// routes/inventoryStatusReport.js
// Mirrors SAP B1's own "Inventory Status" report (Inventory → Inventory
// Reports → Inventory Status): per-item In Stock / Committed / Ordered /
// Available, aggregated across whichever warehouses the user selects,
// filterable by Item Code range, Preferred Vendor range, and Item Group.
'use strict';
const express = require('express');
const router = express.Router();
const { verifyToken } = require('../middleware/auth');
const { getPool } = require('../services/sqlPool');

const cq = (req) => req.query?.company || req.body?.company || null;

// Available = In Stock − Committed + Ordered — same formula SAP's own
// Inventory Status report uses (verified live against a real item: In Stock
// 2,817.648 − Committed 103,891.201 + Ordered 3,900 = Available −97,173.553,
// matching SAP's screen exactly).
router.get('/', verifyToken, async (req, res) => {
  try {
    const co = cq(req);
    const pool = await getPool(co);
    const sqlEsc = (v) => String(v).replace(/'/g, "''");

    const itemFrom = (req.query.itemFrom || '').trim();
    const itemTo = (req.query.itemTo || '').trim();
    const vendorFrom = (req.query.vendorFrom || '').trim();
    const vendorTo = (req.query.vendorTo || '').trim();
    const itemGroup = (req.query.itemGroup || '').trim();
    const hideZeroStock = req.query.hideZeroStock === '1';
    const warehouses = (req.query.warehouses || '').split(',').map((w) => w.trim()).filter(Boolean);

    const where = [];
    if (itemFrom) where.push(`T0."ItemCode" >= '${sqlEsc(itemFrom)}'`);
    if (itemTo) where.push(`T0."ItemCode" <= '${sqlEsc(itemTo)}'`);
    if (vendorFrom) where.push(`T0."CardCode" >= '${sqlEsc(vendorFrom)}'`);
    if (vendorTo) where.push(`T0."CardCode" <= '${sqlEsc(vendorTo)}'`);
    if (itemGroup) where.push(`T0."ItmsGrpCod" = ${parseInt(itemGroup)}`);

    // No warehouses selected = every warehouse (matches leaving every
    // checkbox unticked on SAP's own selection screen). Otherwise scope the
    // OITW join to just the picked ones, in the JOIN condition — not a
    // WHERE clause — so an item with stock in ONLY unselected warehouses
    // still appears (with everything zeroed out), same as SAP's own report.
    const whJoin = warehouses.length
      ? `AND T1."WhsCode" IN (${warehouses.map((w) => `'${sqlEsc(w)}'`).join(',')})`
      : '';

    const havingZero = hideZeroStock ? `HAVING SUM(ISNULL(T1."OnHand",0)) <> 0` : '';

    const query = `
      SELECT T0."ItemCode", T0."ItemName", T0."InvntryUom" AS "Uom",
             SUM(ISNULL(T1."OnHand",0)) AS "InStock",
             SUM(ISNULL(T1."IsCommited",0)) AS "Committed",
             SUM(ISNULL(T1."OnOrder",0)) AS "Ordered"
      FROM [dbo].[OITM] T0
      LEFT JOIN [dbo].[OITW] T1 ON T1."ItemCode" = T0."ItemCode" ${whJoin}
      ${where.length ? `WHERE ${where.join(' AND ')}` : ''}
      GROUP BY T0."ItemCode", T0."ItemName", T0."InvntryUom"
      ${havingZero}
      ORDER BY T0."ItemCode"`;

    const result = await pool.request().query(query);
    const data = result.recordset.map((r) => {
      const inStock = Number(r.InStock) || 0;
      const committed = Number(r.Committed) || 0;
      const ordered = Number(r.Ordered) || 0;
      return {
        itemCode: r.ItemCode,
        itemName: r.ItemName || '',
        inStock, committed, ordered,
        available: inStock - committed + ordered,
        uom: r.Uom || '',
      };
    });
    res.json({ success: true, data });
  } catch (err) {
    res.status(500).json({ success: false, message: err.message });
  }
});

module.exports = router;