// Harbor for OpenCode: the STOP gate on every tool call, the brief at the start of each session, and a nudge into
// an idle session when new Harbor messages arrive for this agent (one nudge per batch of messages, never while
// stopped). Installed by `harbor install opencode`; the lines between the markers are filled in by the installer.
import { spawn } from "node:child_process";

// >>> harbor settings >>>
const AGENT = "OpenCode";
const PROJECT = null;
const COMMAND = ["py", "-3.12", "-B", "R:/Workspace/Tools/Harbor/run.py"];
const WAKE_IDLE_SESSIONS = true;   // check idle sessions every minute and nudge them when messages arrive
// <<< harbor settings <<<

function harbor(args, payload) {
  return new Promise((resolve) => {
    const argv = [...COMMAND.slice(1), "--as", AGENT, ...(PROJECT ? ["--project", PROJECT] : []), ...args];
    let out = "";
    let err = "";
    let child;
    try {
      child = spawn(COMMAND[0], argv, { windowsHide: true });
    } catch (error) {
      return resolve({ code: 0, out: "", err: String(error) });
    }
    const timer = setTimeout(() => { try { child.kill(); } catch {} }, 20000);
    child.stdout.on("data", (d) => (out += d));
    child.stderr.on("data", (d) => (err += d));
    child.on("error", (error) => { clearTimeout(timer); resolve({ code: 0, out: "", err: String(error) }); });
    child.on("close", (code) => { clearTimeout(timer); resolve({ code: code ?? 0, out, err }); });
    child.stdin.end(JSON.stringify(payload ?? {}));
  });
}

// The Python hook decides what a stopped agent may still run; the plugin only caches "allowed" briefly.

export const HarborPlugin = async ({ client, directory }) => {
  let gate = { at: 0, blocked: false, reason: "" };
  const idleSessions = new Set();
  let checking = false;

  async function nudge(sessionID) {
    const r = await harbor(["hook", "idle", "--host", "opencode"], { cwd: directory });
    let info = {};
    try { info = JSON.parse(r.out || "{}"); } catch {}
    if (!info.prompt) return false;
    idleSessions.delete(sessionID);
    await client.session.promptAsync({ path: { id: sessionID }, body: { parts: [{ type: "text", text: info.prompt }] } });
    return true;
  }

  if (WAKE_IDLE_SESSIONS) {
    setInterval(async () => {
      if (checking || idleSessions.size === 0) return;
      checking = true;
      try {
        const newest = [...idleSessions].pop();
        await nudge(newest);
      } catch {} finally { checking = false; }
    }, 60000);
  }

  return {
    "tool.execute.before": async (input, output) => {
      const tool = input?.tool ?? "";
      const args = output?.args ?? {};
      const now = Date.now();
      const edits = /edit|write|patch|apply|create|replace/i.test(String(tool));
      if (gate.blocked || edits || now - gate.at > 2000 || /harbor/i.test(tool + JSON.stringify(args))) {
        const r = await harbor(["hook", "pre-tool", "--host", "opencode"], { cwd: directory, tool_name: tool, tool_input: args });
        gate = { at: now, blocked: r.code === 2, reason: r.err.trim() };
      }
      if (gate.blocked) throw new Error(gate.reason || "Harbor: STOP in force for this agent. Do not continue work.");
    },
    event: async ({ event }) => {
      try {
        if (event?.type === "session.created") {
          const id = event.properties?.info?.id ?? event.properties?.sessionID;
          if (!id) return;
          const r = await harbor(["hook", "session-start", "--host", "generic"], { cwd: directory });
          const text = r.out.trim();
          if (text) await client.session.prompt({ path: { id }, body: { noReply: true, parts: [{ type: "text", text }] } });
        } else if (event?.type === "session.idle") {
          const id = event.properties?.sessionID;
          if (!id) return;
          idleSessions.delete(id);
          idleSessions.add(id);
          if (!(await nudge(id))) await harbor(["hook", "turn-end", "--host", "opencode"], { cwd: directory });
        } else if (event?.type === "session.status" && event.properties?.status?.type === "busy") {
          idleSessions.delete(event.properties?.sessionID);
        }
      } catch {}
    },
  };
};