Invoice set pricing: wire editor + align editor/backend contract

Front-end (fis.inv_shared.js / fis.inv_txt_de.js, rebuilt bundles):
- 3-way set display switch (setprice/itemprices/setonly) via admin.setmode,
  emitted into InvoiceOptions by FdsInvoiceData.BuildInvoiceOptions.
- Each request block now posts items[] in the backend contract shape
  (title/desc/qty/price_net/total_net + set type/setId tags) via itemToContract.
- invcPayload normalises the editor model to the field names BuildInvoiceParams
  reads (sms totals -> new.total_net/total_gross, invoicetitle->title,
  loc->provisionlocation, admin.paymentterms->new.paymentterm, CustomerId->customerid).

Back-end:
- BuildInvoiceOptions adds the setmode token alongside §13b.
- VAT rate+amount now taken from sms.vat (HighestVat) instead of the broken
  items 'is List<object>' detection that pinned the rate to 19.
- InvoiceSetPricing blanks price/total cells for text/title heading lines.

Tests: set-pricing text-line blanking, HighestVat selection/parsing, updated
the VAT param test to the sms.vat contract. 180 passing.

Note: the second VAT slot (InvoiceVAT_2) stays unused by design; mixed-rate
invoices store only the highest rate (pre-existing, accepted).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Fuchs.Tests/FdsDataTests.cs

@@ -42,11 +42,11 @@ public class FdsDataTests
     [Fact]
     public void FdsInvoiceData_BuildInvoiceParams_PicksHighestVatAndMapsFields()
     {
-        // two line items with different VAT rates → highest (19) selected
+        // VAT comes from the sms.vat map (rate → amount); highest rate (19) selected.
         var jo = JObject.Parse(
             "{ \"admin\": { \"type\": \"R\", \"customerid\": \"7\", \"p13b\": false }, " +
-            "  \"new\":   { \"title\": \"Bad\", \"total_gross\": \"119\", \"total_net\": \"100\", \"vat_19_net\": \"100\", \"paymentterm\": \"10d\" }, " +
-            "  \"req\": [ { \"items\": [ { \"vat\": \"7%\" }, { \"vat\": \"19%\" } ] } ] }");
+            "  \"new\":   { \"title\": \"Bad\", \"total_gross\": \"119\", \"total_net\": \"100\", \"paymentterm\": \"10d\" }, " +
+            "  \"sms\":   { \"vat\": { \"7,0%\": 7.0, \"19,0%\": 19.0 } } }");
         var inv = new FdsInvoiceData(jo);
 
         var pl = inv.BuildInvoiceParams(change: false, invId: "");

Fuchs.Tests/InvoiceOptionsTests.cs

@@ -0,0 +1,111 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Fuchs.intranet;
+using Newtonsoft.Json.Linq;
+using Xunit;
+using static OCORE.OCORE_dictionaries;
+
+namespace Fuchs.Tests;
+
+/// <summary>
+/// Verifies that the posted <c>admin</c> flags map to the <c>@InvoiceOptions</c>
+/// CSV the backend persists — the channel both §13b and the set-pricing
+/// <c>setmode</c> token ride. The PDF reads the mode back via
+/// <see cref="InvoiceSetPricing.ModeFromInvoiceOptions"/>.
+/// </summary>
+public class InvoiceOptionsTests
+{
+    private static string InvoiceOptionsFor(object? admin)
+    {
+        var root = new JObject();
+        if (admin != null) root["admin"] = JObject.FromObject(admin);
+        var data = new FdsInvoiceData(root);
+        var p = data.BuildInvoiceParams(change: false, invId: "")
+                    .First(x => x.ParameterName == "@InvoiceOptions");
+        return p.Value is DBNull or null ? "" : p.Value!.ToString()!;
+    }
+
+    [Fact]
+    public void NoFlags_EmptyOptions()
+        => Assert.Equal("", InvoiceOptionsFor(new { type = "r" }));
+
+    [Fact]
+    public void DefaultSetPrice_OmitsToken()
+        => Assert.Equal("", InvoiceOptionsFor(new { type = "r", setmode = "setprice" }));
+
+    [Theory]
+    [InlineData("itemprices", "setmode:itemprices")]
+    [InlineData("setonly",    "setmode:setonly")]
+    [InlineData("ITEMPRICES", "setmode:itemprices")] // case-insensitive
+    public void SetMode_EmitsToken(string mode, string expected)
+        => Assert.Equal(expected, InvoiceOptionsFor(new { type = "r", setmode = mode }));
+
+    [Fact]
+    public void UnknownSetMode_OmitsToken()
+        => Assert.Equal("", InvoiceOptionsFor(new { type = "r", setmode = "garbage" }));
+
+    [Fact]
+    public void P13bOnly_EmitsLegacyToken()
+        => Assert.Equal("§13b", InvoiceOptionsFor(new { type = "r", p13b = true }));
+
+    [Fact]
+    public void P13bAndSetMode_EmitsBoth()
+        => Assert.Equal("§13b,setmode:setonly", InvoiceOptionsFor(new { type = "r", p13b = true, setmode = "setonly" }));
+
+    // ── VAT: highest rate + amount taken from the sms.vat map ─────────────────
+    private static GenericObjectDictionary SmsWithVat(params (string rate, double amount)[] vat)
+    {
+        var map = new Dictionary<string, double>();
+        foreach (var (r, a) in vat) map[r] = a;
+        return new GenericObjectDictionary(new Dictionary<string, object> { ["vat"] = JObject.FromObject(map) });
+    }
+
+    [Fact]
+    public void HighestVat_PicksHighestRate_GermanFormatted()
+    {
+        var (rate, amt) = FdsInvoiceData.HighestVat(SmsWithVat(("19,0%", 38.0), ("7,0%", 7.0)));
+        Assert.Equal("19", rate);    // integer, invariant
+        Assert.Equal("38", amt);
+    }
+
+    [Fact]
+    public void HighestVat_NonIntegerRate_Preserved()
+    {
+        var (rate, amt) = FdsInvoiceData.HighestVat(SmsWithVat(("10,5%", 5.25)));
+        Assert.Equal("10.5", rate);  // invariant decimal point — safe for numeric(5,2)
+        Assert.Equal("5.25", amt);
+    }
+
+    [Fact]
+    public void HighestVat_EmptyOrMissing_ReturnsZero()
+    {
+        Assert.Equal(("0", "0"), FdsInvoiceData.HighestVat(null));
+        Assert.Equal(("0", "0"), FdsInvoiceData.HighestVat(new GenericObjectDictionary(new Dictionary<string, object>())));
+    }
+
+    [Fact]
+    public void HighestVat_FlowsIntoParams()
+    {
+        var root = new JObject
+        {
+            ["admin"] = JObject.FromObject(new { type = "r" }),
+            ["sms"]   = JObject.FromObject(new Dictionary<string, object>
+            {
+                ["vat"] = new Dictionary<string, double> { ["19,0%"] = 38.0 }
+            })
+        };
+        var pars = new FdsInvoiceData(root).BuildInvoiceParams(false, "");
+        Assert.Equal("19", pars.First(p => p.ParameterName == "@InvoiceVAT_1").Value);
+    }
+
+    [Fact]
+    public void ModeFromInvoiceOptions_RoundTripsBackendEmission()
+    {
+        // The token this side emits must parse back to the same mode on the PDF side.
+        Assert.Equal(SetDisplayMode.ItemPrices,
+            InvoiceSetPricing.ModeFromInvoiceOptions(InvoiceOptionsFor(new { type = "r", setmode = "itemprices" })));
+        Assert.Equal(SetDisplayMode.SetOnly,
+            InvoiceSetPricing.ModeFromInvoiceOptions(InvoiceOptionsFor(new { type = "r", p13b = true, setmode = "setonly" })));
+    }
+}

Fuchs.Tests/InvoiceSetPricingTests.cs

@@ -144,6 +144,40 @@ public class InvoiceSetPricingTests
         Assert.All(lines, l => Assert.False(l.IsSetHeader));
     }
 
+    // ── Text/Title lines never show a price (any mode) ────────────────────────
+    private static Dictionary<string, object?> TextLine(string title) => new()
+    {
+        ["type"] = "title", ["title"] = title, ["qty"] = "", ["price_net"] = "", ["total_net"] = ""
+    };
+
+    [Fact]
+    public void Build_TextLine_Standalone_NoPrice()
+    {
+        var items = new List<Dictionary<string, object?>>
+        {
+            TextLine("Leistungszeitraum 2026"),
+            Standalone("Anfahrt", "50.00", "50.00")
+        };
+        var lines = InvoiceSetPricing.Build(items, SetDisplayMode.SetPrice);
+        Assert.False(lines[0].ShowPrice);   // heading — blank price
+        Assert.True(lines[1].ShowPrice);    // real item — priced
+    }
+
+    [Fact]
+    public void Build_TextLine_AsSetMember_NoPriceEvenInItemPrices()
+    {
+        var items = new List<Dictionary<string, object?>>
+        {
+            SetHeader("10", "Bad-Komplettset", "1000.00"),
+            new() { ["type"] = "title", ["setId"] = "10", ["title"] = "Hinweis", ["total_net"] = "" },
+            Member("10", "Waschbecken", "600.00", "600.00")
+        };
+        var lines = InvoiceSetPricing.Build(items, SetDisplayMode.ItemPrices);
+        var note = lines.First(l => l.Title == "Hinweis");
+        Assert.False(note.ShowPrice);       // text member stays blank
+        Assert.True(lines.First(l => l.Title == "Waschbecken").ShowPrice);
+    }
+
     // ── Set price equals sum of member prices across modes (no double counting) ─
     [Fact]
     public void SetPrice_EqualsSumOfMembers()

Fuchs/Docs/INVOICE_SET_PRICING.md

@@ -29,23 +29,59 @@ Three display modes (switchable in the invoice editor):
   set header line is rendered emphasised. Invoices without sets pass through
   unchanged.
 
-## Front-end contract (to wire in the invoice editor)
+## Front-end contract (implemented in the invoice editor)
 
-The editor already knows the set structure (from `fds__prepInvoice`) and assembles
-the `invc` JSON. To drive the modes it must, when sending the invoice:
+Wired in `Fuchs/js/intranet/modules/fis.inv_shared.js` (bundled to
+`wwwroot/web/fis.inv.de.js` via gulp `min:js`):
 
-1. **Mode** — add a token to `inv.InvoiceOptions` (CSV, alongside `§13b`):
-   - `setmode:setprice` (default — may be omitted), `setmode:itemprices`, or `setmode:setonly`.
-   A 3-way switch in the editor sets this token.
+1. **Mode** — a 3-way switch (`$inv.ssetmode`, menu entry `setm`, label
+   `$ict.setm`) writes the choice onto `admin.setmode`
+   (`setprice` | `itemprices` | `setonly`). The back-end
+   `FdsInvoiceData.BuildInvoiceOptions` turns that into the
+   `setmode:<mode>` token inside `@InvoiceOptions` (default `setprice` omitted),
+   persisted by `fds__createInvoice_Details` and read back by
+   `InvoiceSetPricing.ModeFromInvoiceOptions`. This rides the **same `admin`
+   channel as `§13b`** (the posted payload is `{admin, req, sms, new}` — `inv`
+   is not sent).
 
-2. **Item flags** — in each service request's `items[]`:
-   - the **set header** item: `type: "set"`, `id: "<setId>"`, and `total_net` =
-     the set price (or `0` to let the back-end sum the members);
-   - each **member** item: `setId: "<setId>"` (matching the header's id).
-   - standalone items need no extra fields.
+2. **Item shape** — `$inv.invSumUpdate` now posts each request block's
+   `items[]` in the back-end contract shape via `$inv.itemToContract`:
+   `{ id, type, title, desc, qty, price_net, total_net, vat }`. (Previously the
+   editor only posted the legacy on-screen `itm`/`co` objects, which
+   `FdsInvoiceData.InvoiceItems` does not read — so line items never reached the
+   C# PDF. This change closes that gap for **all** invoices, not just sets.)
 
-That is the entire contract — the back-end does the rest. The editor's running
-**total stays the member sum in every mode**, matching the registration balance.
+3. **Set flags** — `invSumUpdate` tags items as it builds `items[]`: an item with
+   `type === 'set'` is a header (`id` = its set id); the **following items in the
+   same block become its members** (`setId` = the header's id) until the next set
+   header. `mfr__items` has a `Type='set'` header but **no explicit member link**,
+   so this "header claims the following items in its block" rule is the convention
+   — adjust in `invSumUpdate` if mfr later exposes a real grouping.
+
+### Editor → backend field normalization (`$inv.invcPayload`)
+The editor's internal model keeps the long-standing key names, but the migrated C#
+`BuildInvoiceParams` reads different ones. At post time `$inv.invcPayload(d)` maps the
+working model onto the exact field names the back-end reads (non-destructively):
+`sms.ttn → new.total_net`, `sms.ttb → new.total_gross`, each `sms.vat` rate →
+`new.vat_<rate>_net`, `new.invoicetitle → new.title`, `new.loc → new.provisionlocation`,
+`admin.paymentterms → new.paymentterm`, `admin.CustomerId → admin.customerid`. Both
+`req/save` and `req/sprep|sedit` post through it, so titles/balances/VAT now reach the
+backend correctly.
+
+VAT (rate **and** amount) is taken by the backend directly from the posted `sms.vat`
+map via `FdsInvoiceData.HighestVat` (highest rate wins) — `invcPayload` therefore emits
+no per-rate `vat_*` keys.
+
+**Back-end fixes applied alongside the wiring:**
+- Heading/free-text lines (`type` `text`/`title`) now render a **blank** price/total
+  (`InvoiceSetPricing.IsNoPriceLine`), instead of `0,00 €`.
+- VAT rate detection no longer reads line items (the old `items is List<object>` test
+  failed on Newtonsoft `JArray` and pinned `@InvoiceVAT_1` to `19`); it now comes from
+  `sms.vat`, so non-19 % rates are stored correctly. Single-rate procs still store only
+  the highest rate.
+
+The editor's running **total stays the member sum in every mode**, matching the
+registration balance — switching modes is purely presentational.
 
 ### Why the switch lives in the editor
 Set grouping is only known where the request/item tree is rendered (front-end).
@@ -55,9 +91,9 @@ items — it does not re-implement the pricing rules.
 
 ## Persistence note
 Draft/preview PDFs render straight from the posted `invc` JSON, so the contract
-works end-to-end for previews immediately. For a **finalised** invoice to re-render
-in a chosen mode later, the per-item `type`/`setId` flags (and the `setmode`
-option) must be persisted with the stored invoice items
-(`fds__createInvoice_Details` / `fds__invoice_items`). `setmode` already persists
-via `InvoiceOptions`; persisting the per-item set tags is a small SSDT + create-proc
-change to make once the editor wiring is confirmed.
+works end-to-end for previews and creation. `setmode` persists via
+`InvoiceOptions`; the finalised document is rendered once and stored as a file, so
+re-rendering from line items is not needed for correctness. Persisting the
+per-item `type`/`setId` flags (an SSDT + `fds__createInvoice_Details` change) is
+only required if a finalised invoice must be **re-generated** from stored items in
+a different mode later — not done here.

Fuchs/code/FdsInvoiceData.cs

@@ -1,3 +1,4 @@
+using System.Globalization;
 using Microsoft.Data.SqlClient;
 using Newtonsoft.Json.Linq;
 using static OCORE.OCORE_dictionaries;
@@ -113,23 +114,10 @@ public class FdsInvoiceData
     internal List<SqlParameter> BuildInvoiceParams(bool change, string invId)
     {
         _ = change; _ = invId;
-        var vatsDic = new Dictionary<string, string>();
-        if (Req != null)
-        {
-            foreach (var rq in Req)
-            {
-                if (rq.TryGetValue("items", out var itmsObj) && itmsObj is List<object> itms)
-                {
-                    foreach (var itm in itms.OfType<Dictionary<string, object?>>())
-                    {
-                        string vatKey = itm.nz("vat", "").Replace("%", "").Trim();
-                        if (!string.IsNullOrEmpty(vatKey) && vatKey != "0")
-                            vatsDic.TryAdd(vatKey, vatsDic.TryGetValue(vatKey, out var ve) ? ve : "0");
-                    }
-                }
-            }
-        }
-        string vathigh = vatsDic.Keys.OrderByDescending(k => double.TryParse(k, out var d) ? d : 0).FirstOrDefault() ?? "19";
+        // VAT rate + amount come from the editor's computed sms.vat map (rate → amount),
+        // matching the legacy contract. Item-level VAT strings are German-formatted and
+        // single-rate procs only store one rate, so the highest rate wins.
+        var (vatRate, vatNet) = HighestVat(Sms);
 
         return new List<SqlParameter>
         {
@@ -137,8 +125,8 @@ public class FdsInvoiceData
             SQL_NVarChar("@InvoiceTitle",       NewValues?.nz("title") ?? ""),
             SQL_Float("@InvoiceBalance",        stringvalue: NewValues?.nz("total_gross") ?? "0"),
             SQL_Float("@InvoiceBalance_net",    stringvalue: NewValues?.nz("total_net") ?? "0"),
-            SQL_Float("@InvoiceVAT_net1",       stringvalue: NewValues?.nz($"vat_{vathigh}_net") ?? "0"),
-            SQL_VarChar("@InvoiceVAT_1",        vathigh),
+            SQL_Float("@InvoiceVAT_net1",       stringvalue: vatNet),
+            SQL_VarChar("@InvoiceVAT_1",        vatRate),
             SQL_VarChar("@PaymentTerm",         NewValues?.nz("paymentterm") ?? "", dbNull_IfEmpty: true),
             SQL_BigInt("@CustomerId",           Admin?.nz("customerid") ?? ""),
             SQL_VarChar("@SendToAddress",       RawInvoiceAddress),
@@ -147,8 +135,64 @@ public class FdsInvoiceData
             SQL_NVarChar("@CustomValues",       RawCustomValues, dbNull_IfEmpty: true),
             SQL_Float("@InvoiceService_net",    stringvalue: Sms?.nz("tscn") ?? "0"),
             SQL_Float("@InvoiceService_VAT",    stringvalue: Sms?.nz("tscvat") ?? "0"),
-            SQL_VarChar("@InvoiceOptions",
-                Admin?.no("p13b", false) is true ? "§13b" : "", dbNull_IfEmpty: true)
+            SQL_VarChar("@InvoiceOptions", BuildInvoiceOptions(), dbNull_IfEmpty: true)
         };
     }
+
+    /// <summary>
+    /// Builds the InvoiceOptions CSV from the posted admin flags.
+    /// <c>§13b</c> is the existing reverse-charge flag; <c>setmode:&lt;mode&gt;</c>
+    /// selects the set-pricing display mode (the default <c>setprice</c> is omitted).
+    /// Read back by <see cref="InvoiceSetPricing.ModeFromInvoiceOptions"/> (set mode)
+    /// and the §13b PDF note. Both ride the <c>admin</c> object the editor posts.
+    /// </summary>
+    internal string BuildInvoiceOptions()
+    {
+        var tokens = new List<string>();
+        if (Admin?.no("p13b", false) is true) tokens.Add("§13b");
+        string setmode = (Admin?.nz("setmode") ?? "").Trim().ToLowerInvariant();
+        if (setmode is "itemprices" or "setonly") tokens.Add("setmode:" + setmode);
+        return string.Join(",", tokens);
+    }
+
+    /// <summary>
+    /// Determines the highest VAT rate and its net VAT amount from the editor's
+    /// computed <c>sms.vat</c> map (rate string → amount), e.g. {"19,0%": 123.45}.
+    /// Mirrors the legacy contract (VAT comes from the totals block, not line items).
+    /// Returns invariant numeric strings — rate ("19") and amount ("123.45") — ready
+    /// for the <c>numeric</c> proc params. Empty/absent map → ("0","0").
+    /// </summary>
+    internal static (string rate, string netAmount) HighestVat(GenericObjectDictionary? sms)
+    {
+        if (sms == null || !sms.TryGetValue("vat", out var vobj) || vobj is null)
+            return ("0", "0");
+
+        bool found = false; double bestRate = 0, bestAmount = 0;
+        void Consider(string key, double amount)
+        {
+            double r = ParseRate(key);
+            if (!found || r > bestRate) { found = true; bestRate = r; bestAmount = amount; }
+        }
+
+        if (vobj is JObject jo)
+            foreach (var p in jo)
+                Consider(p.Key, p.Value is { } t && t.Type is JTokenType.Float or JTokenType.Integer ? t.Value<double>() : 0);
+        else if (vobj is IDictionary<string, object?> dict)
+            foreach (var kv in dict)
+                Consider(kv.Key, double.TryParse(Convert.ToString(kv.Value, CultureInfo.InvariantCulture),
+                    NumberStyles.Any, CultureInfo.InvariantCulture, out var a) ? a : 0);
+
+        if (!found) return ("0", "0");
+        string rate = bestRate == Math.Floor(bestRate)
+            ? ((long)bestRate).ToString(CultureInfo.InvariantCulture)
+            : bestRate.ToString(CultureInfo.InvariantCulture);
+        return (rate, bestAmount.ToString(CultureInfo.InvariantCulture));
+    }
+
+    /// <summary>Parses a VAT rate string ("19,0%", "7%", "19") to a number (German or invariant).</summary>
+    private static double ParseRate(string? key)
+    {
+        string s = (key ?? "").Replace("%", "").Trim().Replace(',', '.');
+        return double.TryParse(s, NumberStyles.Any, CultureInfo.InvariantCulture, out var d) ? d : 0;
+    }
 }

Fuchs/code/InvoiceSetPricing.cs

@@ -122,6 +122,17 @@ public static class InvoiceSetPricing
     private static bool IsSetHeader(Dictionary<string, object?> i) =>
         string.Equals(i.nz("type", ""), "set", StringComparison.OrdinalIgnoreCase);
 
+    /// <summary>
+    /// Text/Title lines are headings/free text with no price — their price/total
+    /// cells render blank (matching the editor and the legacy invoice), regardless
+    /// of the chosen mode.
+    /// </summary>
+    private static bool IsNoPriceLine(Dictionary<string, object?> i)
+    {
+        string t = i.nz("type", "").ToLowerInvariant();
+        return t is "text" or "title";
+    }
+
     private static string? SetIdOf(Dictionary<string, object?> i)
     {
         string s = i.nz("setId", "");
@@ -165,7 +176,7 @@ public static class InvoiceSetPricing
             Qty       = i.nz("qty", "1"),
             PriceNet  = price,
             TotalNet  = total,
-            ShowPrice = showPrice,
+            ShowPrice = showPrice && !IsNoPriceLine(i),  // headings/free text print no price
             IsSetHeader = false
         };
     }

Fuchs/js/intranet/modules/fis.inv_shared.js

@@ -96,6 +96,9 @@ $inv.eM = (r, re, opt) => {
     if ((opt || '').split(',').includes('p13b') === true) {
         m.push({ lbl: $ict.p13b, fnc: $inv.sp13b });
     }
+    if ((opt || '').split(',').includes('setm') === true) {
+        m.push({ lbl: $ict.setm, fnc: $inv.ssetmode });
+    }
     if (booln(r, false) === true) {
         m.push({ lbl: $ict.rel, fnc: $inv.rReload });
     }
@@ -258,7 +261,7 @@ $inv.ccInv = function (ev) {  //normale rechnung
             rif.tbl.children('tbody').each($inv.bdysort);
             rif.tbl.trigger('fds.inv');  /* trigger calculations */
 
-            $inv.eM(false, true, 'iss,p13b,ctp');
+            $inv.eM(false, true, 'iss,p13b,setm,ctp');
         }, complete: () => {
             o.c.trigger('modal_close');
         }
@@ -403,7 +406,7 @@ $inv.cntInv = function (data) {  //invoice continuation
 
             rif.tbl.children('tbody').each($inv.bdysort);
             rif.tbl.trigger('fds.inv');  /* trigger calculations */
-            $inv.eM(false, true, 'iss,p13b,ctp');
+            $inv.eM(false, true, 'iss,p13b,setm,ctp');
         }, complete: () => {
             o.c.trigger('modal_close');
         }
@@ -646,12 +649,19 @@ $inv.invSumUpdate = function () {
     };
     let bds = tbl.children('tbody');
     bds.each((bi, bdy) => {
-        let b = $(bdy), rx = b.data() || {}, i = [], bnet = 0, itm = b.find('tr.itm'), iso = 0, ipos = 0;
+        let b = $(bdy), rx = b.data() || {}, i = [], citems = [], cset = null, bnet = 0, itm = b.find('tr.itm'), iso = 0, ipos = 0;
         b.tC('empty', itm.length < 1);
         itm.each((ti, tx) => {
 
             let rrx = $(tx).data() || {}; csms(rrx, sms, rx.Id); bnet += (rrx.net_val || 0); i.push(rrx.co);
             //console.debug('rrx %o', rrx);
+            /* backend item contract (title/desc/qty/price_net/total_net + set flags), see InvoiceSetPricing.
+               Set grouping: an item of Type 'set' is a header that claims the following items in this
+               block as its members until the next set header (mfr__items has no explicit member link). */
+            let citem = $inv.itemToContract(rrx);
+            if (citem.type === 'set' && citem.id !== '') { cset = citem.id; }
+            else if (cset !== null && (citem.id || '') !== '') { citem.setId = cset; }
+            citems.push(citem);
             if (((typeof rrx.SortOrder === 'undefined' || rrx.SortOrder === null) ? -1 : rrx.SortOrder) > -1) {
                 if (['text', 'title'].includes((rrx.Type || 'other').toLowerCase()) === false) { ipos++; }
                 rrx.SortOrder = iso;
@@ -663,7 +673,7 @@ $inv.invSumUpdate = function () {
         //    f: b.find('tr.isum > td.isumval'), t: fnum(bnet, $rct.cst), n: bnet
         //});
         b.find('tr.isum > td.isumval').text(fnum(bnet, $rct.cst));
-        ba.push({ Id: rx.Id, nme: rx.Name, text: rx.text, itm: i, netval: bnet });
+        ba.push({ Id: rx.Id, nme: rx.Name, text: rx.text, itm: i, items: citems, netval: bnet });
     });
     let nonempty = tbl.find('tbody:not(.empty)').length;
     bds.find('tr.isum').tC('hidden', nonempty < 2);
@@ -838,6 +848,53 @@ $inv.sp13b = () => {
     }
     tbl.trigger('fds.inv');
 };
+/* Maps an item row's data to the backend item contract consumed by InvoiceSetPricing
+   / FuchsPdf.ApplyInvoice: { id, type, title (plain), desc (html), qty, price_net,
+   total_net, vat }. Set membership (type:'set' header + setId on members) is added by
+   the caller. The invoice total comes from the registration balance, so per-item
+   totals here are purely presentational. */
+$inv.itemToContract = function (rrx) {
+    rrx = rrx || {};
+    let oHtml = (e) => $$.d().append(e).html();
+    let type = (rrx.Type || '').toString().toLowerCase();
+    let ci = { id: (rrx.Id || '').toString(), type: type, title: '', desc: '', qty: '', price_net: '', total_net: (rrx.net_val || 0), vat: rrx.vat || '' };
+    if (rrx.co && rrx.co.typ === 'osum') {
+        /* combined single-sum line — the on-screen "title" is an HTML sub-table; render it as desc */
+        ci.desc = rrx.co.t || '';
+        ci.total_net = (rrx.net_val || 0);
+    } else if (['text', 'title'].includes(type) && (rrx.net_val || 0) === 0) {
+        /* heading / free-text line, no price */
+        ci.desc = rrx.htmltext || ((((rrx.NameOrNumber || '').substr(0, 1) !== '#') ? oHtml($$[0]('p').text(rrx.NameOrNumber || '')) : '') + (rrx.Note || ''));
+        ci.total_net = '';
+    } else {
+        /* normal priced item (incl. set headers, which carry their own set price or 0) */
+        ci.title = rrx.NameOrNumber || '';
+        ci.desc = rrx.Note || '';
+        ci.qty = rrx.quantity || ((rrx.quantityhours || 0) !== 0 ? (fnum(rrx.quantityhours) + (rrx.UnitString ? ' ' + rrx.UnitString : '')) : '');
+        ci.price_net = (rrx.net || 0);
+        ci.total_net = (rrx.net_val || 0);
+    }
+    return ci;
+};
+/* 3-way set-pricing display switch. Mirrors §13b: writes the choice onto admin.setmode,
+   which BuildInvoiceParams turns into the "setmode:<mode>" InvoiceOptions token the PDF reads. */
+$inv.ssetmode = () => {
+    let l = $('div.invoice_layout'), tbl = l.find('table.invi'), d = tbl.data();
+    d.admin = d.admin || {};
+    let cur = (d.admin.setmode || 'setprice'), o;
+    let btn = (mode) => $$.dc('btn', $ict.setmo[mode]).tC('selected', cur === mode).click(() => { o.c.trigger('modal_close'); $inv.setSetmode(mode); });
+    let fr = $$.dc('choicefrm').append([btn('setprice'), btn('itemprices'), btn('setonly')]);
+    o = $ocms.dlg(fr, { width: 800 });
+};
+$inv.setSetmode = (mode) => {
+    let l = $('div.invoice_layout'), tbl = l.find('table.invi'), d = tbl.data();
+    d.admin = d.admin || {};
+    d.admin.setmode = mode;                        /* posted in admin -> BuildInvoiceParams writes setmode: into InvoiceOptions */
+    d.inv = d.inv || {};                           /* keep a local InvoiceOptions reflection in sync (cosmetic) */
+    let opts = (d.inv.InvoiceOptions || '').split(',').filter(x => x !== '' && x.indexOf('setmode:') !== 0);
+    if (mode && mode !== 'setprice') { opts.push('setmode:' + mode); }
+    d.inv.InvoiceOptions = opts.join(',');
+};
 $inv.sctp = () => {
     let flds = $invcol.ctp;
     $ocms.dlgform(flds, {
@@ -857,12 +914,32 @@ $inv.sctp = () => {
         }, typedvalues: true
     });
 };
+/* Normalises the editor's working model into the exact field names the C# backend
+   (FdsInvoiceData.BuildInvoiceParams) reads, then returns the `invc` payload:
+   - balances/service sums come from `sms` (ttn/ttb), exposed on `new` as total_net/total_gross;
+   - every VAT rate's net amount is exposed as new.vat_<rate>_net (the backend reads the highest);
+   - new.invoicetitle -> new.title, new.loc -> new.provisionlocation, admin.paymentterms ->
+     new.paymentterm, admin.CustomerId -> admin.customerid.
+   Originals are kept alongside; the source objects are not mutated. */
+$inv.invcPayload = function (d) {
+    d = d || {};
+    let sms = d.sms || {}, nw = $.extend({}, d.new), adm = $.extend({}, d.admin);
+    nw.total_net = sms.ttn || 0;
+    nw.total_gross = sms.ttb || 0;
+    /* VAT (rate + amount) is taken by the backend straight from the posted sms.vat map
+       (FdsInvoiceData.HighestVat), so no per-rate new.vat_* keys are needed here. */
+    nw.title = (nw.invoicetitle != null ? nw.invoicetitle : (nw.title || ''));
+    nw.provisionlocation = (nw.loc != null ? nw.loc : (nw.provisionlocation || ''));
+    nw.paymentterm = (adm.paymentterms != null ? adm.paymentterms : (nw.paymentterm || ''));
+    adm.customerid = (adm.customerid != null ? adm.customerid : adm.CustomerId);
+    return { admin: adm, req: d.bai, sms: d.sms, new: nw };
+};
 $inv.ssave = () => {
     var l = $('div.invoice_layout'), d = l.find('table.invi').data();
     $inv.t_fds_inv();
     l.aC('freeze');
     $ocms.postXT({
-        url: $ocms.url('req/save'), data: { invc: JSON.stringify({ admin: d.admin, req: d.bai, sms: d.sms, new: d.new }), id: d.invid || '' }, success: (response) => {
+        url: $ocms.url('req/save'), data: { invc: JSON.stringify($inv.invcPayload(d)), id: d.invid || '' }, success: (response) => {
             $inv.cntInv({ id: response.id });
         }, error: () => {
             alert($ict.eis);
@@ -884,7 +961,7 @@ $inv.sprev = (change) => {
         }
     }
     $ocms.postXT({
-        url: $ocms.url('req/' + (change === true ?'sedit':'sprep')), data: { invc: JSON.stringify({ admin: d.admin, req: d.bai, sms: d.sms, new: d.new }), id: d.invid ||'' }, success: (response) => {
+        url: $ocms.url('req/' + (change === true ?'sedit':'sprep')), data: { invc: JSON.stringify($inv.invcPayload(d)), id: d.invid ||'' }, success: (response) => {
             l.rC('freeze');
             let c = $$.dc('imagecollection pdfpreview'), vhr = Math.round(vh() * 0.88), invid = response.id, invtp = response.total;
             if (invtp > 10) {

Fuchs/js/intranet/modules/fis.inv_txt_de.js

@@ -40,6 +40,12 @@
     eis: 'Der Rechnungsentwurf konnte nicht gespeichert werden.',
     iss: 'Zwischenstand speichern.',
     p13b: 'USt -> §13b',
+    setm: 'Set-Preisanzeige',
+    setmo: {
+        setprice: 'Set mit Preis – Positionen ohne Preis',
+        itemprices: 'Positionen mit Preis – Set als Überschrift',
+        setonly: 'Nur Set mit Preis – Positionen ausgeblendet'
+    },
     ctp: 'Ansprechpartner festlegen',
     mfr: 'Von MFR neu abrufen',
     rq1: 'Auftragsdaten werden von MFR abgerufen.\nDer Vorgang kann bis zu 90Sek dauern.',

Fuchs/wwwroot/web/fis.inv.de.js

@@ -146,6 +146,12 @@ let $ict = {
     eis: 'Der Rechnungsentwurf konnte nicht gespeichert werden.',
     iss: 'Zwischenstand speichern.',
     p13b: 'USt -> §13b',
+    setm: 'Set-Preisanzeige',
+    setmo: {
+        setprice: 'Set mit Preis – Positionen ohne Preis',
+        itemprices: 'Positionen mit Preis – Set als Überschrift',
+        setonly: 'Nur Set mit Preis – Positionen ausgeblendet'
+    },
     ctp: 'Ansprechpartner festlegen',
     mfr: 'Von MFR neu abrufen',
     rq1: 'Auftragsdaten werden von MFR abgerufen.\nDer Vorgang kann bis zu 90Sek dauern.',
@@ -637,6 +643,9 @@ $inv.eM = (r, re, opt) => {
     if ((opt || '').split(',').includes('p13b') === true) {
         m.push({ lbl: $ict.p13b, fnc: $inv.sp13b });
     }
+    if ((opt || '').split(',').includes('setm') === true) {
+        m.push({ lbl: $ict.setm, fnc: $inv.ssetmode });
+    }
     if (booln(r, false) === true) {
         m.push({ lbl: $ict.rel, fnc: $inv.rReload });
     }
@@ -799,7 +808,7 @@ $inv.ccInv = function (ev) {  //normale rechnung
             rif.tbl.children('tbody').each($inv.bdysort);
             rif.tbl.trigger('fds.inv');  /* trigger calculations */
 
-            $inv.eM(false, true, 'iss,p13b,ctp');
+            $inv.eM(false, true, 'iss,p13b,setm,ctp');
         }, complete: () => {
             o.c.trigger('modal_close');
         }
@@ -944,7 +953,7 @@ $inv.cntInv = function (data) {  //invoice continuation
 
             rif.tbl.children('tbody').each($inv.bdysort);
             rif.tbl.trigger('fds.inv');  /* trigger calculations */
-            $inv.eM(false, true, 'iss,p13b,ctp');
+            $inv.eM(false, true, 'iss,p13b,setm,ctp');
         }, complete: () => {
             o.c.trigger('modal_close');
         }
@@ -1187,12 +1196,19 @@ $inv.invSumUpdate = function () {
     };
     let bds = tbl.children('tbody');
     bds.each((bi, bdy) => {
-        let b = $(bdy), rx = b.data() || {}, i = [], bnet = 0, itm = b.find('tr.itm'), iso = 0, ipos = 0;
+        let b = $(bdy), rx = b.data() || {}, i = [], citems = [], cset = null, bnet = 0, itm = b.find('tr.itm'), iso = 0, ipos = 0;
         b.tC('empty', itm.length < 1);
         itm.each((ti, tx) => {
 
             let rrx = $(tx).data() || {}; csms(rrx, sms, rx.Id); bnet += (rrx.net_val || 0); i.push(rrx.co);
             //console.debug('rrx %o', rrx);
+            /* backend item contract (title/desc/qty/price_net/total_net + set flags), see InvoiceSetPricing.
+               Set grouping: an item of Type 'set' is a header that claims the following items in this
+               block as its members until the next set header (mfr__items has no explicit member link). */
+            let citem = $inv.itemToContract(rrx);
+            if (citem.type === 'set' && citem.id !== '') { cset = citem.id; }
+            else if (cset !== null && (citem.id || '') !== '') { citem.setId = cset; }
+            citems.push(citem);
             if (((typeof rrx.SortOrder === 'undefined' || rrx.SortOrder === null) ? -1 : rrx.SortOrder) > -1) {
                 if (['text', 'title'].includes((rrx.Type || 'other').toLowerCase()) === false) { ipos++; }
                 rrx.SortOrder = iso;
@@ -1204,7 +1220,7 @@ $inv.invSumUpdate = function () {
         //    f: b.find('tr.isum > td.isumval'), t: fnum(bnet, $rct.cst), n: bnet
         //});
         b.find('tr.isum > td.isumval').text(fnum(bnet, $rct.cst));
-        ba.push({ Id: rx.Id, nme: rx.Name, text: rx.text, itm: i, netval: bnet });
+        ba.push({ Id: rx.Id, nme: rx.Name, text: rx.text, itm: i, items: citems, netval: bnet });
     });
     let nonempty = tbl.find('tbody:not(.empty)').length;
     bds.find('tr.isum').tC('hidden', nonempty < 2);
@@ -1379,6 +1395,53 @@ $inv.sp13b = () => {
     }
     tbl.trigger('fds.inv');
 };
+/* Maps an item row's data to the backend item contract consumed by InvoiceSetPricing
+   / FuchsPdf.ApplyInvoice: { id, type, title (plain), desc (html), qty, price_net,
+   total_net, vat }. Set membership (type:'set' header + setId on members) is added by
+   the caller. The invoice total comes from the registration balance, so per-item
+   totals here are purely presentational. */
+$inv.itemToContract = function (rrx) {
+    rrx = rrx || {};
+    let oHtml = (e) => $$.d().append(e).html();
+    let type = (rrx.Type || '').toString().toLowerCase();
+    let ci = { id: (rrx.Id || '').toString(), type: type, title: '', desc: '', qty: '', price_net: '', total_net: (rrx.net_val || 0), vat: rrx.vat || '' };
+    if (rrx.co && rrx.co.typ === 'osum') {
+        /* combined single-sum line — the on-screen "title" is an HTML sub-table; render it as desc */
+        ci.desc = rrx.co.t || '';
+        ci.total_net = (rrx.net_val || 0);
+    } else if (['text', 'title'].includes(type) && (rrx.net_val || 0) === 0) {
+        /* heading / free-text line, no price */
+        ci.desc = rrx.htmltext || ((((rrx.NameOrNumber || '').substr(0, 1) !== '#') ? oHtml($$[0]('p').text(rrx.NameOrNumber || '')) : '') + (rrx.Note || ''));
+        ci.total_net = '';
+    } else {
+        /* normal priced item (incl. set headers, which carry their own set price or 0) */
+        ci.title = rrx.NameOrNumber || '';
+        ci.desc = rrx.Note || '';
+        ci.qty = rrx.quantity || ((rrx.quantityhours || 0) !== 0 ? (fnum(rrx.quantityhours) + (rrx.UnitString ? ' ' + rrx.UnitString : '')) : '');
+        ci.price_net = (rrx.net || 0);
+        ci.total_net = (rrx.net_val || 0);
+    }
+    return ci;
+};
+/* 3-way set-pricing display switch. Mirrors §13b: writes the choice onto admin.setmode,
+   which BuildInvoiceParams turns into the "setmode:<mode>" InvoiceOptions token the PDF reads. */
+$inv.ssetmode = () => {
+    let l = $('div.invoice_layout'), tbl = l.find('table.invi'), d = tbl.data();
+    d.admin = d.admin || {};
+    let cur = (d.admin.setmode || 'setprice'), o;
+    let btn = (mode) => $$.dc('btn', $ict.setmo[mode]).tC('selected', cur === mode).click(() => { o.c.trigger('modal_close'); $inv.setSetmode(mode); });
+    let fr = $$.dc('choicefrm').append([btn('setprice'), btn('itemprices'), btn('setonly')]);
+    o = $ocms.dlg(fr, { width: 800 });
+};
+$inv.setSetmode = (mode) => {
+    let l = $('div.invoice_layout'), tbl = l.find('table.invi'), d = tbl.data();
+    d.admin = d.admin || {};
+    d.admin.setmode = mode;                        /* posted in admin -> BuildInvoiceParams writes setmode: into InvoiceOptions */
+    d.inv = d.inv || {};                           /* keep a local InvoiceOptions reflection in sync (cosmetic) */
+    let opts = (d.inv.InvoiceOptions || '').split(',').filter(x => x !== '' && x.indexOf('setmode:') !== 0);
+    if (mode && mode !== 'setprice') { opts.push('setmode:' + mode); }
+    d.inv.InvoiceOptions = opts.join(',');
+};
 $inv.sctp = () => {
     let flds = $invcol.ctp;
     $ocms.dlgform(flds, {
@@ -1398,12 +1461,32 @@ $inv.sctp = () => {
         }, typedvalues: true
     });
 };
+/* Normalises the editor's working model into the exact field names the C# backend
+   (FdsInvoiceData.BuildInvoiceParams) reads, then returns the `invc` payload:
+   - balances/service sums come from `sms` (ttn/ttb), exposed on `new` as total_net/total_gross;
+   - every VAT rate's net amount is exposed as new.vat_<rate>_net (the backend reads the highest);
+   - new.invoicetitle -> new.title, new.loc -> new.provisionlocation, admin.paymentterms ->
+     new.paymentterm, admin.CustomerId -> admin.customerid.
+   Originals are kept alongside; the source objects are not mutated. */
+$inv.invcPayload = function (d) {
+    d = d || {};
+    let sms = d.sms || {}, nw = $.extend({}, d.new), adm = $.extend({}, d.admin);
+    nw.total_net = sms.ttn || 0;
+    nw.total_gross = sms.ttb || 0;
+    /* VAT (rate + amount) is taken by the backend straight from the posted sms.vat map
+       (FdsInvoiceData.HighestVat), so no per-rate new.vat_* keys are needed here. */
+    nw.title = (nw.invoicetitle != null ? nw.invoicetitle : (nw.title || ''));
+    nw.provisionlocation = (nw.loc != null ? nw.loc : (nw.provisionlocation || ''));
+    nw.paymentterm = (adm.paymentterms != null ? adm.paymentterms : (nw.paymentterm || ''));
+    adm.customerid = (adm.customerid != null ? adm.customerid : adm.CustomerId);
+    return { admin: adm, req: d.bai, sms: d.sms, new: nw };
+};
 $inv.ssave = () => {
     var l = $('div.invoice_layout'), d = l.find('table.invi').data();
     $inv.t_fds_inv();
     l.aC('freeze');
     $ocms.postXT({
-        url: $ocms.url('req/save'), data: { invc: JSON.stringify({ admin: d.admin, req: d.bai, sms: d.sms, new: d.new }), id: d.invid || '' }, success: (response) => {
+        url: $ocms.url('req/save'), data: { invc: JSON.stringify($inv.invcPayload(d)), id: d.invid || '' }, success: (response) => {
             $inv.cntInv({ id: response.id });
         }, error: () => {
             alert($ict.eis);
@@ -1425,7 +1508,7 @@ $inv.sprev = (change) => {
         }
     }
     $ocms.postXT({
-        url: $ocms.url('req/' + (change === true ?'sedit':'sprep')), data: { invc: JSON.stringify({ admin: d.admin, req: d.bai, sms: d.sms, new: d.new }), id: d.invid ||'' }, success: (response) => {
+        url: $ocms.url('req/' + (change === true ?'sedit':'sprep')), data: { invc: JSON.stringify($inv.invcPayload(d)), id: d.invid ||'' }, success: (response) => {
             l.rC('freeze');
             let c = $$.dc('imagecollection pdfpreview'), vhr = Math.round(vh() * 0.88), invid = response.id, invtp = response.total;
             if (invtp > 10) {

Fuchs/wwwroot/web/fis.req.de.js

@@ -146,6 +146,12 @@ let $ict = {
     eis: 'Der Rechnungsentwurf konnte nicht gespeichert werden.',
     iss: 'Zwischenstand speichern.',
     p13b: 'USt -> §13b',
+    setm: 'Set-Preisanzeige',
+    setmo: {
+        setprice: 'Set mit Preis – Positionen ohne Preis',
+        itemprices: 'Positionen mit Preis – Set als Überschrift',
+        setonly: 'Nur Set mit Preis – Positionen ausgeblendet'
+    },
     ctp: 'Ansprechpartner festlegen',
     mfr: 'Von MFR neu abrufen',
     rq1: 'Auftragsdaten werden von MFR abgerufen.\nDer Vorgang kann bis zu 90Sek dauern.',
@@ -618,6 +624,9 @@ $inv.eM = (r, re, opt) => {
     if ((opt || '').split(',').includes('p13b') === true) {
         m.push({ lbl: $ict.p13b, fnc: $inv.sp13b });
     }
+    if ((opt || '').split(',').includes('setm') === true) {
+        m.push({ lbl: $ict.setm, fnc: $inv.ssetmode });
+    }
     if (booln(r, false) === true) {
         m.push({ lbl: $ict.rel, fnc: $inv.rReload });
     }
@@ -780,7 +789,7 @@ $inv.ccInv = function (ev) {  //normale rechnung
             rif.tbl.children('tbody').each($inv.bdysort);
             rif.tbl.trigger('fds.inv');  /* trigger calculations */
 
-            $inv.eM(false, true, 'iss,p13b,ctp');
+            $inv.eM(false, true, 'iss,p13b,setm,ctp');
         }, complete: () => {
             o.c.trigger('modal_close');
         }
@@ -925,7 +934,7 @@ $inv.cntInv = function (data) {  //invoice continuation
 
             rif.tbl.children('tbody').each($inv.bdysort);
             rif.tbl.trigger('fds.inv');  /* trigger calculations */
-            $inv.eM(false, true, 'iss,p13b,ctp');
+            $inv.eM(false, true, 'iss,p13b,setm,ctp');
         }, complete: () => {
             o.c.trigger('modal_close');
         }
@@ -1168,12 +1177,19 @@ $inv.invSumUpdate = function () {
     };
     let bds = tbl.children('tbody');
     bds.each((bi, bdy) => {
-        let b = $(bdy), rx = b.data() || {}, i = [], bnet = 0, itm = b.find('tr.itm'), iso = 0, ipos = 0;
+        let b = $(bdy), rx = b.data() || {}, i = [], citems = [], cset = null, bnet = 0, itm = b.find('tr.itm'), iso = 0, ipos = 0;
         b.tC('empty', itm.length < 1);
         itm.each((ti, tx) => {
 
             let rrx = $(tx).data() || {}; csms(rrx, sms, rx.Id); bnet += (rrx.net_val || 0); i.push(rrx.co);
             //console.debug('rrx %o', rrx);
+            /* backend item contract (title/desc/qty/price_net/total_net + set flags), see InvoiceSetPricing.
+               Set grouping: an item of Type 'set' is a header that claims the following items in this
+               block as its members until the next set header (mfr__items has no explicit member link). */
+            let citem = $inv.itemToContract(rrx);
+            if (citem.type === 'set' && citem.id !== '') { cset = citem.id; }
+            else if (cset !== null && (citem.id || '') !== '') { citem.setId = cset; }
+            citems.push(citem);
             if (((typeof rrx.SortOrder === 'undefined' || rrx.SortOrder === null) ? -1 : rrx.SortOrder) > -1) {
                 if (['text', 'title'].includes((rrx.Type || 'other').toLowerCase()) === false) { ipos++; }
                 rrx.SortOrder = iso;
@@ -1185,7 +1201,7 @@ $inv.invSumUpdate = function () {
         //    f: b.find('tr.isum > td.isumval'), t: fnum(bnet, $rct.cst), n: bnet
         //});
         b.find('tr.isum > td.isumval').text(fnum(bnet, $rct.cst));
-        ba.push({ Id: rx.Id, nme: rx.Name, text: rx.text, itm: i, netval: bnet });
+        ba.push({ Id: rx.Id, nme: rx.Name, text: rx.text, itm: i, items: citems, netval: bnet });
     });
     let nonempty = tbl.find('tbody:not(.empty)').length;
     bds.find('tr.isum').tC('hidden', nonempty < 2);
@@ -1360,6 +1376,53 @@ $inv.sp13b = () => {
     }
     tbl.trigger('fds.inv');
 };
+/* Maps an item row's data to the backend item contract consumed by InvoiceSetPricing
+   / FuchsPdf.ApplyInvoice: { id, type, title (plain), desc (html), qty, price_net,
+   total_net, vat }. Set membership (type:'set' header + setId on members) is added by
+   the caller. The invoice total comes from the registration balance, so per-item
+   totals here are purely presentational. */
+$inv.itemToContract = function (rrx) {
+    rrx = rrx || {};
+    let oHtml = (e) => $$.d().append(e).html();
+    let type = (rrx.Type || '').toString().toLowerCase();
+    let ci = { id: (rrx.Id || '').toString(), type: type, title: '', desc: '', qty: '', price_net: '', total_net: (rrx.net_val || 0), vat: rrx.vat || '' };
+    if (rrx.co && rrx.co.typ === 'osum') {
+        /* combined single-sum line — the on-screen "title" is an HTML sub-table; render it as desc */
+        ci.desc = rrx.co.t || '';
+        ci.total_net = (rrx.net_val || 0);
+    } else if (['text', 'title'].includes(type) && (rrx.net_val || 0) === 0) {
+        /* heading / free-text line, no price */
+        ci.desc = rrx.htmltext || ((((rrx.NameOrNumber || '').substr(0, 1) !== '#') ? oHtml($$[0]('p').text(rrx.NameOrNumber || '')) : '') + (rrx.Note || ''));
+        ci.total_net = '';
+    } else {
+        /* normal priced item (incl. set headers, which carry their own set price or 0) */
+        ci.title = rrx.NameOrNumber || '';
+        ci.desc = rrx.Note || '';
+        ci.qty = rrx.quantity || ((rrx.quantityhours || 0) !== 0 ? (fnum(rrx.quantityhours) + (rrx.UnitString ? ' ' + rrx.UnitString : '')) : '');
+        ci.price_net = (rrx.net || 0);
+        ci.total_net = (rrx.net_val || 0);
+    }
+    return ci;
+};
+/* 3-way set-pricing display switch. Mirrors §13b: writes the choice onto admin.setmode,
+   which BuildInvoiceParams turns into the "setmode:<mode>" InvoiceOptions token the PDF reads. */
+$inv.ssetmode = () => {
+    let l = $('div.invoice_layout'), tbl = l.find('table.invi'), d = tbl.data();
+    d.admin = d.admin || {};
+    let cur = (d.admin.setmode || 'setprice'), o;
+    let btn = (mode) => $$.dc('btn', $ict.setmo[mode]).tC('selected', cur === mode).click(() => { o.c.trigger('modal_close'); $inv.setSetmode(mode); });
+    let fr = $$.dc('choicefrm').append([btn('setprice'), btn('itemprices'), btn('setonly')]);
+    o = $ocms.dlg(fr, { width: 800 });
+};
+$inv.setSetmode = (mode) => {
+    let l = $('div.invoice_layout'), tbl = l.find('table.invi'), d = tbl.data();
+    d.admin = d.admin || {};
+    d.admin.setmode = mode;                        /* posted in admin -> BuildInvoiceParams writes setmode: into InvoiceOptions */
+    d.inv = d.inv || {};                           /* keep a local InvoiceOptions reflection in sync (cosmetic) */
+    let opts = (d.inv.InvoiceOptions || '').split(',').filter(x => x !== '' && x.indexOf('setmode:') !== 0);
+    if (mode && mode !== 'setprice') { opts.push('setmode:' + mode); }
+    d.inv.InvoiceOptions = opts.join(',');
+};
 $inv.sctp = () => {
     let flds = $invcol.ctp;
     $ocms.dlgform(flds, {
@@ -1379,12 +1442,32 @@ $inv.sctp = () => {
         }, typedvalues: true
     });
 };
+/* Normalises the editor's working model into the exact field names the C# backend
+   (FdsInvoiceData.BuildInvoiceParams) reads, then returns the `invc` payload:
+   - balances/service sums come from `sms` (ttn/ttb), exposed on `new` as total_net/total_gross;
+   - every VAT rate's net amount is exposed as new.vat_<rate>_net (the backend reads the highest);
+   - new.invoicetitle -> new.title, new.loc -> new.provisionlocation, admin.paymentterms ->
+     new.paymentterm, admin.CustomerId -> admin.customerid.
+   Originals are kept alongside; the source objects are not mutated. */
+$inv.invcPayload = function (d) {
+    d = d || {};
+    let sms = d.sms || {}, nw = $.extend({}, d.new), adm = $.extend({}, d.admin);
+    nw.total_net = sms.ttn || 0;
+    nw.total_gross = sms.ttb || 0;
+    /* VAT (rate + amount) is taken by the backend straight from the posted sms.vat map
+       (FdsInvoiceData.HighestVat), so no per-rate new.vat_* keys are needed here. */
+    nw.title = (nw.invoicetitle != null ? nw.invoicetitle : (nw.title || ''));
+    nw.provisionlocation = (nw.loc != null ? nw.loc : (nw.provisionlocation || ''));
+    nw.paymentterm = (adm.paymentterms != null ? adm.paymentterms : (nw.paymentterm || ''));
+    adm.customerid = (adm.customerid != null ? adm.customerid : adm.CustomerId);
+    return { admin: adm, req: d.bai, sms: d.sms, new: nw };
+};
 $inv.ssave = () => {
     var l = $('div.invoice_layout'), d = l.find('table.invi').data();
     $inv.t_fds_inv();
     l.aC('freeze');
     $ocms.postXT({
-        url: $ocms.url('req/save'), data: { invc: JSON.stringify({ admin: d.admin, req: d.bai, sms: d.sms, new: d.new }), id: d.invid || '' }, success: (response) => {
+        url: $ocms.url('req/save'), data: { invc: JSON.stringify($inv.invcPayload(d)), id: d.invid || '' }, success: (response) => {
             $inv.cntInv({ id: response.id });
         }, error: () => {
             alert($ict.eis);
@@ -1406,7 +1489,7 @@ $inv.sprev = (change) => {
         }
     }
     $ocms.postXT({
-        url: $ocms.url('req/' + (change === true ?'sedit':'sprep')), data: { invc: JSON.stringify({ admin: d.admin, req: d.bai, sms: d.sms, new: d.new }), id: d.invid ||'' }, success: (response) => {
+        url: $ocms.url('req/' + (change === true ?'sedit':'sprep')), data: { invc: JSON.stringify($inv.invcPayload(d)), id: d.invid ||'' }, success: (response) => {
             l.rC('freeze');
             let c = $$.dc('imagecollection pdfpreview'), vhr = Math.round(vh() * 0.88), invid = response.id, invtp = response.total;
             if (invtp > 10) {