import { spawn, execSync } from "node:child_process";
import { OLLAMA_URL } from "../config.js";
import {
  getActiveChatModel,
  getActiveAutocompleteModel,
} from "../runtime-config.js";
import { log, warn, err } from "../log.js";
import { commandExists, runPassthrough } from "../util.js";

async function ollamaHealthy(): Promise<boolean> {
  try {
    const res = await fetch(`${OLLAMA_URL}/api/tags`);
    return res.ok;
  } catch {
    return false;
  }
}

async function waitForOllama(timeoutSec: number): Promise<boolean> {
  process.stdout.write("  Waiting for Ollama");
  for (let i = 0; i < timeoutSec; i++) {
    if (await ollamaHealthy()) {
      console.log(" ready!");
      return true;
    }
    process.stdout.write(".");
    await new Promise((r) => setTimeout(r, 1000));
  }
  console.log(" timed out.");
  return false;
}

export async function ensureOllama(): Promise<void> {
  if (await ollamaHealthy()) return;

  if (!commandExists("ollama")) {
    log("Ollama not found. Installing via Homebrew...");
    runPassthrough("brew install ollama");
  }

  log("Starting Ollama...");
  const child = spawn("ollama", ["serve"], {
    stdio: "ignore",
    detached: true,
    env: { ...process.env, OLLAMA_HOST: "127.0.0.1" },
  });
  child.unref();

  const ready = await waitForOllama(15);
  if (!ready) {
    err("Ollama failed to start. Run: ollama serve");
  }
}

export function isModelPulled(ollamaTag: string): boolean {
  try {
    const output = execSync("ollama list", { encoding: "utf-8", stdio: ["pipe", "pipe", "pipe"] });
    return output.includes(ollamaTag);
  } catch {
    return false;
  }
}

export async function pullIfNeeded(ollamaTag: string, label: string): Promise<void> {
  if (isModelPulled(ollamaTag)) {
    log(`${label} already pulled: ${ollamaTag}`);
    return;
  }
  log(`Pulling ${label}: ${ollamaTag} (this may take a while)...`);
  runPassthrough(`ollama pull ${ollamaTag}`);
}

export async function startServers(): Promise<void> {
  await ensureOllama();

  const chatModel = getActiveChatModel();
  const autoModel = getActiveAutocompleteModel();

  await pullIfNeeded(chatModel.ollamaTag, `chat model (${chatModel.name})`);
  await pullIfNeeded(autoModel.ollamaTag, `autocomplete model (${autoModel.name})`);

  log("Ollama is running. Models are pulled and ready.");
}

export function stopServers(): void {
  try {
    execSync("pkill -f ollama", { stdio: "ignore" });
    log("Ollama stopped.");
  } catch {
    warn("Ollama not running.");
  }
}