/**
 * SQLite 数据层（§4.1）
 * 表：settings / ignored_packages / logs
 */
import Database from 'better-sqlite3'
import fs from 'node:fs'
import path from 'node:path'
import { fileURLToPath } from 'node:url'

const __dirname = path.dirname(fileURLToPath(import.meta.url))
// 数据目录：环境变量 DATA_DIR 可覆盖（Docker 挂载 manager-data）
const DATA_DIR = process.env.DATA_DIR || path.join(__dirname, 'data')
fs.mkdirSync(DATA_DIR, { recursive: true })

const db = new Database(path.join(DATA_DIR, 'manager.db'))
db.pragma('journal_mode = WAL')

db.exec(`
CREATE TABLE IF NOT EXISTS settings (
  key   TEXT PRIMARY KEY,
  value TEXT
);
CREATE TABLE IF NOT EXISTS ignored_packages (
  pkg_name   TEXT PRIMARY KEY,
  ignored_at DATETIME DEFAULT CURRENT_TIMESTAMP
);
CREATE TABLE IF NOT EXISTS logs (
  id               INTEGER PRIMARY KEY AUTOINCREMENT,
  action           TEXT DEFAULT 'clean',
  pkg_name         TEXT,
  deleted_versions TEXT,
  deleted_count    INTEGER,
  freed_space      TEXT,
  created_at       DATETIME DEFAULT CURRENT_TIMESTAMP
);
CREATE TABLE IF NOT EXISTS pkglist (
  id         INTEGER PRIMARY KEY AUTOINCREMENT,
  pkg_name   TEXT NOT NULL UNIQUE,
  version    TEXT,
  category   TEXT DEFAULT '',
  status     TEXT DEFAULT 'pending',
  auto       INTEGER DEFAULT 0,
  created_at DATETIME
);
`)

// 北京时间（Asia/Shanghai 固定 UTC+8，无夏令时）：SQLite DEFAULT CURRENT_TIMESTAMP 是 UTC，
// 与前端按本地时间展示相差 8 小时，故写入与迁移统一显式使用北京时间墙上时间字符串
// （格式与前端 slice 兼容：YYYY-MM-DD HH:MM:SS，不带时区后缀，避免被二次误解）
const pad2 = n => String(n).padStart(2, '0')
export function nowIso() {
  const d = new Date(Date.now() + 8 * 3600_000)
  return `${d.getUTCFullYear()}-${pad2(d.getUTCMonth() + 1)}-${pad2(d.getUTCDate())} ${pad2(d.getUTCHours())}:${pad2(d.getUTCMinutes())}:${pad2(d.getUTCSeconds())}`
}

function utcToShanghai(iso) {
  try {
    const ts = Date.parse(iso)
    if (!Number.isFinite(ts)) return null
    const d = new Date(ts + 8 * 3600_000)
    return `${d.getUTCFullYear()}-${pad2(d.getUTCMonth() + 1)}-${pad2(d.getUTCDate())} ${pad2(d.getUTCHours())}:${pad2(d.getUTCMinutes())}:${pad2(d.getUTCSeconds())}`
  } catch {
    return null
  }
}

// 旧库迁移：早期 logs 表无 action 列，运行时补齐（忽略/取消忽略等操作依赖该列区分类型）
const logCols = db.prepare('PRAGMA table_info(logs)').all().map(c => c.name)
if (!logCols.includes('action')) {
  db.exec("ALTER TABLE logs ADD COLUMN action TEXT DEFAULT 'clean'")
}

// 旧库迁移 v1：历史日志/忽略记录的时间戳是 UTC，统一转成北京时间；settings 标志位防重复执行
function migrateTimezone() {
  if (getSetting('timezone_migrated_v1')) return
  db.transaction(() => {
    for (const { id, created_at: t } of db.prepare('SELECT id, created_at FROM logs').all()) {
      if (t) {
        const local = utcToShanghai(t)
        if (local) db.prepare('UPDATE logs SET created_at = ? WHERE id = ?').run(local, id)
      }
    }
    for (const { pkg_name: n, ignored_at: t } of db.prepare('SELECT pkg_name, ignored_at FROM ignored_packages').all()) {
      if (t) {
        const local = utcToShanghai(t)
        if (local) db.prepare('UPDATE ignored_packages SET ignored_at = ? WHERE pkg_name = ?').run(local, n)
      }
    }
    setSetting('timezone_migrated_v1', '1')
  })()
}

// —— settings ——
export function getSetting(key, def = null) {
  const row = db.prepare('SELECT value FROM settings WHERE key = ?').get(key)
  return row ? row.value : def
}

export function setSetting(key, value) {
  db.prepare(
    'INSERT INTO settings (key, value) VALUES (?, ?) ON CONFLICT(key) DO UPDATE SET value = excluded.value',
  ).run(key, String(value))
}

// —— ignored ——
export function getIgnored() {
  return db.prepare('SELECT pkg_name FROM ignored_packages ORDER BY ignored_at DESC').all().map(r => r.pkg_name)
}

export function getIgnoredRows() {
  return db.prepare('SELECT pkg_name, ignored_at FROM ignored_packages ORDER BY ignored_at DESC').all()
}

export function isIgnored(pkgName) {
  return !!db.prepare('SELECT 1 FROM ignored_packages WHERE pkg_name = ?').get(pkgName)
}

export function addIgnored(pkgName) {
  db.prepare(
    'INSERT INTO ignored_packages (pkg_name, ignored_at) VALUES (?, ?) ON CONFLICT(pkg_name) DO NOTHING',
  ).run(pkgName, nowIso())
}

export function removeIgnored(pkgName) {
  db.prepare('DELETE FROM ignored_packages WHERE pkg_name = ?').run(pkgName)
}

// —— logs ——
export function addLog({ action = 'clean', pkgName, deletedVersions = null, deletedCount = 0, freedSpace = null }) {
  const info = db.prepare(
    'INSERT INTO logs (action, pkg_name, deleted_versions, deleted_count, freed_space, created_at) VALUES (?, ?, ?, ?, ?, ?)',
  ).run(action, pkgName, deletedVersions, deletedCount, freedSpace, nowIso())
  return info.lastInsertRowid
}

export function getLogs(limit = 50) {
  return db.prepare(
    'SELECT * FROM logs ORDER BY id DESC LIMIT ?',
  ).all(limit)
}

// 模块加载时执行时间迁移（幂等）
migrateTimezone()

export default db