#!/usr/bin/env node

import { execFileSync } from 'node:child_process';
import { createHash } from 'node:crypto';
import { mkdir, readFile, writeFile } from 'node:fs/promises';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import vm from 'node:vm';

const repo = path.resolve(path.dirname(fileURLToPath(import.meta.url)), '..');
const sourcePath = 'scripts/deploy-admin-functions.mjs';
const base = process.argv.find((arg) => arg.startsWith('--base='))?.slice(7);
const commit = process.argv.includes('--commit');
const masterKey = process.env.XIAOSHU_MASTER_KEY || '';
const appId = process.env.XIAOSHU_PARSE_APP_ID || '7pIbDBJmKx_main';
const parseUrl = (process.env.XIAOSHU_PARSE_URL || 'https://server.xiaoshu.pro/parse').replace(/\/$/, '');
const sha = (value) => createHash('sha256').update(value).digest('hex');

if (!base) throw new Error('请指定部署前的源码版本：--base=<commit>');
if (!masterKey) throw new Error('缺少 XIAOSHU_MASTER_KEY');

const previousSource = execFileSync('git', ['show', `${base}:${sourcePath}`], { cwd: repo, encoding: 'utf8', maxBuffer: 10_000_000 });
const nextSource = await readFile(path.join(repo, sourcePath), 'utf8');
const markers = [
  ['function appointmentProjection(', 'async function allAppointmentRows('],
  ['async function liveAppointmentRows(', 'async function cachedLiveAppointmentRows('],
  ['async function cachedLiveAppointmentRows(', 'function payrollDateIso('],
  ['async function professionalScheduleDataLocal(', 'function addBusinessDays('],
  ["if(operation==='ops/schedule/calendar')", "if(operation==='ops/coach-availability/list')"],
];

function section(source, start, end) {
  const from = source.indexOf(start);
  const to = source.indexOf(end, from + start.length);
  if (from < 0 || to < 0) throw new Error(`找不到排课代码段：${start}`);
  return source.slice(from, to);
}

function replaceOnce(source, before, after) {
  const first = source.indexOf(before);
  if (first < 0 || source.indexOf(before, first + before.length) >= 0) throw new Error('线上排课代码与预期不一致，已拒绝覆盖');
  return source.slice(0, first) + after + source.slice(first + before.length);
}

const headers = {
  'X-Parse-Application-Id': appId,
  'X-Parse-Master-Key': masterKey,
  'Content-Type': 'application/json',
};
const functionName = 'xiaoshu.ops.gateway.v3';
const where = encodeURIComponent(JSON.stringify({ name: functionName }));
const queryPath = `/classes/Function?where=${where}&keys=objectId,name,code,updatedAt`;
async function parse(pathname, init = {}) {
  const response = await fetch(parseUrl + pathname, { ...init, headers });
  const body = await response.json();
  if (!response.ok || body.error) throw new Error(`云函数接口失败：HTTP ${response.status} ${String(body.error || '')}`);
  return body;
}

const initial = (await parse(queryPath)).results || [];
if (initial.length !== 1 || typeof initial[0].code !== 'string') throw new Error('未找到唯一的线上运营网关');
const original = initial[0];
let patched = original.code;
for (const [start, end] of markers) {
  const before = section(previousSource, start, end);
  const after = section(nextSource, start, end);
  if (before === after) throw new Error(`本地排课代码段没有变化：${start}`);
  patched = replaceOnce(patched, before, after);
}
const helper = section(nextSource, 'function reconcileScheduleAppointments(', 'async function professionalScheduleDataLocal(');
if (patched.includes('function reconcileScheduleAppointments(')) throw new Error('线上已有排课对账函数，不能重复部署');
patched = replaceOnce(patched, 'async function professionalScheduleDataLocal(', helper + 'async function professionalScheduleDataLocal(');
new vm.Script(patched, { filename: functionName });

const result = { functionName, objectId: original.objectId, before: sha(original.code), after: sha(patched), sourceUpdatedAt: original.updatedAt, changedSections: markers.length + 1 };
if (!commit) {
  console.log(JSON.stringify({ ...result, dryRun: true }, null, 2));
  process.exit(0);
}

const backupDir = path.join(repo, 'dist', 'schedule-deploy-backup');
await mkdir(backupDir, { recursive: true });
const backupPath = path.join(backupDir, `${new Date().toISOString().replace(/[:.]/g, '-')}-${original.objectId}.json`);
await writeFile(backupPath, JSON.stringify({ ...result, code: original.code }, null, 2));
const beforeWrite = (await parse(queryPath)).results?.[0];
if (!beforeWrite || sha(beforeWrite.code || '') !== result.before || beforeWrite.updatedAt !== original.updatedAt) throw new Error('线上网关在部署期间发生变化，已停止写入');

try {
  await parse(`/classes/Function/${original.objectId}`, { method: 'PUT', body: JSON.stringify({ code: patched }) });
  const afterWrite = (await parse(queryPath)).results?.[0];
  if (!afterWrite || sha(afterWrite.code || '') !== result.after) throw new Error('写入后代码校验失败');
  console.log(JSON.stringify({ ...result, deployed: true, backupPath }, null, 2));
} catch (error) {
  const current = (await parse(queryPath).catch(() => ({ results: [] }))).results?.[0];
  if (current && sha(current.code || '') === result.after) {
    await parse(`/classes/Function/${original.objectId}`, { method: 'PUT', body: JSON.stringify({ code: original.code }) });
  }
  throw error;
}