const DRAFT_DELETION_ACTION_PATTERN = /删除|删掉|删了|移除|作废|撤销/
const DRAFT_DELETION_TARGET_PATTERN = (
  /草稿|这个单据|这张单据|当前单据|当前申请|当前报销|刚才保存的草稿|刚才的草稿|上面的单据|最近的单据|申请单|报销单/
)
const NON_DRAFT_DELETE_TARGET_PATTERN = /附件|票据|发票|图片|文件|明细|费用行/
const DELETABLE_DRAFT_STATUS = new Set(['', 'draft', 'pending', '待提交', '草稿'])
const SUBMITTED_OR_FINAL_STATUS = new Set([
  'submitted',
  'approved',
  'completed',
  'paid',
  'archived',
  'deleted',
  'rejected',
  'returned',
  '审批中',
  '已审批',
  '已完成',
  '已付款',
  '已归档',
  '已删除',
  '已驳回',
  '已退回'
])

function normalizeCompactText(value = '') {
  return String(value || '').replace(/\s+/g, '').trim()
}

function normalizeDraftDocumentType(payload = {}, claimNo = '') {
  const rawType = String(payload.document_type || payload.documentType || payload.draft_type || payload.draftType || '').trim()
  if (/application|expense_application|申请/.test(rawType)) {
    return 'application'
  }
  if (/reimbursement|expense|报销/.test(rawType)) {
    return 'reimbursement'
  }
  return /^A/i.test(String(claimNo || '').trim()) ? 'application' : 'reimbursement'
}

function normalizeDraftPayload(payload = null, sourceText = '') {
  if (!payload || typeof payload !== 'object') {
    return null
  }
  const claimId = String(payload.claim_id || payload.claimId || payload.id || '').trim()
  const claimNo = String(payload.claim_no || payload.claimNo || payload.document_no || payload.documentNo || '').trim()
  if (!claimId && !claimNo) {
    return null
  }
  const status = String(payload.status || payload.status_label || payload.statusLabel || '').trim()
  if (SUBMITTED_OR_FINAL_STATUS.has(status.toLowerCase()) || SUBMITTED_OR_FINAL_STATUS.has(status)) {
    return null
  }
  if (!DELETABLE_DRAFT_STATUS.has(status.toLowerCase()) && !DELETABLE_DRAFT_STATUS.has(status) && !/草稿/.test(sourceText)) {
    return null
  }
  return {
    claimId,
    claimNo,
    status: status || 'draft',
    documentType: normalizeDraftDocumentType(payload, claimNo)
  }
}

function extractDraftPayloadFromSuggestedActions(message = {}) {
  const actions = Array.isArray(message?.suggestedActions) ? message.suggestedActions : []
  for (const action of [...actions].reverse()) {
    const actionType = String(action?.action_type || action?.actionType || '').trim()
    if (actionType !== 'open_application_detail') {
      continue
    }
    const payload = normalizeDraftPayload(action.payload, String(message.content || message.text || ''))
    if (payload) {
      return payload
    }
  }
  return null
}

export function isWorkbenchDraftDeletionIntent(prompt = '') {
  const compact = normalizeCompactText(prompt)
  if (!compact || !DRAFT_DELETION_ACTION_PATTERN.test(compact)) {
    return false
  }
  if (NON_DRAFT_DELETE_TARGET_PATTERN.test(compact) && !/草稿|单据|申请单|报销单/.test(compact)) {
    return false
  }
  return DRAFT_DELETION_TARGET_PATTERN.test(compact)
}

export function resolveLatestWorkbenchDraftPayload(messages = []) {
  const safeMessages = Array.isArray(messages) ? messages : []
  for (const message of [...safeMessages].reverse()) {
    const sourceText = String(message?.content || message?.text || '')
    const actionPayload = extractDraftPayloadFromSuggestedActions(message)
    if (actionPayload) {
      return actionPayload
    }
    const draftPayload = normalizeDraftPayload(message?.draftPayload, sourceText)
    if (draftPayload) {
      return draftPayload
    }
  }
  return null
}

export function buildWorkbenchDraftDeletionGuidance(draftPayload = {}) {
  const claimNo = String(draftPayload.claimNo || draftPayload.claim_no || '').trim()
  const claimId = String(draftPayload.claimId || draftPayload.claim_id || '').trim()
  const documentType = String(draftPayload.documentType || draftPayload.document_type || 'reimbursement').trim()
  const reference = claimNo || claimId || '最近这张草稿'
  return {
    content: [
      '### 已识别到您想删除草稿',
      `我找到了最近这张草稿：**${reference}**。`,
      '删除草稿会影响单据和附件关联，我不会直接替您删除。请先打开详情页，在详情页点击 **删除草稿** 并完成二次确认。'
    ].join('\n\n'),
    suggestedActions: [{
      label: claimNo ? `查看草稿 ${claimNo}` : '查看草稿详情',
      description: '打开详情页后可点击删除草稿并二次确认。',
      icon: 'mdi mdi-open-in-new',
      action_type: 'open_application_detail',
      payload: {
        claim_id: claimId,
        claim_no: claimNo,
        document_type: documentType
      }
    }]
  }
}