// CRITICALimport { randomUUID } from "node:crypto";import type { AppContext } from "../../types/context";import { badRequest, notFound, serviceUnavailable } from "../../core/errors";import { fetchInference } from "../../services/inference/inference-client";import { COMPACTION_SYSTEM_PROMPT, COMPACTION_USER_PROMPT } from "./configs"; type MessageRecord = Record<string, unknown>; export interface ChatCompactionOptions {  model?: string;  systemPrompt?: string;  title?: string;  preserveFirst?: boolean;  preserveLast?: boolean;} export interface ChatCompactionResult {  session: Record<string, unknown>;  summary: string;} const getString = (value: unknown): string | undefined =>  typeof value === "string" ? value : undefined; const getNumber = (value: unknown): number | undefined =>  typeof value === "number" && !Number.isNaN(value) ? value : undefined; const formatToolCalls = (toolCalls: unknown[]): string => {  const formatted = toolCalls    .map((call) => {      if (!call || typeof call !== "object") return null;      const record = call as Record<string, unknown>;      const function_ = record["function"] as Record<string, unknown> | undefined;      const name = getString(function_?.["name"]) ?? "tool";      const args = getString(function_?.["arguments"]);      const callLabel = args ? `${name}(${args})` : `${name}()`;      const rawResult = record["result"];      if (rawResult === undefined || rawResult === null) {        return callLabel;      }      let resultText = "";      let isError = false;      if (typeof rawResult === "string") {        resultText = rawResult;      } else if (typeof rawResult === "object") {        const resultRecord = rawResult as Record<string, unknown>;        const content = getString(resultRecord["content"]);        if (content) {          resultText = content;        } else {          try {            resultText = JSON.stringify(rawResult);          } catch {            resultText = String(rawResult);          }        }        isError = resultRecord["isError"] === true;      } else {        resultText = String(rawResult);      }      if (!resultText) {        return callLabel;      }      const errorSuffix = isError ? " (error)" : "";      return `${callLabel} => ${resultText}${errorSuffix}`;    })    .filter((value): value is string => Boolean(value));  return formatted.length > 0 ? `\n\n[Tool calls]: ${formatted.join("; ")}` : "";}; const buildSummaryMessages = (  messages: MessageRecord[]): Array<{ role: string; content: string }> => {  return messages    .map((message) => {      const role = getString(message["role"]) ?? "assistant";      const content = getString(message["content"]) ?? "";      const toolCalls = Array.isArray(message["tool_calls"]) ? message["tool_calls"] : [];      const toolSuffix = toolCalls.length > 0 ? formatToolCalls(toolCalls) : "";      const combined = `${content}${toolSuffix}`.trim();      if (!combined) return null;      return { role, content: combined };    })    .filter((value): value is { role: string; content: string } => Boolean(value));}; const buildSystemPrompt = (systemPrompt?: string): string => {  if (systemPrompt && systemPrompt.trim()) {    return `${COMPACTION_SYSTEM_PROMPT}\n\nOriginal system prompt:\n${systemPrompt.trim()}`;  }  return COMPACTION_SYSTEM_PROMPT;}; const resolveModel = (  options: ChatCompactionOptions,  session: MessageRecord,  fallbackModel?: string): string => {  return options.model || getString(session["model"]) || fallbackModel || "default";}; const requestSummary = async (  context: AppContext,  model: string,  systemPrompt: string,  messages: Array<{ role: string; content: string }>): Promise<string> => {  const response = await fetchInference(context, "/v1/chat/completions", {    method: "POST",    headers: { "Content-Type": "application/json" },    body: JSON.stringify({      model,      messages: [        { role: "system", content: systemPrompt },        ...messages,        { role: "user", content: COMPACTION_USER_PROMPT },      ],      temperature: 0.3,      stream: false,    }),  });   if (!response.ok) {    throw serviceUnavailable(`Compaction summary failed (${response.status})`);  }   const data = (await response.json()) as {    choices?: Array<{ message?: { content?: string } }>;  };  const summary = data.choices?.[0]?.message?.content?.trim() ?? "";  if (!summary) {    throw badRequest("Compaction summary returned empty content");  }  return summary;}; const createSummaryMessage = (summary: string, model?: string): MessageRecord => {  const content = `Context summary (compacted on ${new Date().toLocaleString()}):\n\n${summary}`;  return {    role: "assistant",    content,    model: model ?? null,    parts: [{ type: "text", text: content }],  };}; const pickFirstUserMessage = (messages: MessageRecord[]): MessageRecord | null =>  messages.find((message) => getString(message["role"]) === "user") ?? null; const pickLastMessage = (messages: MessageRecord[]): MessageRecord | null =>  messages.length > 0 ? (messages[messages.length - 1] ?? null) : null; const cloneMessageToSession = (  context: AppContext,  sessionId: string,  message: MessageRecord): void => {  const role = getString(message["role"]) ?? "assistant";  const content = getString(message["content"]) ?? undefined;  const model = getString(message["model"]) ?? undefined;  const toolCalls = Array.isArray(message["tool_calls"]) ? message["tool_calls"] : undefined;  const toolCallId = getString(message["tool_call_id"]) ?? undefined;  const toolName = getString(message["name"]) ?? undefined;  const parts = Array.isArray(message["parts"]) ? message["parts"] : undefined;  const metadata = Object.prototype.hasOwnProperty.call(message, "metadata")    ? message["metadata"]    : undefined;  const promptTokens = getNumber(message["request_prompt_tokens"]);  const toolsTokens = getNumber(message["request_tools_tokens"]);  const totalInputTokens = getNumber(message["request_total_input_tokens"]);  const completionTokens = getNumber(message["request_completion_tokens"]);   context.stores.chatStore.addMessage(    sessionId,    randomUUID(),    role,    content,    model,    toolCalls,    promptTokens,    toolsTokens,    totalInputTokens,    completionTokens,    parts,    metadata,    toolCallId,    toolName  );}; export const compactChatSession = async (  context: AppContext,  sessionId: string,  options: ChatCompactionOptions = {}): Promise<ChatCompactionResult> => {  const session = context.stores.chatStore.getSession(sessionId);  if (!session) {    throw notFound("Session not found");  }   const current = await context.processManager.findInferenceProcess(context.config.inference_port);  if (!current) {    throw serviceUnavailable("No model running");  }   const messages = Array.isArray(session["messages"])    ? (session["messages"] as MessageRecord[])    : [];  if (messages.length === 0) {    throw badRequest("Session has no messages to compact");  }   const summaryMessages = buildSummaryMessages(messages);  if (summaryMessages.length === 0) {    throw badRequest("Session messages are empty");  }   const systemPrompt = buildSystemPrompt(options.systemPrompt);  const model = resolveModel(options, session, current.served_model_name ?? undefined);  const summaryText = await requestSummary(context, model, systemPrompt, summaryMessages);   const firstUser = options.preserveFirst === false ? null : pickFirstUserMessage(messages);  const lastMessage = options.preserveLast === false ? null : pickLastMessage(messages);   const titleBase = getString(session["title"]) ?? "Chat";  const newTitle = options.title ?? `${titleBase} (Compacted)`;  const newSessionId = randomUUID();  const agentState = Object.prototype.hasOwnProperty.call(session, "agent_state")    ? session["agent_state"]    : undefined;  const newSession = context.stores.chatStore.createSession(    newSessionId,    newTitle,    model,    sessionId,    agentState  );   if (firstUser) {    cloneMessageToSession(context, newSessionId, firstUser);  }   const summaryMessage = createSummaryMessage(summaryText, model);  cloneMessageToSession(context, newSessionId, summaryMessage);   if (lastMessage && (!firstUser || lastMessage["id"] !== firstUser["id"])) {    cloneMessageToSession(context, newSessionId, lastMessage);  }   const hydrated = context.stores.chatStore.getSession(newSessionId) ?? newSession;   return {    session: hydrated,    summary: summaryText,  };};