Fix bot exploration and add hostility detection

- Track unreachable NPCs to avoid infinite retries
- Clear unreachable list when changing zones
- Add name-based hostility detection for NPCs
- Check top layer tiles for walkability
- Fix MissionSolver to skip likely hostile NPCs by name patterns

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

DecompressSzdd.cs

@@ -0,0 +1,87 @@
+using System;
+using System.IO;
+
+class Program
+{
+    static void Main(string[] args)
+    {
+        if (args.Length != 2)
+        {
+            Console.WriteLine("Usage: DecompressSzdd input.DA_ output.DTA");
+            return;
+        }
+
+        DecompressSzdd(args[0], args[1]);
+    }
+
+    static void DecompressSzdd(string inputPath, string outputPath)
+    {
+        using var fs = File.OpenRead(inputPath);
+        using var reader = new BinaryReader(fs);
+
+        // Read magic "SZDD"
+        var magic = reader.ReadBytes(4);
+        if (magic[0] != 'S' || magic[1] != 'Z' || magic[2] != 'D' || magic[3] != 'D')
+        {
+            Console.WriteLine($"Not an SZDD file");
+            return;
+        }
+
+        // Read header
+        var compMode = reader.ReadByte();
+        var missingChar = reader.ReadByte();
+        reader.ReadBytes(2); // padding
+
+        var uncompressedSize = reader.ReadUInt32();
+        Console.WriteLine($"Uncompressed size: {uncompressedSize}");
+
+        // Read compressed data
+        var compressed = reader.ReadBytes((int)(fs.Length - fs.Position));
+
+        // Decompress
+        var output = new MemoryStream();
+        var ringBuffer = new byte[4096];
+        int ringPos = 4096 - 16;
+
+        int i = 0;
+        while (i < compressed.Length && output.Length < uncompressedSize)
+        {
+            byte flags = compressed[i++];
+
+            for (int bit = 0; bit < 8 && i < compressed.Length && output.Length < uncompressedSize; bit++)
+            {
+                if ((flags & (1 << bit)) != 0)
+                {
+                    // Literal byte
+                    byte b = compressed[i++];
+                    output.WriteByte(b);
+                    ringBuffer[ringPos] = b;
+                    ringPos = (ringPos + 1) & 0xFFF;
+                }
+                else
+                {
+                    // Back reference
+                    if (i + 1 >= compressed.Length) break;
+
+                    int b1 = compressed[i++];
+                    int b2 = compressed[i++];
+
+                    int offset = b1 | ((b2 & 0xF0) << 4);
+                    int length = (b2 & 0x0F) + 3;
+
+                    for (int j = 0; j < length && output.Length < uncompressedSize; j++)
+                    {
+                        byte b = ringBuffer[offset];
+                        output.WriteByte(b);
+                        ringBuffer[ringPos] = b;
+                        ringPos = (ringPos + 1) & 0xFFF;
+                        offset = (offset + 1) & 0xFFF;
+                    }
+                }
+            }
+        }
+
+        File.WriteAllBytes(outputPath, output.ToArray());
+        Console.WriteLine($"Decompressed {output.Length} bytes to {outputPath}");
+    }
+}

src/YodaStoriesNG.Engine/Bot/MissionBot.cs

@@ -32,6 +32,9 @@ public class MissionBot
     // Random for exploration
     private readonly Random _random = new();
 
+    // Track NPCs we can't reach (to avoid retrying forever)
+    private readonly HashSet<(int, int)> _unreachableNpcs = new();
+
     // Events
     public event Action<BotActionType, int, int, Direction>? OnActionRequested;
 
@@ -95,6 +98,7 @@ public class MissionBot
         _stuckTimer = 0;
         _explorationAttempts = 0;
         _lastPosition = (_state.PlayerX, _state.PlayerY, _state.CurrentZoneId);
+        _unreachableNpcs.Clear();
 
         Console.WriteLine("[BOT] Started");
         LogMissionState();
@@ -344,13 +348,21 @@ public class MissionBot
 
         // Check if there's anything useful in current zone first
         var friendlyNpc = _solver.FindNearestFriendlyNpc();
-        if (friendlyNpc != null)
+        if (friendlyNpc != null && !_unreachableNpcs.Contains((friendlyNpc.X, friendlyNpc.Y)))
         {
             Console.WriteLine($"[BOT] Found friendly NPC at ({friendlyNpc.X},{friendlyNpc.Y})");
-            _actions.TalkToNpc(friendlyNpc);
+            if (_actions.TalkToNpc(friendlyNpc))
+            {
                 _currentState = BotState.ExecutingObjective;
                 return;
             }
+            else
+            {
+                // Couldn't find path to this NPC, mark as unreachable
+                Console.WriteLine($"[BOT] Marking NPC at ({friendlyNpc.X},{friendlyNpc.Y}) as unreachable");
+                _unreachableNpcs.Add((friendlyNpc.X, friendlyNpc.Y));
+            }
+        }
 
         // Look for unexplored doors
         var door = _solver.FindUnexploredDoor();
@@ -490,6 +502,14 @@ public class MissionBot
     {
         var currentPos = (_state.PlayerX, _state.PlayerY, _state.CurrentZoneId);
 
+        // Clear unreachable NPCs when zone changes
+        if (currentPos.CurrentZoneId != _lastPosition.ZoneId)
+        {
+            Console.WriteLine($"[BOT] Zone changed to {currentPos.CurrentZoneId}, clearing unreachable NPCs");
+            _unreachableNpcs.Clear();
+            _explorationAttempts = 0;
+        }
+
         if (currentPos == _lastPosition)
         {
             _stuckTimer += deltaTime;

src/YodaStoriesNG.Engine/Game/ActionExecutor.cs

@@ -15,6 +15,12 @@ public class ActionExecutor
     // Action execution context
     private int _lastRandomValue;
     private Zone? _currentZone;
+    private ActionTrigger _currentTrigger;
+
+    /// <summary>
+    /// When true, dialogue instructions are suppressed.
+    /// </summary>
+    public bool SuppressDialogue { get; set; }
 
     // Current interaction context
     public int? PlacedItemId { get; set; }
@@ -40,6 +46,7 @@ public class ActionExecutor
     public void ExecuteZoneActions(ActionTrigger trigger)
     {
         _currentZone = _state.CurrentZone;
+        _currentTrigger = trigger;
         if (_currentZone == null)
             return;
 
@@ -52,6 +59,16 @@ public class ActionExecutor
         }
     }
 
+    /// <summary>
+    /// Returns true if the current trigger is player-initiated (NpcTalk, UseItem).
+    /// Dialogue should only show for these triggers, not for ZoneEnter, Walk, Bump, etc.
+    /// </summary>
+    private bool IsPlayerInitiatedTrigger()
+    {
+        return _currentTrigger == ActionTrigger.NpcTalk ||
+               _currentTrigger == ActionTrigger.UseItem;
+    }
+
     private bool EvaluateConditions(List<Condition> conditions, ActionTrigger trigger)
     {
         foreach (var condition in conditions)
@@ -339,7 +356,8 @@ public class ActionExecutor
                 break;
 
             case InstructionOpcode.SpeakHero:
-                if (!string.IsNullOrEmpty(instruction.Text))
+                // Only show dialogue if not suppressed AND trigger is player-initiated
+                if (!string.IsNullOrEmpty(instruction.Text) && !SuppressDialogue && IsPlayerInitiatedTrigger())
                 {
                     OnDialogue?.Invoke("Luke", instruction.Text);
                 }
@@ -347,7 +365,8 @@ public class ActionExecutor
 
             case InstructionOpcode.SpeakNpc:
             case InstructionOpcode.SpeakNpc2:
-                if (!string.IsNullOrEmpty(instruction.Text))
+                // Only show dialogue if not suppressed AND trigger is player-initiated
+                if (!string.IsNullOrEmpty(instruction.Text) && !SuppressDialogue && IsPlayerInitiatedTrigger())
                 {
                     // Get NPC name from argument if provided
                     string npcName = "NPC";

src/YodaStoriesNG.Engine/Game/GameState.cs

@@ -36,6 +36,7 @@ public class GameState
     public bool IsGameOver { get; set; }
     public bool IsGameWon { get; set; }
     public bool IsPaused { get; set; }
+    public bool HasLocator { get; set; }  // Has picked up R2D2/locator droid
 
     // Animation state
     public int AnimationFrame { get; set; }
@@ -89,6 +90,7 @@ public class GameState
         IsGameOver = false;
         IsGameWon = false;
         IsPaused = false;
+        HasLocator = false;
         AnimationFrame = 0;
         AnimationTimer = 0;
         CameraX = 0;

src/YodaStoriesNG.Engine/Game/WorldGenerator.cs

@@ -220,18 +220,19 @@ public class WorldGenerator
 
     /// <summary>
     /// Parses and dumps IZAX entity data.
-    /// IZAX format: 2 bytes count, then for each entity: charId(2), x(2), y(2), itemTile(2), itemQuantity(2), data(6)
+    /// IZAX format: 4 bytes header, 2 bytes count, then for each entity: charId(2), x(2), y(2), itemTile(2), itemQuantity(2), data(6)
     /// </summary>
     private void DumpIzaxEntities(byte[] izaxData)
     {
-        if (izaxData.Length < 2) return;
+        if (izaxData.Length < 6) return;
 
         using var ms = new MemoryStream(izaxData);
         using var reader = new BinaryReader(ms);
 
         try
         {
-            // IZAX starts with entity count (2 bytes)
+            // Skip 4-byte header, then read entity count (2 bytes)
+            reader.ReadUInt32();
             var entityCount = reader.ReadUInt16();
             Console.WriteLine($"    Entity count: {entityCount}");
 
@@ -542,14 +543,11 @@ public class WorldGenerator
         CurrentWorld.StartingZoneId = dagobahZones[0];  // Should be 93
         CurrentWorld.XWingZoneId = CurrentWorld.StartingZoneId;
 
-        // Randomly pick one of 4 positions for Yoda to appear
-        // (Yoda can appear in any of the 4 Dagobah outdoor zones)
-        var yodaZoneIndex = _random.Next(Math.Min(4, dagobahZones.Count));
-        CurrentWorld.YodaZoneId = dagobahZones[yodaZoneIndex];
+        // Yoda always appears in the starting zone for easy access
+        CurrentWorld.YodaZoneId = CurrentWorld.StartingZoneId;
 
-        // Random position within the zone for Yoda (4 possible positions)
-        var yodaPositions = new[] { (5, 5), (12, 5), (5, 12), (12, 12) };
-        CurrentWorld.YodaPosition = yodaPositions[_random.Next(yodaPositions.Length)];
+        // Yoda spawns near the player (player starts around 13,4, Yoda at 11,4)
+        CurrentWorld.YodaPosition = (11, 4);
 
         Console.WriteLine($"Yoda will appear in zone {CurrentWorld.YodaZoneId} at position {CurrentWorld.YodaPosition}");
 

src/YodaStoriesNG.Engine/Parsing/DtaParser.cs

@@ -458,20 +458,23 @@ public class DtaParser
 
     /// <summary>
     /// Parses IZAX entity data from raw bytes.
-    /// IZAX format: 2 bytes count, then for each entity: charId(2), x(2), y(2), itemTile(2), itemQty(2), data(6)
+    /// IZAX format: 4 bytes header, 2 bytes count, then for each entity: charId(2), x(2), y(2), itemTile(2), itemQty(2), data(6)
     /// </summary>
     private ZoneAuxData ParseIZAXData(byte[] data)
     {
         var auxData = new ZoneAuxData { RawData = data };
 
         // Parse entity data from raw bytes
-        if (data.Length >= 2)
+        // IZAX has a 4-byte header before the entity count
+        if (data.Length >= 6)
         {
             using var ms = new MemoryStream(data);
             using var entityReader = new BinaryReader(ms);
 
             try
             {
+                // Skip 4-byte header
+                entityReader.ReadUInt32();
                 var entityCount = entityReader.ReadUInt16();
 
                 // Each entity is 16 bytes: charId(2) + x(2) + y(2) + itemTile(2) + itemQty(2) + data(6)

src/YodaStoriesNG.Engine/UI/MessageSystem.cs

@@ -163,4 +163,13 @@ public class MessageSystem
         _messageQueue.Clear();
         _currentDialogue = null;
     }
+
+    /// <summary>
+    /// Clears only dialogue (the left-side box), keeping other messages.
+    /// </summary>
+    public void ClearDialogue()
+    {
+        _messageQueue.Clear();
+        _currentDialogue = null;
+    }
 }