'use strict';

/**
 * 每日进销存 —— 流水列取数（业务库原生口径）
 *
 * 业务库 JSReportReplica 能还原的 4 个流水列（其余 8 列缺单据表，保持「—」）：
 *   采购进仓(+):  rpt.jst_purchase × jst_purchaseItem，按 po_date，状态 Confirmed/Finished，取明细 qty
 *                 （明细 inQty 全为 0 未同步，故用 qty）
 *   采购退货(−):  rpt.jst_purchaseout × jst_purchaseoutItem，按 io_date
 *   销售出仓(−):  rpt.jst_Orders × jst_OrderItem，按 send_date，排除 Delete/Cancelled
 *                 （与「库存周转天数」的发货口径一致；与聚水潭进销存导出的出库单口径有偏差，
 *                   因为销售出库单明细数量在业务库未同步，无法精确还原）
 *   销售退货(+):  rpt.jst_returnAndRefundInfo × jst_returnAndRefundItem，按 as_date，
 *                 类型限定 普通退货/拒收退货/换货/维修，取明细 r_qty（实收数量；
 *                 qty 字段大多未同步，不能用）
 *
 * 符号约定与页面一致：流入为正、流出为负（前端负数标红）。
 * 因为还有 8 类单据（调拨/盘点/加工/其它出入库）在业务库无表，
 * 「期末 ≠ 期初 + 流水之和」，差值即缺失单据的影响。
 */

const FLOW_QUERIES = [
  {
    field: 'purchaseIn',
    sign: 1,
    sql: `
      SELECT p.wms_co_id AS wmsCoId,
             SUM(CAST(ISNULL(pi.qty, 0) AS DECIMAL(18, 2))) AS qty
        FROM rpt.jst_purchase p
        JOIN rpt.jst_purchaseItem pi ON pi.po_id = p.po_id
       WHERE p.wms_co_id IN (%WAREHOUSES%)
         AND p.po_date >= @from
         AND ISNULL(p.status, '') IN ('Confirmed', 'Finished')
       GROUP BY p.wms_co_id`,
  },
  {
    field: 'purchaseReturn',
    sign: -1,
    sql: `
      SELECT o.wms_co_id AS wmsCoId,
             SUM(CAST(ISNULL(oi.qty, 0) AS DECIMAL(18, 2))) AS qty
        FROM rpt.jst_purchaseout o
        JOIN rpt.jst_purchaseoutItem oi ON oi.io_id = o.io_id
       WHERE o.wms_co_id IN (%WAREHOUSES%)
         AND o.io_date >= @from
       GROUP BY o.wms_co_id`,
  },
  {
    field: 'salesOut',
    sign: -1,
    sql: `
      SELECT o.wms_co_id AS wmsCoId,
             SUM(CAST(ISNULL(oi.qty, 0) AS DECIMAL(18, 2))) AS qty
        FROM rpt.jst_Orders o
        JOIN rpt.jst_OrderItem oi ON oi.o_id = o.o_id
       WHERE o.wms_co_id IN (%WAREHOUSES%)
         AND o.send_date >= @from
         AND ISNULL(o.status, '') NOT IN ('Delete', 'Cancelled')
       GROUP BY o.wms_co_id`,
  },
  {
    field: 'salesReturn',
    sign: 1,
    sql: `
      SELECT r.wms_co_id AS wmsCoId,
             SUM(CAST(ISNULL(ri.r_qty, 0) AS DECIMAL(18, 2))) AS qty
        FROM rpt.jst_returnAndRefundInfo r
        JOIN rpt.jst_returnAndRefundItem ri ON ri.as_id = r.as_id
       WHERE r.wms_co_id IN (%WAREHOUSES%)
         AND r.as_date >= @from
         AND ISNULL(r.type, '') IN (N'普通退货', N'拒收退货', N'换货', N'维修')
       GROUP BY r.wms_co_id`,
  },
];

/** mssql 不支持数组参数，按位展开成 @p0,@p1... */
function buildInClause(values, prefix) {
  const params = {};
  const clause = values
    .map((v, i) => {
      params[`${prefix}${i}`] = v;
      return `@${prefix}${i}`;
    })
    .join(',');
  return { clause, params };
}

/** 业务库可还原的流水字段（带符号：流入 +1 / 流出 −1） */
const AVAILABLE_FLOW_FIELDS = FLOW_QUERIES.map((q) => q.field);

/**
 * 拉取自 fromText（含）以来各仓的流水合计。
 * @returns {Promise<Map<string, Object>>} key = wmsCoId 字符串，value = { purchaseIn, purchaseReturn, salesOut, salesReturn }（带符号，无记录的字段不出现）
 */
async function fetchFlows(cloudDb, wmsCoIds, fromText) {
  if (!cloudDb || typeof cloudDb.query !== 'function') {
    throw new TypeError('fetchFlows 第一个参数必须是数据库实例（防呆：调用漏传 cloudDb 时立即报错而非静默返回空）');
  }
  const map = new Map();
  if (!wmsCoIds.length || !fromText) return map;
  for (const q of FLOW_QUERIES) {
    const { clause, params } = buildInClause(wmsCoIds, 'w');
    const sqlText = q.sql.replace('%WAREHOUSES%', clause);
    const rows = await cloudDb.query(sqlText, { ...params, from: fromText }, { requestTimeout: 120000 });
    for (const r of rows) {
      const key = String(r.wmsCoId);
      const entry = map.get(key) || {};
      const qty = Number(r.qty) || 0;
      entry[q.field] = q.sign * qty;
      map.set(key, entry);
    }
  }
  return map;
}

module.exports = {
  AVAILABLE_FLOW_FIELDS,
  FLOW_QUERIES,
  fetchFlows,
  buildInClause,
};