using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.IO;
using System.Linq;
using System.Text;
using System.Windows.Controls;
using System.Windows.Media;
using AIStudio.Wpf.DiagramDesigner;
using AIStudio.Wpf.DiagramDesigner.Algorithms;
using AIStudio.Wpf.DiagramDesigner.Geometrys;
using AIStudio.Wpf.DiagramDesigner.Models;

namespace AIStudio.Wpf.Mind.ViewModels
{
    public class MindNode : DesignerItemViewModelBase
    {
        public MindNode(NodeLevel nodeLevel) : this(null, nodeLevel)
        {
        }

        public MindNode(IDiagramViewModel root, NodeLevel nodeLevel) : base(root)
        {
            NodeLevel = nodeLevel;
            LevelInit(true);
        }

        public MindNode(IDiagramViewModel root, SelectableItemBase designer) : base(root, designer)
        {
        }

        public MindNode(IDiagramViewModel root, SerializableItem serializableItem, string serializableType) : base(root, serializableItem, serializableType)
        {
        }

        protected override void Init(IDiagramViewModel root)
        {
            base.Init(root);

            EnabledForConnection = false;

            AddChildCommand = new SimpleCommand(Command_Enable, ExecuteAddChildCommand);
            AddParentCommand = new SimpleCommand(Level_Enable, ExecuteAddParentCommand);
            AddPeerCommand = new SimpleCommand(Level_Enable, ExecuteAddPeerCommand);
            DeleteCommand = new SimpleCommand(Level_Enable, ExecuteDeleteCommand);
            MoveForwardCommand = new SimpleCommand(Command_Enable, ExecuteMoveForwardCommand);
            MoveBackCommand = new SimpleCommand(Command_Enable, ExecuteMoveBackCommand);
            BuildMenuOptions();

            this.PropertyChanged += this.Item_PropertyChanged;
        }

        private void LevelInit(bool init = false)
        {
            switch (NodeLevel)
            {
                case NodeLevel.Level1:
                    {
                        ItemWidth = 110;
                        ItemHeight = 40;
                        this.ClearConnectors();
                        var port = new FullyCreatedConnectorInfo(Root, this, ConnectorOrientation.None, true) { XRatio = 0.5, YRatio = 0.5 };
                        this.AddConnector(port);
                        IsInnerConnector = true;

                        ColorViewModel.FillColor.Color = Color.FromRgb(0x73, 0xa1, 0xbf);
                        ColorViewModel.LineColor.Color = Color.FromRgb(0x73, 0xa1, 0xbf);
                        FontViewModel.FontColor = Colors.White;
                        FontViewModel.FontSize = 15;
                        Spacing = new SizeBase(50, 15);
                        ShapeViewModel.SinkMarker.PathStyle = ArrowPathStyle.Circle;
                        ShapeViewModel.SinkMarker.SizeStyle = ArrowSizeStyle.VerySmall;

                        break;
                    }
                case NodeLevel.Level2:
                    {
                        ItemWidth = 80;
                        ItemHeight = 25;
                        this.ClearConnectors();
                        var port1 = new FullyCreatedConnectorInfo(Root, this, ConnectorOrientation.Left, true) { XRatio = 0, YRatio = 0.5 };
                        this.AddConnector(port1);
                        var port2 = new FullyCreatedConnectorInfo(Root, this, ConnectorOrientation.Right, true) { XRatio = 1, YRatio = 0.5 };
                        this.AddConnector(port2);
                        IsInnerConnector = true;

                        ColorViewModel.LineColor.Color = Color.FromRgb(0x73, 0xa1, 0xbf);
                        ShapeViewModel.SinkMarker.PathStyle = ArrowPathStyle.None;
                        ShapeViewModel.SinkMarker.SizeStyle = ArrowSizeStyle.VerySmall;
                        break;
                    }
                case NodeLevel.Level3:
                    {
                        ItemWidth = 80;
                        ItemHeight = 25;
                        this.ClearConnectors();
                        var port1 = new FullyCreatedConnectorInfo(Root, this, ConnectorOrientation.Left, true) { XRatio = 0, YRatio = 1 };
                        this.AddConnector(port1);
                        var port2 = new FullyCreatedConnectorInfo(Root, this, ConnectorOrientation.Right, true) { XRatio = 1, YRatio = 1 };
                        this.AddConnector(port2);
                        IsInnerConnector = true;

                        ColorViewModel.LineColor.Color = Color.FromRgb(0x73, 0xa1, 0xbf);
                        ShapeViewModel.SinkMarker.PathStyle = ArrowPathStyle.None;
                        ShapeViewModel.SinkMarker.SizeStyle = ArrowSizeStyle.VerySmall;
                        break;
                    }
            }
        }

        private bool Level_Enable(object obj)
        {
            if (Command_Enable(obj) == false) return false;

            return NodeLevel != NodeLevel.Level1;
        }

        #region 属性
        [Browsable(false)]
        private NodeLevel _nodeLevel;
        public NodeLevel NodeLevel
        {
            get
            {
                return _nodeLevel;
            }
            set
            {
                SetProperty(ref _nodeLevel, value);
            }
        }

        private double _cornerRadius = 3;
        public double CornerRadius
        {
            get
            {
                return _cornerRadius;
            }
            set
            {
                SetProperty(ref _cornerRadius, value);
            }
        }

        private bool _isExpanded = true;
        public bool IsExpanded
        {
            get
            {
                return _isExpanded;
            }
            set
            {
                SetProperty(ref _isExpanded, value);
            }
        }   

        public SizeBase Spacing
        {
            get; set;
        } = new SizeBase(15, 15);

        public List<MindNode> Children
        {
            get; set;
        } = new List<MindNode>();

        public SizeBase SizeWithSpacing
        {
            get
            {
                return this.Size.Add(Spacing.Width * 2, Spacing.Height * 2);
            }
        }

        public SizeBase DesiredSize
        {
            get; set;
        }

        public PointBase DesiredPosition
        {
            get; set;
        }

        public PointBase Offset
        {
            get; set;
        }

        private MindType _mindType;
        public MindType MindType
        {
            get
            {
                return _mindType;
            }
            set
            {
                SetProperty(ref _mindType, value);
            }
        }

        private bool _layoutUpdating;

        private bool _isRightLayout = true;
        #endregion

        #region 命令
        public SimpleCommand AddParentCommand
        {
            get; private set;
        }

        public SimpleCommand AddChildCommand
        {
            get; private set;
        }

        public SimpleCommand AddPeerCommand
        {
            get; private set;
        }

        public SimpleCommand DeleteCommand
        {
            get; private set;
        }

        public SimpleCommand MoveForwardCommand
        {
            get; private set;
        }

        public SimpleCommand MoveBackCommand
        {
            get; private set;
        }
        #endregion

        #region 菜单
        private void BuildMenuOptions()
        {
            menuOptions = new ObservableCollection<CinchMenuItem>();
            CinchMenuItem menuItem = new CinchMenuItem();
            menuItem.Text = "下级";
            menuItem.Command = AddChildCommand;
            menuOptions.Add(menuItem);
            menuItem = new CinchMenuItem();
            menuItem.Text = "同级";
            menuItem.Command = AddPeerCommand;
            menuOptions.Add(menuItem);
            menuItem = new CinchMenuItem();
            menuItem.Text = "上级";
            menuItem.Command = AddParentCommand;
            menuOptions.Add(menuItem);
            menuItem = new CinchMenuItem();
            menuItem.Text = "前移";
            menuItem.Command = MoveForwardCommand;
            menuOptions.Add(menuItem);
            menuItem = new CinchMenuItem();
            menuItem.Text = "后移";
            menuItem.Command = MoveBackCommand;
            menuOptions.Add(menuItem);
            menuItem = new CinchMenuItem();
            menuItem.Text = "删除";
            menuItem.Command = DeleteCommand;
            menuOptions.Add(menuItem);
        }
        #endregion

        #region 操作
        public void ExecuteAddChildCommand(object obj)
        {
            if (obj is MindNode node)
            {
            }
            else
            {
                if (NodeLevel == NodeLevel.Level1)
                    node = new MindNode(Root, NodeLevel.Level2) { Text = "分支主题" };
                else
                    node = new MindNode(Root, NodeLevel.Level3) { Text = "分支主题" };
            }
            AddChild(node);

            LayoutUpdated();
        }

        public void ExecuteAddParentCommand(object obj)
        {
            if (Parent is MindNode parent)
            {
                if (obj is MindNode node)
                {
                }
                else
                {
                    if (NodeLevel == NodeLevel.Level1)
                    {
                        return;
                    }
                    else if (NodeLevel == NodeLevel.Level2)
                        node = new MindNode(Root, NodeLevel.Level2) { Text = "分支主题" };
                    else
                        node = new MindNode(Root, NodeLevel.Level3) { Text = "分支主题" };
                }

                parent.RemoveChild(this);
                int index = parent.Children.IndexOf(this);
                parent.AddChild(node, index + 1);

                node.AddChild(this);

                LayoutUpdated();
            }
        }

        public void ExecuteAddPeerCommand(object obj)
        {
            if (Parent is MindNode parent)
            {
                if (obj is MindNode node)
                {
                }
                else
                {
                    if (NodeLevel == NodeLevel.Level1)
                    {
                        return;
                    }
                    else if (NodeLevel == NodeLevel.Level2)
                        node = new MindNode(Root, NodeLevel.Level2) { Text = "分支主题" };
                    else
                        node = new MindNode(Root, NodeLevel.Level3) { Text = "分支主题" };
                }
                int index = parent.Children.IndexOf(this);
                parent.AddChild(node, index + 1);

                LayoutUpdated();
            }
        }

        private void ExecuteMoveBackCommand(object obj)
        {
            if (Parent is MindNode parent)
            {
                int index = parent.Children.IndexOf(this);
                if (index < parent.Children.Count - 1)
                {
                    parent.RemoveChild(this);
                    parent.AddChild(this, index + 1);
                    LayoutUpdated();
                }
            }
        }

        private void ExecuteMoveForwardCommand(object obj)
        {
            if (Parent is MindNode parent)
            {
                int index = parent.Children.IndexOf(this);
                if (index > 0)
                {
                    parent.RemoveChild(this);
                    parent.AddChild(this, index - 1);
                    LayoutUpdated();
                }
            }
        }

        private void ExecuteDeleteCommand(object obj)
        {
            if (Parent is MindNode parent)
            {
                parent.RemoveChild(this, true);
                LayoutUpdated();
            }
        }

        public void AddChild(MindNode item, int index = -1)
        {
            if (this.NodeLevel == NodeLevel.Level1)
            {
                item.NodeLevel = NodeLevel.Level2;
            }
            else
            {
                item.NodeLevel = NodeLevel.Level3;
            }
            if (index >= 0)
            {
                this.Children.Insert(index, item);
            }
            else
            {
                this.Children.Add(item);
            }
            item.Parent = this;
            Root?.DirectAddItemCommand.Execute(item);

            ConnectionViewModel connector = new ConnectionViewModel(Root, this.Connectors.FirstOrDefault(), item.Connectors.FirstOrDefault());
            connector.ColorViewModel.LineColor = this.ColorViewModel.LineColor;
            connector.SmoothMargin = 20;
            connector.SmoothAutoSlope = 0.2;
            connector.ShapeViewModel.SinkMarker.PathStyle = this.ShapeViewModel.SinkMarker.PathStyle;
            connector.ShapeViewModel.SinkMarker.SizeStyle = this.ShapeViewModel.SinkMarker.SizeStyle;

            Root?.DirectAddItemCommand.Execute(connector);
            Root?.ClearSelectedItemsCommand.Execute(new SelectableDesignerItemViewModelBase[] { connector });

            Root?.BringForwardCommand.Execute(new DesignerItemViewModelBase[] { item });
        }

        public void RemoveChild(MindNode item, bool removeall = false)
        {
            item.PropertyChanged -= Item_PropertyChanged;

            this.Children.Remove(item);

            var connectors = Root?.Items.OfType<ConnectionViewModel>().Where(p => p.SinkConnectorInfoFully?.DataItem == item).ToList();

            Root?.DirectRemoveItemCommand.Execute(item);
            Root?.DirectRemoveItemCommand.Execute(connectors);

            if (removeall)
            {
                if (item.Children?.Count > 0)
                {
                    foreach (var child in item.Children.ToList())
                    {
                        item.RemoveChild(child);
                    }
                }
            }
        }
        #endregion

        private void Item_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            switch (e.PropertyName)
            {
                case nameof(IsExpanded):
                case nameof(ItemWidth):
                case nameof(ItemHeight):
                case nameof(MindType):
                    GetLevel1Node()?.LayoutUpdated();
                    break;
                case nameof(NodeLevel):
                    LevelInit();
                    break;
                case nameof(Left):
                    {
                        if (e is ValuePropertyChangedEventArgs valuePropertyChangedEventArgs)
                        {
                            if (NodeLevel == NodeLevel.Level1)
                            {
                                LayoutUpdated();
                            }
                            else
                            {
                                UpdateOffsetX((double)valuePropertyChangedEventArgs.OldValue, (double)valuePropertyChangedEventArgs.NewValue);
                                LayoutUpdated();
                            }
                        }
                        break;
                    }
                case nameof(Top):
                    {
                        if (e is ValuePropertyChangedEventArgs valuePropertyChangedEventArgs)
                        {
                            if (NodeLevel == NodeLevel.Level1)
                            {
                                LayoutUpdated();
                            }
                            else
                            {
                                UpdateOffsetY((double)valuePropertyChangedEventArgs.OldValue, (double)valuePropertyChangedEventArgs.NewValue);
                                LayoutUpdated();
                            }
                        }
                        break;
                    }
            }
        }

        #region 布局相关
        protected MindNode GetLevel1Node()
        {
            var node = this;
            while (node.Parent is MindNode mindNode)
            {
                node = mindNode;
            }
            return node;
        }

        protected MindNode GetLevel2Node()
        {
            var node = this;
            while (node.Parent is MindNode mindNode && mindNode.NodeLevel == NodeLevel.Level2)
            {
                node = mindNode;
            }
            return node;
        }

        protected void UpdateOffsetX(double oldvalue, double newvalue)
        {
            if (GetLevel1Node()?._layoutUpdating == true) return;

            Offset += new VectorBase(newvalue - oldvalue, 0);
        }

        protected void UpdateOffsetY(double oldvalue, double newvalue)
        {
            if (GetLevel1Node()?._layoutUpdating == true) return;

            Offset += new VectorBase(0, newvalue - oldvalue);
        }

        public void LayoutUpdated()
        {
            GetLevel1Node()?.Level1LayoutUpdated();
        }

        protected void Level1LayoutUpdated()
        {
            _layoutUpdating = true;
            var size = MeasureOverride();
            ArrangeOverride();

            Root.BringToFrontCommand.Execute(new SelectableDesignerItemViewModelBase[] { this });
            Root?.ReconnectLinksToClosestPorts();

            _layoutUpdating = false;
        }

        protected SizeBase MeasureOverride(bool isExpanded = true)
        {
            switch (MindType)
            {
                case MindType.Mind:
                    {
                        var sizewithSpacing = SizeWithSpacing;
                        if (Children?.Count > 0)
                        {
                            if (NodeLevel == NodeLevel.Level1)
                            {
                                var rights = Children.Where((p, index) => index % 2 == 0).ToList();
                                rights.ForEach(p => p._isRightLayout = true);
                                var rightsizes = rights.Select(p => p.MeasureOverride(IsExpanded && isExpanded)).ToArray();

                                var lefts = Children.Where((p, index) => index % 2 == 1).ToList();
                                lefts.ForEach(p => p._isRightLayout = false);
                                var leftsizes = lefts.Select(p => p.MeasureOverride(IsExpanded && isExpanded)).ToArray();
                                sizewithSpacing = new SizeBase(sizewithSpacing.Width + rightsizes.Max(p => p.Width) + +leftsizes.Max(p => p.Width), Math.Max(sizewithSpacing.Height, Math.Max(rightsizes.Sum(p => p.Height), leftsizes.Sum(p => p.Height))));
                            }
                            else
                            {
                                var childrensizes = Children.Select(p => p.MeasureOverride(IsExpanded && isExpanded)).ToArray();
                                sizewithSpacing = new SizeBase(sizewithSpacing.Width + childrensizes.Max(p => p.Width), Math.Max(sizewithSpacing.Height, childrensizes.Sum(p => p.Height)));
                            }
                        }
                        DesiredSize = isExpanded ? sizewithSpacing : new SizeBase(0, 0);
                        Visible = isExpanded;
                        var connectors = Root?.Items.OfType<ConnectionViewModel>().Where(p => p.SinkConnectorInfoFully?.DataItem == this).ToList();
                        connectors?.ForEach(p => p.Visible = Visible);
                        break;
                    }
                case MindType.Logical:
                    {
                        var sizewithSpacing = SizeWithSpacing;
                        if (Children?.Count > 0)
                        {
                            var childrensizes = Children.Select(p => p.MeasureOverride(IsExpanded && isExpanded)).ToArray();
                            sizewithSpacing = new SizeBase(sizewithSpacing.Width + childrensizes.Max(p => p.Width), Math.Max(sizewithSpacing.Height, childrensizes.Sum(p => p.Height)));
                        }
                        DesiredSize = isExpanded ? sizewithSpacing : new SizeBase(0, 0);
                        Visible = isExpanded;
                        var connectors = Root?.Items.OfType<ConnectionViewModel>().Where(p => p.SinkConnectorInfoFully?.DataItem == this).ToList();
                        connectors?.ForEach(p => p.Visible = Visible);
                        break;
                    }
                default:
                    {
                        var sizewithSpacing = SizeWithSpacing;
                        if (Children?.Count > 0)
                        {
                            var childrensizes = Children.Select(p => p.MeasureOverride(IsExpanded && isExpanded)).ToArray();
                            sizewithSpacing = new SizeBase(sizewithSpacing.Width + childrensizes.Max(p => p.Width), Math.Max(sizewithSpacing.Height, childrensizes.Sum(p => p.Height)));
                        }
                        DesiredSize = isExpanded ? sizewithSpacing : new SizeBase(0, 0);
                        Visible = isExpanded;
                        var connectors = Root?.Items.OfType<ConnectionViewModel>().Where(p => p.SinkConnectorInfoFully?.DataItem == this).ToList();
                        connectors?.ForEach(p => p.Visible = Visible);
                        break;
                    }
            }
            return DesiredSize;
        }

        protected void ArrangeOverride()
        {
            switch (MindType)
            {
                case MindType.Mind:
                    {
                        if (NodeLevel == NodeLevel.Level1)
                        {
                            if (Children?.Count > 0)
                            {
                                var rights = Children.Where(p => p._isRightLayout == true).ToList();
                                double left = MiddlePosition.X + ItemWidth / 2 + Spacing.Width;
                                double lefttop = MiddlePosition.Y - Math.Min(DesiredSize.Height, rights.Sum(p => p.DesiredSize.Height)) / 2;
                                foreach (var child in rights)
                                {
                                    child.Left = left + child.Spacing.Width + child.Offset.X;
                                    child.Top = lefttop + child.DesiredSize.Height / 2 - child.ItemHeight / 2 + child.Offset.Y;
                                    child.DesiredPosition = child.Position;
                                    lefttop += child.DesiredSize.Height;

                                    child.ArrangeOverride();
                                }

                                var lefts = Children.Where(p => p._isRightLayout == false).ToList();
                                double right = MiddlePosition.X - ItemWidth / 2 - Spacing.Width;
                                double righttop = MiddlePosition.Y - Math.Min(DesiredSize.Height, lefts.Sum(p => p.DesiredSize.Height)) / 2;                              
                                foreach (var child in lefts)
                                {
                                    child.Left = right - child.Spacing.Width - child.ItemWidth + child.Offset.X ;
                                    child.Top = righttop + child.DesiredSize.Height / 2 - child.ItemHeight / 2 + child.Offset.Y;
                                    child.DesiredPosition = child.Position;
                                    righttop += child.DesiredSize.Height;

                                    child.ArrangeOverride();
                                }
                            }
                        }
                        else
                        {
                            if (GetLevel2Node()._isRightLayout)
                            {
                                double left = MiddlePosition.X + ItemWidth / 2 + Spacing.Width;
                                double top = MiddlePosition.Y - Math.Min(DesiredSize.Height, Children.Sum(p => p.DesiredSize.Height)) / 2;
                                if (Children?.Count > 0)
                                {
                                    foreach (var child in Children)
                                    {
                                        child.Left = left + child.Spacing.Width + child.Offset.X;
                                        child.Top = top + child.DesiredSize.Height / 2 - child.ItemHeight / 2 + child.Offset.Y;
                                        child.DesiredPosition = child.Position;
                                        top += child.DesiredSize.Height;

                                        child.ArrangeOverride();
                                    }
                                }
                            }
                            else
                            {
                                double right = MiddlePosition.X - ItemWidth / 2 - Spacing.Width;
                                double top = MiddlePosition.Y - Math.Min(DesiredSize.Height, Children.Sum(p => p.DesiredSize.Height)) / 2;
                                if (Children?.Count > 0)
                                {
                                    foreach (var child in Children)
                                    {
                                        child.Left = right - child.Spacing.Width - child.ItemWidth + child.Offset.X;
                                        child.Top = top + child.DesiredSize.Height / 2 - child.ItemHeight / 2 + child.Offset.Y;
                                        child.DesiredPosition = child.Position;
                                        top += child.DesiredSize.Height;

                                        child.ArrangeOverride();
                                    }
                                }
                            }
                        }
                        break;
                    }
                case MindType.Logical:
                    {
                        double left = MiddlePosition.X + ItemWidth / 2 + Spacing.Width;
                        double top = MiddlePosition.Y - Math.Min(DesiredSize.Height, Children.Sum(p => p.DesiredSize.Height)) / 2;
                        if (Children?.Count > 0)
                        {
                            foreach (var child in Children)
                            {
                                child.Left = left + child.Spacing.Width + child.Offset.X;
                                child.Top = top + child.DesiredSize.Height / 2 - child.ItemHeight / 2 + child.Offset.Y;
                                child.DesiredPosition = child.Position;
                                top += child.DesiredSize.Height;

                                child.ArrangeOverride();
                            }
                        }
                        break;
                    }
                default:
                    {
                        break;
                    }
            }
        }
        #endregion
    }
}