using System.Collections.Generic;

using CoreNodeModels;

using Dynamo.Graph.Nodes;

using Dynamo.Utilities;

using ProtoCore.AST.AssociativeAST;

using Newtonsoft.Json;

namespace SampleLibraryUI.Examples

{

[NodeName("Drop Down Example")]

[NodeDescription("An example drop down node.")]

[IsDesignScriptCompatible]

public class DropDownExample : DSDropDownBase

{

public DropDownExample() : base("item"){}

// Starting with Dynamo v2.0 you must add Json constructors for all nodeModel

// derived nodes to support the move from an Xml to Json file format. Failing to

// do so will result in incorrect ports being generated upon serialization/deserialization.

// This constructor is called when opening a Json graph. We must also pass the deserialized

// ports with the json constructor and then call the base class passing the ports as parameters.

[JsonConstructor]

public DropDownExample(IEnumerable<PortModel> inPorts, IEnumerable<PortModel> outPorts) : base("item", inPorts, outPorts) { }

protected override SelectionState PopulateItemsCore(string currentSelection)

{

// The Items collection contains the elements

// that appear in the list. For this example, we

// clear the list before adding new items, but you

// can also use the PopulateItems method to add items

// to the list.

Items.Clear();

// Create a number of DynamoDropDownItem objects

// to store the items that we want to appear in our list.

var newItems = new List<DynamoDropDownItem>()

{

new DynamoDropDownItem("Tywin", 0),

new DynamoDropDownItem("Cersei", 1),

new DynamoDropDownItem("Hodor",2)

};

Items.AddRange(newItems);

// Set the selected index to something other

// than -1, the default, so that your list

// has a pre-selection.

SelectedIndex = 0;

return SelectionState.Restore;

}

public override IEnumerable<AssociativeNode> BuildOutputAst(List<AssociativeNode> inputAstNodes)

{

// Build an AST node for the type of object contained in your Items collection.

var intNode = AstFactory.BuildIntNode((int)Items[SelectedIndex].Item);

var assign = AstFactory.BuildAssignment(GetAstIdentifierForOutputIndex(0), intNode);

return new List<AssociativeNode> {assign};

}

}

}