const EXPENSE_TYPE_LABELS = {
  travel: '差旅费',
  hotel: '住宿费',
  transport: '交通费',
  meal: '业务招待费',
  entertainment: '业务招待费',
  meeting: '会务费',
  office: '办公用品费',
  training: '培训费',
  communication: '通讯费',
  welfare: '福利费',
  other: '其他费用'
}

const SLOT_LABELS = {
  expense_type: '费用场景',
  amount: '申请金额',
  time_range: '业务时间',
  reason: '申请事由',
  attachments: '附件说明',
  customer_name: '客户名称',
  participants: '参与人员'
}

const PRE_APPROVAL_TYPES = new Set(['travel', 'meeting', 'office', 'training'])
const ATTACHMENT_REQUIRED_TYPES = new Set(['meeting', 'training'])

export const APPLICATION_EXAMPLES = [
  '申请下周去北京做客户现场验收，差旅预算18000元',
  '申请上海产品发布会会务费32000元，需要场地和物料',
  '申请部门集中采购办公用品4800元，用于新员工入职'
]

export function buildExpenseApplicationOntologyContext(currentUser = {}) {
  return {
    document_type: 'expense_application',
    application_stage: 'pre_approval',
    conversation_scenario: 'expense',
    entry_source: 'documents_application',
    role_codes: Array.isArray(currentUser.roleCodes) ? currentUser.roleCodes : [],
    is_admin: Boolean(currentUser.isAdmin),
    name: currentUser.name || '',
    role: currentUser.role || '',
    department: currentUser.department || currentUser.departmentName || '',
    department_name: currentUser.department || currentUser.departmentName || '',
    position: currentUser.position || '',
    grade: currentUser.grade || '',
    employee_no: currentUser.employeeNo || currentUser.employee_no || ''
  }
}

export function resolveEntity(ontology, type) {
  const entities = Array.isArray(ontology?.entities) ? ontology.entities : []
  return entities.find((item) => item?.type === type) || null
}

export function resolveConstraint(ontology, field) {
  const constraints = Array.isArray(ontology?.constraints) ? ontology.constraints : []
  return constraints.find((item) => item?.field === field) || null
}

export function resolveExpenseTypeCode(ontology) {
  const entity = resolveEntity(ontology, 'expense_type')
  return String(entity?.normalized_value || entity?.value || 'other').trim() || 'other'
}

export function resolveExpenseTypeLabel(code) {
  return EXPENSE_TYPE_LABELS[String(code || '').trim()] || EXPENSE_TYPE_LABELS.other
}

export function resolveApplicationAmount(ontology) {
  const amountEntity = resolveEntity(ontology, 'amount')
  const amountConstraint = resolveConstraint(ontology, 'amount')
  const rawValue = amountEntity?.normalized_value || amountEntity?.value || amountConstraint?.value || ''
  const numericValue = Number(String(rawValue).replace(/[^\d.]/g, ''))
  return {
    raw: String(rawValue || '').trim(),
    value: Number.isFinite(numericValue) ? numericValue : 0
  }
}

export function resolveTimeRangeText(ontology) {
  const range = ontology?.time_range || {}
  if (range.start_date && range.end_date) {
    return range.start_date === range.end_date
      ? range.start_date
      : `${range.start_date} 至 ${range.end_date}`
  }
  return String(range.raw || '').trim()
}

export function resolveAttachmentPolicy(expenseTypeCode, amount = 0) {
  const code = String(expenseTypeCode || '').trim()
  if (ATTACHMENT_REQUIRED_TYPES.has(code)) {
    return {
      level: 'required',
      label: '必须提交',
      description: code === 'meeting'
        ? '需补充会议通知、议程、参会范围或预算说明。'
        : '需补充培训通知、课程说明、报价或审批依据。'
    }
  }
  if (code === 'office' && amount >= 5000) {
    return {
      level: 'required',
      label: '必须提交',
      description: '办公采购金额较高，需补充采购清单、报价或预算说明。'
    }
  }
  if (code === 'travel') {
    return {
      level: 'optional',
      label: '说明可选',
      description: '可先提交出差目的、时间和预算；行程或邀请材料可作为补充说明。'
    }
  }
  return {
    level: 'none',
    label: '无需附件',
    description: '当前申请事项可先不提交附件，后续报销阶段再按票据要求补充。'
  }
}

export function buildApplicationFieldsFromOntology(ontology, prompt, currentUser = {}) {
  const expenseTypeCode = resolveExpenseTypeCode(ontology)
  const amount = resolveApplicationAmount(ontology)
  const locationEntity = resolveEntity(ontology, 'location')
  const documentTypeEntity = resolveEntity(ontology, 'document_type')
  const workflowStageEntity = resolveEntity(ontology, 'workflow_stage')
  const attachmentPolicy = resolveAttachmentPolicy(expenseTypeCode, amount.value)

  return {
    documentType: documentTypeEntity?.normalized_value || 'expense_application',
    documentTypeLabel: documentTypeEntity?.value || '费用申请',
    workflowStage: workflowStageEntity?.normalized_value || 'pre_approval',
    workflowStageLabel: workflowStageEntity?.value || '前置申请',
    expenseTypeCode,
    expenseTypeLabel: resolveExpenseTypeLabel(expenseTypeCode),
    amount: amount.value,
    amountDisplay: amount.value ? `¥${amount.value.toLocaleString('zh-CN')}` : '待补充',
    timeRange: resolveTimeRangeText(ontology) || '待补充',
    location: locationEntity?.normalized_value || locationEntity?.value || '待补充',
    reason: String(prompt || '').trim() || '待补充',
    applicant: currentUser.name || currentUser.username || '当前用户',
    department: currentUser.department || currentUser.departmentName || '待补充',
    preApprovalRequired: PRE_APPROVAL_TYPES.has(expenseTypeCode),
    attachmentPolicy,
    missingSlots: normalizeMissingSlots(ontology?.missing_slots || [])
  }
}

export function normalizeMissingSlots(slots = []) {
  const normalized = Array.isArray(slots) ? slots : []
  return normalized.map((item) => ({
    key: String(item || '').trim(),
    label: SLOT_LABELS[String(item || '').trim()] || String(item || '').trim()
  })).filter((item) => item.key)
}