using Godot;
using System.Diagnostics;
using System.Linq;
using Array = Godot.Collections.Array;

public class Game : Spatial
{
    // ui elements
    private Label _framesPerSecondLabel;
    private Label _centerLabel;
    private Label _tileOffsetLabel;
    private Label _numTilesLabel;
    private Label _mouseWorldLabel;
    private Label _mouseTileOffsetLabel;
    private Label _mouseTileCubeLabel;
    private Label _numCoordsAddedLabel;
    private Label _numCoordsRemovedLabel;
    private TextureRect _worldTextureRect;
    private TextureRect _heightTextureRect;
    private Button _generateWorldButton;
    private Control _gameUi;
    private Label _goldCountLabel;

    // scene nodes
    private Spatial _tileHighlight;
    private Spatial _mouseTileHighlight;
    private StreamContainer _streamContainer;
    private Area _streamContainerArea;
    private Spatial _streamContainerActiveTiles;
    private Player _player;
    private TileWorld _tileWorld;
    private Camera _camera;

    // Resources
    private PackedScene _tileHighlightScene;
    private ShaderMaterial _tileMaterial;

    // other members
    private HexGrid _hexGrid;
    private HexCell _lastTile;
    private HexCell _currentTile;
    private Vector3 _cameraOffset;
    private ImageTexture _blackWhitePatternTexture;
    private InteractionSystem _interactionSystem;

    // Called when the node enters the scene tree for the first time.
    public override void _Ready()
    {
        // debugStatsContainer
        Container debugStatsContainer = (Container)FindNode("DebugStatsContainer");

        _framesPerSecondLabel = debugStatsContainer.GetNode<Label>("fps_label");
        _centerLabel = debugStatsContainer.GetNode<Label>("center_label");
        _tileOffsetLabel = debugStatsContainer.GetNode<Label>("tile_offset_label");
        _numTilesLabel = debugStatsContainer.GetNode<Label>("num_tiles_label");
        _mouseWorldLabel = debugStatsContainer.GetNode<Label>("mouse_world_label");
        _mouseTileOffsetLabel = debugStatsContainer.GetNode<Label>("mouse_tile_offset_label");
        _mouseTileCubeLabel = debugStatsContainer.GetNode<Label>("mouse_tile_cube_label");
        _numCoordsAddedLabel = debugStatsContainer.GetNode<Label>("num_coords_added_label");
        _numCoordsRemovedLabel = debugStatsContainer.GetNode<Label>("num_coords_removed_label");

        // UI elements
        Container worldGeneratorContainer = (Container)FindNode("WorldGeneratorContainer");
        _worldTextureRect = worldGeneratorContainer.GetNode<TextureRect>("WorldTextureRect");
        _heightTextureRect = worldGeneratorContainer.GetNode<TextureRect>("HeightTextureRect");
        _generateWorldButton = worldGeneratorContainer.GetNode<Button>("WorldGenerateButton");
        _gameUi = (Control)FindNode("GameUI");
        _goldCountLabel = _gameUi.GetNode<Label>("GoldCount");
        Debug.Assert(_goldCountLabel != null);

        // scene nodes
        _tileHighlight = GetNode<Spatial>("TileHighlight");
        _mouseTileHighlight = GetNode<Spatial>("MouseTileHighlight");

        _streamContainer = (StreamContainer)FindNode("StreamContainer");
        _streamContainerArea = _streamContainer.GetNode<Area>("Area");
        _streamContainerActiveTiles = _streamContainer.GetNode<Spatial>("ActiveTiles");

        _player = GetNode<Player>("Player");
        _tileWorld = GetNode<TileWorld>("TileWorld");
        _camera = (Camera)FindNode("Camera");
        _cameraOffset = _camera.GlobalTranslation - _player.GlobalTranslation;

        // populate UI values
        Slider generatorWorldSizeSlider = worldGeneratorContainer.GetNode<Slider>("HBoxContainer/WorldSizeSlider");
        generatorWorldSizeSlider.Value = _tileWorld.Size;

        Debug.Assert(_tileWorld != null);

        // resources        
        _tileHighlightScene = GD.Load<PackedScene>("utils/TileHighlight.tscn");
        _tileMaterial = GD.Load<ShaderMaterial>("materials/HexTileTextureLookup.tres");
        Debug.Assert(_tileMaterial != null);

        _blackWhitePatternTexture = new ImageTexture();
        Image image = new Image();
        image.Load("assets/4x4checker.png");
        _blackWhitePatternTexture.CreateFromImage(image, (uint)(Texture.FlagsEnum.Mipmaps | Texture.FlagsEnum.Repeat));

        // other members
        _lastTile = new HexCell();
        _currentTile = new HexCell();
        _hexGrid = new HexGrid();
        _interactionSystem = GetNode<InteractionSystem>("InteractionSystem");
        Debug.Assert(_interactionSystem != null);

        // update data
        _worldTextureRect.RectSize = Vector2.One * _tileWorld.Size;
        _heightTextureRect.RectSize = Vector2.One * _tileWorld.Size;

        // connect signals
        _streamContainerArea.Connect("input_event", this, nameof(OnAreaInputEvent));
        _streamContainer.Connect("TileClicked", this, nameof(OnTileClicked));
        _streamContainer.Connect("TileHovered", this, nameof(OnTileHovered));
        _tileWorld.Connect("WorldGenerated", this, nameof(OnWorldGenerated));
        _generateWorldButton.Connect("pressed", this, nameof(OnGenerateButton));
        _player.TaskQueueComponent.Connect("StartInteraction", _interactionSystem,
            nameof(_interactionSystem.OnStartInteraction));
        _player.Connect("GoldCountChanged", this, nameof(OnGoldCountChanged));

        // register entity events
        foreach (Node node in GetNode("Entities").GetChildren())
        {
            if (node.HasSignal("EntityClicked"))
            {
                node.Connect("EntityClicked", this, nameof(OnEntityClicked));
            }
        }

        // perform dependency injection
        //_streamContainer.SetWorld(_tileWorld);Clicked
        WorldInfoComponent worldInfoComponent = _player.GetNode<WorldInfoComponent>("WorldInfo");
        if (worldInfoComponent != null)
        {
            worldInfoComponent.SetWorld(_tileWorld);
        }

        _tileWorld.Generate(_tileWorld.Size);
        UpdateCurrentTile();
        _streamContainer.SetCenterTile(_currentTile);
    }

    public void CreateTileGrid()
    {
        foreach (int x_index in Enumerable.Range(-3, 6))
        {
            foreach (int y_index in Enumerable.Range(0, 1))
            {
                var tile = (Spatial)_tileHighlightScene.Instance();
                HexCell cell = new HexCell();
                Vector2 planeCoords = _hexGrid.GetHexCenterFromOffset(new Vector2(x_index, y_index));
                Transform tileTransform = Transform.Identity;
                tileTransform.origin.x = planeCoords.x;
                tileTransform.origin.z = planeCoords.y;
                tile.Transform = tileTransform;
                AddChild(tile);
                GD.Print("Added tile at offset coords " + new Vector2(x_index, y_index).ToString() +
                         " and world coords " + tileTransform.origin.ToString());
            }
        }
    }


    public void UpdateCurrentTile()
    {
        // cast a ray from the camera to center
        Vector3 cameraNormal = _camera.ProjectRayNormal(_camera.GetViewport().Size * 0.5f);
        Vector3 cameraPosition = _camera.ProjectRayOrigin(_camera.GetViewport().Size * 0.5f);
        Vector3 cameraDir = cameraNormal - cameraPosition;

        Vector3 centerCoord;

        if (Mathf.Abs(cameraDir.y) > Globals.EpsPosition)
        {
            centerCoord = cameraPosition + cameraNormal * (-cameraPosition.y / cameraNormal.y);
        }
        else
        {
            centerCoord = _camera.GlobalTranslation;
            centerCoord.y = 0;
        }


        _currentTile = _hexGrid.GetHexAt(new Vector2(centerCoord.x, centerCoord.z));

        _centerLabel.Text = centerCoord.ToString("F3");
        _tileOffsetLabel.Text = _currentTile.OffsetCoords.ToString();
    }


    public override void _Process(float delta)
    {
        _framesPerSecondLabel.Text = Engine.GetFramesPerSecond().ToString();
        _lastTile = _currentTile;

        UpdateCurrentTile();

        Transform tileHighlightTransform = Transform.Identity;
        Vector2 currentTileCenter = _hexGrid.GetHexCenter(_currentTile);
        tileHighlightTransform.origin.x = currentTileCenter.x;
        tileHighlightTransform.origin.z = currentTileCenter.y;
        _tileHighlight.Transform = tileHighlightTransform;

        if (_currentTile.CubeCoords != _lastTile.CubeCoords)
        {
            _streamContainer.SetCenterTile(_currentTile);

            _numTilesLabel.Text = _streamContainerActiveTiles.GetChildCount().ToString();
            _numCoordsAddedLabel.Text = _streamContainer.AddedCoords.Count.ToString();
            _numCoordsRemovedLabel.Text = _streamContainer.RemovedCoords.Count.ToString();
        }

        Transform cameraTransform = _camera.Transform;
        cameraTransform.origin = _player.GlobalTranslation + _cameraOffset;
        _camera.Transform = cameraTransform;
    }


    public void OnGenerateButton()
    {
        GD.Print("Generating");
        Slider worldSizeSlider = (Slider)FindNode("WorldSizeSlider");
        if (worldSizeSlider == null)
        {
            GD.PrintErr("Could not find WorldSizeSlider!");
            return;
        }

        _tileWorld.Seed = _tileWorld.Seed + 1;
        _tileWorld.Generate((int)worldSizeSlider.Value);
    }


    public void OnAreaInputEvent(Node camera, InputEvent inputEvent, Vector3 position, Vector3 normal,
        int shapeIndex)
    {
        HexCell cellAtCursor = _hexGrid.GetHexAt(new Vector2(position.x, position.z));
        Transform highlightTransform = Transform.Identity;

        _mouseWorldLabel.Text = position.ToString("F3");
        _mouseTileOffsetLabel.Text = cellAtCursor.OffsetCoords.ToString("N");
        _mouseTileCubeLabel.Text = cellAtCursor.CubeCoords.ToString("N");
        _mouseTileHighlight.Transform = highlightTransform;

        if (inputEvent is InputEventMouseButton && ((InputEventMouseButton)inputEvent).Pressed)
        {
            _streamContainer.EmitSignal("TileClicked", _streamContainer.GetTile3dAt(cellAtCursor.OffsetCoords));
        }
    }


    public void OnTileClicked(HexTile3D tile)
    {
        if (_player == null)
        {
            return;
        }

        if (_player.InteractionComponent != null)
        {
            _player.InteractionComponent.EmitSignal("InteractionEnd");
        }

        _player.TaskQueueComponent.Reset();
        _player.TaskQueueComponent.Queue.Enqueue(new TaskQueueComponent.NavigationTask(
            new NavigationComponent.NavigationPoint(tile.GlobalTranslation)));
    }

    public void OnTileHovered(HexTile3D tile)
    {
        Transform highlightTransform = tile.GlobalTransform;
        _mouseTileHighlight.Transform = highlightTransform;
        _mouseWorldLabel.Text = highlightTransform.origin.ToString("F3");
        _mouseTileOffsetLabel.Text = tile.OffsetCoords.ToString("N");
        _mouseTileCubeLabel.Text = tile.Cell.CubeCoords.ToString("N");

        _player.Navigation.FindPath(_player, _player.GlobalTranslation, tile.GlobalTranslation);
    }

    public void OnEntityClicked(Entity entity)
    {
        GD.Print("Clicked on entity at " + entity.GlobalTranslation);

        Spatial mountPoint = (Spatial)entity.FindNode("MountPoint");
        if (mountPoint != null)
        {
            _player.TaskQueueComponent.Reset();
            _player.TaskQueueComponent.Queue.Enqueue(new TaskQueueComponent.NavigationTask(
                new NavigationComponent.NavigationPoint(mountPoint.GlobalTransform)));
            _player.TaskQueueComponent.Queue.Enqueue(new TaskQueueComponent.InteractionTask(entity));
        }
    }


    public void ResetGameState()
    {
        Transform playerStartTransform = Transform.Identity;
        float height = _tileWorld.GetHeightAtOffset(new Vector2(0, 0));
        playerStartTransform.origin.y = height;
        _player.Transform = playerStartTransform;
        _player.TaskQueueComponent.Reset();
        _player.Navigation.PlanDirectPath(_player, playerStartTransform.origin, playerStartTransform.origin,
            playerStartTransform.basis.Quat());

        _goldCountLabel.Text = "0";

        foreach (Spatial entity in GetNode("Entities").GetChildren())
        {
            Transform entityTransform = entity.Transform;
            Vector2 entityPlanePos = new Vector2(entityTransform.origin.x, entityTransform.origin.z);
            Vector2 entityOffsetCoordinates = _hexGrid.GetHexAt(entityPlanePos).OffsetCoords;
            float entityHeight = _tileWorld.GetHeightAtOffset(entityOffsetCoordinates);
            entityTransform.origin.y = entityHeight;
            entity.Transform = entityTransform;
        }
    }

    public void OnWorldGenerated()
    {
        GD.Print("Using new map. Size: " + (int)_tileWorld.ColormapImage.GetSize().x);

        _goldCountLabel.Text = "0";

        UpdateWorldTextures();

        _streamContainer.OnWorldGenerated();

        // Reset player transform to offset 0,0 and at current height
        ResetGameState();

        // Connect all signals of the generated world
        foreach (Node node in _tileWorld.Entities.GetChildren())
        {
            if (node.HasSignal("EntityClicked"))
            {
                node.Connect("EntityClicked", this, nameof(OnEntityClicked));
            }
        }
    }

    private void UpdateWorldTextures()
    {
        GD.Print("Updating World textures");

        ImageTexture newWorldTexture = new ImageTexture();
        newWorldTexture.CreateFromImage(_tileWorld.ColormapImage,
            (uint)(Texture.FlagsEnum.Mipmaps | Texture.FlagsEnum.Repeat));
        _worldTextureRect.Texture = newWorldTexture;
        _tileMaterial.SetShaderParam("MapAlbedoTexture", newWorldTexture);
        _tileMaterial.SetShaderParam("TextureSize", (int)_tileWorld.ColormapImage.GetSize().x);

        ImageTexture newHeightTexture = new ImageTexture();
        newHeightTexture.CreateFromImage(_tileWorld.HeightmapImage,
            (uint)(Texture.FlagsEnum.Mipmaps | Texture.FlagsEnum.Repeat));
        _heightTextureRect.Texture = newHeightTexture;
    }

    public void OnGoldCountChanged(int goldCount)
    {
        AnimationPlayer animationPlayer = _gameUi.GetNode<AnimationPlayer>("AnimationPlayer");
        _goldCountLabel.Text = goldCount.ToString();
        animationPlayer.CurrentAnimation = "FlashLabel";
        animationPlayer.Seek(0);
        animationPlayer.Play();
    }
}