Prefab patching

Editor/PrefabPatchPlayModeCleanup.cs

@@ -0,0 +1,20 @@
+using PatchManager.PrefabPatching;
+using UnityEditor;
+
+namespace PatchManager.Editor;
+
+[InitializeOnLoad]
+internal static class PrefabPatchPlayModeCleanup
+{
+    static PrefabPatchPlayModeCleanup()
+    {
+        EditorApplication.playModeStateChanged -= OnPlayModeStateChanged;
+        EditorApplication.playModeStateChanged += OnPlayModeStateChanged;
+    }
+
+    private static void OnPlayModeStateChanged(PlayModeStateChange state)
+    {
+        if (state == PlayModeStateChange.ExitingPlayMode)
+            PrefabPatchRuntime.ReleaseSessionResources();
+    }
+}

README.md

@@ -1,4 +1,4 @@
 # Patch Manager
 A mod for generic patching needs similar to KSP 1's Module Manager.
 
-Documentation: https://ksp2community.github.io/PatchManagerDocs/
+Documentation: https://modding.ksp2redux.org

Runtime/CSharpPatching/PrefabPatchingCSharpPatching.cs

@@ -0,0 +1,24 @@
+using PatchManager.PrefabPatching;
+
+namespace PatchManager.CSharpPatching
+{
+    /// <summary>
+    /// Mod-scoped C# frontend for declarative prefab patches.
+    /// </summary>
+    public static class PrefabPatchingCSharpPatching
+    {
+        /// <summary>
+        /// Creates a prefab patch owned by the calling mod's swinfo identity.
+        /// </summary>
+        /// <summary>
+        /// Creates a prefab patch targeting a stock Addressables key.
+        /// Canonical bundle and CAB metadata are not part of imperative
+        /// authoring.
+        /// </summary>
+        public static PrefabPatchBuilder PatchPrefab(
+            this PmScope scope,
+            string name,
+            string address
+        ) => new(scope.ModId, name, address);
+    }
+}

Runtime/Core/Assets/Locators.cs

@@ -38,15 +38,33 @@ public static void Register(IResourceLocator locator)
         /// <param name="locations">List of locations of the found assets.</param>
         /// <returns>True if any assets were found, false otherwise.</returns>
         public static bool LocateAll(object label, out List<IResourceLocation> locations)
+        {
+            return LocateAll(label, typeof(TextAsset), out locations);
+        }
+
+        /// <summary>
+        /// Locate assets by key and requested type across every Patch Manager
+        /// asset-domain locator.
+        /// </summary>
+        public static bool LocateAll(
+            object key,
+            System.Type type,
+            out List<IResourceLocation> locations
+        )
         {
             locations = new List<IResourceLocation>();
             foreach (var locator in ResourceLocators)
             {
-                locator.Locate(label, typeof(TextAsset), out var foundLocations);
-                locations.AddRange(foundLocations);
+                if (
+                    locator.Locate(key, type, out var foundLocations)
+                    && foundLocations != null
+                )
+                {
+                    locations.AddRange(foundLocations);
+                }
             }
 
             return locations.Count > 0;
         }
     }
-}
+}

Runtime/Core/Cache/CacheManager.cs

@@ -3,6 +3,7 @@
 using System.IO;
 using System.Reflection;
 using PatchManager.Core.Cache.Json;
+using PatchManager.PrefabPatching;
 using PatchManager.Shared;
 
 namespace PatchManager.Core.Cache
@@ -200,7 +201,7 @@ public static void SaveInventory()
 
         public static void SaveSummary(Summary universeSummary)
         {
-            File.WriteAllText("./pm_summary.log", universeSummary.Dump());
+            PatchManagerSummaryLog.UpdateCoreSummary(universeSummary.Dump());
         }
     }
 }

Runtime/Core/CoreModule.cs

@@ -1,15 +1,18 @@
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using JetBrains.Annotations;
 using KSP.Game;
 using KSP.Game.Flow;
 using PatchManager.Core.Assets;
 using PatchManager.Core.Cache;
 using PatchManager.LuaPatching;
+using PatchManager.PrefabPatching;
 using PatchManager.Shared;
 using PatchManager.Shared.Modules;
 using ReduxLib.Configuration;
 using ReduxLib.Configuration.Attributes;
+using SpaceWarp2.API.Mods;
 using UnityEngine;
 using UnityEngine.AddressableAssets;
 using UnityEngine.UIElements;
@@ -81,6 +84,12 @@ private void DecideCacheValidity(Action resolve, Action<string> reject)
                 tail.Add(new GenericFlowAction("Patch Manager: Saving Patch Summary", SavePatchSummary));
             }
 
+            tail.Add(
+                new GenericFlowAction(
+                    "Patch Manager: Resolving Prefab Patch Plans",
+                    ResolvePrefabPatchPlans
+                )
+            );
             tail.Add(new GenericFlowAction("Patch Manager: Registering Resource Locator", RegisterResourceLocator));
 
             // Splice the tail in right after this step. Insert back-to-front so each Insert at the same index
@@ -97,9 +106,39 @@ private void DecideCacheValidity(Action resolve, Action<string> reject)
         private static void CloseRegistration(Action resolve, Action<string> reject)
         {
             PatchingManager.Universe.RegistrationOpen = false;
+            PrefabPatchRuntime.CloseRegistration();
             resolve();
         }
 
+        private static void ResolvePrefabPatchPlans(
+            Action resolve,
+            Action<string> reject
+        )
+        {
+            var manifestSources =
+                PluginList.AllEnabledAndActivePlugins
+                    .Where(descriptor =>
+                        !string.IsNullOrWhiteSpace(
+                            descriptor.AddressablePrefabPatchLabel
+                        )
+                    )
+                    .Select(descriptor =>
+                        new PrefabPatchManifestSource
+                        {
+                            OwnerModId = descriptor.Guid,
+                            AddressablesLabel =
+                                descriptor.AddressablePrefabPatchLabel
+                        }
+                    )
+                    .ToArray();
+            PrefabPatchRuntime.DiscoverAndResolve(
+                PatchingManager.Universe.AllMods,
+                manifestSources,
+                resolve,
+                reject
+            );
+        }
+
         private void SavePatchSummary(Action resolve, Action<string> reject)
         {
             PatchingManager.Universe.Summary.RecognizedModIds = PatchingManager.Universe.AllMods;
@@ -146,6 +185,7 @@ private void RegisterResourceLocator(Action resolve, Action<string> reject)
             }
 
             Locators.Register(new ArchiveResourceLocator());
+            Locators.Register(PrefabPatchRuntime.RegisterResourceProvider());
             GameManager.Instance.Game.UI.UitkLoadingCurtain.Data.PatchManagerDefinitionsModifiedCount =
                 CacheManager.Inventory.DefinitionCount;
             GameManager.Instance.Game.UI.UitkLoadingCurtain.Data.PatchManagerNewAssetCount =
@@ -189,6 +229,15 @@ public override VisualElement GetDetails()
                 text.text += $"\n- {label}";
             }
 
+            var prefabMetrics = PrefabPatchRuntime.CurrentMetrics;
+            text.text +=
+                $"\nPrefab plans: {prefabMetrics.ResolvedPlanCount}"
+                + $" ({prefabMetrics.CacheHitCount} cache hit(s), "
+                + $"{prefabMetrics.CacheMissCount} miss(es))";
+            text.text +=
+                $"\nRetained prefab handles: "
+                + $"{prefabMetrics.RetainedAddressablesHandles}";
+
             text.visible = true;
             text.style.display = DisplayStyle.Flex;
             foldout.Add(text);

Runtime/LuaPatching/Builtin/PatchManagerCore.cs

@@ -85,6 +85,44 @@ public PatchDefinition Patch(ScriptExecutionContext context, string converter, s
         return newPatch;
     }
 
+    /// <summary>
+    /// Begins a declarative prefab patch for one stock Addressables key.
+    /// </summary>
+    public PrefabPatchLuaBuilder Prefab(
+        ScriptExecutionContext context,
+        string name,
+        DynValue target
+    )
+    {
+        if (!_universe.RegistrationOpen)
+        {
+            throw new ScriptRuntimeException(
+                $"PM:Prefab('{name}') can only be called during patch "
+                    + "registration."
+            );
+        }
+
+        var modId = context.CurrentGlobalEnv
+            .Get("ModId")
+            .CastToString();
+        if (target.Type != DataType.String)
+        {
+            throw new ScriptRuntimeException(
+                "PM:Prefab expects the stock prefab's Addressables key."
+            );
+        }
+        var identity =
+            global::PatchManager.PrefabPatching.PrefabPatchPrefabIdentity
+                .FromAddress(target.String);
+        return new PrefabPatchLuaBuilder(
+            new global::PatchManager.PrefabPatching.PrefabPatchBuilder(
+                modId,
+                name,
+                identity
+            )
+        );
+    }
+
     /// <summary>
     /// Queues a brand-new asset for creation under the given label and address.
     /// </summary>