import { existsSync } from "node:fs";
import { mkdir } from "node:fs/promises";
import { spawn } from "node:child_process";
import path from "node:path";

import { loadConfig } from "./config.js";
import { resolveLocalAiCachePath, resolveLocalAiVenvPath, resolvePythonLaunch, resolveVenvPythonPath } from "./python-runtime.js";

async function run(command: string, args: string[], extraEnv?: NodeJS.ProcessEnv): Promise<void> {
  await new Promise<void>((resolve, reject) => {
    const child = spawn(command, args, {
      stdio: "inherit",
      env: {
        ...process.env,
        ...extraEnv,
      },
    });

    child.on("exit", (code) => {
      if (code === 0) {
        resolve();
        return;
      }
      reject(new Error(`${command} ${args.join(" ")} exited with code ${code ?? "null"}`));
    });
    child.on("error", reject);
  });
}

async function ensurePip(pythonBin: string, env: NodeJS.ProcessEnv): Promise<void> {
  await new Promise<void>((resolve, reject) => {
    const child = spawn(pythonBin, ["-m", "pip", "--version"], {
      stdio: "ignore",
      env,
    });
    child.on("exit", (code) => {
      if (code === 0) {
        resolve();
        return;
      }
      reject(new Error("pip missing"));
    });
    child.on("error", reject);
  }).catch(async () => {
    await run(pythonBin, ["-m", "ensurepip", "--upgrade"], env);
  });
}

async function main(): Promise<void> {
  const config = loadConfig();
  const venvPath = resolveLocalAiVenvPath(config);
  const venvPython = resolveVenvPythonPath(config);
  const cachePath = resolveLocalAiCachePath(config);
  const requirementsPath = path.resolve(process.cwd(), "python", "requirements.txt");
  const baseEnv = {
    HF_HOME: cachePath,
    TRANSFORMERS_CACHE: cachePath,
    PYTHONIOENCODING: "utf-8",
  };

  await mkdir(cachePath, { recursive: true });

  if (!existsSync(venvPython)) {
    const launch = resolvePythonLaunch(config, { preferVenv: false });
    console.log(`기본 Python 확인: ${launch.command} ${launch.args.join(" ")}`.trim());
    console.log(`가상환경 생성: ${venvPath}`);
    await run(launch.command, [...launch.args, "-m", "venv", venvPath], baseEnv);
  }

  await ensurePip(venvPython, {
    ...process.env,
    ...baseEnv,
  });

  console.log("로컬 AI 의존성 설치를 시작합니다.");
  await run(venvPython, ["-m", "pip", "install", "--upgrade", "pip", "setuptools", "wheel"], baseEnv);
  await run(venvPython, ["-m", "pip", "install", "-r", requirementsPath], baseEnv);

  console.log("설치가 끝났습니다.");
  console.log("다음 순서:");
  console.log("1. bun run devices");
  console.log("2. bun run start:local");
}

void main().catch((error) => {
  console.error(error instanceof Error ? error.message : String(error));
  process.exit(1);
});