import { existsSync, readdirSync } from 'node:fs';
import { homedir } from 'node:os';
import { basename, dirname, join } from 'node:path';
import { onPath } from './lib.js';

/** Runtime probes are deliberately local, non-interactive, and network-free. */
const SPECS = {
  'oh-my-pi': { binary: 'omp', supported: true, root: (home) => join(home, '.omp', 'agent', 'commands') },
  claude: { binary: 'claude', supported: true, root: (home) => join(home, '.claude', 'commands') },
  codex: { binary: 'codex', supported: true, root: (home) => join(home, '.codex', 'prompts') },
  opencode: { binary: 'opencode', supported: true, root: (home) => join(home, '.config', 'opencode', 'command') },
  antigravity: { binary: 'gemini', supported: false },
  kiro: { binary: 'kiro', supported: false },
  copilot: { binary: 'gh', supported: false },
};

const PROBE_VERSION = 1;

/**
 * @param {{name: string, adapters: {name: string, path: string}[]}[]} platforms
 * @returns {object[]}
 */
export function verifyRuntimePlatforms(platforms) {
  return platforms.map((platform) => verifyRuntimePlatform(platform));
}

/**
 * @param {{name: string, adapters: {name: string, path: string}[]}} platform
 * @returns {object}
 */
function verifyRuntimePlatform(platform) {
  const spec = SPECS[platform.name];
  if (!spec || !spec.supported) {
    return {
      name: platform.name,
      status: 'not-supported',
      probe: { command: spec?.binary ?? null, args: [], network: false, interactive: false, version: PROBE_VERSION },
      resolved: spec ? onPath(spec.binary) : null,
      commands: [],
      missing: [],
      failures: [],
      remediation: '此 AI Agent CLI 沒有可供 tea-sdlc 安全呼叫的 command registry probe；請在該 CLI 內手動確認指令。',
    };
  }

  const resolved = onPath(spec.binary);
  const probe = {
    command: 'filesystem-registry',
    args: [spec.binary],
    network: false,
    interactive: false,
    version: PROBE_VERSION,
  };
  if (resolved === null) {
    return unsupportedRuntime(
      platform,
      probe,
      null,
      `找不到 ${spec.binary}，沒有可安全執行的 runtime probe`,
      `請安裝 ${spec.binary} 並把它加入 PATH 後再重跑 tea-sdlc verify`,
    );
  }


  const root = dirname(platform.adapters[0]?.path ?? spec.root(process.env.HOME || homedir()));
  const expected = platform.adapters.map(({ name }) => name);
  const available = new Set(
    existsSync(root)
      ? readdirSync(root, { withFileTypes: true })
          .filter((entry) => entry.isFile() && entry.name.endsWith('.md'))
          .map((entry) => basename(entry.name, '.md'))
      : [],
  );
  const commands = expected.filter((name) => available.has(name));
  const missing = expected.filter((name) => !available.has(name));
  if (missing.length > 0) {
    return failedRuntime(
      platform,
      { ...probe, registry: root },
      resolved,
      `runtime registry 找不到：${missing.join('、')}`,
      `確認 ${root} 是 ${spec.binary} 的 command registry，然後重跑 tea-sdlc install`,
      commands,
      missing,
    );
  }

  return {
    name: platform.name,
    status: 'pass',
    probe: { ...probe, registry: root },
    resolved,
    commands,
    missing,
    failures: [],
    remediation: null,
  };
}

function unsupportedRuntime(platform, probe, resolved, message, remediation) {
  return {
    name: platform.name,
    status: 'not-supported',
    probe,
    resolved,
    commands: [],
    missing: platform.adapters.map(({ name }) => name),
    failures: [],
    remediation: `${message}；${remediation}`,
  };
}

function failedRuntime(platform, probe, resolved, message, remediation, commands = [], missing = platform.adapters.map(({ name }) => name)) {
  const failure = {
    path: probe.registry ?? null,
    病灶: message,
    修復: remediation,
  };
  return {
    name: platform.name,
    status: 'fail',
    probe,
    resolved,
    commands,
    missing,
    failures: [failure],
    remediation,
  };
}

/** @returns {number} */
export function runtimeProbeVersion() {
  return PROBE_VERSION;
}