refactor and cleanup [skip ci]

submodules/Postbox/Sources/ItemCollection.swift

@@ -0,0 +1,107 @@
+import Foundation
+
+public struct ItemCollectionId: Comparable, Hashable {
+    public typealias Namespace = Int32
+    public typealias Id = Int64
+    
+    public let namespace: ItemCollectionId.Namespace
+    public let id: ItemCollectionId.Id
+    
+    public init(namespace: ItemCollectionId.Namespace, id: ItemCollectionId.Id) {
+        self.namespace = namespace
+        self.id = id
+    }
+    
+    public static func ==(lhs: ItemCollectionId, rhs: ItemCollectionId) -> Bool {
+        return lhs.namespace == rhs.namespace && lhs.id == rhs.id
+    }
+    
+    public static func <(lhs: ItemCollectionId, rhs: ItemCollectionId) -> Bool {
+        if lhs.namespace == rhs.namespace {
+            return lhs.id < rhs.id
+        } else {
+            return lhs.namespace < rhs.namespace
+        }
+    }
+    
+    public var hashValue: Int {
+        return self.id.hashValue
+    }
+    
+    public static func encodeArrayToBuffer(_ array: [ItemCollectionId], buffer: WriteBuffer) {
+        var length: Int32 = Int32(array.count)
+        buffer.write(&length, offset: 0, length: 4)
+        for id in array {
+            var idNamespace = id.namespace
+            buffer.write(&idNamespace, offset: 0, length: 4)
+            var idId = id.id
+            buffer.write(&idId, offset: 0, length: 8)
+        }
+    }
+    
+    public static func decodeArrayFromBuffer(_ buffer: ReadBuffer) -> [ItemCollectionId] {
+        var length: Int32 = 0
+        memcpy(&length, buffer.memory, 4)
+        buffer.offset += 4
+        var i = 0
+        var array: [ItemCollectionId] = []
+        array.reserveCapacity(Int(length))
+        while i < Int(length) {
+            var idNamespace: Int32 = 0
+            buffer.read(&idNamespace, offset: 0, length: 4)
+            var idId: Int64 = 0
+            buffer.read(&idId, offset: 0, length: 8)
+            array.append(ItemCollectionId(namespace: idNamespace, id: idId))
+            i += 1
+        }
+        return array
+    }
+}
+
+public protocol ItemCollectionInfo: PostboxCoding {
+    
+}
+
+public struct ItemCollectionItemIndex: Comparable, Hashable {
+    public typealias Index = Int32
+    public typealias Id = Int64
+    
+    public let index: ItemCollectionItemIndex.Index
+    public let id: ItemCollectionItemIndex.Id
+    
+    public init(index: ItemCollectionItemIndex.Index, id: ItemCollectionItemIndex.Id) {
+        self.index = index
+        self.id = id
+    }
+    
+    public static func ==(lhs: ItemCollectionItemIndex, rhs: ItemCollectionItemIndex) -> Bool {
+        return lhs.index == rhs.index && lhs.id == rhs.id
+    }
+    
+    public static func <(lhs: ItemCollectionItemIndex, rhs: ItemCollectionItemIndex) -> Bool {
+        if lhs.index == rhs.index {
+            return lhs.id < rhs.id
+        } else {
+            return lhs.index < rhs.index
+        }
+    }
+    
+    static var lowerBound: ItemCollectionItemIndex {
+        return ItemCollectionItemIndex(index: 0, id: 0)
+    }
+    
+    static var upperBound: ItemCollectionItemIndex {
+        return ItemCollectionItemIndex(index: Int32.max, id: Int64.max)
+    }
+}
+
+public protocol ItemCollectionItem: PostboxCoding {
+    var index: ItemCollectionItemIndex { get }
+    var indexKeys: [MemoryBuffer] { get }
+}
+
+public enum ItemCollectionSearchQuery {
+    case exact(ValueBoxKey)
+    case matching([ValueBoxKey])
+    case any([ValueBoxKey])
+}