parentNote = this.notes[parentNoteId];
const branch = this.branches[parentNote.childToBranch[noteId]];
if (!parentNote || !branch) {
return false;
}
if (branch.fromSearchNote) {
return true;
}
parentNote.children = parentNote.children.filter(p => p !== noteId);
delete this.branches[parentNote.childToBranch[noteId]];
delete parentNote.childToBranch[noteId];
return false;
});
}
else {
this.notes[noteId] = new NoteShort(this, noteRow);
}
}
for (const branchRow of branchRows) {
const branch = new Branch(this, branchRow);
this.branches[branch.branchId] = branch;
const childNote = this.notes[branch.noteId];
if (childNote) {
childNote.addParent(branch.parentNoteId, branch.branchId);
}
const parentNote = this.notes[branch.parentNoteId];
if (parentNote) {
parentNote.addChild(branch.noteId, branch.branchId, false);
noteIdsToSort.add(parentNote.noteId);
}
}
for (const attributeRow of attributeRows) {
const {attributeId} = attributeRow;
this.attributes[attributeId] = new Attribute(this, attributeRow);
const note = this.notes[attributeRow.noteId];
if (note && !note.attributes.includes(attributeId)) {
note.attributes.push(attributeId);
}
if (attributeRow.type === 'relation') {
const targetNote = this.notes[attributeRow.value];
if (targetNote) {
if (!targetNote.targetRelations.includes(attributeId)) {
targetNote.targetRelations.push(attributeId);
}
}
}
}
// sort all of them at once, this avoids repeated sorts (#1480)
for (const noteId of noteIdsToSort) {
this.notes[noteId].sortChildren();
}
}
async reloadNotes(noteIds) {
if (noteIds.length === 0) {
return;
}
noteIds = Array.from(new Set(noteIds)); // make noteIds unique
const resp = await server.post('tree/load', { noteIds });
this.addResp(resp);
appContext.triggerEvent('notesReloaded', {noteIds});
}
async loadSearchNote(noteId) {
const note = await this.getNote(noteId);
if (!note || note.type !== 'search') {
return;
}
const {searchResultNoteIds, highlightedTokens} = await server.get('search-note/' + note.noteId);
if (!Array.isArray(searchResultNoteIds)) {
throw new Error(`Search note '${note.noteId}' failed: ${searchResultNoteIds}`);
}
// reset all the virtual branches from old search results
if (note.noteId in froca.notes) {
froca.notes[note.noteId].children = [];
froca.notes[note.noteId].childToBranch = {};
}
const branches = [...note.getParentBranches(), ...note.getChildBranches()];
searchResultNoteIds.forEach((resultNoteId, index) => branches.push({
// branchId should be repeatable since sometimes we reload some notes without rerendering the tree
branchId: "virt-" + note.noteId + '-' + resultNoteId,
noteId: resultNoteId,
parentNoteId: note.noteId,
notePosition: (index + 1) * 10,
fromSearchNote: true
}));
// update this note with standard (parent) branches + virtual (children) branches
this.addResp({
notes: [note],
branches,
attributes: []
});
froca.notes[note.noteId].searchResultsLoaded = true;
froca.notes[note.noteId].highlightedTokens = highlightedTokens;
}
/** @returns {NoteShort[]} */
getNotesFromCache(noteIds, silentNotFoundError = false) {
return noteIds.map(noteId => {
if (!this.notes[noteId] && !silentNotFoundError) {
console.trace(`Can't find note "${noteId}"`);
return null;
}
else {
return this.notes[noteId];
}
}).filter(note => !!note);
}
/** @returns {Promise<NoteShort[]>} */
async getNotes(noteIds, silentNotFoundError = false) {
const missingNoteIds = noteIds.filter(noteId => !this.notes[noteId]);
await this.reloadNotes(missingNoteIds);
return noteIds.map(noteId => {
if (!this.notes[noteId] && !silentNotFoundError) {
console.trace(`Can't find note "${noteId}"`);
return null;
} else {
return this.notes[noteId];
}
}).filter(note => !!note);
}
/** @returns {Promise<boolean>} */
async noteExists(noteId) {
const notes = await this.getNotes([noteId], true);
return notes.length === 1;
}
/** @returns {Promise<NoteShort>} */
async getNote(noteId, silentNotFoundError = false) {
if (noteId === 'none') {
console.trace(`No 'none' note.`);
return null;
}
else if (!noteId) {
console.trace(`Falsy noteId '${noteId}', returning null.`);
return null;
}
return (await this.getNotes([noteId], silentNotFoundError))[0];
}
/** @returns {Note|null} */
getNoteFromCache(noteId) {
if (!noteId) {
throw new Error("Empty noteId");
}
return this.notes[noteId];
}
/** @returns {Branch[]} */
getBranches(branchIds, silentNotFoundError = false) {
return branchIds
.map(branchId => this.getBranch(branchId, silentNotFoundError))
.filter(b => !!b);
}
/** @returns {Branch} */
getBranch(branchId, silentNotFoundError = false) {
if (!(branchId in this.branches)) {
if (!silentNotFoundError) {
logError(`Not existing branch ${branchId}`);
}
}
else {
return this.branches[branchId];
}
}
async getBranchId(parentNoteId, childNoteId) {
if (childNoteId === 'root') {
return 'root';
}
const child = await this.getNote(childNoteId);
if (!child) {
logError(`Could not find branchId for parent=${parentNoteId}, child=${childNoteId} since child does not exist`);
return null;
}
return child.parentToBranch[parentNoteId];
}
/**
* @return {Promise<NoteComplement>}
*/
async getNoteComplement(noteId) {
if (!this.noteComplementPromises[noteId]) {
this.noteComplementPromises[noteId] = server.get('notes/' + noteId)
.then(row => new NoteComplement(row))
.catch(e => console.error(`Cannot get note complement for note '${noteId}'`));
// we don't want to keep large payloads forever in memory so we clean that up quite quickly
// this cache is more meant to share the data between different components within one business transaction (e.g. loading of the note into the tab context and all the components)
// this is also a work around for missing invalidation after change
this.noteComplementPromises[noteId].then(
() => setTimeout(() => this.noteComplementPromises[noteId] = null, 1000)
);
}
return await this.noteComplementPromises[noteId];
}
}
const froca = new Froca();
export default froca;