import type { DiscardCandidate } from '../api/warehouseServices'

export interface DiscardDocument extends DiscardCandidate {
  sources: DiscardCandidate[]
}

/** 下拉按来源单据和操作仓汇总；原始库存身份保留给选箱与提交。 */
export function groupDiscardDocuments(candidates: DiscardCandidate[]): DiscardDocument[] {
  const groups = new Map<string, DiscardDocument>()
  const identities = new Map<string, DiscardCandidate>()
  for (const candidate of candidates) {
    const available = Number(candidate.availablePackages)
    if (candidate.availablePackages == null || !Number.isFinite(available) || available <= 0) continue
    // 按真实来源身份去重；缺身份的旧接口行仍独立保留，不合并不同库存。
    const identity = candidate.sourceType === 'RETURN_CARTON' ? candidate.returnCartonId : candidate.inventoryPositionId || candidate.orderId
    const sourceKey = identity ? JSON.stringify([candidate.overseasWarehouseId, candidate.sourceType, identity]) : null
    const existing = sourceKey ? identities.get(sourceKey) : undefined
    if (existing) {
      // 同一仓位的分片响应合并 SKU 和箱，重复关联不会丢掉箱内商品。
      existing.skus = [...new Map([...existing.skus, ...candidate.skus].map(sku => [sku.skuCode, sku])).values()]
      const cartons = new Map((existing.cartons || []).map(box => [box.cartonId, box]))
      for (const box of candidate.cartons || []) {
        const old = cartons.get(box.cartonId)
        cartons.set(box.cartonId, old ? { ...old, skus: [...new Map([...old.skus, ...box.skus].map(sku => [sku.skuCode, sku])).values()] } : { ...box })
      }
      existing.cartons = [...cartons.values()]
      existing.availablePackages = Math.max(Number(existing.availablePackages), available)
      continue
    }
    const source = { ...candidate, skus: [...candidate.skus], cartons: candidate.cartons?.map(box => ({ ...box, skus: [...box.skus] })) }
    if (sourceKey) identities.set(sourceKey, source)
    const documentNo = candidate.inboundOrderNo || candidate.inboundCode
    const key = JSON.stringify([candidate.overseasWarehouseId, candidate.sourceType, documentNo || candidate.orderId])
    let document = groups.get(key)
    if (!document) {
      document = { ...candidate, orderId: key, sources: [], availablePackages: 0 }
      groups.set(key, document)
    }
    document.sources.push(source)
  }
  for (const document of groups.values()) {
    const boxes = new Set<string>()
    let untrackedPackages = 0
    for (const source of document.sources) {
      if (source.sourceType === 'RETURN_CARTON' && source.returnCartonId) {
        // 退货候选的 availablePackages 是箱内 SKU 件数，一条退货箱只计一箱。
        boxes.add(`RETURN_CARTON:${source.returnCartonId}`)
      } else if (source.cartonSelectionSupported && source.cartons?.length) {
        for (const box of source.cartons) boxes.add(`${source.sourceType}:${box.cartonId}`)
      } else {
        // Long 序列化可能返回字符串，必须先转数值再汇总，避免拼成 005010097。
        const packages = Number(source.availablePackages)
        untrackedPackages += Number.isFinite(packages) && packages > 0 ? packages : 0
      }
    }
    document.availablePackages = boxes.size + untrackedPackages
    document.cartonSelectionSupported = document.sources.every(source => source.cartonSelectionSupported)
    document.cartonSelectionBlockReason = document.sources.find(source => !source.cartonSelectionSupported)?.cartonSelectionBlockReason
  }
  return [...groups.values()]
}