1 files changed, 114 insertions, 0 deletions
diff --git a/src/SMAPI.Mods.ErrorHandler/Patches/GameLocationPatches.cs b/src/SMAPI.Mods.ErrorHandler/Patches/GameLocationPatches.cs
new file mode 100644
index 00000000..c10f2de7
--- /dev/null
+++ b/src/SMAPI.Mods.ErrorHandler/Patches/GameLocationPatches.cs
@@ -0,0 +1,114 @@
+using System.Diagnostics.CodeAnalysis;
+#if HARMONY_2
+using System;
+using HarmonyLib;
+#else
+using System.Reflection;
+using Harmony;
+#endif
+using StardewModdingAPI.Framework.Patching;
+using StardewValley;
+
+namespace StardewModdingAPI.Mods.ErrorHandler.Patches
+{
+    /// <summary>A Harmony patch for <see cref="GameLocation.checkEventPrecondition"/> which intercepts invalid preconditions and logs an error instead of crashing.</summary>
+    /// <remarks>Patch methods must be static for Harmony to work correctly. See the Harmony documentation before renaming patch arguments.</remarks>
+    [SuppressMessage("ReSharper", "InconsistentNaming", Justification = "Argument names are defined by Harmony and methods are named for clarity.")]
+    [SuppressMessage("ReSharper", "IdentifierTypo", Justification = "Argument names are defined by Harmony and methods are named for clarity.")]
+    internal class GameLocationPatches : IHarmonyPatch
+    {
+        /*********
+        ** Fields
+        *********/
+        /// <summary>Writes messages to the console and log file on behalf of the game.</summary>
+        private static IMonitor MonitorForGame;
+
+
+        /*********
+        ** Accessors
+        *********/
+        /// <inheritdoc />
+        public string Name => nameof(GameLocationPatches);
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="monitorForGame">Writes messages to the console and log file on behalf of the game.</param>
+        public GameLocationPatches(IMonitor monitorForGame)
+        {
+            GameLocationPatches.MonitorForGame = monitorForGame;
+        }
+
+        /// <inheritdoc />
+#if HARMONY_2
+        public void Apply(Harmony harmony)
+        {
+            harmony.Patch(
+                original: AccessTools.Method(typeof(GameLocation), "checkEventPrecondition"),
+                finalizer: new HarmonyMethod(this.GetType(), nameof(EventErrorPatch.Finalize_GameLocation_CheckEventPrecondition))
+            );
+        }
+#else
+        public void Apply(HarmonyInstance harmony)
+        {
+            harmony.Patch(
+                original: AccessTools.Method(typeof(GameLocation), "checkEventPrecondition"),
+                prefix: new HarmonyMethod(this.GetType(), nameof(GameLocationPatches.Before_GameLocation_CheckEventPrecondition))
+            );
+        }
+#endif
+
+
+        /*********
+        ** Private methods
+        *********/
+#if HARMONY_2
+        /// <summary>The method to call instead of GameLocation.checkEventPrecondition.</summary>
+        /// <param name="__result">The return value of the original method.</param>
+        /// <param name="precondition">The precondition to be parsed.</param>
+        /// <param name="__exception">The exception thrown by the wrapped method, if any.</param>
+        /// <returns>Returns the exception to throw, if any.</returns>
+        private static Exception Finalize_GameLocation_CheckEventPrecondition(ref int __result, string precondition, Exception __exception)
+        {
+            if (__exception != null)
+            {
+                __result = -1;
+                EventErrorPatch.MonitorForGame.Log($"Failed parsing event precondition ({precondition}):\n{__exception.InnerException}", LogLevel.Error);
+            }
+
+            return null;
+        }
+#else
+        /// <summary>The method to call instead of GameLocation.checkEventPrecondition.</summary>
+        /// <param name="__instance">The instance being patched.</param>
+        /// <param name="__result">The return value of the original method.</param>
+        /// <param name="precondition">The precondition to be parsed.</param>
+        /// <param name="__originalMethod">The method being wrapped.</param>
+        /// <returns>Returns whether to execute the original method.</returns>
+        private static bool Before_GameLocation_CheckEventPrecondition(GameLocation __instance, ref int __result, string precondition, MethodInfo __originalMethod)
+        {
+            const string key = nameof(GameLocationPatches.Before_GameLocation_CheckEventPrecondition);
+            if (!PatchHelper.StartIntercept(key))
+                return true;
+
+            try
+            {
+                __result = (int)__originalMethod.Invoke(__instance, new object[] { precondition });
+                return false;
+            }
+            catch (TargetInvocationException ex)
+            {
+                __result = -1;
+                GameLocationPatches.MonitorForGame.Log($"Failed parsing event precondition ({precondition}):\n{ex.InnerException}", LogLevel.Error);
+                return false;
+            }
+            finally
+            {
+                PatchHelper.StopIntercept(key);
+            }
+        }
+#endif
+    }
+}