/**
 * acr init — 互動式初始化設定
 * 詢問 CF Account ID、KV namespace、API Token、email，
 * 呼叫 arcrun.dev 取得 API Key，寫入 ~/.arcrun/config.yaml
 */
import { createInterface } from 'node:readline/promises';
import { writeFileSync, existsSync, readFileSync, appendFileSync } from 'node:fs';
import { join } from 'node:path';
import chalk from 'chalk';
import { saveConfig, type ArcrunConfig } from '../lib/config.js';

const ARCRUN_REGISTER_URL = 'https://cypher.arcrun.dev/register';

async function prompt(rl: ReturnType<typeof createInterface>, question: string): Promise<string> {
  const answer = await rl.question(chalk.cyan(`? ${question}: `));
  return answer.trim();
}

export async function cmdInit(options: { local?: boolean; selfHosted?: boolean }): Promise<void> {
  const rl = createInterface({ input: process.stdin, output: process.stdout });

  console.log(chalk.bold('\n  arcrun 初始化設定\n'));

  try {
    if (options.local) {
      await initLocal();
    } else if (options.selfHosted) {
      await initSelfHosted(rl);
    } else {
      await initStandard(rl);
    }
  } finally {
    rl.close();
  }
}

async function initLocal(): Promise<void> {
  console.log(chalk.gray('  Local 模式：不需要 Cloudflare 帳號，workflow 由 arcrun.dev 雲端引擎執行\n'));

  const config: ArcrunConfig = {
    mode: 'local',
  };

  saveConfig(config);
  createHelloYamlIfMissing();

  console.log(chalk.green('\n  ✓ 設定完成 → ~/.arcrun/config.yaml（local 模式）'));
  console.log(chalk.green('  ✓ 建立 hello.yaml 範例 workflow\n'));
  console.log('  你可以立刻開始：');
  console.log(chalk.cyan('    acr validate hello.yaml --offline') + '   # 驗證 workflow 格式');
  console.log(chalk.cyan('    acr run hello') + '                        # 執行 hello workflow\n');
  console.log(chalk.gray('  Local 模式：YAML 留在本機，workflow 由 arcrun.dev 引擎執行。'));
  console.log(chalk.gray('  需要用自己的 CF 帳號存放 credentials？執行 acr init（Standard 模式）。\n'));
}

async function initStandard(rl: ReturnType<typeof createInterface>): Promise<void> {
  console.log(chalk.gray('  Standard 模式：使用 arcrun.dev 的執行引擎，credential 存在你自己的 CF KV\n'));

  const accountId = await prompt(rl, '你的 Cloudflare Account ID');
  const kvNamespaceId = await prompt(rl,
    'USER_KV Namespace ID（先至 CF Dashboard 建立一個 KV 後貼上）'
  );
  const cfApiToken = await prompt(rl,
    'CF API Token（只需 KV Edit 權限，供 acr 讀寫你的 KV）'
  );
  const email = await prompt(rl, 'Email（取得 arcrun.dev API Key）');

  process.stdout.write(chalk.gray('\n  → 向 arcrun.dev 取得 API Key...'));

  let apiKey: string;
  try {
    const res = await fetch(ARCRUN_REGISTER_URL, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ email }),  // CF API Token 永遠不離開本機
    });

    if (!res.ok) {
      const err = await res.text();
      throw new Error(`API Key 取得失敗（${res.status}）：${err}`);
    }

    const data = await res.json() as { api_key: string };
    apiKey = data.api_key;
    console.log(chalk.green(' ✓'));
  } catch (e) {
    console.log(chalk.yellow(' ✗（離線模式，請稍後執行 acr init 重試）'));
    apiKey = '';
  }

  const config: ArcrunConfig = {
    mode: 'standard',
    cloudflare_account_id: accountId,
    user_kv_namespace_id: kvNamespaceId,
    cf_api_token: cfApiToken,
    api_key: apiKey,
  };

  saveConfig(config);

  // 建立空白 credentials.yaml
  createCredentialsYamlIfMissing();

  console.log(chalk.green('\n  ✓ 設定完成 → ~/.arcrun/config.yaml'));
  if (apiKey) {
    console.log(chalk.green(`  ✓ API Key：${apiKey.slice(0, 8)}...（已安全儲存）`));
  }
  console.log(chalk.green('  ✓ 建立 credentials.yaml（已加入 .gitignore）\n'));
  console.log(chalk.gray('  你的 credential 與 workflow 存在你自己的 CF KV，arcrun 不會儲存它們。\n'));
  console.log('  下一步：');
  console.log(chalk.cyan('    acr creds push credentials.yaml') + '  # 上傳加密 credentials');
  console.log(chalk.cyan('    acr push workflow.yaml') + '             # 部署 workflow');
  console.log(chalk.cyan('    acr run <workflow_name>') + '           # 執行 workflow\n');
}

async function initSelfHosted(rl: ReturnType<typeof createInterface>): Promise<void> {
  console.log(chalk.gray('  Self-hosted 模式：自行部署所有 Worker 到你的 Cloudflare 帳號\n'));

  const accountId = await prompt(rl, '你的 Cloudflare Account ID');
  const cypherUrl = await prompt(rl, 'Cypher Executor URL（部署後的 workers.dev URL）');
  const webhooksKvId = await prompt(rl, 'WEBHOOKS KV Namespace ID');
  const credentialsKvId = await prompt(rl, 'CREDENTIALS_KV Namespace ID');
  const wasmBucket = await prompt(rl, 'WASM_BUCKET 名稱');
  const cfApiToken = await prompt(rl, 'CF API Token（KV Edit 權限）');

  const config: ArcrunConfig = {
    mode: 'self-hosted',
    cloudflare_account_id: accountId,
    cypher_executor_url: cypherUrl,
    webhooks_kv_namespace_id: webhooksKvId,
    credentials_kv_namespace_id: credentialsKvId,
    wasm_bucket: wasmBucket,
    cf_api_token: cfApiToken,
    multi_tenant: false,
  };

  saveConfig(config);
  createCredentialsYamlIfMissing();

  console.log(chalk.green('\n  ✓ 設定完成 → ~/.arcrun/config.yaml'));
  console.log(chalk.green('  ✓ 建立 credentials.yaml\n'));
}

function createHelloYamlIfMissing(): void {
  const helloPath = join(process.cwd(), 'hello.yaml');
  if (!existsSync(helloPath)) {
    writeFileSync(helloPath,
      '# arcrun hello world workflow\n' +
      '# 執行：acr run hello\n\n' +
      'name: hello\n' +
      'description: "Hello world — 示範如何讓 AI 處理訊息後傳送通知"\n\n' +
      'flow:\n' +
      '  - "input >> ON_SUCCESS >> ai_reply"\n' +
      '  - "ai_reply >> ON_SUCCESS >> log_output"\n\n' +
      'config:\n' +
      '  ai_reply:\n' +
      '    component: "component://cmp_openai_chat"\n' +
      '    model: "gpt-4o-mini"\n' +
      '    prompt: "請用繁體中文說 Hello World，並解釋 arcrun 是什麼"\n' +
      '  log_output:\n' +
      '    component: "component://cmp_log_stdout"\n',
      'utf8'
    );
  }
}

function createCredentialsYamlIfMissing(): void {
  const credPath = join(process.cwd(), 'credentials.yaml');
  if (!existsSync(credPath)) {
    writeFileSync(credPath,
      '# arcrun credentials — 不要提交至 git！\n' +
      '# 執行 acr creds push 上傳加密後的 credential 到你的 CF KV\n\n' +
      '# gmail_token: "your-google-oauth-token"\n' +
      '# telegram_bot_token: "your-telegram-bot-token"\n' +
      '# google_oauth: "your-google-oauth-token"\n' +
      '# line_token: "your-line-notify-token"\n',
      'utf8'
    );
  }

  // 確保 .gitignore 排除 credentials.yaml
  const gitignorePath = join(process.cwd(), '.gitignore');
  if (existsSync(gitignorePath)) {
    const content = readFileSync(gitignorePath, 'utf8');
    if (!content.includes('credentials.yaml')) {
      appendFileSync(gitignorePath, '\ncredentials.yaml\n');
    }
  }
}