import fs from "node:fs/promises";
import os from "node:os";
import { autocomplete, intro, isCancel, outro, text } from "@clack/prompts";
import chalk from "chalk";

const home = os.homedir();
const configPath = `${home}/.lmc_config.json`;

export interface AppConfig {
  baseURL: string;
  model: string;
}

export async function initConfig(old: AppConfig | null): Promise<AppConfig> {
  console.log();
  intro(chalk.blue("Welcome to LMC. Let's make a new config!"));

  const baseURL = await text({
    message: "What's your base URL:",
    defaultValue: old?.baseURL ?? "http://127.0.0.1:8080/v1",
    placeholder: old?.baseURL ?? "http://127.0.0.1:8080/v1",
  });
  if (isCancel(baseURL)) process.exit(1);

  const models = await getModels(baseURL);
  const initialValue = models.includes(old?.model ?? "")
    ? old?.model
    : models[0];
  const model = await autocomplete({
    message: "Choose a default model:",
    initialValue,
    placeholder: initialValue ?? "Start typing...",
    options: models.map((model) => ({ value: model })),
    validate: (value) =>
      models.includes(typeof value === "string" ? value : "")
        ? undefined
        : `Unable to find model "${value}"`,
  });
  if (!model || isCancel(model)) process.exit(1);

  const config = { baseURL, model } satisfies AppConfig;

  await fs.writeFile(configPath, JSON.stringify(config, null, "  "));

  outro(chalk.green("Configuration saved!"));

  return config;
}

type Models = {
  data: {
    created: number;
    id: string;
    object: "model";
    owned_by: string;
  }[];
};

async function getModels(url: string) {
  const response = await fetch(`${url}/models`);
  const models = (await response.json()) as Models;
  return models.data.map((model) => model.id);
}

export async function loadConfig(
  configFlag: boolean | undefined,
): Promise<AppConfig | null> {
  let config: AppConfig;
  try {
    const text = await fs.readFile(configPath, "utf8");
    config = JSON.parse(text);
  } catch {
    if (configFlag) return null;
    console.error(`Config not found at ${configPath}`);
    return null;
  }

  return config;
}