using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows;
using System.Windows.Documents;
using System.Windows.Input;
using System.Collections.ObjectModel;
using System.IO;
using RSG.SceneXml;
using RSG.Base.ConfigParser;
using System.ComponentModel;


namespace LODBrowserSystem
{
    public static class ContentMapNodeExtensions
    {
        //Gets the SceneXmlFilePath for the ContentNodeMap
        public static String GetSceneXmlFilePath(this ContentNodeMap Target)
        {
            //Get the ContentNodeMapZip for out InputContentNodeMap
            ContentNodeMapZip TargetContentMapNodeZip;
            if (Target.HasOutputContentNode())
            {
                TargetContentMapNodeZip = Target.Outputs[0] as ContentNodeMapZip;
            }
            else
            {
                return null; //No valid outputs so return null
            }

            //Derive our SceneXML path and return it
            return Path.GetFullPath((Path.Combine(TargetContentMapNodeZip.Path, Target.Name + ".xml")));
        }

        //Returns true if the passed ContentNodeMap has some output nodes set
        public static Boolean HasOutputContentNode(this ContentNodeMap Target)
        {
            if (Target.Outputs.Count() > 0)
            { return true; }
            else
            { return false; }
        }
    }

    public class DelegateCommand : ICommand
    {
        Action<Object> _ExecuteDelegate;

        public DelegateCommand(Action<Object> ExecuteDelegate)
        {
            _ExecuteDelegate = ExecuteDelegate;
        }

        public void Execute(Object Parameter)
        {
            _ExecuteDelegate(Parameter);
        }

        public bool CanExecute(Object parameter) { return true; }
        public event EventHandler CanExecuteChanged;
    }

    public class LODObjectEventArgs : EventArgs
    {
        public LODObject[] TargetLODObjects { get; set; }

        public LODObjectEventArgs(LODObject[] InputLODObjects)
        {
            this.TargetLODObjects = InputLODObjects;
        }
    }

    public class LODBrowser : INotifyPropertyChanged
    {
        public LODBrowser()
        {
            _ConfigGameView = new ConfigGameView();
            _ContentModel = _ConfigGameView.Content;

            ContainerLodContentNameList = (from ContentNodeMap SubContentNodeMap
                                            in _ConfigGameView.Content.Root.FindAll("map")
                                           where SubContentNodeMap.MapType == ContentNodeMap.MapSubType.ContainerLod
                                           select SubContentNodeMap.Name).ToArray();

            //Register events for the scene xml background worker
            _SceneXMLWorker.DoWork += this.SceneXMLWorker_StartWork;
            _SceneXMLWorker.RunWorkerCompleted += this.SceneXMLWorker_CompletedWork;
            _SceneXMLWorker.ProgressChanged += new ProgressChangedEventHandler(SceneXMLWorker_ProgressChanged);

            //Create our merge command
            this.Command_MergeLODObjects = new DelegateCommand(o =>
            {
                if (TargetLODContainer != null)
                {
                    LODObject[] TargetLODObjects = TargetLODContainer.GetLODObjectsForMerge();
                    RaiseRequestMergeLODObjects(TargetLODObjects);
                }
            });

        }

        //Binds the incoming view to this view model by setting the data context of the view to this 
        //instance of LODBrowserTool and setting up and adding attached event listeners.
        FrameworkElement _ViewRootElement;
        public void BindView(FrameworkElement InputViewRootElement)
        {
            this._ViewRootElement = InputViewRootElement;

            //Set data context
            this._ViewRootElement.DataContext = this;
        }

        //Command for merging LODObjects into a max scene
        public DelegateCommand Command_MergeLODObjects { get; private set; }

        //Event to signal that the tool wants to merge some LODObjects
        public event EventHandler<LODObjectEventArgs> RequestMergeLODObjects = delegate { };
        void RaiseRequestMergeLODObjects(LODObject[] TargetLODObjects)
        {
            RequestMergeLODObjects(this, new LODObjectEventArgs(TargetLODObjects));
        }

        //Background worker for reading large amounts of Scene .xml files
        readonly BackgroundWorker _SceneXMLWorker = new BackgroundWorker { WorkerReportsProgress = true };

        ConfigGameView _ConfigGameView;
        ContentModel _ContentModel;

        //Content name of all the lod containers in the content model
        public String[] ContainerLodContentNameList { get; set; }

        //Property which lets the UI know if the system is available to switch to another container lod
        public Boolean _WorkerAvailable = true;
        public Boolean WorkerAvailable
        {
            get { return _WorkerAvailable; }
            set
            {
                _WorkerAvailable = value;
                RaisePropertyChanged("WorkerAvailable");
            }
        }

        //Selected ContainerLod content name
        String _SelectedContainerLodContentName;
        public String SelectedContainerLodContentName
        {
            get { return _SelectedContainerLodContentName; }
            set
            {
                _SelectedContainerLodContentName = value;

                //Get the target ContentNodeMap object - this will be of type ContainerLod
                ContentNodeMap TargetContentNodeMap = _ContentModel.Root.FindFirst(_SelectedContainerLodContentName) as ContentNodeMap;

                //Get the scene xml file path for all sibliing ContentNodeMap objects of type Container or ContainerProps
                var SceneXmlFilePaths = (from ContentNodeMap SourceContentMapNode in (TargetContentNodeMap.Parent as ContentNodeGroup).Children
                                         where SourceContentMapNode.MapType == ContentNodeMap.MapSubType.Container ||
                                                  SourceContentMapNode.MapType == ContentNodeMap.MapSubType.ContainerProps &&
                                                  SourceContentMapNode.HasOutputContentNode()
                                         select SourceContentMapNode.GetSceneXmlFilePath()).ToArray();

                //Process the list so it only contains scene xml file paths which haven't yet been cached
                SceneXmlFilePaths = LODContainer.ProcessSceneXMLFilePaths(SceneXmlFilePaths);

                //Cache the require scene xml files in the background.
                _SceneXMLWorker.RunWorkerAsync(SceneXmlFilePaths);

                //Set that the worker is now unavailable. Stops us despatching multiple container lod requests.
                WorkerAvailable = false;

                //Raise property changed
                RaisePropertyChanged("SelectedContainerLodContentName");
            }
        }

        //The loaded LODContainer
        LODContainer _TargetLODContainer;
        public LODContainer TargetLODContainer
        {
            get { return _TargetLODContainer; }
            set
            {
                _TargetLODContainer = value;
                RaisePropertyChanged("TargetLODContainer");
            }
        }

        //Current progress value for reading SceneXml files
        Double _LoadProgressValue = 0.0;
        public Double LoadProgressValue
        {
            get { return _LoadProgressValue; }
            set
            {
                _LoadProgressValue = value;
                RaisePropertyChanged("LoadProgressValue");
            }
        }

        // Declare the PropertyChanged event
        public event PropertyChangedEventHandler PropertyChanged;

        // NotifyPropertyChanged will raise the PropertyChanged event passing the
        // source property that is being updated.
        public void RaisePropertyChanged(String PropertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(PropertyName));
            }
        }

        //Event handler for when the SceneXMLWorker is asked to start work
        void SceneXMLWorker_StartWork(object sender, DoWorkEventArgs e)
        {
            //Get the files to be processed and based off this get percentage step value
            var SceneXMLFilePathArray = e.Argument as String[];
            Double PercentageStep = 100.0 / SceneXMLFilePathArray.Count();
            Double CurrentPercentage = 0.0;

            //Load each of the scene def
            List<Scene> ReturnSceneDefList = new List<Scene>();
            foreach (var SceneXMLFilePath in SceneXMLFilePathArray)
            {
                ReturnSceneDefList.Add(Scene.Load(SceneXMLFilePath, LoadOptions.Objects, false));
                _SceneXMLWorker.ReportProgress((Int32)(CurrentPercentage += PercentageStep));
            }

            //Set our result to the collected SceneDef objects
            e.Result = ReturnSceneDefList;
        }

        //Event handler for when the SceneXMLWorker has finsihed it's current batch of work
        void SceneXMLWorker_CompletedWork(object sender, RunWorkerCompletedEventArgs e)
        {
            //Get our result and append it to our cached SceneDefs
            List<Scene> SceneDefListResult = e.Result as List<Scene>;
            LODContainer.SceneDefList.AddRange(SceneDefListResult);

            //Get the target ContentNodeMap object - this will be of type ContainerLod
            ContentNodeMap TargetContentNodeMap = _ContentModel.Root.FindFirst(_SelectedContainerLodContentName) as ContentNodeMap;
            TargetLODContainer = new LODContainer(TargetContentNodeMap);

            //Set that the work completed this operation so is now available again
            WorkerAvailable = true;
        }

        //Event handler for when the SceneXMLWorker posts an increase in progress
        void SceneXMLWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
        {
            this.LoadProgressValue = e.ProgressPercentage;
        }
    }

    public class LODContainer
    {
        //The source content node for the LOD container
        ContentNodeMap SourceContentNodeMap;

        //Cache of SceneDef objects
        public static List<Scene> SceneDefList = new List<Scene>();

        //Resolves a scene def from the passed ContentNodeMap. Essentially it tries to find one in our 
        //cache and if it fails to find it will try to create a new one.
        public static Scene ResolveSceneDef(ContentNodeMap InputContentNodeMap)
        {
            //Get the SceneDef from our cache (if it exists)
            var SceneDef = (from CachedSceneDef in SceneDefList
                            where CachedSceneDef.Filename == InputContentNodeMap.GetSceneXmlFilePath()
                            select CachedSceneDef).FirstOrDefault();


            //If we didn't find one in the cache then we'll make a new one
            if (SceneDef == null)
            {
                if (InputContentNodeMap.HasOutputContentNode())
                {
                    SceneDef = Scene.Load(InputContentNodeMap.GetSceneXmlFilePath(), LoadOptions.Objects, false);

                    //If it's valid then add it into our cache.
                    if (SceneDef != null)
                    {
                        SceneDefList.Add(SceneDef);
                    }
                }
            }

            return SceneDef;
        }

        //Processes and returns an array of scene xml file path strings which haven't yet been cached
        public static String[] ProcessSceneXMLFilePaths(String[] InputSceneXMLFilePaths)
        {
            //Get all currently cached scene xml file paths
            var CachedSceneXMLFilePaths = from CachedSceneDef in SceneDefList select CachedSceneDef.Filename;

            //Get all the uncached scene xml file paths by doing a comparison against the cached list
            var ValidSceneXMLFilePaths = from InputSceneXMLFilePath in InputSceneXMLFilePaths
                                         where CachedSceneXMLFilePaths.Contains(InputSceneXMLFilePath) == false
                                         select InputSceneXMLFilePath;

            return ValidSceneXMLFilePaths.ToArray();
        }

        //A handle to all of the LOD objects related to this LOD container
        List<LODObject> LODObjectList = new List<LODObject>();

        //The root LODObjects (SLOD3 - in theory) related to this container.
        public ObservableCollection<LODObject> RootLODObjects { get; set; }

        public LODContainer(ContentNodeMap InputContentNodeMap)
        {
            this.SourceContentNodeMap = InputContentNodeMap;
            this.RootLODObjects = new ObservableCollection<LODObject>();

            //Process the scene xml for the LOD container first
            ProcessContentMapNode(this.SourceContentNodeMap);

            //Fill out our root LODObjects. These are objects in the LODContainer that have 
            //no parent so are at the top of the heirarchy. Or in other words they 
            //are SLOD3 (or should be at least)
            foreach (var SubLODObject in LODObjectList)
            {
                if (SubLODObject.LODParent == null)
                {
                    RootLODObjects.Add(SubLODObject);
                }
            }

            //Then we load in the scene xml for every source content node and processing the SceneXML.
            //This should file out the remaining information.
            foreach (ContentNodeMap SubSourceContentNodeMap in (SourceContentNodeMap.Parent as ContentNodeGroup).Children)
            {
                ProcessContentMapNode(SubSourceContentNodeMap);
            }
        }

        //Takes an ObjectDef as input and returns a LODObject which wraps the ObjectDef
        LODObject ResolveLODObject(TargetObjectDef InputObjectDef, ContentNodeMap InputContentNodeMap)
        {
            //If the ObjectDef is a rscontainerlodref we'll dig into our LODObject list and try and find a match by a name
            if (InputObjectDef.Class == "rscontainerlodref")
            {
                if (InputObjectDef.ParamBlocks.Count() > 0)
                {
                    String TargetObjectName;
                    if (InputObjectDef.ParamBlocks[0].ContainsKey("objectname"))
                    {
                        TargetObjectName = InputObjectDef.ParamBlocks[0]["objectname"] as String;
                    }
                    else
                    { return null; }  //If we don't have an object name param then there is likely something wrong with the data.


                    //Now try and get the target LODObject from the TargetObjectName
                    var MatchingLODObject = (from QueryLODObject in LODObjectList
                                             where String.Compare(QueryLODObject.SourceObjectDef.Name, TargetObjectName, true) == 0
                                             select QueryLODObject).FirstOrDefault();

                    return MatchingLODObject;
                }
                else { return null; } //If we don't have any params blocks then something is likely wrong with data.
            }
            else
            {
                //Find our LODObject by objectdef. If we fail to find one we make one.
                var MatchingLODObject = (from QueryLODObject in LODObjectList
                                         where QueryLODObject.SourceObjectDef.Guid == InputObjectDef.Guid
                                         select QueryLODObject).FirstOrDefault();
                if (MatchingLODObject == null)
                {
                    MatchingLODObject = new LODObject(InputObjectDef, InputContentNodeMap);
                    LODObjectList.Add(MatchingLODObject);
                }

                return MatchingLODObject;
            }
        }

        //Process LOD information from the passed ContentMapNode.
        void ProcessContentMapNode(ContentNodeMap InputContentNodeMap)
        {
            //first we'll check that we are passing in a valid ContentNodeMap
            if (InputContentNodeMap.MapType == ContentNodeMap.MapSubType.Container ||
                InputContentNodeMap.MapType == ContentNodeMap.MapSubType.ContainerProps ||
                InputContentNodeMap.MapType == ContentNodeMap.MapSubType.ContainerLod)
            {
                //Get our scene def
                var SceneDef = ResolveSceneDef(InputContentNodeMap);

                //If the sceneDef doesn't have any children then we'll return and do nothing
                if (SceneDef == null || SceneDef.Objects.Count() != 1 || SceneDef.Objects[0].Children.Count() == 0)
                {
                    return;
                }

                //Go through all the root level object defs looking for objects which have some lod hierarchy information
                foreach (var RootLevelObjectDef in SceneDef.Objects[0].Children)
                {
                    //If we have some LOD information we'll act on it
                    if (RootLevelObjectDef.LOD != null)
                    {
                        //Get the LOD object for this ObjectDef
                        var TargetLODObject = ResolveLODObject(RootLevelObjectDef, InputContentNodeMap);

                        //If the ObjectDef has a parent then process it
                        if (RootLevelObjectDef.LOD.Parent != null)
                        {
                            var ParentLODObject = ResolveLODObject(RootLevelObjectDef.LOD.Parent, InputContentNodeMap);
                            TargetLODObject.LODParent = ParentLODObject;
                        }

                        //If the ObjectDef has any children we'll process them as well
                        foreach (var LODChildObjectDef in RootLevelObjectDef.LOD.Children)
                        {
                            var ChildLODObject = ResolveLODObject(LODChildObjectDef, InputContentNodeMap);
                            TargetLODObject.AddChildLODObject(ChildLODObject);
                        }
                    }
                }
            }
        }

        internal LODObject[] GetLODObjectsForMerge()
        {
            return (from SubLODObject in LODObjectList where SubLODObject.MarkedForMerge select SubLODObject).ToArray();
        }
    }

    public class LODObject : INotifyPropertyChanged
    {
        //Source ContentNodeMap that this LODObject comes from
        public ContentNodeMap SourceContentNodeMap { get; private set; }

        //Source ObjectDef this LODObject wraps
        public TargetObjectDef SourceObjectDef { get; private set; }

        //Source art file (.maxc) for the LODObject
        public String SourceFilePath
        {
            get { return Path.Combine(SourceContentNodeMap.Path, SourceContentNodeMap.Name + ".maxc"); }
        }

        //Source container name
        public String SourceContainerName
        {
            get { return SourceContentNodeMap.Name; }
        }

        //Source object name
        public String SourceObjectName
        {
            get { return SourceObjectDef.Name; }
        }

        //Source transform of object
        public RSG.Base.Math.Matrix34f SourceObjectTransform
        {
            get { return SourceObjectDef.NodeTransform; }
        }

        //Parent LODObject. Can only have one parent
        public LODObject LODParent { get; set; }

        //Children LODObjects.
        public List<LODObject> LODChildren { get; set; }

        //Returns true if the LODObject has children
        public Boolean HasChildren
        {
            get { return LODChildren.Count > 0; }
        }

        //Indicates if the object is marked for merge
        Boolean _MarkedForMerge = false;
        public Boolean MarkedForMerge
        {
            get { return _MarkedForMerge; }
            set
            {
                _MarkedForMerge = value;
                RaisePropertyChanged("MarkedForMerge");
            }
        }

        // Declare the PropertyChanged event
        public event PropertyChangedEventHandler PropertyChanged;

        // NotifyPropertyChanged will raise the PropertyChanged event passing the
        // source property that is being updated.
        public void RaisePropertyChanged(String PropertyName)
        {
            if (PropertyChanged != null)
            {
                PropertyChanged(this, new PropertyChangedEventArgs(PropertyName));
            }
        }

        //Checks that the passed LODObject hasn't already been added as a child - adds it if need be.
        internal void AddChildLODObject(LODObject InputLODObject)
        {
            if (!LODChildren.Contains(InputLODObject))
            {
                LODChildren.Add(InputLODObject);
            }
        }

        //Primary constuctor for a LOD object
        public LODObject(TargetObjectDef InputSourceObjectDef, ContentNodeMap InputContentNodeMap)
        {
            this.SourceObjectDef = InputSourceObjectDef;
            this.SourceContentNodeMap = InputContentNodeMap;

            this.LODChildren = new List<LODObject>();

            //Setup commands
            this.Command_MarkDirectChildren = new DelegateCommand(o => { MarkChildrenForMerge(false); });
            this.Command_MarkAllChildren = new DelegateCommand(o => { MarkChildrenForMerge(true); });
        }

        //Marks children for merge. Recurses if passed true.
        void MarkChildrenForMerge(Boolean Recursive)
        {
            foreach (var ChildLODObject in this.LODChildren)
            {
                ChildLODObject.MarkedForMerge = true;

                if (Recursive)
                {
                    ChildLODObject.MarkChildrenForMerge(Recursive);
                }
            }
        }

        //Command for marking direct child LODObjects for merge
        public DelegateCommand Command_MarkDirectChildren { get; private set; }

        //Command for marking all child LODObjects for merge
        public DelegateCommand Command_MarkAllChildren { get; private set; }

        //Returns a display friendly name for the LODObject
        public String HeaderString
        {
            get { return String.Format("{0} [{1}]", SourceObjectDef.Name, SourceContentNodeMap.Name); }
        }

    }

}