/**
 * gh.js — GitHub CLI wrapper for VS Code extension
 * All GitHub operations via `gh` CLI for proper auth.
 */
const { execFile } = require('child_process');
const { promisify } = require('util');

const run = promisify(execFile);

async function gh(args, opts = {}) {
  try {
    const { stdout } = await run('gh', args, { timeout: 30000, maxBuffer: 10 * 1024 * 1024, ...opts });
    return stdout.trim();
  } catch (e) {
    throw new Error(e.stderr?.trim() || e.message);
  }
}

async function ghJSON(args, opts) {
  const raw = await gh(args, opts);
  if (!raw) return null;
  return JSON.parse(raw);
}

// ─── Auth ────────────────────────────────────────────────────

async function checkStatus() {
  try {
    const out = await gh(['auth', 'status']);
    const user = out.match(/Logged in to github\.com account (\S+)/)?.[1]
      || out.match(/account (\S+)/)?.[1] || 'unknown';
    return { ok: true, user, raw: out };
  } catch (e) {
    return { ok: false, error: e.message };
  }
}

// ─── Repos ───────────────────────────────────────────────────

async function listRepos({ limit = 30 } = {}) {
  return ghJSON([
    'repo', 'list', '--json',
    'name,owner,description,url,stargazerCount,forkCount,primaryLanguage,updatedAt,isPrivate',
    '--limit', String(limit)
  ]);
}

async function createRepo(name, { description = '', isPrivate = false } = {}) {
  const args = ['repo', 'create', name];
  if (description) args.push('--description', description);
  args.push(isPrivate ? '--private' : '--public');
  return gh(args);
}

// ─── Issues ──────────────────────────────────────────────────

async function listIssues(nwo, { state = 'open', limit = 30 } = {}) {
  return ghJSON([
    'issue', 'list', '-R', nwo, '--json',
    'number,title,author,labels,state,createdAt,updatedAt,comments,url,body',
    '--limit', String(limit), '--state', state
  ]);
}

async function viewIssue(nwo, number) {
  const issue = await ghJSON([
    'issue', 'view', String(number), '-R', nwo, '--json',
    'number,title,author,labels,state,createdAt,updatedAt,body,url,comments'
  ]);
  try {
    const comments = await ghJSON([
      'api', `repos/${nwo}/issues/${number}/comments`,
      '--jq', '[.[] | {id:.id, author:.user.login, body:.body, createdAt:.created_at}]'
    ]);
    issue.commentList = comments || [];
  } catch { issue.commentList = []; }
  return issue;
}

async function commentIssue(nwo, number, body) {
  return gh(['issue', 'comment', String(number), '-R', nwo, '--body', body]);
}

async function closeIssue(nwo, number) {
  return gh(['issue', 'close', String(number), '-R', nwo]);
}

async function reopenIssue(nwo, number) {
  return gh(['issue', 'reopen', String(number), '-R', nwo]);
}

// ─── Pull Requests ───────────────────────────────────────────

async function listPRs(nwo, { state = 'open', limit = 30 } = {}) {
  return ghJSON([
    'pr', 'list', '-R', nwo, '--json',
    'number,title,author,state,createdAt,updatedAt,url,body,headRefName,baseRefName,isDraft,comments',
    '--limit', String(limit), '--state', state
  ]);
}

async function viewPR(nwo, number) {
  const pr = await ghJSON([
    'pr', 'view', String(number), '-R', nwo, '--json',
    'number,title,author,state,createdAt,updatedAt,body,url,headRefName,baseRefName,isDraft,comments,additions,deletions,changedFiles'
  ]);
  try {
    const comments = await ghJSON([
      'api', `repos/${nwo}/issues/${number}/comments`,
      '--jq', '[.[] | {id:.id, author:.user.login, body:.body, createdAt:.created_at}]'
    ]);
    pr.commentList = comments || [];
  } catch { pr.commentList = []; }
  return pr;
}

async function commentPR(nwo, number, body) {
  return gh(['pr', 'comment', String(number), '-R', nwo, '--body', body]);
}

async function mergePR(nwo, number, method = 'merge') {
  return gh(['pr', 'merge', String(number), '-R', nwo, `--${method}`, '--yes']);
}

async function closePR(nwo, number) {
  return gh(['pr', 'close', String(number), '-R', nwo]);
}

// ─── Notifications ───────────────────────────────────────────

async function listNotifications() {
  try {
    const raw = await gh(['api', '/notifications']);
    if (!raw) return [];
    return JSON.parse(raw).map(n => ({
      id: n.id, reason: n.reason, unread: n.unread,
      updatedAt: n.updated_at, title: n.subject?.title,
      type: n.subject?.type, url: n.subject?.url,
      repo: n.repository?.full_name
    }));
  } catch { return []; }
}

async function markNotificationRead(threadId) {
  return gh(['api', '-X', 'PATCH', `/notifications/threads/${threadId}`]);
}

async function markAllRead() {
  return gh(['api', '-X', 'PUT', '/notifications', '-f', `last_read_at=${new Date().toISOString()}`]);
}

// ─── Git Operations ──────────────────────────────────────────

async function gitStatus(dir) {
  const branch = (await run('git', ['branch', '--show-current'], { cwd: dir })).stdout.trim();
  const status = (await run('git', ['status', '--short'], { cwd: dir })).stdout.trim();
  const remotes = (await run('git', ['remote', '-v'], { cwd: dir })).stdout.trim();
  let ahead = 0, behind = 0;
  try {
    const ab = (await run('git', ['rev-list', '--left-right', '--count', `origin/${branch}...HEAD`], { cwd: dir })).stdout.trim();
    const p = ab.split(/\s+/);
    behind = parseInt(p[0]) || 0;
    ahead = parseInt(p[1]) || 0;
  } catch {}
  return { branch, status, remotes, ahead, behind };
}

async function gitPush(dir, { remote = 'origin', branch = '' } = {}) {
  if (!branch) branch = (await run('git', ['branch', '--show-current'], { cwd: dir })).stdout.trim();
  const result = await run('git', ['push', '-u', remote, branch], { cwd: dir, timeout: 60000 });
  return result.stdout || result.stderr || 'Push completed.';
}

async function gitInit(dir) {
  return (await run('git', ['init'], { cwd: dir })).stdout.trim();
}

async function gitAddRemote(dir, name, url) {
  return (await run('git', ['remote', 'add', name, url], { cwd: dir })).stdout.trim();
}

async function gitAddAll(dir) {
  return (await run('git', ['add', '-A'], { cwd: dir })).stdout.trim();
}

async function gitCommit(dir, message) {
  return (await run('git', ['commit', '-m', message], { cwd: dir })).stdout.trim();
}

// ─── README / File Push ──────────────────────────────────────

async function updateRepoFile(nwo, filePath, content, message) {
  // Get current file SHA if exists
  let sha = '';
  try {
    const existing = await ghJSON(['api', `repos/${nwo}/contents/${filePath}`]);
    sha = existing?.sha || '';
  } catch {}

  const base64 = Buffer.from(content).toString('base64');
  const args = ['api', '-X', 'PUT', `repos/${nwo}/contents/${filePath}`,
    '-f', `message=${message}`,
    '-f', `content=${base64}`];
  if (sha) args.push('-f', `sha=${sha}`);
  return gh(args);
}

module.exports = {
  checkStatus, listRepos, createRepo,
  listIssues, viewIssue, commentIssue, closeIssue, reopenIssue,
  listPRs, viewPR, commentPR, mergePR, closePR,
  listNotifications, markNotificationRead, markAllRead,
  gitStatus, gitPush, gitInit, gitAddRemote, gitAddAll, gitCommit,
  updateRepoFile
};