Added the new ChestItemChanged event.

10 files changed, 200 insertions, 2 deletions

diff --git a/src/SMAPI.sln b/src/SMAPI.sln
index 62eaa777..65ea330c 100644
--- a/src/SMAPI.sln
+++ b/src/SMAPI.sln
@@ -1,7 +1,7 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio Version 16
-VisualStudioVersion = 16.0.28729.10
+# Visual Studio 15
+VisualStudioVersion = 15.0.28307.902
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = ".root", ".root", "{86C452BE-D2D8-45B4-B63F-E329EB06CEDA}"
 	ProjectSection(SolutionItems) = preProject
diff --git a/src/SMAPI/Events/ChestItemChangedEventArgs.cs b/src/SMAPI/Events/ChestItemChangedEventArgs.cs
new file mode 100644
index 00000000..6b06487c
--- /dev/null
+++ b/src/SMAPI/Events/ChestItemChangedEventArgs.cs
@@ -0,0 +1,47 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.Xna.Framework;
+using StardewValley;
+using Item = StardewValley.Item;
+
+namespace StardewModdingAPI.Events
+{
+    /// <summary>Event arguments for a <see cref="IWorldEvents.ChestItemChanged"/> event.</summary>
+    public class ChestItemChangedEventArgs : EventArgs
+    {
+        /*********
+        ** Accessors
+        *********/
+        /// <summary>The location which changed.</summary>
+        public GameLocation Location { get; }
+
+        /// <summary>The objects added to the location.</summary>
+        public IEnumerable<Item> Added { get; }
+
+        /// <summary>The objects removed from the location.</summary>
+        public IEnumerable<Item> Removed { get; }
+
+        /// <summary>The location of the chest from where the item was added or removed</summary>
+        public Vector2 LocationOfChest { get; }
+
+        /// <summary>Whether this is the location containing the local player.</summary>
+        public bool IsCurrentLocation => object.ReferenceEquals(this.Location, Game1.player?.currentLocation);
+
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="location">The location which changed.</param>
+        /// <param name="added">The objects added to the location.</param>
+        /// <param name="removed">The objects removed from the location.</param>
+        internal ChestItemChangedEventArgs(GameLocation location, IEnumerable<Item> added, IEnumerable<Item> removed, Vector2 locationOfChest)
+        {
+            this.Location = location;
+            this.Added = added.ToArray();
+            this.Removed = removed.ToArray();
+            this.LocationOfChest = locationOfChest;
+        }
+    }
+}
diff --git a/src/SMAPI/Events/IWorldEvents.cs b/src/SMAPI/Events/IWorldEvents.cs
index 0ceffcc1..6f9b71a7 100644
--- a/src/SMAPI/Events/IWorldEvents.cs
+++ b/src/SMAPI/Events/IWorldEvents.cs
@@ -23,6 +23,9 @@ namespace StardewModdingAPI.Events
         /// <summary>Raised after objects are added or removed in a location.</summary>
         event EventHandler<ObjectListChangedEventArgs> ObjectListChanged;
 
+        /// <summary>Raised after items are added or removed from a chest in a location.</summary>
+        event EventHandler<ChestItemChangedEventArgs> ChestItemChanged;
+
         /// <summary>Raised after terrain features (like floors and trees) are added or removed in a location.</summary>
         event EventHandler<TerrainFeatureListChangedEventArgs> TerrainFeatureListChanged;
     }
diff --git a/src/SMAPI/Framework/Events/EventManager.cs b/src/SMAPI/Framework/Events/EventManager.cs
index 18b00f69..dad45f95 100644
--- a/src/SMAPI/Framework/Events/EventManager.cs
+++ b/src/SMAPI/Framework/Events/EventManager.cs
@@ -148,6 +148,9 @@ namespace StardewModdingAPI.Framework.Events
         /// <summary>Raised after objects are added or removed in a location.</summary>
         public readonly ManagedEvent<ObjectListChangedEventArgs> ObjectListChanged;
 
+        /// <summary>Raised after a new item is added or removed from a chest in a location.</summary>
+        public readonly ManagedEvent<ChestItemChangedEventArgs> ChestItemsChanged;
+
         /// <summary>Raised after terrain features (like floors and trees) are added or removed in a location.</summary>
         public readonly ManagedEvent<TerrainFeatureListChangedEventArgs> TerrainFeatureListChanged;
 
@@ -221,6 +224,7 @@ namespace StardewModdingAPI.Framework.Events
             this.LocationListChanged = ManageEventOf<LocationListChangedEventArgs>(nameof(IModEvents.World), nameof(IWorldEvents.BuildingListChanged));
             this.NpcListChanged = ManageEventOf<NpcListChangedEventArgs>(nameof(IModEvents.World), nameof(IWorldEvents.NpcListChanged));
             this.ObjectListChanged = ManageEventOf<ObjectListChangedEventArgs>(nameof(IModEvents.World), nameof(IWorldEvents.ObjectListChanged));
+            this.ChestItemsChanged = ManageEventOf<ChestItemChangedEventArgs>(nameof(IModEvents.World), nameof(IWorldEvents.ChestItemChanged));
             this.TerrainFeatureListChanged = ManageEventOf<TerrainFeatureListChangedEventArgs>(nameof(IModEvents.World), nameof(IWorldEvents.TerrainFeatureListChanged));
 
             this.LoadStageChanged = ManageEventOf<LoadStageChangedEventArgs>(nameof(IModEvents.Specialized), nameof(ISpecializedEvents.LoadStageChanged));
diff --git a/src/SMAPI/Framework/Events/ModWorldEvents.cs b/src/SMAPI/Framework/Events/ModWorldEvents.cs
index b85002a3..8d6701ec 100644
--- a/src/SMAPI/Framework/Events/ModWorldEvents.cs
+++ b/src/SMAPI/Framework/Events/ModWorldEvents.cs
@@ -51,6 +51,12 @@ namespace StardewModdingAPI.Framework.Events
             remove => this.EventManager.ObjectListChanged.Remove(value);
         }
 
+        public event EventHandler<ChestItemChangedEventArgs> ChestItemChanged
+        {
+            add => this.EventManager.ChestItemsChanged.Add(value);
+            remove => this.EventManager.ChestItemsChanged.Remove(value);
+        }
+
         /// <summary>Raised after terrain features (like floors and trees) are added or removed in a location.</summary>
         public event EventHandler<TerrainFeatureListChangedEventArgs> TerrainFeatureListChanged
         {
diff --git a/src/SMAPI/Framework/SGame.cs b/src/SMAPI/Framework/SGame.cs
index 4774233e..564fec1d 100644
--- a/src/SMAPI/Framework/SGame.cs
+++ b/src/SMAPI/Framework/SGame.cs
@@ -702,6 +702,10 @@ namespace StardewModdingAPI.Framework
                                 if (locState.Objects.IsChanged)
                                     events.ObjectListChanged.Raise(new ObjectListChangedEventArgs(location, locState.Objects.Added, locState.Objects.Removed));
 
+                                // chest items changed
+                                if (locState.ChestItems.IsChanged)
+                                    events.ChestItemsChanged.Raise(new ChestItemChangedEventArgs(location, locState.ChestItems.Added, locState.ChestItems.Removed, locState.ChestItems.Key));
+
                                 // terrain features changed
                                 if (locState.TerrainFeatures.IsChanged)
                                     events.TerrainFeatureListChanged.Raise(new TerrainFeatureListChangedEventArgs(location, locState.TerrainFeatures.Added, locState.TerrainFeatures.Removed));
diff --git a/src/SMAPI/Framework/SnapshotListDiff.cs b/src/SMAPI/Framework/SnapshotListDiff.cs
index d4d5df50..b14cacdb 100644
--- a/src/SMAPI/Framework/SnapshotListDiff.cs
+++ b/src/SMAPI/Framework/SnapshotListDiff.cs
@@ -29,10 +29,18 @@ namespace StardewModdingAPI.Framework
         /// <summary>The added values.</summary>
         public IEnumerable<T> Added => this.AddedImpl;
 
+        public Microsoft.Xna.Framework.Vector2 Key;
 
         /*********
         ** Public methods
         *********/
+
+        public void Update(ICollectionWatcher<T> watcher, Microsoft.Xna.Framework.Vector2 key)
+        {
+            this.Key = key;
+            this.Update(watcher.IsChanged, watcher.Removed, watcher.Added);
+        }
+
         /// <summary>Update the snapshot.</summary>
         /// <param name="isChanged">Whether the value changed since the last update.</param>
         /// <param name="removed">The removed values.</param>
diff --git a/src/SMAPI/Framework/StateTracking/FieldWatchers/NetListWatcher.cs b/src/SMAPI/Framework/StateTracking/FieldWatchers/NetListWatcher.cs
new file mode 100644
index 00000000..cac66356
--- /dev/null
+++ b/src/SMAPI/Framework/StateTracking/FieldWatchers/NetListWatcher.cs
@@ -0,0 +1,100 @@
+using System;
+using System.Collections.Generic;
+using Netcode;
+
+namespace StardewModdingAPI.Framework.StateTracking.FieldWatchers
+{
+    internal class NetListWatcher<TKey, TValue> : BaseDisposableWatcher, ICollectionWatcher<TValue>
+        where TValue : class, INetObject<INetSerializable>
+    {
+
+
+        /*********
+        ** Fields
+        *********/
+        /// <summary>The field being watched.</summary>
+        private readonly NetList<TValue, Netcode.NetRef<TValue>> Field;
+
+        public TKey Key { get; }
+
+        /// <summary>The pairs added since the last reset.</summary>
+        private readonly IList<TValue> AddedImpl = new List<TValue>();
+
+        /// <summary>The pairs removed since the last reset.</summary>
+        private readonly IList<TValue> RemovedImpl = new List<TValue>();
+
+        /*********
+        ** Public methods
+        *********/
+        /// <summary>Construct an instance.</summary>
+        /// <param name="field">The field to watch.</param>
+        public NetListWatcher(NetList<TValue, Netcode.NetRef<TValue>> field, TKey key)
+        {
+            this.Field = field;
+            this.Key = key;
+            field.OnElementChanged += this.OnElementChanged;
+            field.OnArrayReplaced += this.OnArrayReplaced;
+        }
+
+        public bool IsChanged => this.AddedImpl.Count > 0 || this.RemovedImpl.Count > 0;
+
+        public IEnumerable<TValue> Added => this.AddedImpl;
+
+        public IEnumerable<TValue> Removed => this.RemovedImpl;
+
+        public void Dispose()
+        {
+            if (!this.IsDisposed)
+            {
+                this.Field.OnElementChanged -= this.OnElementChanged;
+                this.Field.OnArrayReplaced -= this.OnArrayReplaced;
+            }
+
+            base.Dispose();
+        }
+
+        public void Reset()
+        {
+            this.AddedImpl.Clear();
+            this.RemovedImpl.Clear();
+        }
+
+        public void Update()
+        {
+            this.AssertNotDisposed();
+        }
+
+        /*********
+        ** Private methods
+        *********/
+        private void OnArrayReplaced(NetList<TValue, Netcode.NetRef<TValue>> list, IList<TValue> before, IList<TValue> after)
+        {
+            this.AddedImpl.Clear();
+            this.RemovedImpl.Clear();
+
+            foreach(var obj in after)
+                this.AddedImpl.Add(obj);
+
+            foreach(var obj in before)
+                this.RemovedImpl.Add(obj);
+        }
+
+        private void OnElementChanged(NetList<TValue, Netcode.NetRef<TValue>> list, int index, TValue oldValue, TValue newValue)
+        {
+
+            /* checks for stack addition / subtraction changing stacks does not fire off an element changed event
+            if ((oldValue != null && newValue != null) && oldValue.CompareTo(newValue) < 0)
+                this.AddedImpl.Add(newValue);
+            //Stack Removed from
+            if ((oldValue != null && newValue != null) && oldValue.CompareTo(newValue) > 0)
+                this.RemovedImpl.Add(newValue);
+                */
+
+            if(newValue!=null)
+                this.AddedImpl.Add(newValue);
+
+            if(oldValue!=null)
+                this.RemovedImpl.Add(oldValue);
+        }
+    }
+}
diff --git a/src/SMAPI/Framework/StateTracking/LocationTracker.cs b/src/SMAPI/Framework/StateTracking/LocationTracker.cs
index 1f479e12..ef4a8b64 100644
--- a/src/SMAPI/Framework/StateTracking/LocationTracker.cs
+++ b/src/SMAPI/Framework/StateTracking/LocationTracker.cs
@@ -7,6 +7,7 @@ using StardewValley.Buildings;
 using StardewValley.Locations;
 using StardewValley.TerrainFeatures;
 using Object = StardewValley.Object;
+using Chest = StardewValley.Objects.Chest;
 
 namespace StardewModdingAPI.Framework.StateTracking
 {
@@ -47,6 +48,7 @@ namespace StardewModdingAPI.Framework.StateTracking
         /// <summary>Tracks added or removed terrain features.</summary>
         public IDictionaryWatcher<Vector2, TerrainFeature> TerrainFeaturesWatcher { get; }
 
+        public Dictionary<Vector2, NetListWatcher<Vector2, Item>> activeChestWatchers = new Dictionary<Vector2, NetListWatcher<Vector2, Item>>();
 
         /*********
         ** Public methods
@@ -88,6 +90,25 @@ namespace StardewModdingAPI.Framework.StateTracking
         {
             foreach (IWatcher watcher in this.Watchers)
                 watcher.Update();
+
+            foreach (KeyValuePair<Vector2, Object> obj in this.ObjectsWatcher.Added.Where(p => p.Value is Chest))
+            {
+                if (!this.activeChestWatchers.ContainsKey(obj.Key))
+                {
+                    //create a new watcher for chests items
+                    Chest temp = obj.Value as Chest;
+                    NetListWatcher<Vector2, Item> tempItemWatcher = new NetListWatcher<Vector2, Item>(temp.items, obj.Key);
+                    this.Watchers.Add(tempItemWatcher);
+                    this.activeChestWatchers.Add(obj.Key, tempItemWatcher);
+                }
+            }
+
+            foreach (KeyValuePair<Vector2, Object> obj in this.ObjectsWatcher.Removed)
+            {
+                this.activeChestWatchers.TryGetValue(obj.Key, out NetListWatcher<Vector2, Item> tempItemWatcher);
+                this.Watchers.Remove(tempItemWatcher);
+                this.activeChestWatchers.Remove(obj.Key);
+            } 
         }
 
         /// <summary>Set the current value as the baseline.</summary>
diff --git a/src/SMAPI/Framework/StateTracking/Snapshots/LocationSnapshot.cs b/src/SMAPI/Framework/StateTracking/Snapshots/LocationSnapshot.cs
index d3029540..31cf29c3 100644
--- a/src/SMAPI/Framework/StateTracking/Snapshots/LocationSnapshot.cs
+++ b/src/SMAPI/Framework/StateTracking/Snapshots/LocationSnapshot.cs
@@ -33,6 +33,8 @@ namespace StardewModdingAPI.Framework.StateTracking.Snapshots
         /// <summary>Tracks added or removed terrain features.</summary>
         public SnapshotListDiff<KeyValuePair<Vector2, TerrainFeature>> TerrainFeatures { get; } = new SnapshotListDiff<KeyValuePair<Vector2, TerrainFeature>>();
 
+        public SnapshotListDiff<Item> ChestItems { get; } = new SnapshotListDiff<Item>();
+
 
         /*********
         ** Public methods
@@ -54,6 +56,9 @@ namespace StardewModdingAPI.Framework.StateTracking.Snapshots
             this.Npcs.Update(watcher.NpcsWatcher);
             this.Objects.Update(watcher.ObjectsWatcher);
             this.TerrainFeatures.Update(watcher.TerrainFeaturesWatcher);
+
+            foreach (var obj in watcher.activeChestWatchers)
+                this.ChestItems.Update(obj.Value, obj.Key);
         }
     }
 }