arkantu-core-tools

import { type PromptPreprocessorController, type ChatMessage } from "@lmstudio/sdk";
import { pluginConfig as configSchematics } from "./config";
import { SYSTEM_PROMPT_FULL, SYSTEM_PROMPT_LITE } from "./systemPrompt";
import { readFile } from "fs/promises";
import { join } from "path";
import { loadState } from "./state";

let injectedThisSession = false;

export async function promptPreprocessor(
  ctl: PromptPreprocessorController,
  userMessage: ChatMessage
): Promise<string | ChatMessage> {
  const cfg = ctl.getPluginConfig(configSchematics);
  const workspacePath = cfg.get("workspacePath");
  const compact = cfg.get("compactSystemPrompt");

  const history = await ctl.pullHistory();

  // Detect first turn of conversation
  let isFirst = false;
  if (Array.isArray(history)) {
    isFirst = history.length === 0;
  } else if ("messages" in (history as any)) {
    isFirst = (history as any).messages.length === 0;
  } else {
    isFirst = true;
  }

  history.append(userMessage);

  const userText = userMessage.getText();

  if (!isFirst) {
    // Not the first turn: return the message as is
    return userMessage;
  }

  // Reset injection flag for each new conversation
  injectedThisSession = false;

  // Select system prompt based on configuration
  let systemDoc = compact ? SYSTEM_PROMPT_LITE : SYSTEM_PROMPT_FULL;

  // Try loading custom instructions from the workspace
  const state = await loadState(workspacePath);
  const customPaths = [
    join(state.cwd, ".arkantu", "startup.md"),
    join(state.cwd, "instructions", "startup.md"),
    join(workspacePath, ".arkantu", "startup.md"),
  ];
  for (const p of customPaths) {
    try {
      const custom = await readFile(p, "utf-8");
      if (custom.trim()) {
        systemDoc = `${custom}\n\n---\n\n${systemDoc}`;
        ctl.debug(`[arkantu-core] startup.md loaded from: ${p}`);
        break;
      }
    } catch { /* ignore if not exists */ }
  }

  // Try loading persistent memory
  try {
    const memPath = join(state.cwd, "memory.md");
    const mem = await readFile(memPath, "utf-8");
    if (mem.trim()) {
      systemDoc += `\n\n## 🧠 Persistent Memory\n${mem.substring(0, 2000)}`;
    }
  } catch { /* no memory.md found */ }

  injectedThisSession = true;
  return `${systemDoc}\n\n---\n\n${userText}`;
}