import { createRequestError } from './request-client.js'
import { normalizeBusinessFileAccess } from './business-file-contract.js'

const lineageTreeError = (message) =>
  createRequestError(message, 'LINEAGE_TREE_RESPONSE_INVALID')

const normalizeLineagePersonId = (value) => {
  if (typeof value === 'string' && /^[1-9]\d*$/.test(value)) return value
  if (typeof value === 'number' && Number.isSafeInteger(value) && value > 0) return String(value)
  throw lineageTreeError('世系树包含无效人物标识')
}

const normalizeLineageText = (value, label, { required = false } = {}) => {
  if (value === undefined || value === null) {
    if (required) throw lineageTreeError(`世系树缺少${label}`)
    return ''
  }
  if (typeof value !== 'string') throw lineageTreeError(`世系树${label}无效`)
  const normalized = value.trim()
  if (required && !normalized) throw lineageTreeError(`世系树缺少${label}`)
  return normalized
}

const lineageDatePart = (value, label) => {
  const normalized = normalizeLineageText(value, label)
  if (!normalized) return ''
  if (!/^\d{4}-\d{2}-\d{2}/.test(normalized)) {
    throw lineageTreeError(`世系树${label}无效`)
  }
  if (normalized.length === 10) return normalized
  const instant = new Date(normalized)
  if (Number.isNaN(instant.getTime())) throw lineageTreeError(`世系树${label}无效`)

  const chinaTime = new Date(instant.getTime() + 8 * 60 * 60 * 1000)
  const year = chinaTime.getUTCFullYear()
  const month = String(chinaTime.getUTCMonth() + 1).padStart(2, '0')
  const day = String(chinaTime.getUTCDate()).padStart(2, '0')
  return `${year}-${month}-${day}`
}

const compactLineageYears = (birthDate, deathDate) => {
  const birthYear = birthDate ? birthDate.slice(0, 4) : ''
  const deathYear = deathDate ? deathDate.slice(0, 4) : ''
  return birthYear || deathYear ? `${birthYear}—${deathYear}` : '生卒待补'
}

export const normalizeLineageTree = (value) => {
  if (!Array.isArray(value)) throw lineageTreeError('世系树响应不是列表')
  const seen = new Set()
  const normalized = []
  const normalizedById = new Map()
  const appendNode = (node, parentId, relationOverride = '', spouseOf = '') => {
    if (!node || typeof node !== 'object' || Array.isArray(node)) {
      throw lineageTreeError('世系树包含无效节点')
    }
    const id = normalizeLineagePersonId(node.personId)
    if (seen.has(id)) throw lineageTreeError('世系树包含重复人物标识')
    seen.add(id)
    if (seen.size > 5000) throw lineageTreeError('世系树节点数量超出客户端上限')
    if (!Number.isSafeInteger(node.generation) || node.generation < 1) {
      throw lineageTreeError('世系树人物世代无效')
    }
    const generationName = normalizeLineageText(node.generationName, '字辈')
    const rankName = normalizeLineageText(node.rankName, '排行名称')
    const relationName = normalizeLineageText(node.relationName, '人物关系')
    const birthDate = lineageDatePart(node.birthDate, '出生日期')
    const deathDate = lineageDatePart(node.deathDate, '逝世日期')
    const normalizedNode = {
      id,
      parentId,
      ...(spouseOf ? { spouseOf } : {}),
      name: normalizeLineageText(node.name, '人物姓名', { required: true }),
      relation:
        relationOverride ||
        rankName ||
        (parentId
          ? (relationName && relationName !== '配偶' ? relationName : '排行待补')
          : relationName || '始祖'),
      rankName,
      generation: node.generation,
      branch: generationName
        ? (generationName.endsWith('字辈') ? generationName : `${generationName}字辈`)
        : '字辈待补',
      years: birthDate || deathDate ? `${birthDate}—${deathDate}` : '生卒待补',
      treeYears: compactLineageYears(birthDate, deathDate),
      avatarFile: normalizeBusinessFileAccess(
        node.avatarFile,
        '世系人物头像',
        'LINEAGE_TREE_RESPONSE_INVALID'
      ),
      sex: normalizeLineageText(node.sex, '性别'),
      personStatus: normalizeLineageText(node.personStatus, '人物状态')
    }
    normalized.push(normalizedNode)
    normalizedById.set(id, normalizedNode)
    return id
  }
  const walk = (node, parentId = null, depth = 0) => {
    if (depth > 64) throw lineageTreeError('世系树深度超出客户端上限')
    if (!node || typeof node !== 'object' || Array.isArray(node)) {
      throw lineageTreeError('世系树包含无效节点')
    }
    const spouses = node.spouses ?? []
    const children = node.children ?? []
    if (!Array.isArray(spouses) || !Array.isArray(children)) {
      throw lineageTreeError('世系树亲属集合无效')
    }
    const id = normalizeLineagePersonId(node.personId)
    const knownSpouseId = spouses
      .map((spouse) => normalizeLineagePersonId(spouse?.personId))
      .find((spouseId) => normalizedById.has(spouseId)) || ''
    if (seen.has(id)) {
      if (knownSpouseId) return id
      throw lineageTreeError('世系树包含重复人物标识')
    }
    const knownSpouse = knownSpouseId ? normalizedById.get(knownSpouseId) : null
    const nodeParentId = knownSpouse ? knownSpouse.parentId : parentId
    const appendedId = appendNode(node, nodeParentId, knownSpouse ? '配偶' : '', knownSpouseId)
    spouses.forEach((spouse) => {
      const spouseId = normalizeLineagePersonId(spouse?.personId)
      if (seen.has(spouseId)) return
      appendNode(spouse, nodeParentId, '配偶', appendedId)
    })
    children.forEach((child) => walk(child, knownSpouseId || appendedId, depth + 1))
  }
  value.forEach((root) => walk(root))
  return normalized
}