using System;
using System.Collections.Generic;
using System.Linq;
using Autodesk.Revit.DB;
using KGdev.BI3D.Revit.Common;
using KGdev.BI3D.Revit.Common.Models;

namespace KGdev.BI3D.Revit.Implementations
{
    internal class DefaultLinkedDocumentUtilities : ILinkedDocumentsUtilities
    {
        public Element GetElement(Document rootDocument, LinkedElementIdPath path)
        {
            Document document = rootDocument;
            Queue<ElementId> queue = new Queue<ElementId>(path.ElementIds);
            Element element = null;
            while (queue.Count > 0)
            {
                ElementId elementId = queue.Dequeue();
                bool flag = queue.Count == 0;
                if (flag)
                {
                    element = document.GetElement(elementId);
                }
                else
                {
                    RevitLinkInstance revitLinkInstance =
                        document.GetElement(elementId) as RevitLinkInstance;
                    document = revitLinkInstance.GetLinkDocument();
                }
            }
            return element;
        }

        public IList<LinkedDocumentInformation> GetLinkedDocuments(
            Document rootDocument,
            Transform baseTransform,
            bool includeThis,
            List<ElementId> passedLinkInstanceIds
        )
        {
            List<LinkedDocumentInformation> list = new List<LinkedDocumentInformation>();
            if (includeThis)
            {
                list.Add(
                    new LinkedDocumentInformation
                    {
                        Document = rootDocument,
                        TransformToRoot = baseTransform,
                        PassedLinkInstanceIds = passedLinkInstanceIds
                    }
                );
            }
            IEnumerable<RevitLinkInstance> enumerable = new FilteredElementCollector(rootDocument)
                .OfCategory(BuiltInCategory.OST_RvtLinks)
                .OfClass(typeof(RevitLinkInstance))
                .Cast<RevitLinkInstance>();
            foreach (RevitLinkInstance revitLinkInstance in enumerable)
            {
                bool flag = !revitLinkInstance.IsValidObject;
                if (!flag)
                {
                    Document linkDocument = revitLinkInstance.GetLinkDocument();
                    bool flag2 = linkDocument == null || !linkDocument.IsValidObject;
                    if (!flag2)
                    {
                        Transform transform = baseTransform.Multiply(
                            revitLinkInstance.GetTransform()
                        );
                        List<ElementId> list2 = new List<ElementId>();
                        list2.AddRange(passedLinkInstanceIds);
                        list2.Add(revitLinkInstance.Id);
                        IList<LinkedDocumentInformation> linkedDocuments = this.GetLinkedDocuments(
                            linkDocument,
                            transform,
                            true,
                            list2
                        );
                        list.AddRange(linkedDocuments);
                    }
                }
            }
            return list;
        }
    }
}