openscad-graph-editor

using System.Collections.Generic;
using System.Linq;
using Godot;
using GodotExt;
using OpenScadGraphEditor.Library;
using OpenScadGraphEditor.Library.IO;
using OpenScadGraphEditor.Utils;

namespace OpenScadGraphEditor.Nodes
{
    /// <summary>
    /// A function invocation.
    /// </summary>
    public class FunctionInvocation : ScadNode, IAmAnExpression, IReferToAFunction
    {
        private FunctionDescription _description;
        public override string NodeTitle => _description.NodeNameOrFallback;
        public override string NodeQuickLookup => _description.QuickNodeLookup;
        public override string NodeDescription => _description.Description;

        public InvokableDescription InvokableDescription => _description;

        public override void SaveInto(SavedNode node)
        {
            base.SaveInto(node);
            node.SetData("function_description_id", _description.Id);
        }


        public override string GetPortDocumentation(PortId portId)
        {
            if (portId.IsInput)
            {
                return _description.Parameters[portId.Port].Description;
            }

            if (portId.IsOutput)
            {
                return _description.ReturnValueDescription;
            }

            return "";
        }

        public int GetParameterInputPort(int parameterIndex)
        {
            // as function invocations have no flow ports, the n-th parameter port is the n-th input port.
            return parameterIndex;
        }
        

        public int GetParameterOutputPort(int parameterIndex)
        {
            // function invocations have no output ports corresponding to the parameters.
            return -1;
        }

        public IEnumerable<PortId> GetPortsReferringToReturnValue()
        {
            // function invocation does not have a port for the return value
            return Enumerable.Empty<PortId>();
        }

        public override void RestorePortDefinitions(SavedNode node, IReferenceResolver referenceResolver)
        {
            var functionDescriptionId = node.GetDataString("function_description_id");
            SetupPorts(referenceResolver.ResolveFunctionReference(functionDescriptionId));
            base.RestorePortDefinitions(node, referenceResolver);
        }

        public void SetupPorts(InvokableDescription description)
        {
            GdAssert.That(description is FunctionDescription, "Needs a function description");
            InputPorts.Clear();
            OutputPorts.Clear();
            
            _description = (FunctionDescription) description;

            foreach (var parameter in _description.Parameters)
            {
                var type = parameter.TypeHint;
                InputPorts
                    .PortType(type, parameter.LabelOrFallback, type.GetMatchingLiteralType(), !parameter.IsOptional,
                        renderHint: parameter.RenderHint);
            }

            OutputPorts
                    .PortType( _description.ReturnTypeHint);
        }

        public override string Render(ScadGraph context, int portIndex)
        {
           var parameters = _description.Parameters.Count.Range()
                .Select(it =>
                {
                    var parameterDescription = _description.Parameters[it];
                    var value = RenderInput(context, it);
                    return value.Empty() && parameterDescription.IsOptional
                        ? ""
                        : $"{parameterDescription.Name} = {value.OrUndef()}";
                })
                .Where(it => !it.Empty())
                .JoinToString(", ");
            
            return $"{_description.Name}({parameters})";
        }
    }
}