Core/MovementGenerator: Add more details to asserts

Implement GetDebugInfo in MovementGenerator, PathMovementBase, FlightPathMovementGenerator, WaypointMovementGenerator.
Add an additional assert in FlightPathMovementGenerator::DoEventIfAny(), the input node must not be null

src/server/game/Movement/MovementGenerator.cpp

@@ -26,6 +26,17 @@
 
 MovementGenerator::~MovementGenerator() { }
 
+std::string MovementGenerator::GetDebugInfo() const
+{
+    std::stringstream sstr;
+    sstr << std::boolalpha
+        << "Mode: " << std::to_string(Mode)
+        << " Priority: " << std::to_string(Priority)
+        << " Flags: " << Flags
+        << " BaseUniteState: " << BaseUnitState;
+    return sstr.str();
+}
+
 IdleMovementFactory::IdleMovementFactory() : MovementGeneratorCreator(IDLE_MOTION_TYPE) { }
 
 MovementGenerator* IdleMovementFactory::Create(Unit* /*object*/) const

src/server/game/Movement/MovementGenerator.h

@@ -74,6 +74,8 @@ class TC_GAME_API MovementGenerator
         bool HasFlag(uint16 const flag) const { return (Flags & flag) != 0; }
         void RemoveFlag(uint16 const flag) { Flags &= ~flag; }
 
+        virtual std::string GetDebugInfo() const;
+
         uint8 Mode;
         uint8 Priority;
         uint16 Flags;

src/server/game/Movement/MovementGenerators/FlightPathMovementGenerator.cpp

@@ -235,6 +235,8 @@ void FlightPathMovementGenerator::SetCurrentNodeAfterTeleport()
 
 void FlightPathMovementGenerator::DoEventIfAny(Player* owner, TaxiPathNodeEntry const* node, bool departure)
 {
+    ASSERT(node);
+
     if (uint32 eventid = departure ? node->DepartureEventID : node->ArrivalEventID)
     {
         TC_LOG_DEBUG("maps.script", "FlightPathMovementGenerator::DoEventIfAny: taxi %s event %u of node %u of path %u for player %s", departure ? "departure" : "arrival", eventid, node->NodeIndex, node->PathID, owner->GetName().c_str());
@@ -273,3 +275,27 @@ void FlightPathMovementGenerator::PreloadEndGrid()
     else
         TC_LOG_DEBUG("movement.flightpath", "FlightPathMovementGenerator::PreloadEndGrid: unable to determine map to preload flightmaster grid");
 }
+
+uint32 FlightPathMovementGenerator::GetPathId(size_t index) const
+{
+    if (index >= _path.size())
+        return 0;
+
+    return _path[index]->PathID;
+}
+
+std::string FlightPathMovementGenerator::GetDebugInfo() const
+{
+    std::stringstream sstr;
+    sstr << std::boolalpha
+        << PathMovementBase::GetDebugInfo() << "\n"
+        << MovementGeneratorMedium::GetDebugInfo() << "\n"
+        << "Start Path Id: " << GetPathId(0)
+        << " Path Size: " << _path.size()
+        << " HasArrived: " << HasArrived()
+        << " End Grid X: " << _endGridX
+        << " End Grid Y: " << _endGridY
+        << " End Map Id: " << _endMapId
+        << " Preloaded Target Node: " << _preloadTargetNode;
+    return sstr.str();
+}

src/server/game/Movement/MovementGenerators/FlightPathMovementGenerator.h

@@ -46,6 +46,7 @@ class FlightPathMovementGenerator : public MovementGeneratorMedium<Player, Fligh
         TaxiPathNodeList const& GetPath() { return _path; }
         uint32 GetPathAtMapEnd() const;
         bool HasArrived() const { return _currentNode >= _path.size(); }
+        uint32 GetPathId(size_t index) const;
 
         void LoadPath(Player* owner); // called from MotionMaster
         void SetCurrentNodeAfterTeleport();
@@ -54,6 +55,8 @@ class FlightPathMovementGenerator : public MovementGeneratorMedium<Player, Fligh
         void InitEndGridInfo();
         void PreloadEndGrid();
 
+        std::string GetDebugInfo() const override;
+
     private:
         float _endGridX; //! X coord of last node location
         float _endGridY; //! Y coord of last node location

src/server/game/Movement/MovementGenerators/PathMovementBase.h

@@ -19,6 +19,7 @@
 #define PathMovementBase_h__
 
 #include "Define.h"
+#include <sstream>
 
 template<class Entity, class BasePath>
 class PathMovementBase
@@ -29,6 +30,14 @@ class PathMovementBase
 
         uint32 GetCurrentNode() const { return _currentNode; }
 
+        virtual std::string GetDebugInfo() const
+        {
+            std::stringstream sstr;
+            sstr << std::boolalpha
+                << "Current Node: " << GetCurrentNode();
+            return sstr.str();
+        };
+
     protected:
         BasePath _path;
         uint32 _currentNode;

src/server/game/Movement/MovementGenerators/WaypointMovementGenerator.cpp

@@ -390,3 +390,11 @@ bool WaypointMovementGenerator<Creature>::ComputeNextNode()
     _currentNode = (_currentNode + 1) % _path->nodes.size();
     return true;
 }
+
+std::string WaypointMovementGenerator<Creature>::GetDebugInfo() const
+{
+    std::stringstream sstr;
+    sstr << PathMovementBase::GetDebugInfo() << "\n"
+        << MovementGeneratorMedium::GetDebugInfo();
+    return sstr.str();
+}

src/server/game/Movement/MovementGenerators/WaypointMovementGenerator.h

@@ -51,6 +51,8 @@ class WaypointMovementGenerator<Creature> : public MovementGeneratorMedium<Creat
         void DoDeactivate(Creature*);
         void DoFinalize(Creature*, bool, bool);
 
+        std::string GetDebugInfo() const override;
+
     private:
         void MovementInform(Creature*);
         void OnArrived(Creature*);