feat: add conversation storage (#140)

apps/freya-backend/src/agent/query-agent.ts

@@ -1,21 +1,74 @@
 export interface QueryAgentAsk {
 	message: string
+	conversationId?: string
+	userMessageEntry?: QueryAgentConversationEntryRef
 }
 
-export type QueryAgentEvent =
+export type QueryAgentStreamEvent =
+	| { type: "conversation"; conversationId: string }
 	| { type: "text_delta"; text: string }
 	| { type: "tool_start"; toolName: string }
 	| { type: "tool_end"; toolName: string; ok: boolean }
 	| { type: "done" }
 	| { type: "error"; message: string }
 
+export const QueryAgentEvent = {
+	Compaction: "compaction",
+} as const
+
+export type QueryAgentEvent = (typeof QueryAgentEvent)[keyof typeof QueryAgentEvent]
+
+export interface QueryAgentConversationEntryRef {
+	id: string
+	sequence: number
+}
+
+export interface QueryAgentCompactedEntryRange {
+	startSequence: number
+	endSequence: number
+}
+
+export interface QueryAgentCompactionEvent {
+	type: typeof QueryAgentEvent.Compaction
+	conversationId: string
+	summary: string
+	firstKeptEntryId: string
+	compactedEntryRange: QueryAgentCompactedEntryRange | null
+	tokensBefore: number
+	details?: unknown
+	fromExtension: boolean
+}
+
+export interface QueryAgentEventMap {
+	[QueryAgentEvent.Compaction]: QueryAgentCompactionEvent
+}
+
+export type QueryAgentEventListener<T extends QueryAgentEvent> = (
+	event: QueryAgentEventMap[T],
+) => void | Promise<void>
+
+export type QueryAgentEventListeners = {
+	[T in QueryAgentEvent]: Set<QueryAgentEventListener<T>>
+}
+
+export function createQueryAgentEventListeners(): QueryAgentEventListeners {
+	return {
+		[QueryAgentEvent.Compaction]: new Set(),
+	}
+}
+
 export interface QueryAgent {
-	ask(input: QueryAgentAsk): AsyncIterable<QueryAgentEvent>
+	ask(input: QueryAgentAsk): AsyncIterable<QueryAgentStreamEvent>
+	addEventListener<T extends QueryAgentEvent>(
+		type: T,
+		listener: QueryAgentEventListener<T>,
+	): () => void
 	dispose(): void
 }
 
 export interface QueryAgentResponse {
 	message: string
+	conversationId?: string
 }
 
 export class QueryAgentError extends Error {
@@ -30,9 +83,13 @@ export async function collectQueryAgentResponse(
 	input: QueryAgentAsk,
 ): Promise<QueryAgentResponse> {
 	let message = ""
+	let conversationId: string | undefined
 
 	for await (const event of agent.ask(input)) {
 		switch (event.type) {
+			case "conversation":
+				conversationId = event.conversationId
+				break
 			case "text_delta":
 				message += event.text
 				break
@@ -45,5 +102,5 @@ export async function collectQueryAgentResponse(
 		}
 	}
 
-	return { message }
+	return { message, conversationId }
 }