rewrite location events for multiplayer

16 files changed, 532 insertions, 193 deletions

diff --git a/src/SMAPI/Events/EventArgsGameLocationsChanged.cs b/src/SMAPI/Events/EventArgsGameLocationsChanged.cs
deleted file mode 100644
index 78ba38fa..00000000
--- a/src/SMAPI/Events/EventArgsGameLocationsChanged.cs
+++ /dev/null
@@ -1,27 +0,0 @@
-using System;
-using System.Collections.Generic;
-using StardewValley;
-
-namespace StardewModdingAPI.Events
-{
-    /// <summary>Event arguments for a <see cref="LocationEvents.LocationsChanged"/> event.</summary>
-    public class EventArgsGameLocationsChanged : EventArgs
-    {
-        /*********
-        ** Accessors
-        *********/
-        /// <summary>The current list of game locations.</summary>
-        public IList<GameLocation> NewLocations { get; }
-
-
-        /*********
-        ** Public methods
-        *********/
-        /// <summary>Construct an instance.</summary>
-        /// <param name="newLocations">The current list of game locations.</param>
-        public EventArgsGameLocationsChanged(IList<GameLocation> newLocations)
-        {
-            this.NewLocations = newLocations;
-        }
-    }
-}
diff --git a/src/SMAPI/Events/EventArgsIntChanged.cs b/src/SMAPI/Events/EventArgsIntChanged.cs
index 0c742d12..a018695c 100644
--- a/src/SMAPI/Events/EventArgsIntChanged.cs
+++ b/src/SMAPI/Events/EventArgsIntChanged.cs
@@ -1,4 +1,4 @@
-using System;
+using System;
 
 namespace StardewModdingAPI.Events
 {
@@ -14,6 +14,7 @@ namespace StardewModdingAPI.Events
         /// <summary>The current value.</summary>
         public int NewInt { get; }
 
+
         /*********
         ** Public methods
         *********/
diff --git a/src/SMAPI/Events/EventArgsLocationBuildingsChanged.cs b/src/SMAPI/Events/EventArgsLocationBuildingsChanged.cs
new file mode 100644
index 00000000..e8184ebe
--- /dev/null
+++ b/src/SMAPI/Events/EventArgsLocationBuildingsChanged.cs
@@ -0,0 +1,39 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using StardewValley;
+using StardewValley.Buildings;
+
+namespace StardewModdingAPI.Events
+{
+    /// <summary>Event arguments for a <see cref="LocationEvents.BuildingsChanged"/> event.</summary>
+    public class EventArgsLocationBuildingsChanged : EventArgs
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The location which changed.</summary>
+        public GameLocation Location { get; }
+
+        /// <summary>The buildings added to the location.</summary>
+        public IEnumerable<Building> Added { get; }
+
+        /// <summary>The buildings removed from the location.</summary>
+        public IEnumerable<Building> Removed { get; }
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="location">The location which changed.</param>
+        /// <param name="added">The buildings added to the location.</param>
+        /// <param name="removed">The buildings removed from the location.</param>
+        public EventArgsLocationBuildingsChanged(GameLocation location, IEnumerable<Building> added, IEnumerable<Building> removed)
+        {
+            this.Location = location;
+            this.Added = added.ToArray();
+            this.Removed = removed.ToArray();
+        }
+    }
+}
diff --git a/src/SMAPI/Events/EventArgsLocationObjectsChanged.cs b/src/SMAPI/Events/EventArgsLocationObjectsChanged.cs
index a6138ddb..410ef6e6 100644
--- a/src/SMAPI/Events/EventArgsLocationObjectsChanged.cs
+++ b/src/SMAPI/Events/EventArgsLocationObjectsChanged.cs
@@ -8,7 +8,7 @@ using SObject = StardewValley.Object;
 
 namespace StardewModdingAPI.Events
 {
-    /// <summary>Event arguments for a <see cref="LocationEvents.LocationObjectsChanged"/> or <see cref="LocationEvents.ObjectsChanged"/> event.</summary>
+    /// <summary>Event arguments for a <see cref="LocationEvents.ObjectsChanged"/> event.</summary>
     public class EventArgsLocationObjectsChanged : EventArgs
     {
         /*********
@@ -17,31 +17,25 @@ namespace StardewModdingAPI.Events
         /// <summary>The location which changed.</summary>
         public GameLocation Location { get; }
 
-        /// <summary>The objects added to the list.</summary>
+        /// <summary>The objects added to the location.</summary>
         public IEnumerable<KeyValuePair<Vector2, SObject>> Added { get; }
 
-        /// <summary>The objects removed from the list.</summary>
+        /// <summary>The objects removed from the location.</summary>
         public IEnumerable<KeyValuePair<Vector2, SObject>> Removed { get; }
 
-        /// <summary>The current list of objects in the current location.</summary>
-        [Obsolete("Use " + nameof(EventArgsLocationObjectsChanged.Added))]
-        public IDictionary<Vector2, NetRef<SObject>> NewObjects { get; }
-
 
         /*********
         ** Public methods
         *********/
         /// <summary>Construct an instance.</summary>
         /// <param name="location">The location which changed.</param>
-        /// <param name="added">The objects added to the list.</param>
-        /// <param name="removed">The objects removed from the list.</param>
-        /// <param name="newObjects">The current list of objects in the current location.</param>
-        public EventArgsLocationObjectsChanged(GameLocation location, IEnumerable<KeyValuePair<Vector2, SObject>> added, IEnumerable<KeyValuePair<Vector2, SObject>> removed, IDictionary<Vector2, NetRef<SObject>> newObjects)
+        /// <param name="added">The objects added to the location.</param>
+        /// <param name="removed">The objects removed from the location.</param>
+        public EventArgsLocationObjectsChanged(GameLocation location, IEnumerable<KeyValuePair<Vector2, SObject>> added, IEnumerable<KeyValuePair<Vector2, SObject>> removed)
         {
             this.Location = location;
             this.Added = added.ToArray();
             this.Removed = removed.ToArray();
-            this.NewObjects = newObjects;
         }
     }
 }
diff --git a/src/SMAPI/Events/EventArgsLocationsChanged.cs b/src/SMAPI/Events/EventArgsLocationsChanged.cs
new file mode 100644
index 00000000..20984f45
--- /dev/null
+++ b/src/SMAPI/Events/EventArgsLocationsChanged.cs
@@ -0,0 +1,33 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using StardewValley;
+
+namespace StardewModdingAPI.Events
+{
+    /// <summary>Event arguments for a <see cref="LocationEvents.LocationsChanged"/> event.</summary>
+    public class EventArgsLocationsChanged : EventArgs
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The added locations.</summary>
+        public IEnumerable<GameLocation> Added { get; }
+
+        /// <summary>The removed locations.</summary>
+        public IEnumerable<GameLocation> Removed { get; }
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="added">The added locations.</param>
+        /// <param name="removed">The removed locations.</param>
+        public EventArgsLocationsChanged(IEnumerable<GameLocation> added, IEnumerable<GameLocation> removed)
+        {
+            this.Added = added.ToArray();
+            this.Removed = removed.ToArray();
+        }
+    }
+}
diff --git a/src/SMAPI/Events/EventArgsCurrentLocationChanged.cs b/src/SMAPI/Events/EventArgsPlayerWarped.cs
index 25d3ebf3..93026aea 100644
--- a/src/SMAPI/Events/EventArgsCurrentLocationChanged.cs
+++ b/src/SMAPI/Events/EventArgsPlayerWarped.cs
@@ -1,19 +1,20 @@
-using System;
+using System;
 using StardewValley;
 
 namespace StardewModdingAPI.Events
 {
-    /// <summary>Event arguments for a <see cref="LocationEvents.CurrentLocationChanged"/> event.</summary>
-    public class EventArgsCurrentLocationChanged : EventArgs
+    /// <summary>Event arguments for a <see cref="PlayerEvents.Warped"/> event.</summary>
+    public class EventArgsPlayerWarped : EventArgs
     {
         /*********
         ** Accessors
         *********/
+        /// <summary>The player's previous location.</summary>
+        public GameLocation PriorLocation { get; }
+
         /// <summary>The player's current location.</summary>
         public GameLocation NewLocation { get; }
 
-        /// <summary>The player's previous location.</summary>
-        public GameLocation PriorLocation { get; }
 
 
         /*********
@@ -22,7 +23,7 @@ namespace StardewModdingAPI.Events
         /// <summary>Construct an instance.</summary>
         /// <param name="priorLocation">The player's previous location.</param>
         /// <param name="newLocation">The player's current location.</param>
-        public EventArgsCurrentLocationChanged(GameLocation priorLocation, GameLocation newLocation)
+        public EventArgsPlayerWarped(GameLocation priorLocation, GameLocation newLocation)
         {
             this.NewLocation = newLocation;
             this.PriorLocation = priorLocation;
diff --git a/src/SMAPI/Events/LocationEvents.cs b/src/SMAPI/Events/LocationEvents.cs
index 3ed09136..ff75c619 100644
--- a/src/SMAPI/Events/LocationEvents.cs
+++ b/src/SMAPI/Events/LocationEvents.cs
@@ -16,29 +16,21 @@ namespace StardewModdingAPI.Events
         /*********
         ** Events
         *********/
-        /// <summary>Raised after the player warps to a new location.</summary>
-        public static event EventHandler<EventArgsCurrentLocationChanged> CurrentLocationChanged
-        {
-            add => LocationEvents.EventManager.Location_CurrentLocationChanged.Add(value);
-            remove => LocationEvents.EventManager.Location_CurrentLocationChanged.Remove(value);
-        }
-
         /// <summary>Raised after a game location is added or removed.</summary>
-        public static event EventHandler<EventArgsGameLocationsChanged> LocationsChanged
+        public static event EventHandler<EventArgsLocationsChanged> LocationsChanged
         {
             add => LocationEvents.EventManager.Location_LocationsChanged.Add(value);
             remove => LocationEvents.EventManager.Location_LocationsChanged.Remove(value);
         }
 
-        /// <summary>Raised after the list of objects in the current location changes (e.g. an object is added or removed).</summary>
-        [Obsolete("Use " + nameof(LocationEvents) + "." + nameof(LocationEvents.ObjectsChanged) + " instead")]
-        public static event EventHandler<EventArgsLocationObjectsChanged> LocationObjectsChanged
+        /// <summary>Raised after buildings are added or removed in a location.</summary>
+        public static event EventHandler<EventArgsLocationBuildingsChanged> BuildingsChanged
         {
-            add => LocationEvents.EventManager.Location_LocationObjectsChanged.Add(value);
-            remove => LocationEvents.EventManager.Location_LocationObjectsChanged.Remove(value);
+            add => LocationEvents.EventManager.Location_BuildingsChanged.Add(value);
+            remove => LocationEvents.EventManager.Location_BuildingsChanged.Remove(value);
         }
 
-        /// <summary>Raised after the list of objects in a location changes (e.g. an object is added or removed).</summary>
+        /// <summary>Raised after objects are added or removed in a location.</summary>
         public static event EventHandler<EventArgsLocationObjectsChanged> ObjectsChanged
         {
             add => LocationEvents.EventManager.Location_ObjectsChanged.Add(value);
diff --git a/src/SMAPI/Events/PlayerEvents.cs b/src/SMAPI/Events/PlayerEvents.cs
index 84a7ff63..6e7050e3 100644
--- a/src/SMAPI/Events/PlayerEvents.cs
+++ b/src/SMAPI/Events/PlayerEvents.cs
@@ -23,13 +23,21 @@ namespace StardewModdingAPI.Events
             remove => PlayerEvents.EventManager.Player_InventoryChanged.Remove(value);
         }
 
-        /// <summary> Raised after the player levels up a skill. This happens as soon as they level up, not when the game notifies the player after their character goes to bed.</summary>
+        /// <summary>Raised after the player levels up a skill. This happens as soon as they level up, not when the game notifies the player after their character goes to bed.</summary>
         public static event EventHandler<EventArgsLevelUp> LeveledUp
         {
             add => PlayerEvents.EventManager.Player_LeveledUp.Add(value);
             remove => PlayerEvents.EventManager.Player_LeveledUp.Remove(value);
         }
 
+        /// <summary>Raised after the player warps to a new location.</summary>
+        public static event EventHandler<EventArgsPlayerWarped> Warped
+        {
+            add => PlayerEvents.EventManager.Player_Warped.Add(value);
+            remove => PlayerEvents.EventManager.Player_Warped.Remove(value);
+        }
+
+
 
         /*********
         ** Public methods
diff --git a/src/SMAPI/Framework/Events/EventManager.cs b/src/SMAPI/Framework/Events/EventManager.cs
index 9030ba97..84036127 100644
--- a/src/SMAPI/Framework/Events/EventManager.cs
+++ b/src/SMAPI/Framework/Events/EventManager.cs
@@ -108,17 +108,13 @@ namespace StardewModdingAPI.Framework.Events
         /****
         ** LocationEvents
         ****/
-        /// <summary>Raised after the player warps to a new location.</summary>
-        public readonly ManagedEvent<EventArgsCurrentLocationChanged> Location_CurrentLocationChanged;
-
         /// <summary>Raised after a game location is added or removed.</summary>
-        public readonly ManagedEvent<EventArgsGameLocationsChanged> Location_LocationsChanged;
+        public readonly ManagedEvent<EventArgsLocationsChanged> Location_LocationsChanged;
 
-        /// <summary>Raised after the list of objects in the current location changes (e.g. an object is added or removed).</summary>
-        [Obsolete]
-        public readonly ManagedEvent<EventArgsLocationObjectsChanged> Location_LocationObjectsChanged;
+        /// <summary>Raised after buildings are added or removed in a location.</summary>
+        public readonly ManagedEvent<EventArgsLocationBuildingsChanged> Location_BuildingsChanged;
 
-        /// <summary>Raised after the list of objects in a location changes (e.g. an object is added or removed).</summary>
+        /// <summary>Raised after objects are added or removed in a location.</summary>
         public readonly ManagedEvent<EventArgsLocationObjectsChanged> Location_ObjectsChanged;
 
         /****
@@ -160,6 +156,10 @@ namespace StardewModdingAPI.Framework.Events
         /// <summary> Raised after the player levels up a skill. This happens as soon as they level up, not when the game notifies the player after their character goes to bed.</summary>
         public readonly ManagedEvent<EventArgsLevelUp> Player_LeveledUp;
 
+        /// <summary>Raised after the player warps to a new location.</summary>
+        public readonly ManagedEvent<EventArgsPlayerWarped> Player_Warped;
+
+
         /****
         ** SaveEvents
         ****/
@@ -241,9 +241,8 @@ namespace StardewModdingAPI.Framework.Events
             this.Input_ButtonPressed = ManageEventOf<EventArgsInput>(nameof(InputEvents), nameof(InputEvents.ButtonPressed));
             this.Input_ButtonReleased = ManageEventOf<EventArgsInput>(nameof(InputEvents), nameof(InputEvents.ButtonReleased));
 
-            this.Location_CurrentLocationChanged = ManageEventOf<EventArgsCurrentLocationChanged>(nameof(LocationEvents), nameof(LocationEvents.CurrentLocationChanged));
-            this.Location_LocationsChanged = ManageEventOf<EventArgsGameLocationsChanged>(nameof(LocationEvents), nameof(LocationEvents.LocationsChanged));
-            this.Location_LocationObjectsChanged = ManageEventOf<EventArgsLocationObjectsChanged>(nameof(LocationEvents), nameof(LocationEvents.LocationObjectsChanged));
+            this.Location_LocationsChanged = ManageEventOf<EventArgsLocationsChanged>(nameof(LocationEvents), nameof(LocationEvents.LocationsChanged));
+            this.Location_BuildingsChanged = ManageEventOf<EventArgsLocationBuildingsChanged>(nameof(LocationEvents), nameof(LocationEvents.BuildingsChanged));
             this.Location_ObjectsChanged = ManageEventOf<EventArgsLocationObjectsChanged>(nameof(LocationEvents), nameof(LocationEvents.ObjectsChanged));
 
             this.Menu_Changed = ManageEventOf<EventArgsClickableMenuChanged>(nameof(MenuEvents), nameof(MenuEvents.MenuChanged));
@@ -258,6 +257,7 @@ namespace StardewModdingAPI.Framework.Events
 
             this.Player_InventoryChanged = ManageEventOf<EventArgsInventoryChanged>(nameof(PlayerEvents), nameof(PlayerEvents.InventoryChanged));
             this.Player_LeveledUp = ManageEventOf<EventArgsLevelUp>(nameof(PlayerEvents), nameof(PlayerEvents.LeveledUp));
+            this.Player_Warped = ManageEventOf<EventArgsPlayerWarped>(nameof(PlayerEvents), nameof(PlayerEvents.Warped));
 
             this.Save_BeforeCreate = ManageEvent(nameof(SaveEvents), nameof(SaveEvents.BeforeCreate));
             this.Save_AfterCreate = ManageEvent(nameof(SaveEvents), nameof(SaveEvents.AfterCreate));
diff --git a/src/SMAPI/Framework/SGame.cs b/src/SMAPI/Framework/SGame.cs
index d2ba85f8..c8c30834 100644
--- a/src/SMAPI/Framework/SGame.cs
+++ b/src/SMAPI/Framework/SGame.cs
@@ -23,7 +23,6 @@ using StardewValley.Menus;
 using StardewValley.Tools;
 using xTile.Dimensions;
 using xTile.Layers;
-using SObject = StardewValley.Object;
 
 namespace StardewModdingAPI.Framework
 {
@@ -92,11 +91,8 @@ namespace StardewModdingAPI.Framework
         /// <summary>Tracks changes to the save ID.</summary>
         private readonly IValueWatcher<ulong> SaveIdWatcher;
 
-        /// <summary>Tracks changes to the location list.</summary>
-        private readonly ICollectionWatcher<GameLocation> LocationListWatcher;
-
-        /// <summary>Tracks changes to each location.</summary>
-        private readonly IDictionary<GameLocation, LocationTracker> LocationWatchers = new Dictionary<GameLocation, LocationTracker>();
+        /// <summary>Tracks changes to the game's locations.</summary>
+        private readonly WorldLocationsTracker LocationsWatcher;
 
         /// <summary>Tracks changes to <see cref="Game1.activeClickableMenu"/>.</summary>
         private readonly IValueWatcher<IClickableMenu> ActiveMenuWatcher;
@@ -165,14 +161,14 @@ namespace StardewModdingAPI.Framework
             this.WindowSizeWatcher = WatcherFactory.ForEquatable(() => new Point(Game1.viewport.Width, Game1.viewport.Height));
             this.TimeWatcher = WatcherFactory.ForEquatable(() => Game1.timeOfDay);
             this.ActiveMenuWatcher = WatcherFactory.ForReference(() => Game1.activeClickableMenu);
-            this.LocationListWatcher = WatcherFactory.ForObservableCollection((ObservableCollection<GameLocation>)Game1.locations);
+            this.LocationsWatcher = new WorldLocationsTracker((ObservableCollection<GameLocation>)Game1.locations);
             this.Watchers.AddRange(new IWatcher[]
             {
                 this.SaveIdWatcher,
                 this.WindowSizeWatcher,
                 this.TimeWatcher,
                 this.ActiveMenuWatcher,
-                this.LocationListWatcher
+                this.LocationsWatcher
             });
         }
 
@@ -351,22 +347,7 @@ namespace StardewModdingAPI.Framework
                 foreach (IWatcher watcher in this.Watchers)
                     watcher.Update();
                 this.CurrentPlayerTracker?.Update();
-
-                // update location watchers
-                if (this.LocationListWatcher.IsChanged)
-                {
-                    foreach (GameLocation location in this.LocationListWatcher.Removed.Union(this.LocationListWatcher.Added))
-                    {
-                        if (this.LocationWatchers.TryGetValue(location, out LocationTracker watcher))
-                        {
-                            this.Watchers.Remove(watcher);
-                            this.LocationWatchers.Remove(location);
-                            watcher.Dispose();
-                        }
-                    }
-                    foreach (GameLocation location in this.LocationListWatcher.Added)
-                        this.LocationWatchers[location] = new LocationTracker(location);
-                }
+                this.LocationsWatcher.Update();
 
                 /*********
                 ** Locale changed events
@@ -516,45 +497,86 @@ namespace StardewModdingAPI.Framework
                 *********/
                 if (Context.IsWorldReady)
                 {
-                    // update player info
-                    PlayerTracker curPlayer = this.CurrentPlayerTracker;
+                    bool raiseWorldEvents = !this.SaveIdWatcher.IsChanged; // don't report changes from unloaded => loaded
 
-                    // raise current location changed
-                    if (curPlayer.TryGetNewLocation(out GameLocation newLocation))
+                    // raise location changes
+                    if (this.LocationsWatcher.IsChanged)
                     {
-                        if (this.VerboseLogging)
-                            this.Monitor.Log($"Context: set location to {newLocation.Name}.", LogLevel.Trace);
-                        this.Events.Location_CurrentLocationChanged.Raise(new EventArgsCurrentLocationChanged(curPlayer.LocationWatcher.PreviousValue, newLocation));
+                        // location list changes
+                        if (this.LocationsWatcher.IsLocationListChanged)
+                        {
+                            GameLocation[] added = this.LocationsWatcher.Added.ToArray();
+                            GameLocation[] removed = this.LocationsWatcher.Removed.ToArray();
+                            this.LocationsWatcher.ResetLocationList();
+
+                            if (this.VerboseLogging)
+                            {
+                                string addedText = this.LocationsWatcher.Added.Any() ? string.Join(", ", added.Select(p => p.Name)) : "none";
+                                string removedText = this.LocationsWatcher.Removed.Any() ? string.Join(", ", removed.Select(p => p.Name)) : "none";
+                                this.Monitor.Log($"Context: location list changed (added {addedText}; removed {removedText}).", LogLevel.Trace);
+                            }
+
+                            this.Events.Location_LocationsChanged.Raise(new EventArgsLocationsChanged(added, removed));
+                        }
+
+                        // raise location contents changed
+                        if (raiseWorldEvents)
+                        {
+                            foreach (LocationTracker watcher in this.LocationsWatcher.Locations)
+                            {
+                                // objects changed
+                                if (watcher.ObjectsWatcher.IsChanged)
+                                {
+                                    GameLocation location = watcher.Location;
+                                    var added = watcher.ObjectsWatcher.Added;
+                                    var removed = watcher.ObjectsWatcher.Removed;
+                                    watcher.ObjectsWatcher.Reset();
+
+                                    this.Events.Location_ObjectsChanged.Raise(new EventArgsLocationObjectsChanged(location, added, removed));
+                                }
+
+                                // buildings changed
+                                if (watcher.BuildingsWatcher.IsChanged)
+                                {
+                                    GameLocation location = watcher.Location;
+                                    var added = watcher.BuildingsWatcher.Added;
+                                    var removed = watcher.BuildingsWatcher.Removed;
+                                    watcher.BuildingsWatcher.Reset();
+
+                                    this.Events.Location_BuildingsChanged.Raise(new EventArgsLocationBuildingsChanged(location, added, removed));
+                                }
+                            }
+                        }
+                        else
+                            this.LocationsWatcher.Reset();
                     }
 
-                    // raise location list changed
-                    if (this.LocationListWatcher.IsChanged)
+                    // raise time changed
+                    if (raiseWorldEvents && this.TimeWatcher.IsChanged)
                     {
+                        int was = this.TimeWatcher.PreviousValue;
+                        int now = this.TimeWatcher.CurrentValue;
+                        this.TimeWatcher.Reset();
+
                         if (this.VerboseLogging)
-                        {
-                            string added = this.LocationListWatcher.Added.Any() ? string.Join(", ", this.LocationListWatcher.Added.Select(p => p.Name)) : "none";
-                            string removed = this.LocationListWatcher.Removed.Any() ? string.Join(", ", this.LocationListWatcher.Removed.Select(p => p.Name)) : "none";
-                            this.Monitor.Log($"Context: location list changed (added {added}; removed {removed}).", LogLevel.Trace);
-                        }
+                            this.Monitor.Log($"Context: time changed from {was} to {now}.", LogLevel.Trace);
 
-                        this.Events.Location_LocationsChanged.Raise(new EventArgsGameLocationsChanged(Game1.locations));
+                        this.Events.Time_TimeOfDayChanged.Raise(new EventArgsIntChanged(was, now));
                     }
+                    else
+                        this.TimeWatcher.Reset();
 
-                    // raise events that shouldn't be triggered on initial load
-                    if (!this.SaveIdWatcher.IsChanged)
+                    // raise player events
+                    if (raiseWorldEvents)
                     {
-                        // raise location objects changed
-                        foreach (LocationTracker watcher in this.LocationWatchers.Values)
-                        {
-                            if (watcher.LocationObjectsWatcher.IsChanged)
-                            {
-                                GameLocation location = watcher.Location;
-                                var added = watcher.LocationObjectsWatcher.Added;
-                                var removed = watcher.LocationObjectsWatcher.Removed;
-                                watcher.Reset();
+                        PlayerTracker curPlayer = this.CurrentPlayerTracker;
 
-                                this.Events.Location_ObjectsChanged.Raise(new EventArgsLocationObjectsChanged(location, added, removed, watcher.Location.netObjects.FieldDict));
-                            }
+                        // raise current location changed
+                        if (curPlayer.TryGetNewLocation(out GameLocation newLocation))
+                        {
+                            if (this.VerboseLogging)
+                                this.Monitor.Log($"Context: set location to {newLocation.Name}.", LogLevel.Trace);
+                            this.Events.Player_Warped.Raise(new EventArgsPlayerWarped(curPlayer.LocationWatcher.PreviousValue, newLocation));
                         }
 
                         // raise player leveled up a skill
@@ -574,27 +596,6 @@ namespace StardewModdingAPI.Framework
                             this.Events.Player_InventoryChanged.Raise(new EventArgsInventoryChanged(Game1.player.Items, changedItems.ToList()));
                         }
 
-                        // raise current location's object list changed
-                        {
-                            if (curPlayer.TryGetLocationChanges(out IDictionaryWatcher<Vector2, SObject> watcher))
-                            {
-                                if (this.VerboseLogging)
-                                    this.Monitor.Log("Context: current location objects changed.", LogLevel.Trace);
-
-                                GameLocation location = curPlayer.GetCurrentLocation();
-
-                                this.Events.Location_LocationObjectsChanged.Raise(new EventArgsLocationObjectsChanged(location, watcher.Added, watcher.Removed, location.netObjects.FieldDict));
-                            }
-                        }
-
-                        // raise time changed
-                        if (this.TimeWatcher.IsChanged)
-                        {
-                            if (this.VerboseLogging)
-                                this.Monitor.Log($"Context: time changed from {this.TimeWatcher.PreviousValue} to {this.TimeWatcher.CurrentValue}.", LogLevel.Trace);
-                            this.Events.Time_TimeOfDayChanged.Raise(new EventArgsIntChanged(this.TimeWatcher.PreviousValue, this.TimeWatcher.CurrentValue));
-                        }
-
                         // raise mine level changed
                         if (curPlayer.TryGetNewMineLevel(out int mineLevel))
                         {
@@ -603,18 +604,11 @@ namespace StardewModdingAPI.Framework
                             this.Events.Mine_LevelChanged.Raise(new EventArgsMineLevelChanged(curPlayer.MineLevelWatcher.PreviousValue, mineLevel));
                         }
                     }
+                    this.CurrentPlayerTracker?.Reset();
                 }
 
-                // update state
-                this.CurrentPlayerTracker?.Reset();
-                this.LocationListWatcher.Reset();
+                // update save ID watcher
                 this.SaveIdWatcher.Reset();
-                this.TimeWatcher.Reset();
-                if (!Context.IsWorldReady)
-                {
-                    foreach (LocationTracker watcher in this.LocationWatchers.Values)
-                        watcher.Reset();
-                }
 
                 /*********
                 ** Game update
diff --git a/src/SMAPI/Framework/StateTracking/FieldWatchers/NetCollectionWatcher.cs b/src/SMAPI/Framework/StateTracking/FieldWatchers/NetCollectionWatcher.cs
new file mode 100644
index 00000000..f92edb90
--- /dev/null
+++ b/src/SMAPI/Framework/StateTracking/FieldWatchers/NetCollectionWatcher.cs
@@ -0,0 +1,93 @@
+using System.Collections.Generic;
+using Netcode;
+
+namespace StardewModdingAPI.Framework.StateTracking.FieldWatchers
+{
+    /// <summary>A watcher which detects changes to a Netcode collection.</summary>
+    internal class NetCollectionWatcher<TValue> : BaseDisposableWatcher, ICollectionWatcher<TValue>
+        where TValue : INetObject<INetSerializable>
+    {
+        /*********
+        ** Properties
+        *********/
+        /// <summary>The field being watched.</summary>
+        private readonly NetCollection<TValue> Field;
+
+        /// <summary>The pairs added since the last reset.</summary>
+        private readonly List<TValue> AddedImpl = new List<TValue>();
+
+        /// <summary>The pairs demoved since the last reset.</summary>
+        private readonly List<TValue> RemovedImpl = new List<TValue>();
+
+
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>Whether the collection changed since the last reset.</summary>
+        public bool IsChanged => this.AddedImpl.Count > 0 || this.RemovedImpl.Count > 0;
+
+        /// <summary>The values added since the last reset.</summary>
+        public IEnumerable<TValue> Added => this.AddedImpl;
+
+        /// <summary>The values removed since the last reset.</summary>
+        public IEnumerable<TValue> Removed => this.RemovedImpl;
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="field">The field to watch.</param>
+        public NetCollectionWatcher(NetCollection<TValue> field)
+        {
+            this.Field = field;
+            field.OnValueAdded += this.OnValueAdded;
+            field.OnValueRemoved += this.OnValueRemoved;
+        }
+
+        /// <summary>Update the current value if needed.</summary>
+        public void Update()
+        {
+            this.AssertNotDisposed();
+        }
+
+        /// <summary>Set the current value as the baseline.</summary>
+        public void Reset()
+        {
+            this.AssertNotDisposed();
+
+            this.AddedImpl.Clear();
+            this.RemovedImpl.Clear();
+        }
+
+        /// <summary>Stop watching the field and release all references.</summary>
+        public override void Dispose()
+        {
+            if (!this.IsDisposed)
+            {
+                this.Field.OnValueAdded -= this.OnValueAdded;
+                this.Field.OnValueRemoved -= this.OnValueRemoved;
+            }
+
+            base.Dispose();
+        }
+
+
+        /*********
+        ** Private methods
+        *********/
+        /// <summary>A callback invoked when an entry is added to the collection.</summary>
+        /// <param name="value">The added value.</param>
+        private void OnValueAdded(TValue value)
+        {
+            this.AddedImpl.Add(value);
+        }
+
+        /// <summary>A callback invoked when an entry is removed from the collection.</summary>
+        /// <param name="value">The added value.</param>
+        private void OnValueRemoved(TValue value)
+        {
+            this.RemovedImpl.Add(value);
+        }
+    }
+}
diff --git a/src/SMAPI/Framework/StateTracking/FieldWatchers/WatcherFactory.cs b/src/SMAPI/Framework/StateTracking/FieldWatchers/WatcherFactory.cs
index bf261bb5..a4982faa 100644
--- a/