/**
 * 盤點差異模組（沙盤推演示意）
 */

/** 單一物料的盤點差異 */
export interface StockCountDiff {
  /** 物料識別碼 */
  materialId: string;
  /** 帳面數量 */
  bookQty: number;
  /** 實盤數量 */
  countedQty: number;
}

/**
 * 計算盤點差異數量
 * @param diff - 單一物料的盤點資料
 * @returns 實盤減帳面的差異值
 */
export const diffQty = (diff: StockCountDiff): number => diff.countedQty - diff.bookQty;

/** 盤點差異報表列 */
export interface StockCountReportRow {
  /** 物料識別碼 */
  materialId: string;
  /** 該物料的差異量 */
  diff: number;
}

/**
 * 依盤點資料彙整差異報表
 * @param diffs - 盤點差異清單
 * @returns 逐物料的差異報表列
 */
export const buildReport = (diffs: StockCountDiff[]): StockCountReportRow[] => diffs.map((diff) => ({ materialId: diff.materialId, diff: diffQty(diff) }));