using System;
using System.Collections.Generic;
using System.IO;
using Autodesk.Revit.DB;
using Autodesk.Revit.DB.Analysis;

namespace Revit.SDK.Samples.NetworkPressureLossReport
{
   public class NetworkInfo
   {
      private Document m_doc;
      private string m_name;        // A recognizable name from design system or fabrication service.
      private double m_maxFlow;     // The maximum flow value of any segment on the entire network.
      private string m_flow;
      private ConnectorDomainType m_domainType;
      private IDictionary<int, SectionInfo> m_sections;

      public NetworkInfo(Document doc)
      {
         m_doc = doc;
         m_maxFlow = 0.0;
         m_flow = null;
         m_domainType = ConnectorDomainType.Undefined;
         m_sections = new SortedDictionary<int, SectionInfo>();
      }
      public int NumberOfSections
      {
         get { return m_sections.Count; }
      }
      public Document Document
      {
         get { return m_doc; }
      }
      public string Name
      {
         get { return m_name; }
         set { m_name = value; }
      }

      public string FlowDisplay
      {
         get { return m_flow; }
      }

      public ConnectorDomainType DomainType
      {
         get { return m_domainType; }
         set { m_domainType = value; }
      }

      public static IList<NetworkInfo> FindValidNetworks(Document doc)
      {
         IList<NetworkInfo> validNetworks = new List<NetworkInfo>();

         HashSet<MEPNetworkSegmentId> visitedSegments = new HashSet<MEPNetworkSegmentId>(new CompareNetworkSegmentId());

         // Find all elements that may drive the pipe or duct flow calculations.
         List<BuiltInCategory> categories = new List<BuiltInCategory>();
         categories.Add(BuiltInCategory.OST_MechanicalEquipment);
         categories.Add(BuiltInCategory.OST_PlumbingEquipment);
         categories.Add(BuiltInCategory.OST_DuctTerminal);

         ElementMulticategoryFilter multiCatFilter = new ElementMulticategoryFilter(categories);
         FilteredElementCollector elemCollector = new FilteredElementCollector(doc).WherePasses(multiCatFilter).WhereElementIsNotElementType();
         foreach (Element elem in elemCollector.ToElements())
         {
            MEPAnalyticalModelData data = MEPAnalyticalModelData.GetMEPAnalyticalModelData(elem);
            if (data == null)
               continue;

            int nSeg = data.GetNumberOfSegments();
            for (int ii = 0; ii < nSeg; ii++)
            {
               MEPAnalyticalSegment seg = data.GetSegmentByIndex(ii);
               MEPNetworkSegmentId idSegment = new MEPNetworkSegmentId(elem.Id, seg.Id);
               if (visitedSegments.Contains(idSegment))
                  continue;

               // Start from this analytical segment to traverse the entire network.
               NetworkInfo newNetwork = new NetworkInfo(doc);
               newNetwork.DomainType = seg.DomainType;

               // First start from the side of the start node.
               MEPAnalyticalNode startNode = data.GetNodeById(seg.StartNode);
               MEPNetworkIterator iter = new MEPNetworkIterator(doc, startNode, seg);
               for (iter.Start(); !iter.End(); iter.Next())
               {
                  MEPAnalyticalSegment currentSegment = iter.GetAnalyticalSegment();
                  if (currentSegment == null)
                     continue;

                  MEPAnalyticalModelData currentModelData = iter.GetAnalyticalModelData();
                  if (currentModelData == null)
                     continue;

                  // Mark this segment so not to create the duplicate network.
                  MEPNetworkSegmentId currentSegmentId = new MEPNetworkSegmentId(currentSegment.RevitElementId, currentSegment.Id);
                  visitedSegments.Add(currentSegmentId);

                  MEPNetworkSegmentData segFlowData = currentModelData.GetSegmentData(currentSegment.Id);
                  // Grow the network information by filling in one segment.
                  newNetwork.AddSegment(currentSegment, segFlowData);

                  // Refine the network name based on the straight segments.
                  if (currentSegment.SegmentType == MEPAnalyticalSegmentType.Segment)
                     newNetwork.RefineName(currentSegment.RevitElementId);
               }

               // If this is not a close loop, we must include the other side as well!
               MEPAnalyticalNode endNode = data.GetNodeById(seg.EndNode);
               iter = new MEPNetworkIterator(doc, endNode, seg);
               for (iter.Start(); !iter.End(); iter.Next())
               {
                  MEPAnalyticalSegment currentSegment = iter.GetAnalyticalSegment();
                  if (currentSegment == null)
                     continue;
                  MEPNetworkSegmentId currentSegmentId = new MEPNetworkSegmentId(currentSegment.RevitElementId, currentSegment.Id);
                  // Check if the segment was already visited.
                  if (visitedSegments.Contains(currentSegmentId))
                     continue;
                  visitedSegments.Add(currentSegmentId);

                  MEPAnalyticalModelData currentModelData = iter.GetAnalyticalModelData();
                  if (currentModelData == null)
                     continue;
                  MEPNetworkSegmentData segFlowData = currentModelData.GetSegmentData(currentSegment.Id);
                  newNetwork.AddSegment(currentSegment, segFlowData);
                  if (currentSegment.SegmentType == MEPAnalyticalSegmentType.Segment)
                     newNetwork.RefineName(currentSegment.RevitElementId);
               }

               // Collect this new network
               if (newNetwork.NumberOfSections > 0)
               {
                  newNetwork.ResetFlowDisplay();
                  validNetworks.Add(newNetwork);
               }
            }
         }
         return validNetworks;
      }

      public void AddSegment(MEPAnalyticalSegment segment, MEPNetworkSegmentData segmentData)
      {
         int sectionNumber = segmentData.SectionNumber;
         // The equipment segment may not belong to any section. Skip those?!
         if (sectionNumber < 0)
            return;

         double segmentFlow = Math.Abs(segmentData.Flow);
         if (segmentFlow > m_maxFlow)
            m_maxFlow = segmentFlow;

         if (!m_sections.ContainsKey(sectionNumber))
         {
            m_sections.Add(sectionNumber, new SectionInfo());
         }
         SegmentInfo newSegmentInfo = m_sections[sectionNumber].AddSegment(m_doc, segment, segmentData);
      }

      private void RefineName(ElementId idElem)
      {
         Element elem = m_doc.GetElement(idElem);
         MEPCurve aCurve = elem as MEPCurve;
         if (aCurve != null)
         {
            MEPSystem sys = aCurve.MEPSystem;
            if (sys != null)
            {
               AppendName(sys.Name);
            }
         }
         else
         {
            FabricationPart aPart = elem as FabricationPart;
            if (aPart != null)
            {
               string serviceName = aPart.ServiceName;
               // Get the full name of fabrication service by its id.
               FabricationConfiguration fabConfig = FabricationConfiguration.GetFabricationConfiguration(m_doc);
               if (fabConfig != null)
               {
                  FabricationService fabService = fabConfig.GetService(aPart.ServiceId);
                  if (fabService != null)
                  {
                     serviceName = fabService.Name;
                  }
               }
               AppendName(serviceName);
            }
         }
      }

      private void AppendName(string name)
      {
         if (string.IsNullOrEmpty(m_name))
         {
            m_name = name;
         }
         else
         {
            if (!m_name.Contains(name))
            {
               m_name += " + " + name;
            }
         }
      }
      private void ResetFlowDisplay()
      {
         ForgeTypeId specId = SpecTypeId.Flow;
         if (DomainType == ConnectorDomainType.Hvac)
            specId = SpecTypeId.AirFlow;

         // Reset the flow display value based on the maximum number after adding all segments.
         m_flow = UnitFormatUtils.Format(m_doc.GetUnits(), specId, m_maxFlow, false);
      }

      public void ExportCSV(CSVExporter ex)
      {
         // Export the header line.
         string str = string.Format("Section, Type/No, Element, Flow ({0}), Size/Hydraulic Diameter ({1}), Velocity ({2}), Velocity Pressure ({3}), Length ({4}), Coefficients, Friction ({5}), Pressure Loss ({3}), Section Pressure Loss ({3})", 
            ex.GetFlowUnitSymbol(), ex.GetSizeUnitSymbol(), ex.GetVelocityUnitSymbol(), ex.GetPressureUnitSymbol(), ex.GetLengthUnitSymbol(), ex.GetFrictionUnitSymbol());
         ex.Writer.WriteLine(str);
         foreach (var item in m_sections)
         {
            item.Value.ExportCSV(ex, item.Key);
         }
         // Critical path if available
         double dCriticalLoss = 0.0;
         string path = null;
         foreach(var item in m_sections)
         {
            if(item.Value.IsCriticalPath)
            {
               dCriticalLoss += item.Value.TotalPressureLoss;
               if(string.IsNullOrEmpty(path))
               {
                  path = item.Key.ToString();
               }
               else
               {
                  path += @" - " + item.Key.ToString();
               }
            }
         }
         ex.Writer.WriteLine(string.Format("Critical Pressure Loss: {0}, {1}", path, dCriticalLoss));
      }
      public void UpdateView(AVFViewer viewer)
      {
         List<XYZ> points = new List<XYZ>();
         List<VectorAtPoint> valList = new List<VectorAtPoint>();

         // Safety check.
         if (m_maxFlow < 0.0000001)
            return;

         foreach (var item in m_sections)
         {
            int sectionNum = item.Key;
            item.Value.UpdateView(viewer, points, valList, m_maxFlow);
         }

         if(points.Count > 0)
         {
            viewer.AddData(points, valList);
         }

      }
   }
}