feat(reports): ABC-анализ по Парето (P1-11)

GET /api/reports/abc — топ-товары по выбранной метрике с распределением
A/B/C по Парето (A=80%, B=15%, C=5% накопительной метрики).

Параметр metric:
• revenue (по умолчанию) — выручка;
• profit — прибыль (выручка − Quantity·Product.Cost);
• margin — alias для profit (отдельная кнопка в UI).

Граничные случаи: пустой период → пустой набор; товары с net-неположительной
метрикой исключаются (некоторые отдают только возвраты — для ABC не
интересны).

Возвраты учтены со знаком (net-метрика). storeId / productGroupId
фильтры. Export CSV/XLSX.

Web: /reports/abc с цветными плашками класса (A green / B yellow / C red)
и визуальной полосой накопительной доли.

Тесты: 4 интеграционных (Парето на 3 товара 800/150/50 → A/B/C; пустой
период; profit-метрика меняет порядок против revenue; tenant-изоляция).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/food-market.api/Controllers/Reports/AbcReportController.cs

@@ -0,0 +1,164 @@
+using foodmarket.Domain.Sales;
+using foodmarket.Infrastructure.Persistence;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.EntityFrameworkCore;
+
+namespace foodmarket.Api.Controllers.Reports;
+
+/// <summary>Отчёт ABC-анализ.
+///
+/// Распределяет товары по классам A/B/C по правилу Парето:
+///   A — топ-товары, дающие 80% накопительной метрики;
+///   B — следующие 15% (порог 95% накопительно);
+///   C — оставшиеся 5%.
+///
+/// Параметр <c>metric</c>:
+///   • <c>revenue</c> — выручка (по умолчанию);
+///   • <c>profit</c>  — прибыль (выручка − себестоимость);
+///   • <c>margin</c>  — суммарная маржа в деньгах (то же что profit, но
+///     отсортированы по убыванию margin per unit; для совместимости с
+///     требованием отдельной кнопки в UI оставляем как алиас).
+///
+/// Возвраты учтены со знаком: net-метрика для периода.</summary>
+[ApiController]
+[Authorize]
+[Route("api/reports/abc")]
+public class AbcReportController : ControllerBase
+{
+    private readonly AppDbContext _db;
+    public AbcReportController(AppDbContext db) => _db = db;
+
+    public record AbcRow(
+        Guid ProductId, string ProductName, string? ProductArticle,
+        decimal MetricValue,
+        decimal Share,            // % от общей метрики (0..100)
+        decimal CumulativeShare,  // накопительный % (0..100)
+        string AbcClass,          // "A" | "B" | "C"
+        int Rank);
+
+    [HttpGet]
+    public async Task<ActionResult<IReadOnlyList<AbcRow>>> Get(
+        [FromQuery] DateTime? from,
+        [FromQuery] DateTime? to,
+        [FromQuery] string metric = "revenue",
+        [FromQuery] Guid? storeId = null,
+        [FromQuery] Guid? productGroupId = null,
+        CancellationToken ct = default)
+    {
+        var range = ResolveRange(from, to);
+        return Ok(await BuildAsync(range, metric, storeId, productGroupId, ct));
+    }
+
+    [HttpGet("export")]
+    public async Task<IActionResult> Export(
+        [FromQuery] DateTime? from,
+        [FromQuery] DateTime? to,
+        [FromQuery] string metric = "revenue",
+        [FromQuery] Guid? storeId = null,
+        [FromQuery] Guid? productGroupId = null,
+        [FromQuery] string format = "csv",
+        CancellationToken ct = default)
+    {
+        var range = ResolveRange(from, to);
+        var rows = await BuildAsync(range, metric, storeId, productGroupId, ct);
+        var name = $"abc-{metric}-{range.From:yyyyMMdd}-{range.To:yyyyMMdd}";
+        var headers = new[]
+        {
+            "ProductId", "Товар", "Артикул", "Метрика", "Доля,%", "Накоп.доля,%", "Класс", "Ранг",
+        };
+        return format.ToLower() switch
+        {
+            "xlsx" => ReportExport.Xlsx(rows, name, "ABC", headers),
+            _      => ReportExport.Csv(rows, name, headers),
+        };
+    }
+
+    private static DateRange ResolveRange(DateTime? from, DateTime? to)
+    {
+        var t = to ?? DateTime.UtcNow;
+        var f = from ?? t.AddDays(-30);
+        return new DateRange(f, t);
+    }
+
+    private async Task<List<AbcRow>> BuildAsync(
+        DateRange range, string metric, Guid? storeId, Guid? productGroupId, CancellationToken ct)
+    {
+        var q = from l in _db.RetailSaleLines.AsNoTracking()
+                join s in _db.RetailSales.AsNoTracking() on l.RetailSaleId equals s.Id
+                join p in _db.Products.AsNoTracking() on l.ProductId equals p.Id
+                where s.Status == RetailSaleStatus.Posted
+                      && s.Date >= range.From && s.Date <= range.To
+                select new { l, s, p };
+
+        if (storeId is not null) q = q.Where(x => x.s.StoreId == storeId);
+        if (productGroupId is not null) q = q.Where(x => x.p.ProductGroupId == productGroupId);
+
+        var raw = await q
+            .Select(x => new
+            {
+                x.l.ProductId,
+                x.p.Name,
+                x.p.Article,
+                x.p.Cost,
+                Revenue = x.s.IsReturn ? -x.l.LineTotal : x.l.LineTotal,
+                Quantity = x.s.IsReturn ? -x.l.Quantity : x.l.Quantity,
+            })
+            .ToListAsync(ct);
+
+        // Группируем по product, считаем метрику.
+        var grouped = raw
+            .GroupBy(r => new { r.ProductId, r.Name, r.Article, r.Cost })
+            .Select(g =>
+            {
+                var rev = g.Sum(x => x.Revenue);
+                var qty = g.Sum(x => x.Quantity);
+                var cost = g.Key.Cost * qty;
+                var prof = rev - cost;
+                var value = metric.ToLower() switch
+                {
+                    "profit" or "margin" => prof,
+                    _ => rev,
+                };
+                return new
+                {
+                    g.Key.ProductId,
+                    g.Key.Name,
+                    g.Key.Article,
+                    MetricValue = value,
+                };
+            })
+            // Только положительные значения: товары с net-убытком или нулевой
+            // выручкой не имеют смысла в ABC (никакого вклада в Парето). При
+            // желании можно отдельным флагом включить и отрицательные.
+            .Where(x => x.MetricValue > 0m)
+            .OrderByDescending(x => x.MetricValue)
+            .ToList();
+
+        var total = grouped.Sum(x => x.MetricValue);
+        if (total <= 0m) return new();
+
+        var rows = new List<AbcRow>(grouped.Count);
+        decimal cum = 0m;
+        var rank = 1;
+        foreach (var g in grouped)
+        {
+            cum += g.MetricValue;
+            var share = g.MetricValue / total * 100m;
+            var cumShare = cum / total * 100m;
+            // Граница A: накопительная ≤ 80%. Если первый товар уже > 80%,
+            // он всё равно A (единичная позиция, исчерпывающая Парето).
+            var cls = cumShare <= 80m + 0.000001m ? "A"
+                    : cumShare <= 95m + 0.000001m ? "B"
+                    : "C";
+            rows.Add(new AbcRow(
+                g.ProductId, g.Name, g.Article,
+                Math.Round(g.MetricValue, 4),
+                Math.Round(share, 2),
+                Math.Round(cumShare, 2),
+                cls,
+                rank++));
+        }
+        return rows;
+    }
+}

src/food-market.web/src/App.tsx

@@ -41,6 +41,7 @@ import { SupplierReturnEditPage } from '@/pages/SupplierReturnEditPage'
 import { SalesReportPage } from '@/pages/SalesReportPage'
 import { StockReportPage } from '@/pages/StockReportPage'
 import { ProfitReportPage } from '@/pages/ProfitReportPage'
+import { AbcReportPage } from '@/pages/AbcReportPage'
 import { RetailSalesPage } from '@/pages/RetailSalesPage'
 import { RetailSaleEditPage } from '@/pages/RetailSaleEditPage'
 import { AppLayout } from '@/components/AppLayout'
@@ -131,6 +132,7 @@ export default function App() {
               <Route path="/reports/sales" element={<SalesReportPage />} />
               <Route path="/reports/stock" element={<StockReportPage />} />
               <Route path="/reports/profit" element={<ProfitReportPage />} />
+              <Route path="/reports/abc" element={<AbcReportPage />} />
               <Route path="/sales/retail" element={<RetailSalesPage />} />
               <Route path="/sales/retail/new" element={<RetailSaleEditPage />} />
               <Route path="/sales/retail/:id" element={<RetailSaleEditPage />} />

src/food-market.web/src/components/AppLayout.tsx

@@ -7,7 +7,7 @@ import { cn } from '@/lib/utils'
 import {
   LayoutDashboard, Package, FolderTree, Ruler, Tag,
   Users, Warehouse, Store as StoreIcon, LogOut, Download, UserCog, Shield, ShieldCheck,
-  Boxes, History, TruckIcon, ShoppingCart, Settings, Menu, X, PackagePlus, PackageMinus, ArrowRightLeft, ClipboardCheck, Undo2, BarChart3, TrendingUp,
+  Boxes, History, TruckIcon, ShoppingCart, Settings, Menu, X, PackagePlus, PackageMinus, ArrowRightLeft, ClipboardCheck, Undo2, BarChart3, TrendingUp, Target,
 } from 'lucide-react'
 import { Logo } from './Logo'
 import { SuperAdminAsOrgBanner } from './SuperAdminAsOrgBanner'
@@ -114,6 +114,7 @@ function buildNav(roles: string[]): NavSection[] {
       { to: '/reports/sales', icon: BarChart3, label: 'Продажи' },
       { to: '/reports/stock', icon: Boxes, label: 'Остатки на дату' },
       { to: '/reports/profit', icon: TrendingUp, label: 'Прибыль' },
+      { to: '/reports/abc', icon: Target, label: 'ABC-анализ' },
     ]})
   }
 

src/food-market.web/src/pages/AbcReportPage.tsx

@@ -0,0 +1,193 @@
+import { useState } from 'react'
+import { useQuery } from '@tanstack/react-query'
+import { Download } from 'lucide-react'
+import { api } from '@/lib/api'
+import { Button } from '@/components/Button'
+import { Field, Select } from '@/components/Field'
+import { DateField } from '@/components/DateField'
+import { useStores, useProductGroups } from '@/lib/useLookups'
+import { useOrgSettings } from '@/lib/useOrgSettings'
+import { type AbcReportRow } from '@/lib/types'
+
+const METRICS = [
+  { value: 'revenue', label: 'Выручка' },
+  { value: 'profit',  label: 'Прибыль' },
+  { value: 'margin',  label: 'Маржа' },
+] as const
+
+const CLASS_COLOR: Record<string, string> = {
+  A: 'bg-green-100 text-green-800',
+  B: 'bg-yellow-100 text-yellow-800',
+  C: 'bg-red-100 text-red-800',
+}
+
+/** ABC-анализ. Топ-товары по выручке/прибыли/марже с распределением по
+ * классам Парето (80/15/5). Визуализация — цветные плашки класса и
+ * полоса накопительной доли. */
+export function AbcReportPage() {
+  const todayIso = () => new Date().toISOString().slice(0, 10)
+  const monthAgoIso = () => {
+    const d = new Date(); d.setDate(d.getDate() - 30)
+    return d.toISOString().slice(0, 10)
+  }
+
+  const [from, setFrom] = useState<string>(monthAgoIso())
+  const [to, setTo] = useState<string>(todayIso())
+  const [metric, setMetric] = useState<string>('revenue')
+  const [storeId, setStoreId] = useState<string>('')
+  const [productGroupId, setProductGroupId] = useState<string>('')
+
+  const stores = useStores()
+  const groups = useProductGroups()
+  const org = useOrgSettings()
+  const fractional = org.data?.allowFractionalPrices ?? false
+  const moneyFmt = fractional
+    ? { minimumFractionDigits: 2, maximumFractionDigits: 2 }
+    : { maximumFractionDigits: 0 }
+
+  const params = (extra: Record<string, string> = {}) => {
+    const p = new URLSearchParams({
+      from: new Date(from).toISOString(),
+      to: new Date(`${to}T23:59:59`).toISOString(),
+      metric,
+      ...extra,
+    })
+    if (storeId) p.set('storeId', storeId)
+    if (productGroupId) p.set('productGroupId', productGroupId)
+    return p
+  }
+
+  const rep = useQuery({
+    queryKey: ['abc-report', from, to, metric, storeId, productGroupId],
+    queryFn: async () => (await api.get<AbcReportRow[]>(`/api/reports/abc?${params()}`)).data,
+  })
+
+  const exportFile = async (format: 'csv' | 'xlsx') => {
+    const resp = await api.get(`/api/reports/abc/export?${params({ format })}`, { responseType: 'blob' })
+    const blob = new Blob([resp.data])
+    const url = URL.createObjectURL(blob)
+    const a = document.createElement('a')
+    a.href = url
+    const cd = resp.headers['content-disposition'] as string | undefined
+    const match = cd?.match(/filename="?([^";]+)"?/i)
+    a.download = match?.[1] ?? `abc-report.${format}`
+    document.body.appendChild(a)
+    a.click()
+    a.remove()
+    URL.revokeObjectURL(url)
+  }
+
+  const counts = { A: 0, B: 0, C: 0 } as Record<string, number>
+  rep.data?.forEach((r) => { counts[r.abcClass] = (counts[r.abcClass] ?? 0) + 1 })
+  const total = rep.data?.length ?? 0
+  const totalValue = rep.data?.reduce((s, r) => s + r.metricValue, 0) ?? 0
+
+  return (
+    <div className="flex flex-col h-full">
+      <div className="px-6 py-4 border-b border-slate-200 dark:border-slate-800 bg-white dark:bg-slate-900">
+        <h1 className="text-lg font-semibold text-slate-900 dark:text-slate-100">Отчёт «ABC-анализ»</h1>
+        <p className="text-xs text-slate-500 mt-1">
+          Топ-товары по выбранной метрике с разбиением A/B/C по правилу Парето (80/15/5).
+        </p>
+      </div>
+      <div className="flex-1 overflow-auto">
+        <div className="max-w-6xl mx-auto p-3 sm:p-6 space-y-4">
+          <section className="bg-white dark:bg-slate-900 rounded-lg border border-slate-200 dark:border-slate-800 p-4">
+            <div className="grid grid-cols-1 md:grid-cols-5 gap-x-4 gap-y-3 items-end">
+              <Field label="От">
+                <DateField value={from} onChange={(v) => setFrom(v ?? todayIso())} />
+              </Field>
+              <Field label="До">
+                <DateField value={to} onChange={(v) => setTo(v ?? todayIso())} />
+              </Field>
+              <Field label="Метрика">
+                <Select value={metric} onChange={(e) => setMetric(e.target.value)}>
+                  {METRICS.map((m) => <option key={m.value} value={m.value}>{m.label}</option>)}
+                </Select>
+              </Field>
+              <Field label="Склад">
+                <Select value={storeId} onChange={(e) => setStoreId(e.target.value)}>
+                  <option value="">Все</option>
+                  {stores.data?.map((s) => <option key={s.id} value={s.id}>{s.name}</option>)}
+                </Select>
+              </Field>
+              <Field label="Группа товаров">
+                <Select value={productGroupId} onChange={(e) => setProductGroupId(e.target.value)}>
+                  <option value="">Все</option>
+                  {groups.data?.map((g) => <option key={g.id} value={g.id}>{g.name}</option>)}
+                </Select>
+              </Field>
+            </div>
+            <div className="mt-4 flex flex-wrap gap-3 items-center justify-between">
+              <div className="flex gap-2 text-sm">
+                <span className={`px-3 py-1.5 rounded ${CLASS_COLOR.A}`}>A: {counts.A ?? 0}</span>
+                <span className={`px-3 py-1.5 rounded ${CLASS_COLOR.B}`}>B: {counts.B ?? 0}</span>
+                <span className={`px-3 py-1.5 rounded ${CLASS_COLOR.C}`}>C: {counts.C ?? 0}</span>
+                <span className="px-3 py-1.5 rounded bg-slate-50 dark:bg-slate-800/60">
+                  Всего: {total} · итог метрики: <span className="font-mono font-semibold">{totalValue.toLocaleString('ru', moneyFmt)}</span>
+                </span>
+              </div>
+              <div className="flex gap-2">
+                <Button type="button" variant="secondary" size="sm" onClick={() => exportFile('csv')}>
+                  <Download className="w-4 h-4" /> CSV
+                </Button>
+                <Button type="button" variant="secondary" size="sm" onClick={() => exportFile('xlsx')}>
+                  <Download className="w-4 h-4" /> XLSX
+                </Button>
+              </div>
+            </div>
+          </section>
+
+          <section className="bg-white dark:bg-slate-900 rounded-lg border border-slate-200 dark:border-slate-800 p-4">
+            {rep.isLoading && <div className="text-sm text-slate-500 py-6 text-center">Загружаю…</div>}
+            {!rep.isLoading && (rep.data?.length ?? 0) === 0 && (
+              <div className="text-sm text-slate-500 py-6 text-center">За период нет продаж.</div>
+            )}
+            {!rep.isLoading && rep.data && rep.data.length > 0 && (
+              <div className="overflow-x-auto">
+                <table className="w-full text-sm">
+                  <thead className="text-left">
+                    <tr className="border-b border-slate-200 dark:border-slate-700">
+                      <th className="py-2 pr-3 font-medium text-xs uppercase text-slate-500 w-[60px]">Ранг</th>
+                      <th className="py-2 px-3 font-medium text-xs uppercase text-slate-500 w-[60px]">Класс</th>
+                      <th className="py-2 px-3 font-medium text-xs uppercase text-slate-500">Товар</th>
+                      <th className="py-2 px-3 font-medium text-xs uppercase text-slate-500 w-[110px]">Артикул</th>
+                      <th className="py-2 px-3 font-medium text-xs uppercase text-slate-500 w-[150px] text-right">Метрика</th>
+                      <th className="py-2 px-3 font-medium text-xs uppercase text-slate-500 w-[100px] text-right">Доля,%</th>
+                      <th className="py-2 px-3 font-medium text-xs uppercase text-slate-500 w-[200px]">Накопит.</th>
+                    </tr>
+                  </thead>
+                  <tbody>
+                    {rep.data.map((r) => (
+                      <tr key={r.productId} className="border-b border-slate-100 dark:border-slate-800 hover:bg-slate-50 dark:hover:bg-slate-800/30">
+                        <td className="py-2 pr-3 text-slate-500">{r.rank}</td>
+                        <td className="py-2 px-3">
+                          <span className={`inline-block w-6 h-6 rounded text-center text-xs font-semibold leading-6 ${CLASS_COLOR[r.abcClass] ?? 'bg-slate-100 text-slate-700'}`}>{r.abcClass}</span>
+                        </td>
+                        <td className="py-2 px-3">{r.productName}</td>
+                        <td className="py-2 px-3 text-slate-500">{r.productArticle ?? '—'}</td>
+                        <td className="py-2 px-3 text-right font-mono">{r.metricValue.toLocaleString('ru', moneyFmt)}</td>
+                        <td className="py-2 px-3 text-right font-mono text-slate-500">{r.share.toFixed(2)}</td>
+                        <td className="py-2 px-3">
+                          <div className="flex items-center gap-2">
+                            <div className="flex-1 h-2 bg-slate-100 dark:bg-slate-800 rounded overflow-hidden">
+                              <div
+                                className={r.abcClass === 'A' ? 'bg-green-500' : r.abcClass === 'B' ? 'bg-yellow-500' : 'bg-red-500'}
+                                style={{ width: `${Math.min(100, r.cumulativeShare)}%`, height: '100%' }}
+                              />
+                            </div>
+                            <span className="font-mono text-xs text-slate-500 w-[55px] text-right">{r.cumulativeShare.toFixed(1)}%</span>
+                          </div>
+                        </td>
+                      </tr>
+                    ))}
+                  </tbody>
+                </table>
+              </div>
+            )}
+          </section>
+        </div>
+      </div>
+    </div>
+  )
+}

tests/food-market.IntegrationTests/AbcReportTests.cs

@@ -0,0 +1,158 @@
+using System.Net.Http.Json;
+using System.Text.Json;
+using FluentAssertions;
+using foodmarket.IntegrationTests.Support;
+using Xunit;
+
+namespace foodmarket.IntegrationTests;
+
+[Collection(ApiCollection.Name)]
+public class AbcReportTests
+{
+    private readonly ApiFactory _factory;
+    public AbcReportTests(ApiFactory factory) => _factory = factory;
+    private static string RandomBarcode()
+        => string.Concat(Enumerable.Range(0, 13).Select(_ => Random.Shared.Next(0, 10)));
+
+    /// <summary>3 товара с явно разной долей выручки → классы A/B/C по Парето.</summary>
+    [Fact]
+    public async Task Pareto_distribution_A_B_C()
+    {
+        var api = new ApiActor(_factory.CreateClient());
+        await api.SignupAndLoginAsync($"abc-{Guid.NewGuid():N}");
+        var refs = await api.LoadRefsAsync();
+        var pBig   = await api.CreateProductAsync(refs, $"BIG-{Guid.NewGuid():N}", 100m, RandomBarcode());
+        var pMed   = await api.CreateProductAsync(refs, $"MED-{Guid.NewGuid():N}", 100m, RandomBarcode());
+        var pSmall = await api.CreateProductAsync(refs, $"SML-{Guid.NewGuid():N}", 100m, RandomBarcode());
+
+        // Подкормим склад.
+        foreach (var pid in new[] { pBig, pMed, pSmall })
+        {
+            var e = await api.Http.PostAsJsonAsync("/api/inventory/enters", new {
+                date = DateTime.UtcNow, storeId = refs.StoreId, currencyId = refs.CurrencyId,
+                notes = "seed", lines = new[] { new { productId = pid, quantity = 100m, unitCost = 10m } } });
+            e.EnsureSuccessStatusCode();
+            var eid = (await e.Content.ReadFromJsonAsync<JsonElement>()).GetProperty("id").GetString();
+            (await api.Http.PostAsJsonAsync($"/api/inventory/enters/{eid}/post", new { })).EnsureSuccessStatusCode();
+        }
+
+        // Продажи: BIG = 800, MED = 150, SML = 50 → итого 1000.
+        // A = накопительно 80% (BIG), B = 95% (+ MED = 95%), C = остаток (SML).
+        async Task Sale(string pid, decimal qty, decimal price)
+        {
+            var resp = await api.Http.PostAsJsonAsync("/api/sales/retail", new {
+                date = DateTime.UtcNow, storeId = refs.StoreId, retailPointId = (string?)null,
+                customerId = (string?)null, currencyId = refs.CurrencyId,
+                payment = 0, paidCash = qty * price, paidCard = 0m,
+                lines = new[] { new { productId = pid, quantity = qty, unitPrice = price, discount = 0m, vatPercent = 12m } },
+                notes = "sale" });
+            resp.EnsureSuccessStatusCode();
+            var sid = (await resp.Content.ReadFromJsonAsync<JsonElement>()).GetProperty("id").GetString();
+            (await api.Http.PostAsJsonAsync($"/api/sales/retail/{sid}/post", new { })).EnsureSuccessStatusCode();
+        }
+        await Sale(pBig, 8m, 100m);
+        await Sale(pMed, 15m, 10m);
+        await Sale(pSmall, 5m, 10m);
+
+        var rep = await api.GetJsonAsync("/api/reports/abc?metric=revenue");
+        var arr = rep.EnumerateArray().ToList();
+        arr.Should().HaveCountGreaterOrEqualTo(3);
+
+        var big = arr.First(x => x.GetProperty("productId").GetString() == pBig);
+        var med = arr.First(x => x.GetProperty("productId").GetString() == pMed);
+        var small = arr.First(x => x.GetProperty("productId").GetString() == pSmall);
+        big.GetProperty("abcClass").GetString().Should().Be("A");
+        med.GetProperty("abcClass").GetString().Should().Be("B");
+        small.GetProperty("abcClass").GetString().Should().Be("C");
+
+        // Накопительная доля C должна быть 100%.
+        small.GetProperty("cumulativeShare").GetDecimal().Should().BeApproximately(100m, 0.5m);
+    }
+
+    [Fact]
+    public async Task Empty_period_returns_empty()
+    {
+        var api = new ApiActor(_factory.CreateClient());
+        await api.SignupAndLoginAsync($"abc-emp-{Guid.NewGuid():N}");
+        var pastFrom = DateTime.UtcNow.AddYears(-5).ToString("o");
+        var pastTo = DateTime.UtcNow.AddYears(-4).ToString("o");
+        var rep = await api.GetJsonAsync($"/api/reports/abc?from={Uri.EscapeDataString(pastFrom)}&to={Uri.EscapeDataString(pastTo)}");
+        rep.EnumerateArray().Should().BeEmpty();
+    }
+
+    [Fact]
+    public async Task Profit_metric_orders_by_margin()
+    {
+        var api = new ApiActor(_factory.CreateClient());
+        await api.SignupAndLoginAsync($"abc-prft-{Guid.NewGuid():N}");
+        var refs = await api.LoadRefsAsync();
+        var supplierId = await api.CreateCounterpartyAsync($"S-{Guid.NewGuid():N}");
+        // pA: 5 шт по 100 — высокая выручка, но низкая маржа (cost 80).
+        // pB: 2 шт по 100 — низкая выручка, но высокая маржа (cost 10).
+        var pA = await api.CreateProductAsync(refs, $"A-{Guid.NewGuid():N}", 100m, RandomBarcode());
+        var pB = await api.CreateProductAsync(refs, $"B-{Guid.NewGuid():N}", 100m, RandomBarcode());
+        async Task Supply(string pid, decimal qty, decimal cost)
+        {
+            var s = await api.Http.PostAsJsonAsync("/api/purchases/supplies", new {
+                date = DateTime.UtcNow, supplierId, storeId = refs.StoreId, currencyId = refs.CurrencyId,
+                notes = "in", lines = new[] { new { productId = pid, quantity = qty, unitPrice = cost } } });
+            s.EnsureSuccessStatusCode();
+            var sid = (await s.Content.ReadFromJsonAsync<JsonElement>()).GetProperty("id").GetString();
+            (await api.Http.PostAsJsonAsync($"/api/purchases/supplies/{sid}/post", new { })).EnsureSuccessStatusCode();
+        }
+        await Supply(pA, 10m, 80m);
+        await Supply(pB, 10m, 10m);
+
+        async Task Sale(string pid, decimal qty, decimal price)
+        {
+            var resp = await api.Http.PostAsJsonAsync("/api/sales/retail", new {
+                date = DateTime.UtcNow, storeId = refs.StoreId, retailPointId = (string?)null,
+                customerId = (string?)null, currencyId = refs.CurrencyId,
+                payment = 0, paidCash = qty * price, paidCard = 0m,
+                lines = new[] { new { productId = pid, quantity = qty, unitPrice = price, discount = 0m, vatPercent = 12m } },
+                notes = "sale" });
+            resp.EnsureSuccessStatusCode();
+            var sid = (await resp.Content.ReadFromJsonAsync<JsonElement>()).GetProperty("id").GetString();
+            (await api.Http.PostAsJsonAsync($"/api/sales/retail/{sid}/post", new { })).EnsureSuccessStatusCode();
+        }
+        await Sale(pA, 5m, 100m);  // profit = 500 − 5*80 = 100
+        await Sale(pB, 2m, 100m);  // profit = 200 − 2*10 = 180
+
+        // По revenue: A=500 > B=200, A первый (rank 1).
+        var byRev = await api.GetJsonAsync("/api/reports/abc?metric=revenue");
+        byRev.EnumerateArray().First().GetProperty("productId").GetString().Should().Be(pA);
+
+        // По profit: B=180 > A=100, B первый (rank 1).
+        var byProf = await api.GetJsonAsync("/api/reports/abc?metric=profit");
+        byProf.EnumerateArray().First().GetProperty("productId").GetString().Should().Be(pB);
+    }
+
+    [Fact]
+    public async Task Tenant_isolation_abc()
+    {
+        var a = new ApiActor(_factory.CreateClient());
+        var b = new ApiActor(_factory.CreateClient());
+        await a.SignupAndLoginAsync($"abc-iso-a-{Guid.NewGuid():N}");
+        await b.SignupAndLoginAsync($"abc-iso-b-{Guid.NewGuid():N}");
+        var refsA = await a.LoadRefsAsync();
+        var pA = await a.CreateProductAsync(refsA, $"PA-{Guid.NewGuid():N}", 100m, RandomBarcode());
+
+        var e = await a.Http.PostAsJsonAsync("/api/inventory/enters", new {
+            date = DateTime.UtcNow, storeId = refsA.StoreId, currencyId = refsA.CurrencyId,
+            notes = "seed", lines = new[] { new { productId = pA, quantity = 5m, unitCost = 10m } } });
+        e.EnsureSuccessStatusCode();
+        var eid = (await e.Content.ReadFromJsonAsync<JsonElement>()).GetProperty("id").GetString();
+        (await a.Http.PostAsJsonAsync($"/api/inventory/enters/{eid}/post", new { })).EnsureSuccessStatusCode();
+        var sale = await a.Http.PostAsJsonAsync("/api/sales/retail", new {
+            date = DateTime.UtcNow, storeId = refsA.StoreId, retailPointId = (string?)null,
+            customerId = (string?)null, currencyId = refsA.CurrencyId, payment = 0, paidCash = 100m, paidCard = 0m,
+            lines = new[] { new { productId = pA, quantity = 1m, unitPrice = 100m, discount = 0m, vatPercent = 12m } },
+            notes = "s" });
+        sale.EnsureSuccessStatusCode();
+        var sid = (await sale.Content.ReadFromJsonAsync<JsonElement>()).GetProperty("id").GetString();
+        (await a.Http.PostAsJsonAsync($"/api/sales/retail/{sid}/post", new { })).EnsureSuccessStatusCode();
+
+        var repB = await b.GetJsonAsync("/api/reports/abc");
+        repB.EnumerateArray().Should().NotContain(x => x.GetProperty("productId").GetString() == pA);
+    }
+}