export function validateModuleCode(code) {
  const value = String(code ?? '').trim()
  if (!value) return '编码不能为空'
  if (value.length < 2 || value.length > 50) return '编码长度需为 2-50 个字符'
  if (!/^[a-z][a-z0-9_]*$/.test(value)) {
    return '编码须以小写字母开头，且只能包含小写字母、数字和下划线'
  }
  return ''
}

export function getI18nNamespace(key) {
  return String(key || '').split('.', 1)[0] || 'common'
}

export function isValidI18nKey(key) {
  return /^[A-Za-z][A-Za-z0-9_.:-]{1,149}$/.test(String(key || ''))
}

export function buildModuleItemI18nKey(prefix, moduleCode, itemCode) {
  const normalizedModuleCode = String(moduleCode || '').trim()
  const normalizedItemCode = String(itemCode || '').trim()
  return normalizedModuleCode && normalizedItemCode
    ? `${prefix}.${normalizedModuleCode}.${normalizedItemCode}`
    : null
}

export function buildModuleI18nKey(moduleType, moduleCode) {
  const normalizedModuleCode = String(moduleCode || '').trim()
  if (!normalizedModuleCode) return null
  const prefix = moduleType === 'data' || moduleType === 'query' ? 'module' : 'menu'
  return `${prefix}.${normalizedModuleCode}`
}

export function syncModuleItemI18nKeys(rows, prefix, moduleCode, codeField) {
  let changed = false
  for (const row of rows || []) {
    const key = buildModuleItemI18nKey(prefix, moduleCode, row?.[codeField])
    if (row.b_i18n === key) continue
    row.b_i18n = key
    changed = true
  }
  return changed
}

export function groupI18nRows(rows) {
  const groups = {}
  rows.forEach((item) => {
    const key = item.b_key
    groups[key] ||= { key, values: {}, records: {} }
    groups[key].values[item.b_locale] = item.b_value
    groups[key].records[item.b_locale] = item
  })
  return groups
}

// 将同步字段生成的默认翻译条目并入透视行数组：
// - 已存在同 b_key 的行则补全其空语言值（不覆盖用户已填内容）；
// - 否则新增一行；managedId 用于关联字段，使重命名字段时复用同一行（改名而非新增）。
// 返回新的数组，不修改入参。
export function mergeI18nDefaults(rows, entries) {
  const next = [...rows]
  const byKey = new Map(next.map((r) => [String(r.b_key), r]))
  const managedIds = new Set(
    next
      .map((r) => r._managedId)
      .filter(Boolean)
      .map(String),
  )
  for (const e of entries || []) {
    if (!e.key) continue
    const existing = byKey.get(String(e.key))
    if (existing) {
      // 已存在同键行：仅补全空值，保留用户已配置的翻译
      if (existing[e.locale] == null || existing[e.locale] === '') existing[e.locale] = e.value
      continue
    }
    // 同键不存在，但该受管键已由其它行代表时不再新建，避免重复键
    if (e.managedId && managedIds.has(String(e.managedId))) continue
    const row = {
      _id: 'i18n_' + Math.random().toString(36).slice(2, 10),
      b_key: e.key,
      _localeIds: {},
      _managedId: e.managedId ? String(e.managedId) : undefined,
      _syncInjected: e.managedId ? true : undefined,
      [e.locale]: e.value,
    }
    next.push(row)
    byKey.set(String(e.key), row)
    if (e.managedId) managedIds.add(String(e.managedId))
  }
  return next
}

// 合并同 b_key 的重复透视行，保证一个键仅一行。
// 返回新的数组，不修改入参。
export function consolidatePivotRows(rows) {
  const byKey = new Map()
  const merged = []
  for (const row of rows) {
    const key = String(row.b_key || '')
    const hit = byKey.get(key)
    if (hit) {
      for (const [k, v] of Object.entries(row)) {
        if (k === '_id' || k === '_localeIds') continue
        // 仅当目标为空（null/undefined/空串）且来源非空时才补全，保留首个非空值
        if ((hit[k] == null || hit[k] === '') && v != null) hit[k] = v
      }
      Object.assign(hit._localeIds || (hit._localeIds = {}), row._localeIds || {})
      if (row._managedId && !hit._managedId) hit._managedId = row._managedId
      if (row._syncInjected && !hit._syncInjected) hit._syncInjected = row._syncInjected
      if (row._defaultValue != null && hit._defaultValue == null)
        hit._defaultValue = row._defaultValue
      if (row._sortType && !hit._sortType) hit._sortType = row._sortType
    } else {
      byKey.set(key, row)
      merged.push(row)
    }
  }
  return merged
}