Line items update

MVMCore/MVMCore/Models/Model/ModelRegistry.swift

@@ -75,22 +75,7 @@ extension KeyedDecodingContainer where Key: CodingKey {
         guard var container = try? nestedUnkeyedContainer(forKey: codingKey) else {
             return nil
         }
-        var models = [Model]()
+        return try container.decodeModelsIfPresent(typeCodingKey: typeCodingKey)
-        var containerCopy = container
-        while !container.isAtEnd {
-            let nestedContainer = try container.nestedContainer(keyedBy: TypeKey.self)
-            if let identifier = try nestedContainer.decodeIfPresent(String.self, forKey: typeCodingKey) {
-                //get the type
-                guard let type = ModelRegistry.getType(for: identifier) else {
-                    throw ModelRegistry.Error.decoderErrorModelNotMapped
-                }
-                //now get the decoder to use for the type
-                let decoder = try containerCopy.superDecoder()
-                let model = try type.init(from: decoder)
-                models.append(model)
-            }
-        }
-        return models
     }
 
     /// Decodes an array of registered model based on the identifiers.
@@ -100,6 +85,22 @@ extension KeyedDecodingContainer where Key: CodingKey {
         }
         return models
     }
+    
+    /// Decodes an array with arrays of models based on the identifiers, optional.
+    public func decodeModels2DIfPresent<TypeKey: CodingKey>(codingKey: KeyedDecodingContainer<K>.Key, typeCodingKey: TypeKey) throws -> [[Model]]? {
+        guard var container = try? nestedUnkeyedContainer(forKey: codingKey) else {
+            return nil
+        }
+        return try container.decodeModels2DIfPresent(typeCodingKey: typeCodingKey)
+    }
+    
+    /// Decodes an array with arrays of models based on the identifiers.
+    public func decodeModels2D<TypeKey: CodingKey>(codingKey: KeyedDecodingContainer<K>.Key, typeCodingKey: TypeKey) throws -> [[Model]] {
+        guard let models: [[Model]] = try decodeModels2DIfPresent(codingKey: codingKey, typeCodingKey: typeCodingKey) else {
+            throw ModelRegistry.Error.decoderErrorObjectNotPresent
+        }
+        return models
+    }
 }
 
 extension KeyedEncodingContainer where Key: CodingKey {
@@ -131,4 +132,52 @@ extension KeyedEncodingContainer where Key: CodingKey {
             try model.encode(unkeyedContainer: &unkeyedContainer)
         }
     }
+    
+    /// Convenience function for encoding the container into a list of lists of Models. needs instance type as input paramaeter list
+    public mutating func encodeModels2D(_ list: [[Model]]?, forKey key:KeyedEncodingContainer<K>.Key) throws {
+        guard let list = list else { return }
+        var unkeyedContainer = self.nestedUnkeyedContainer(forKey: key)
+        for models in list {
+            var arrayunkeyedContainer = unkeyedContainer.nestedUnkeyedContainer()
+            for model in models {
+                try model.encode(unkeyedContainer: &arrayunkeyedContainer)
+            }
+        }
+    }
+}
+
+extension UnkeyedDecodingContainer {
+    /// Decodes the container into a list of Models.
+    public mutating func decodeModelsIfPresent<TypeKey: CodingKey>(typeCodingKey: TypeKey) throws -> [Model]? {
+        var models = [Model]()
+        var containerCopy = self
+        while !containerCopy.isAtEnd {
+            let nestedContainer = try containerCopy.nestedContainer(keyedBy: TypeKey.self)
+            if let identifier = try nestedContainer.decodeIfPresent(String.self, forKey: typeCodingKey) {
+                //get the type
+                guard let type = ModelRegistry.getType(for: identifier) else {
+                    throw ModelRegistry.Error.decoderErrorModelNotMapped
+                }
+                //now get the decoder to use for the type
+                let decoder = try self.superDecoder()
+                let model = try type.init(from: decoder)
+                models.append(model)
+            }
+        }
+        return models
+    }
+    
+    /// Convenience function for decoding the container into a list of lists of Models.
+    public mutating func decodeModels2DIfPresent<TypeKey: CodingKey>(typeCodingKey: TypeKey) throws -> [[Model]]? {
+        var modelLists = [[Model]]()
+        var containerCopy = self
+        while !containerCopy.isAtEnd {
+            var arraycontainerCopy = try containerCopy.nestedUnkeyedContainer()
+            guard let models = try arraycontainerCopy.decodeModelsIfPresent(typeCodingKey: typeCodingKey) else {
+                throw ModelRegistry.Error.decoderErrorModelNotMapped
+            }
+            modelLists.append(models)
+        }
+        return modelLists
+    }
 }