checkpoint

Alpm/EnumerableWrapper`3.cs

@@ -1,17 +1,31 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Dynamic;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 
 namespace Foodsoft.Alpm
 {
-    internal struct EnumerableWrapper<TImpl, TElement, THandle> : IEnumerable<TElement> where TImpl : struct,
-        IItemsReader<TElement, THandle>
-        where THandle : SafeHandle
+    internal static class EnumerableWrapper<TElement>
+    {
+        internal static EnumerableWrapper<TElement, TImpl> Create<TImpl>(TImpl impl)
+            where TImpl : struct, ICollectionImpl<TElement>
+        {
+            return new EnumerableWrapper<TElement, TImpl>(impl);
+        }
+    }
+
+    internal struct EnumerableWrapper<TElement, TImpl> : ICollection<TElement> where TImpl : struct,
+        ICollectionImpl<TElement>
     {
         private TImpl _impl;
 
+        public static EnumerableWrapper<TElement, TImpl> Create(TImpl impl)
+        {
+            return new EnumerableWrapper<TElement, TImpl>(impl);
+        }
+
         public EnumerableWrapper(TImpl impl)
         {
             _impl = impl;
@@ -40,5 +54,67 @@ namespace Foodsoft.Alpm
         }
 
         IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+
+        public int Count
+        {
+            get
+            {
+                var impl = _impl;
+                return impl.Handle.UseHandle((_) => (int) alpm.alpm_list_count(impl.GetItems()));
+            }
+        }
+
+        public bool Contains(TElement item)
+        {
+            var impl = _impl;
+            switch (item)
+            {
+                case string s:
+                    return impl.Handle.UseHandle((_) => alpm.alpm_list_find_str(impl.GetItems(), s) != (IntPtr.Zero));
+                default:
+                    var comparer = EqualityComparer<TElement>.Default;
+                    return _impl.Handle.UseHandle((_) =>
+                    {
+                        for (var list = impl.GetItems(); list != IntPtr.Zero; list = Wrapper.ListNext(list))
+                        {
+                            if (comparer.Equals(item, impl.PtrToItem(Wrapper.ListData(list))))
+                                return true;
+                        }
+
+                        return false;
+                    });
+            }
+        }
+
+        public void CopyTo(TElement[] array, int arrayIndex)
+        {
+            var impl = _impl;
+            impl.Handle.UseHandle((_) =>
+            {
+                for (var list = impl.GetItems(); list != IntPtr.Zero; list = Wrapper.ListNext(list))
+                {
+                    array[arrayIndex++] = impl.PtrToItem(Wrapper.ListData(list));
+                }
+
+                return arrayIndex;
+            });
+        }
+
+        public void Add(TElement item)
+        {
+            throw new NotSupportedException();
+        }
+
+        public void Clear()
+        {
+            throw new NotSupportedException();
+        }
+
+        public bool Remove(TElement item)
+        {
+            throw new NotSupportedException();
+        }
+
+        public bool IsReadOnly => true;
     }
 }