Add last visited station condition.

src/lang/english.txt

@@ -2386,6 +2386,7 @@ STR_TRACE_RESTRICT_VARIABLE_TRAIN_LENGTH                        :train length
 STR_TRACE_RESTRICT_VARIABLE_MAX_SPEED                           :max speed
 STR_TRACE_RESTRICT_VARIABLE_CURRENT_ORDER                       :current order
 STR_TRACE_RESTRICT_VARIABLE_NEXT_ORDER                          :next order
+STR_TRACE_RESTRICT_VARIABLE_LAST_VISITED_STATION                :last visited station
 STR_TRACE_RESTRICT_VARIABLE_UNDEFINED                           :undefined
 STR_TRACE_RESTRICT_CONDITIONAL_COMPARE_INTEGER                  :{STRING} {STRING} {STRING} {COMMA} then
 STR_TRACE_RESTRICT_CONDITIONAL_COMPARE_SPEED                    :{STRING} {STRING} {STRING} {VELOCITY} then

src/tracerestrict.cpp

@@ -132,6 +132,21 @@ static bool TestCondition(uint16 value, TraceRestrictCondOp condop, uint16 condv
 	}
 }
 
+static bool TestBinaryConditionCommon(TraceRestrictItem item, bool input)
+{
+	switch (GetTraceRestrictCondOp(item)) {
+		case TRCO_IS:
+			return input;
+
+		case TRCO_ISNOT:
+			return !input;
+
+		default:
+			NOT_REACHED();
+			return false;
+	}
+}
+
 /// Test order condition
 /// order may be NULL
 static bool TestOrderCondition(const Order *order, TraceRestrictItem item)
@@ -157,18 +172,15 @@ static bool TestOrderCondition(const Order *order, TraceRestrictItem item)
 				NOT_REACHED();
 		}
 	}
+	return TestBinaryConditionCommon(item, result);
+}
 
-	switch (GetTraceRestrictCondOp(item)) {
-		case TRCO_IS:
-			return result;
-
-		case TRCO_ISNOT:
-			return !result;
+/// Test station condition
+static bool TestStationCondition(StationID station, TraceRestrictItem item)
+{
+	bool result = (GetTraceRestrictAuxField(item) == TROCAF_STATION) && (station == GetTraceRestrictValue(item));
+	return TestBinaryConditionCommon(item, result);
 
-		default:
-			NOT_REACHED();
-			return false;
-	}
 }
 
 /// Execute program on train and store results in out
@@ -232,6 +244,10 @@ void TraceRestrictProgram::Execute(const Train* v, TraceRestrictProgramResult& o
 						break;
 					}
 
+					case TRIT_COND_LAST_STATION:
+						result = TestStationCondition(v->last_station_visited, item);
+						break;
+
 					default:
 						NOT_REACHED();
 				}
@@ -752,7 +768,8 @@ void TraceRestrictRemoveDestinationID(TraceRestrictOrderCondAuxField type, uint1
 		for (size_t i = 0; i < prog->items.size(); i++) {
 			TraceRestrictItem &item = prog->items[i]; // note this is a reference,
 			if (GetTraceRestrictType(item) == TRIT_COND_CURRENT_ORDER ||
-					GetTraceRestrictType(item) == TRIT_COND_NEXT_ORDER) {
+					GetTraceRestrictType(item) == TRIT_COND_NEXT_ORDER ||
+					GetTraceRestrictType(item) == TRIT_COND_LAST_STATION) {
 				if (GetTraceRestrictAuxField(item) == type && GetTraceRestrictValue(item) == index) {
 					SetTraceRestrictValueDefault(item, TRVT_ORDER); // this updates the instruction in-place
 				}

src/tracerestrict.h

@@ -84,6 +84,7 @@ enum TraceRestrictItemType {
 	TRIT_COND_MAX_SPEED           = 11,   ///< Test train max speed
 	TRIT_COND_CURRENT_ORDER       = 12,   ///< Test train current order (station, waypoint or depot)
 	TRIT_COND_NEXT_ORDER          = 13,   ///< Test train next order (station, waypoint or depot)
+	TRIT_COND_LAST_STATION        = 14,   ///< Test train last visited station
 	/* space up to 31 */
 };
 
@@ -191,8 +192,6 @@ static inline void SetTraceRestrictAuxField(TraceRestrictItem &item, uint8 data)
 	SB(item, TRIFA_AUX_FIELD_OFFSET, TRIFA_AUX_FIELD_COUNT, data);
 }
 
-void SetTraceRestrictTypeAndNormalise(TraceRestrictItem &item, TraceRestrictItemType type);
-
 static inline void SetTraceRestrictValue(TraceRestrictItem &item, uint16 value)
 {
 	SB(item, TRIFA_VALUE_OFFSET, TRIFA_VALUE_COUNT, value);
@@ -223,6 +222,9 @@ enum TraceRestrictValueType {
 	TRVT_ORDER                    = 5, ///< takes an order target ID, as per the auxiliary field as type: TraceRestrictOrderCondAuxField
 };
 
+void SetTraceRestrictValueDefault(TraceRestrictItem &item, TraceRestrictValueType value_type);
+void SetTraceRestrictTypeAndNormalise(TraceRestrictItem &item, TraceRestrictItemType type);
+
 struct TraceRestrictTypePropertySet {
 	TraceRestrictConditionOpType cond_type;
 	TraceRestrictValueType value_type;
@@ -253,6 +255,7 @@ static inline TraceRestrictTypePropertySet GetTraceRestrictTypeProperties(TraceR
 
 			case TRIT_COND_CURRENT_ORDER:
 			case TRIT_COND_NEXT_ORDER:
+			case TRIT_COND_LAST_STATION:
 				out.value_type = TRVT_ORDER;
 				out.cond_type = TRCOT_BINARY;
 				break;

src/tracerestrict_gui.cpp

@@ -160,6 +160,7 @@ static const TraceRestrictDropDownListSet *GetTypeDropDownListSet(TraceRestrictI
 		STR_TRACE_RESTRICT_VARIABLE_MAX_SPEED,
 		STR_TRACE_RESTRICT_VARIABLE_CURRENT_ORDER,
 		STR_TRACE_RESTRICT_VARIABLE_NEXT_ORDER,
+		STR_TRACE_RESTRICT_VARIABLE_LAST_VISITED_STATION,
 		STR_TRACE_RESTRICT_VARIABLE_UNDEFINED,
 		INVALID_STRING_ID,
 	};
@@ -168,6 +169,7 @@ static const TraceRestrictDropDownListSet *GetTypeDropDownListSet(TraceRestrictI
 		TRIT_COND_MAX_SPEED,
 		TRIT_COND_CURRENT_ORDER,
 		TRIT_COND_NEXT_ORDER,
+		TRIT_COND_LAST_STATION,
 		TRIT_COND_UNDEFINED,
 	};
 	static const TraceRestrictDropDownListSet set_cond = {
@@ -599,6 +601,10 @@ public:
 
 			case TR_WIDGET_TYPE: {
 				SetTraceRestrictTypeAndNormalise(item, static_cast<TraceRestrictItemType>(value));
+				if (GetTraceRestrictType(item) == TRIT_COND_LAST_STATION && GetTraceRestrictAuxField(item) != TROCAF_STATION) {
+					// if changing type from another order type to last visited station, reset value if not currently a station
+					SetTraceRestrictValueDefault(item, TRVT_ORDER);
+				}
 				TraceRestrictDoCommandP(this->tile, this->track, TRDCT_MODIFY_ITEM, this->selected_instruction - 1, item, STR_TRACE_RESTRICT_ERROR_CAN_T_MODIFY_ITEM);
 				break;
 			}
@@ -701,10 +707,14 @@ public:
 		TraceRestrictItem item = GetSelected();
 		if (GetTraceRestrictTypeProperties(item).value_type != TRVT_ORDER) return;
 
+		bool stations_only = (GetTraceRestrictType(item) == TRIT_COND_LAST_STATION);
+
 		if (IsDepotTypeTile(tile, TRANSPORT_RAIL)) {
+			if (stations_only) return;
 			SetTraceRestrictValue(item, GetDepotIndex(tile));
 			SetTraceRestrictAuxField(item, TROCAF_DEPOT);
 		} else if (IsRailWaypointTile(tile)) {
+			if (stations_only) return;
 			SetTraceRestrictValue(item, GetStationIndex(tile));
 			SetTraceRestrictAuxField(item, TROCAF_WAYPOINT);
 		} else if (IsTileType(tile, MP_STATION)) {