From e9c33fb288939a9725cdfd17a11870079c011f08 Mon Sep 17 00:00:00 2001
From: rubidium <rubidium@openttd.org>
Date: Sat, 2 Aug 2008 22:53:21 +0000
Subject: [PATCH] (svn r13950) -Add [YAPP]: Trains can now also be in a 'stuck'
 state when waiting on a path reservation. (michi_cc)

---
 src/lang/english.txt |  1 +
 src/train_cmd.cpp    | 34 +++++++++++++++++++++++++++++-----
 src/vehicle.cpp      |  3 ++-
 src/vehicle_base.h   |  5 ++++-
 src/vehicle_gui.cpp  |  2 ++
 5 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/src/lang/english.txt b/src/lang/english.txt
index fbdf4ae4e4..915a99da0b 100644
--- a/src/lang/english.txt
+++ b/src/lang/english.txt
@@ -2905,6 +2905,7 @@ STR_TRAIN_STOPPING_VEL                                          :{RED}Stopping,
 STR_INCOMPATIBLE_RAIL_TYPES                                     :Incompatible rail types
 STR_TRAIN_NO_POWER                                              :{RED}No power
 STR_TRAIN_START_NO_CATENARY                                     :This track lacks catenary, so the train can't start
+STR_TRAIN_STUCK                                                 :{ORANGE}Waiting for free path
 
 STR_NEW_VEHICLE_NOW_AVAILABLE                                   :{BLACK}{BIGFONT}New {STRING} now available!
 STR_NEW_VEHICLE_TYPE                                            :{BLACK}{BIGFONT}{ENGINE}
diff --git a/src/train_cmd.cpp b/src/train_cmd.cpp
index 229f70d300..6b6f548ed4 100644
--- a/src/train_cmd.cpp
+++ b/src/train_cmd.cpp
@@ -1614,10 +1614,27 @@ static inline void SetLastSpeed(Vehicle *v, int spd)
 	}
 }
 
-static void SwapTrainFlags(byte *swap_flag1, byte *swap_flag2)
+/** Mark a train as stuck and stop it if it isn't stopped right now. */
+static void MarkTrainAsStuck(Vehicle *v)
 {
-	byte flag1 = *swap_flag1;
-	byte flag2 = *swap_flag2;
+	if (!HasBit(v->u.rail.flags, VRF_TRAIN_STUCK)) {
+		/* It is the first time the problem occured, set the "train stuck" flag. */
+		SetBit(v->u.rail.flags, VRF_TRAIN_STUCK);
+		v->load_unload_time_rem	= 0;
+
+		/* Stop train */
+		v->cur_speed = 0;
+		v->subspeed = 0;
+		SetLastSpeed(v, 0);
+
+		InvalidateWindowWidget(WC_VEHICLE_VIEW, v->index, VVW_WIDGET_START_STOP_VEH);
+	}
+}
+
+static void SwapTrainFlags(uint16 *swap_flag1, uint16 *swap_flag2)
+{
+	uint16 flag1 = *swap_flag1;
+	uint16 flag2 = *swap_flag2;
 
 	/* Clear the flags */
 	ClrBit(*swap_flag1, VRF_GOINGUP);
@@ -2670,7 +2687,7 @@ static int UpdateTrainSpeed(Vehicle *v)
 {
 	uint accel;
 
-	if (v->vehstatus & VS_STOPPED || HasBit(v->u.rail.flags, VRF_REVERSING)) {
+	if (v->vehstatus & VS_STOPPED || HasBit(v->u.rail.flags, VRF_REVERSING) || HasBit(v->u.rail.flags, VRF_TRAIN_STUCK)) {
 		if (_settings_game.vehicle.realistic_acceleration) {
 			accel = GetTrainAcceleration(v, AM_BRAKE) * 2;
 		} else {
@@ -3059,6 +3076,9 @@ static void TrainController(Vehicle *v, Vehicle *nomove, bool update_image)
 						/* In front of a red signal */
 						Trackdir i = FindFirstTrackdir(trackdirbits);
 
+						/* Don't handle stuck trains here. */
+						if (HasBit(v->u.rail.flags, VRF_TRAIN_STUCK)) return;
+
 						if (!HasSignalOnTrackdir(gp.new_tile, ReverseTrackdir(i))) {
 							v->cur_speed = 0;
 							v->subspeed = 0;
@@ -3499,7 +3519,11 @@ static void TrainLocoHandler(Vehicle *v, bool mode)
 		return;
 	}
 
-	if (v->u.rail.force_proceed != 0) v->u.rail.force_proceed--;
+	if (v->u.rail.force_proceed != 0) {
+		v->u.rail.force_proceed--;
+		ClrBit(v->u.rail.flags, VRF_TRAIN_STUCK);
+		InvalidateWindowWidget(WC_VEHICLE_VIEW, v->index, VVW_WIDGET_START_STOP_VEH);
+	}
 
 	/* train is broken down? */
 	if (v->breakdown_ctr != 0) {
diff --git a/src/vehicle.cpp b/src/vehicle.cpp
index 18195eef2c..555f1ddf07 100644
--- a/src/vehicle.cpp
+++ b/src/vehicle.cpp
@@ -2072,7 +2072,8 @@ static const SaveLoad _train_desc[] = {
 	    SLE_VARX(cpp_offsetof(Vehicle, u) + cpp_offsetof(VehicleRail, railtype),               SLE_UINT8),
 	    SLE_VARX(cpp_offsetof(Vehicle, u) + cpp_offsetof(VehicleRail, track),                  SLE_UINT8),
 
-	SLE_CONDVARX(cpp_offsetof(Vehicle, u) + cpp_offsetof(VehicleRail, flags),                  SLE_UINT8,  2, SL_MAX_VERSION),
+	SLE_CONDVARX(cpp_offsetof(Vehicle, u) + cpp_offsetof(VehicleRail, flags), SLE_FILE_U8  | SLE_VAR_U16,  2, 99),
+	SLE_CONDVARX(cpp_offsetof(Vehicle, u) + cpp_offsetof(VehicleRail, flags),                 SLE_UINT16,100, SL_MAX_VERSION),
 	SLE_CONDNULL(2, 2, 59),
 
 	SLE_CONDNULL(2, 2, 19),
diff --git a/src/vehicle_base.h b/src/vehicle_base.h
index 0defc9566e..440f30d1d5 100644
--- a/src/vehicle_base.h
+++ b/src/vehicle_base.h
@@ -115,7 +115,7 @@ struct VehicleRail {
 	 * 0xffff == not in train */
 	EngineID first_engine;
 
-	byte flags;
+	uint16 flags;
 	TrackBitsByte track;
 	byte force_proceed;
 	RailTypeByte railtype;
@@ -143,6 +143,9 @@ enum VehicleRailFlags {
 
 	/* used for vehicle var 0xFE bit 8 (toggled each time the train is reversed, accurate for first vehicle only) */
 	VRF_TOGGLE_REVERSE = 7,
+
+	/* used to mark a train that can't get a path reservation */
+	VRF_TRAIN_STUCK    = 8,
 };
 
 struct VehicleAir {
diff --git a/src/vehicle_gui.cpp b/src/vehicle_gui.cpp
index faf0447645..fda939d35c 100644
--- a/src/vehicle_gui.cpp
+++ b/src/vehicle_gui.cpp
@@ -1895,6 +1895,8 @@ struct VehicleViewWindow : Window {
 			} else { // no train
 				str = STR_8861_STOPPED;
 			}
+		} else if (v->type == VEH_TRAIN && HasBit(v->u.rail.flags, VRF_TRAIN_STUCK)) {
+			str = STR_TRAIN_STUCK;
 		} else { // vehicle is in a "normal" state, show current order
 			switch (v->current_order.GetType()) {
 				case OT_GOTO_STATION: {