object validation as per openloco

Core/DatFileParsing/SawyerStreamReader.cs

@@ -12,15 +12,18 @@ namespace OpenLoco.ObjectEditor.DatFileParsing
 {
 	public static class SawyerStreamReader
 	{
-		public static List<S5Header> LoadVariableCountS5Headers(ReadOnlySpan<byte> data, int count)
+		public static List<S5Header> LoadVariableCountS5Headers(ReadOnlySpan<byte> data, int max)
 		{
 			List<S5Header> result = [];
-			for (var i = 0; i < count; ++i)
+			for (var i = 0; i < max; ++i)
 			{
-				var header = S5Header.Read(data[..S5Header.StructLength]);
-				if (header.Checksum != 0 || header.Flags != 255)
+				if (data[0] != 0xFF)
 				{
-					result.Add(header);
+					var header = S5Header.Read(data[..S5Header.StructLength]);
+					if (header.Checksum != 0 || header.Flags != 255)
+					{
+						result.Add(header);
+					}
 				}
 
 				data = data[S5Header.StructLength..];
@@ -148,12 +151,33 @@ public static (DatFileInfo DatFileInfo, ILocoObject? LocoObject) LoadFullObjectF
 				locoStructPostLoad.PostLoad();
 			}
 
+			ValidateLocoStruct(s5Header, locoStruct, logger);
+
 			// add to object manager
 			SObjectManager.Add(newObj);
 
 			return new(new DatFileInfo(s5Header, objectHeader), newObj);
 		}
 
+		static void ValidateLocoStruct(S5Header s5Header, ILocoStruct locoStruct, ILogger? logger)
+		{
+			try
+			{
+				if (!locoStruct.Validate())
+				{
+					logger?.Warning($"\"{s5Header.Name}\" failed validation");
+				}
+				else
+				{
+					logger?.Info($"\"{s5Header.Name}\" validated successfully");
+				}
+			}
+			catch (NotImplementedException)
+			{
+				logger?.Debug2($"{s5Header.ObjectType} object type is missing validation function");
+			}
+		}
+
 		static string CStringToString(ReadOnlySpan<byte> data, Encoding enc)
 		{
 			var ptr = 0;

Core/Objects/Airport/AirportObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
@@ -164,5 +164,20 @@ public ReadOnlySpan<byte> Save()
 
 			return ms.ToArray();
 		}
+
+		public bool Validate()
+		{
+			if (CostIndex > 32)
+			{
+				return false;
+			}
+
+			if (-SellCostFactor > BuildCostFactor)
+			{
+				return false;
+			}
+
+			return BuildCostFactor > 0;
+		}
 	}
 }

Core/Objects/Airport/MovementEdge.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
 namespace Core.Objects
@@ -12,5 +12,8 @@ public record MovementEdge(
 		[property: LocoStructOffset(0x03)] uint8_t var_03,
 		[property: LocoStructOffset(0x04)] uint32_t MustBeClearEdges,    // Which edges must be clear to use the transition edge. should probably be some kind of flags?
 		[property: LocoStructOffset(0x08)] uint32_t AtLeastOneClearEdges // Which edges must have at least one clear to use transition edge. should probably be some kind of flags?
-		) : ILocoStruct;
+		) : ILocoStruct
+	{
+		public bool Validate() => true;
+	}
 }

Core/Objects/Airport/MovementNode.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
 namespace Core.Objects
@@ -10,5 +10,8 @@ public record MovementNode(
 		[property: LocoStructOffset(0x02)] int16_t Y,
 		[property: LocoStructOffset(0x04)] int16_t Z,
 		[property: LocoStructOffset(0x06)] AirportMovementNodeFlags Flags
-		) : ILocoStruct;
+		) : ILocoStruct
+	{
+		public bool Validate() => true;
+	}
 }

Core/Objects/BridgeObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 using OpenLoco.ObjectEditor.Headers;
@@ -61,5 +61,39 @@ public ReadOnlySpan<byte> Save()
 
 			return headers.SelectMany(h => h.Write().ToArray()).ToArray();
 		}
+
+		public bool Validate()
+		{
+			if (CostIndex > 32)
+			{
+				return false;
+			}
+
+			if (-SellCostFactor > BaseCostFactor)
+			{
+				return false;
+			}
+			if (BaseCostFactor <= 0)
+			{
+				return false;
+			}
+			if (HeightCostFactor < 0)
+			{
+				return false;
+			}
+			if (var_06 != 16 && var_06 != 32)
+			{
+				return false;
+			}
+			if (SpanLength != 1 && SpanLength != 2 && SpanLength != 4)
+			{
+				return false;
+			}
+			if (NumCompatibleTrackMods > 7)
+			{
+				return false;
+			}
+			return NumCompatibleRoadMods <= 7;
+		}
 	}
-}
+}

Core/Objects/BuildingObject.cs

@@ -141,13 +141,13 @@
 			// produced cargo
 			foreach (var obj in ProducedCargo.Fill(MaxProducedCargoType, S5Header.NullHeader))
 			{
 				ms.Write(obj.Write());
 			}
 
 			// required cargo
 			foreach (var obj in RequiredCargo.Fill(MaxRequiredCargoType, S5Header.NullHeader))
 			{
 				ms.Write(obj.Write());
 			}
 
 			foreach (var unk in ElevatorAnimationHeights)
@@ -161,5 +161,9 @@
 
 			return ms.ToArray();
 		}
+
+		public bool Validate()
+			=> NumAnimations is not 0 and not > 63
+			&& NumVariations is not 0 and <= 31;
 	}
 }

Core/Objects/CargoObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
@@ -53,5 +53,10 @@ public record CargoObject(
 		[property: LocoStructOffset(0x1B)] uint16_t PaymentFactor,
 		[property: LocoStructOffset(0x1D)] uint8_t PaymentIndex,
 		[property: LocoStructOffset(0x1E)] uint8_t UnitSize
-	) : ILocoStruct;
-}
+		) : ILocoStruct
+	{
+		public bool Validate()
+			=> var_02 <= 3840
+			&& CargoTransferTime != 0;
+	}
+}

Core/Objects/CliffEdgeObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
@@ -11,5 +11,8 @@ namespace OpenLoco.ObjectEditor.Objects
 	public record CliffEdgeObject(
 		[property: LocoStructOffset(0x00), LocoString, Browsable(false)] string_id Name,
 		[property: LocoStructOffset(0x02), LocoString, Browsable(false)] image_id Image
-		) : ILocoStruct;
+		) : ILocoStruct
+	{
+		public bool Validate() => true;
+	}
 }

Core/Objects/ClimateObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
@@ -18,5 +18,9 @@ public record ClimateObject(
 		) : ILocoStruct
 	{
 		public const int Seasons = 4;
+
+		public bool Validate()
+			=> WinterSnowLine <= SummerSnowLine
+			&& FirstSeason < 4;
 	}
 }

Core/Objects/CompetitorObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
@@ -13,7 +13,7 @@ public record CompetitorObject(
 			[property: LocoStructOffset(0x00), LocoString, Browsable(false)] string_id LastName,
 			[property: LocoStructOffset(0x04)] uint32_t var_04,
 			[property: LocoStructOffset(0x08)] uint32_t var_08,
-			[property: LocoStructOffset(0x0C)] uint8_t Emotions,
+			[property: LocoStructOffset(0x0C)] uint32_t Emotions,
 			[property: LocoStructOffset(0x10), Browsable(false), LocoArrayLength(CompetitorObject.ImagesLength)] image_id[] Images,
 			[property: LocoStructOffset(0x34)] uint8_t Intelligence,
 			[property: LocoStructOffset(0x35)] uint8_t Aggressiveness,
@@ -22,5 +22,22 @@ public record CompetitorObject(
 		) : ILocoStruct
 	{
 		public const int ImagesLength = 9;
+
+		public bool Validate()
+		{
+			if ((Emotions & (1 << 0)) == 0)
+			{
+				return false;
+			}
+			if (Intelligence < 1 || Intelligence > 9)
+			{
+				return false;
+			}
+			if (Aggressiveness < 1 || Aggressiveness > 9)
+			{
+				return false;
+			}
+			return Competitiveness >= 1 && Competitiveness <= 9;
+		}
 	}
 }

Core/Objects/CurrencyObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
@@ -15,5 +15,19 @@ public record CurrencyObject(
 		[property: LocoStructOffset(0x06), Browsable(false)] image_id ObjectIcon,
 		[property: LocoStructOffset(0x0A)] uint8_t Separator,
 		[property: LocoStructOffset(0x0B)] uint8_t Factor
-	) : ILocoStruct;
+		) : ILocoStruct
+	{
+		public bool Validate()
+		{
+			if (Separator > 4)
+			{
+				return false;
+			}
+			if (Factor > 3)
+			{
+				return false;
+			}
+			return true;
+		}
+	}
 }

Core/Objects/DockObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 using OpenLoco.ObjectEditor.Types;
@@ -78,5 +78,19 @@ public ReadOnlySpan<byte> Save()
 			.Concat(var_1C)
 			.Concat(new byte[] { 0xFF })
 			.ToArray();
+		public bool Validate()
+		{
+			if (CostIndex > 32)
+			{
+				return false;
+			}
+
+			if (-SellCostFactor > BuildCostFactor)
+			{
+				return false;
+			}
+
+			return BuildCostFactor > 0;
+		}
 	}
 }

Core/Objects/HillShapesObject.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.Data;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
@@ -15,5 +15,8 @@ public record HillShapesObject(
 		[property: LocoStructOffset(0x04), Browsable(false)] image_id Image,
 		[property: LocoStructOffset(0x08), Browsable(false)] image_id ImageHill,
 		[property: LocoStructOffset(0x0C), LocoArrayLength(0x0E - 0x0C), Browsable(false)] uint8_t[] pad_0C
-	) : ILocoStruct;
+		) : ILocoStruct
+	{
+		public bool Validate() => true;
+	}
 }

Core/Objects/Industry/BuildingPartAnimation.cs

@@ -1,4 +1,4 @@
-using System.ComponentModel;
+using System.ComponentModel;
 using OpenLoco.ObjectEditor.DatFileParsing;
 
 namespace Core.Objects
@@ -9,5 +9,12 @@ namespace Core.Objects
 	public record BuildingPartAnimation(
 		[property: LocoStructOffset(0x00)] uint8_t NumFrames,     // Must be a power of 2 (0 = no part animation, could still have animation sequence)
 		[property: LocoStructOffset(0x01)] uint8_t AnimationSpeed // Also encodes in bit 7 if the animation is position modified
-		) : ILocoStruct;
+		) : ILocoStruct
+	{
+		public bool Validate()
+			=> IsPowerOfTwo(NumFrames);
+
+		static bool IsPowerOfTwo(uint8_t x)
+			=> (x & (x - 1)) == 0 && x > 0;
+	}
 }