/*
* SPDX-FileCopyrightText: 2021-2023 The Refinery Authors
*
* SPDX-License-Identifier: EPL-2.0
*/
import type { ChangeDesc, Transaction } from '@codemirror/state';
import { debounce } from 'lodash-es';
import { nanoid } from 'nanoid';
import type EditorStore from '../editor/EditorStore';
import CancelledError from '../utils/CancelledError';
import TimeoutError from '../utils/TimeoutError';
import getLogger from '../utils/getLogger';
import UpdateStateTracker from './UpdateStateTracker';
import type XtextWebSocketClient from './XtextWebSocketClient';
import {
type ContentAssistEntry,
ContentAssistResult,
DocumentStateResult,
FormattingResult,
isConflictResult,
OccurrencesResult,
} from './xtextServiceResults';
const UPDATE_TIMEOUT_MS = 500;
const log = getLogger('xtext.UpdateService');
export interface AbortSignal {
aborted: boolean;
}
export type CancellableResult =
| { cancelled: false; data: T }
| { cancelled: true };
export interface ContentAssistParams {
caretOffset: number;
proposalsLimit: number;
}
export default class UpdateService {
readonly resourceName: string;
private readonly tracker: UpdateStateTracker;
private readonly idleUpdateLater = debounce(
() => this.idleUpdate(),
UPDATE_TIMEOUT_MS,
);
constructor(
private readonly store: EditorStore,
private readonly webSocketClient: XtextWebSocketClient,
) {
this.resourceName = `${nanoid(7)}.problem`;
this.tracker = new UpdateStateTracker(store);
}
get xtextStateId(): string | undefined {
return this.tracker.xtextStateId;
}
computeChangesSinceLastUpdate(): ChangeDesc {
return this.tracker.computeChangesSinceLastUpdate();
}
onReconnect(): void {
this.tracker.invalidateStateId();
this.updateFullTextOrThrow().catch((error) => {
// Let E_TIMEOUT errors propagate, since if the first update times out,
// we can't use the connection.
if (error instanceof CancelledError) {
// Content assist will perform a full-text update anyways.
log.debug('Full text update cancelled');
return;
}
log.error('Unexpected error during initial update', error);
});
}
onTransaction(transaction: Transaction): void {
if (this.tracker.onTransaction(transaction)) {
this.idleUpdateLater();
}
}
get opened(): boolean {
return this.webSocketClient.opened;
}
private idleUpdate(): void {
if (!this.webSocketClient.opened || !this.tracker.needsUpdate) {
return;
}
if (!this.tracker.lockedForUpdate) {
this.updateOrThrow().catch((error) => {
if (error instanceof CancelledError || error instanceof TimeoutError) {
log.debug('Idle update cancelled');
return;
}
log.error('Unexpected error during scheduled update', error);
});
}
this.idleUpdateLater();
}
/**
* Makes sure that the document state on the server reflects recent
* local changes.
*
* Performs either an update with delta text or a full text update if needed.
* If there are not local dirty changes, the promise resolves immediately.
*
* @returns a promise resolving when the update is completed
*/
private async updateOrThrow(): Promise {
if (!this.tracker.needsUpdate) {
return;
}
await this.tracker.runExclusive(() => this.updateExclusive());
}
private async updateExclusive(): Promise {
if (this.xtextStateId === undefined) {
await this.updateFullTextExclusive();
}
const delta = this.tracker.prepareDeltaUpdateExclusive();
if (delta === undefined) {
return;
}
log.trace('Editor delta', delta);
this.store.analysisStarted();
const result = await this.webSocketClient.send({
resource: this.resourceName,
serviceType: 'update',
requiredStateId: this.xtextStateId,
...delta,
});
const parsedDocumentStateResult = DocumentStateResult.safeParse(result);
if (parsedDocumentStateResult.success) {
this.tracker.setStateIdExclusive(parsedDocumentStateResult.data.stateId);
return;
}
if (isConflictResult(result, 'invalidStateId')) {
await this.updateFullTextExclusive();
}
throw parsedDocumentStateResult.error;
}
private updateFullTextOrThrow(): Promise {
return this.tracker.runExclusive(() => this.updateFullTextExclusive());
}
private async updateFullTextExclusive(): Promise {
log.debug('Performing full text update');
this.tracker.prepareFullTextUpdateExclusive();
this.store.analysisStarted();
const result = await this.webSocketClient.send({
resource: this.resourceName,
serviceType: 'update',
fullText: this.store.state.doc.sliceString(0),
});
const { stateId } = DocumentStateResult.parse(result);
this.tracker.setStateIdExclusive(stateId);
}
async fetchContentAssist(
params: ContentAssistParams,
signal: AbortSignal,
): Promise {
if (!this.tracker.hasPendingChanges && this.xtextStateId !== undefined) {
return this.fetchContentAssistFetchOnly(params, this.xtextStateId);
}
try {
return await this.tracker.runExclusive(
() => this.fetchContentAssistExclusive(params, signal),
true,
);
} catch (error) {
if (
(error instanceof CancelledError || error instanceof TimeoutError) &&
signal.aborted
) {
return [];
}
throw error;
}
}
private async fetchContentAssistExclusive(
params: ContentAssistParams,
signal: AbortSignal,
): Promise {
if (this.xtextStateId === undefined) {
await this.updateFullTextExclusive();
if (this.xtextStateId === undefined) {
throw new Error('failed to obtain Xtext state id');
}
}
if (signal.aborted) {
return [];
}
let entries: ContentAssistEntry[] | undefined;
if (this.tracker.needsUpdate) {
entries = await this.fetchContentAssistWithDeltaExclusive(
params,
this.xtextStateId,
);
}
if (entries !== undefined) {
return entries;
}
if (signal.aborted) {
return [];
}
if (this.xtextStateId === undefined) {
throw new Error('failed to obtain Xtext state id');
}
return this.fetchContentAssistFetchOnly(params, this.xtextStateId);
}
private async fetchContentAssistWithDeltaExclusive(
params: ContentAssistParams,
requiredStateId: string,
): Promise {
const delta = this.tracker.prepareDeltaUpdateExclusive();
if (delta === undefined) {
return undefined;
}
log.trace('Editor delta for content assist', delta);
const fetchUpdateResult = await this.webSocketClient.send({
...params,
resource: this.resourceName,
serviceType: 'assist',
requiredStateId,
...delta,
});
const parsedContentAssistResult =
ContentAssistResult.safeParse(fetchUpdateResult);
if (parsedContentAssistResult.success) {
const {
data: { stateId, entries },
} = parsedContentAssistResult;
this.tracker.setStateIdExclusive(stateId);
return entries;
}
if (isConflictResult(fetchUpdateResult, 'invalidStateId')) {
log.warn('Server state invalid during content assist');
await this.updateFullTextExclusive();
return undefined;
}
throw parsedContentAssistResult.error;
}
private async fetchContentAssistFetchOnly(
params: ContentAssistParams,
requiredStateId: string,
): Promise {
// Fallback to fetching without a delta update.
const fetchOnlyResult = await this.webSocketClient.send({
...params,
resource: this.resourceName,
serviceType: 'assist',
requiredStateId,
});
const { stateId, entries: fetchOnlyEntries } =
ContentAssistResult.parse(fetchOnlyResult);
if (stateId !== requiredStateId) {
throw new Error(
`Unexpected state id, expected: ${requiredStateId} got: ${stateId}`,
);
}
return fetchOnlyEntries;
}
formatText(): Promise {
return this.tracker.runExclusive(() => this.formatTextExclusive());
}
private async formatTextExclusive(): Promise {
await this.updateExclusive();
let { from, to } = this.store.state.selection.main;
if (to <= from) {
from = 0;
to = this.store.state.doc.length;
}
log.debug('Formatting from', from, 'to', to);
const result = await this.webSocketClient.send({
resource: this.resourceName,
serviceType: 'format',
selectionStart: from,
selectionEnd: to,
});
const { stateId, formattedText } = FormattingResult.parse(result);
this.tracker.setStateIdExclusive(stateId, {
from,
to,
insert: formattedText,
});
}
async fetchOccurrences(
getCaretOffset: () => CancellableResult,
): Promise> {
try {
await this.updateOrThrow();
} catch (error) {
if (error instanceof CancelledError || error instanceof TimeoutError) {
return { cancelled: true };
}
throw error;
}
const expectedStateId = this.xtextStateId;
if (expectedStateId === undefined || this.tracker.hasPendingChanges) {
// Just give up if another update is in progress.
return { cancelled: true };
}
const caretOffsetResult = getCaretOffset();
if (caretOffsetResult.cancelled) {
return { cancelled: true };
}
const data = await this.webSocketClient.send({
resource: this.resourceName,
serviceType: 'occurrences',
caretOffset: caretOffsetResult.data,
expectedStateId,
});
if (
isConflictResult(data) ||
this.tracker.hasChangesSince(expectedStateId)
) {
return { cancelled: true };
}
const parsedOccurrencesResult = OccurrencesResult.parse(data);
if (parsedOccurrencesResult.stateId !== expectedStateId) {
return { cancelled: true };
}
return { cancelled: false, data: parsedOccurrencesResult };
}
}