feat(commands): add UpkeepLine formatter (6b)

Author: HandyS11

src/RustPlusBot.Features.Commands/Formatting/UpkeepLine.cs

@@ -0,0 +1,28 @@
+using System.Globalization;
+using RustPlusBot.Features.ItemData.Data;
+using RustPlusBot.Features.ItemData.Naming;
+
+namespace RustPlusBot.Features.Commands.Formatting;
+
+/// <summary>Formats the one-line upkeep-cost reply.</summary>
+internal static class UpkeepLine
+{
+    /// <summary>Formats the per-resource upkeep cost for a building block.</summary>
+    /// <param name="item">The item (must have non-null <see cref="ItemRecord.Upkeep"/>).</param>
+    /// <param name="names">Resolves resource item ids to names.</param>
+    public static string Format(ItemRecord item, IItemNameResolver names)
+    {
+        ArgumentNullException.ThrowIfNull(item);
+        ArgumentNullException.ThrowIfNull(names);
+        ArgumentNullException.ThrowIfNull(item.Upkeep);
+
+        var parts = item.Upkeep.Entries.Select(e =>
+        {
+            var quantity = e.QuantityMin == e.QuantityMax
+                ? e.QuantityMin.ToString(CultureInfo.InvariantCulture)
+                : string.Create(CultureInfo.InvariantCulture, $"{e.QuantityMin}–{e.QuantityMax}");
+            return string.Create(CultureInfo.InvariantCulture, $"{quantity} {names.Resolve(e.ItemId)}");
+        });
+        return string.Create(CultureInfo.InvariantCulture, $"{item.Name} upkeep: {string.Join(", ", parts)}");
+    }
+}

tests/RustPlusBot.Features.Commands.Tests/Formatting/UpkeepFormatterTests.cs

@@ -0,0 +1,32 @@
+using RustPlusBot.Features.Commands.Formatting;
+using RustPlusBot.Features.ItemData;
+using RustPlusBot.Features.ItemData.Data;
+using RustPlusBot.Features.ItemData.Naming;
+
+namespace RustPlusBot.Features.Commands.Tests.Formatting;
+
+public sealed class UpkeepFormatterTests
+{
+    private readonly IItemNameResolver _names = new ItemDatabaseNameResolver(new EmbeddedItemDatabase());
+
+    [Fact]
+    public void UpkeepLine_RendersRange()
+    {
+        var item = new ItemRecord(1, "Wooden Door", 1, null, null, null, null, null,
+            new UpkeepCost([new UpkeepEntry(-151838493, 8, 25)]));
+        var line = UpkeepLine.Format(item, _names);
+        Assert.Contains("Wooden Door", line, StringComparison.Ordinal);
+        Assert.Contains("8–25", line, StringComparison.Ordinal); // 8–25
+        Assert.Contains("Wood", line, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void UpkeepLine_RendersSingleQuantityWithoutRange()
+    {
+        var item = new ItemRecord(1, "Reinforced Glass Window", 1, null, null, null, null, null,
+            new UpkeepCost([new UpkeepEntry(317398316, 1, 1)]));
+        var line = UpkeepLine.Format(item, _names);
+        Assert.DoesNotContain("–", line, StringComparison.Ordinal); // no en-dash for a single value
+        Assert.Contains("1", line, StringComparison.Ordinal);
+    }
+}