Move rolling stock and physics into the domain

VehicleDatabase becomes VehicleCatalog, Physics becomes VehiclePhysics, and the
textures.txt and .fiz parsers move to Infrastructure. GameLibrary replaces the
GameData singleton.

StarterNG/Domain/Vehicles/VehicleCatalog.cs

@@ -0,0 +1,198 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using StarterNG.Application.Abstractions;
+
+namespace StarterNG.Domain.Vehicles;
+
+/// <summary>
+/// Every livery the installation offers, indexed for the lookups the depot and
+/// the consist editor make: by uuid, by skin file, and by the set a vehicle
+/// belongs to.
+/// </summary>
+/// <remarks>
+/// Was <c>VehicleCatalog</c>, which also owned file enumeration, textures.txt
+/// parsing, a static thumbnail dictionary and a missing-asset scan. Those moved
+/// to Infrastructure; what is left is the model and its resolution rules, filled
+/// by a repository through <see cref="Ingest"/>.
+/// </remarks>
+public sealed class VehicleCatalog
+{
+    private readonly IMiniTextureIndex _minis;
+
+    public VehicleCatalog(IMiniTextureIndex minis)
+    {
+        _minis = minis;
+    }
+
+    /// <summary>Every livery worth offering (wrecks excluded).</summary>
+    public List<VehicleTexture> Textures { get; } = new();
+
+    public Dictionary<string, VehicleGroup> GroupsById { get; } = new();
+
+    public List<VehicleSet> Sets { get; } = new();
+
+    public Dictionary<string, VehicleSet> SetByTextureUuid { get; } = new();
+
+    public Dictionary<string, VehicleTexture> TextureByUuid { get; } = new();
+
+    /// <summary>Liveries by skin file name without extension, lower cased.</summary>
+    public Dictionary<string, VehicleTexture> TextureBySkin { get; } = new();
+
+    public void BeginLoad()
+    {
+        Textures.Clear();
+        GroupsById.Clear();
+        Sets.Clear();
+        SetByTextureUuid.Clear();
+        TextureByUuid.Clear();
+        TextureBySkin.Clear();
+    }
+
+    /// <summary>Adds one vehicle folder's liveries to the catalogue.</summary>
+    public void Ingest(VehicleEntry entry)
+    {
+        foreach (var group in entry.Groups)
+            if (!string.IsNullOrEmpty(group.Id))
+                GroupsById.TryAdd(group.Id, group);
+
+        foreach (var texture in entry.Textures)
+        {
+            if (!string.IsNullOrEmpty(texture.Uuid))
+                TextureByUuid[texture.Uuid] = texture;
+
+            if (!string.IsNullOrEmpty(texture.Skinfile))
+                TextureBySkin.TryAdd(Path.GetFileNameWithoutExtension(texture.Skinfile).ToLowerInvariant(), texture);
+
+            if (texture.Wreck)
+                continue;
+
+            Textures.Add(texture);
+        }
+
+        Sets.AddRange(entry.Sets);
+    }
+
+    /// <summary>Builds the indexes that depend on the catalogue being complete.</summary>
+    public void EndLoad()
+    {
+        BuildSetIndex();
+        ResolveGroupInheritance();
+    }
+
+    /// <summary>The vehicles of the fixed set this livery leads or belongs to.</summary>
+    public List<VehicleTexture>? ResolveSet(VehicleTexture texture)
+    {
+        if (string.IsNullOrEmpty(texture.Uuid))
+            return null;
+        if (!SetByTextureUuid.TryGetValue(texture.Uuid, out var set) || set.TextureRefs is null)
+            return null;
+
+        var cars = new List<VehicleTexture>();
+        foreach (string uuid in set.TextureRefs)
+            if (!string.IsNullOrEmpty(uuid) && TextureByUuid.TryGetValue(uuid, out var car))
+                cars.Add(car);
+
+        return cars.Count > 0 ? cars : null;
+    }
+
+    /// <summary>
+    /// True when the livery is a non-leading member of a set, and so is added
+    /// along with its leader rather than on its own.
+    /// </summary>
+    public bool IsSetFollower(VehicleTexture texture)
+    {
+        if (string.IsNullOrEmpty(texture.Uuid))
+            return false;
+        if (!SetByTextureUuid.TryGetValue(texture.Uuid, out var set) ||
+            set.TextureRefs is null || set.TextureRefs.Count < 2)
+            return false;
+
+        string? lead = set.TextureRefs.FirstOrDefault(reference => !string.IsNullOrEmpty(reference));
+        return lead is not null && !string.Equals(lead, texture.Uuid, StringComparison.OrdinalIgnoreCase);
+    }
+
+    /// <summary>
+    /// The thumbnail to draw for a livery: its own if we have that bitmap,
+    /// otherwise the one its group declares.
+    /// </summary>
+    public string? ResolveMiniName(VehicleTexture texture)
+    {
+        if (_minis.Has(texture.TextureMini))
+            return texture.TextureMini;
+
+        if (texture.Group is not null && GroupsById.TryGetValue(texture.Group, out var group) &&
+            !string.IsNullOrEmpty(group.Mini))
+            return group.Mini;
+
+        return texture.TextureMini;
+    }
+
+    public string? MiniForSkin(string? skinFile) =>
+        TextureForSkin(skinFile) is { } texture ? ResolveMiniName(texture) : null;
+
+    public VehicleTexture? TextureForSkin(string? skinFile)
+    {
+        if (string.IsNullOrEmpty(skinFile))
+            return null;
+
+        string key = Path.GetFileNameWithoutExtension(skinFile).ToLowerInvariant();
+        return TextureBySkin.TryGetValue(key, out var texture) ? texture : null;
+    }
+
+    /// <summary>Heading shown above a group in the depot browser.</summary>
+    public string GroupHeader(string? groupId)
+    {
+        if (string.IsNullOrEmpty(groupId) || !GroupsById.TryGetValue(groupId, out var group))
+            return groupId ?? "";
+
+        string mini = string.IsNullOrEmpty(group.Mini) ? group.Id : group.Mini;
+        return string.IsNullOrEmpty(group.Category) ? mini : $"{mini}  ({group.Category})";
+    }
+
+    private void BuildSetIndex()
+    {
+        foreach (var set in Sets)
+        {
+            if (set.TextureRefs is null)
+                continue;
+
+            foreach (string uuid in set.TextureRefs)
+                if (!string.IsNullOrEmpty(uuid))
+                    SetByTextureUuid[uuid] = set;
+        }
+    }
+
+    /// <summary>
+    /// Copies thumbnail, category and archived status down from each group onto
+    /// its liveries, so the browser can sort and filter without walking back up.
+    /// </summary>
+    private void ResolveGroupInheritance()
+    {
+        foreach (var texture in Textures)
+        {
+            VehicleGroup? group = null;
+            if (texture.Group is not null)
+                GroupsById.TryGetValue(texture.Group, out group);
+
+            string mini = group is not null && !string.IsNullOrEmpty(group.Mini)
+                ? group.Mini
+                : texture.MiniRef ?? "";
+
+            string? category = group?.Category;
+
+            // "*" means "categorise by the first letter of the thumbnail name".
+            if (category == "*")
+            {
+                string source = !string.IsNullOrEmpty(mini) ? mini : texture.TextureMini ?? "";
+                if (source.Length > 0)
+                    category = char.ToUpperInvariant(source[0]).ToString();
+            }
+
+            texture.ResolvedCategory = category;
+            texture.ResolvedClass = mini;
+            texture.ResolvedArchived = group?.Archived ?? false;
+        }
+    }
+}