using System.Diagnostics;
using System.Linq;
using Godot;

public class WorldChunk : Spatial
{
    private Sprite _heightmapSprite;
    private TextureRect _heightmapTextureRect;
    private Sprite _noiseMask;

    private Sprite _noiseSprite;

    private readonly SpatialMaterial _rectMaterial = new();
    private bool _showTextureOverlay;
    [Export] public Vector2 ChunkIndex;
    public Color DebugColor = Colors.White;
    [Export] public Texture HeightMap;
    public int HeightMapFrameCount;

    public Viewport HeightmapOffscreenViewport;
    [Export] public Texture NavigationMap;

    public bool NoiseTextureCheckerboardOverlay = true;

    // signals
    // delegate void OnCoordClicked(Vector2 world_pos);

    // other members
    public Rect2 PlaneRect;
    // ui elements

    // scene nodes
    private MeshInstance PlaneRectMesh;
    [Export] public int Size = 32;

    // resources

    // exports
    [Export] public Texture TileTypeMap;
    public int TileTypeMapFrameCount;
    public Viewport TileTypeOffscreenViewport;

    public WorldChunk()
    {
    }

    public WorldChunk(int size)
    {
        SetSize(size);
    }

    [Export]
    public bool ShowTextureOverlay
    {
        get => _showTextureOverlay;

        set
        {
            if (PlaneRectMesh != null) PlaneRectMesh.Visible = value;
        }
    }

    // Called when the node enters the scene tree for the first time.
    public override void _Ready()
    {
        PlaneRectMesh = (MeshInstance)FindNode("PlaneRectMesh");
        Debug.Assert(PlaneRectMesh != null);
        if (PlaneRectMesh.Visible) _showTextureOverlay = true;

        var planeRectTransform = Transform.Identity;
        planeRectTransform =
            planeRectTransform.Scaled(new Vector3(PlaneRect.Size.x, 0.125f, PlaneRect.Size.y));
        planeRectTransform.origin.x = PlaneRect.GetCenter().x;

        planeRectTransform.origin.z = PlaneRect.GetCenter().y;

        PlaneRectMesh.Transform = planeRectTransform;

//        PlaneRectMesh.MaterialOverride = new SpatialMaterial();
//        ((SpatialMaterial)PlaneRectMesh.MaterialOverride).AlbedoColor = DebugColor;
//        ((SpatialMaterial)PlaneRectMesh.MaterialOverride).FlagsTransparent = true;

        HeightmapOffscreenViewport = (Viewport)FindNode("HeightmapOffscreenViewport");
        HeightmapOffscreenViewport.Size = Vector2.One * Size;
        Debug.Assert(HeightmapOffscreenViewport != null);
        _noiseSprite = (Sprite)FindNode("NoiseSprite");
        _noiseMask = (Sprite)FindNode("NoiseMask");
        _heightmapSprite = (Sprite)FindNode("HeightmapSprite");

        TileTypeOffscreenViewport = (Viewport)FindNode("TileTypeOffscreenViewport");
        TileTypeOffscreenViewport.Size = Vector2.One * Size;
        Debug.Assert(TileTypeOffscreenViewport != null);

        SetSize(World.ChunkSize);
    }

    public void SetSize(int size)
    {
        Size = size;

        if (TileTypeOffscreenViewport != null)
        {
            TileTypeOffscreenViewport.Size = Vector2.One * size;
            HeightmapOffscreenViewport.Size = Vector2.One * size;
            _noiseMask.Transform = Transform2D.Identity.Scaled(Vector2.One * size / _noiseMask.Texture.GetSize().x);
            _noiseSprite.Transform = Transform2D.Identity.Scaled(Vector2.One * size / _noiseSprite.Texture.GetSize().x);
            _heightmapSprite.Transform =
                Transform2D.Identity.Scaled(Vector2.One * size / _heightmapSprite.Texture.GetSize().x);
        }
    }

    // other members
    public void SaveToFile(string chunkName)
    {
        var image = new Image();

        image.CreateFromData(Size, Size, false, Image.Format.Rgba8, TileTypeMap.GetData().GetData());
        image.SavePng(chunkName + "_tileType.png");

        image.CreateFromData(Size, Size, false, Image.Format.Rgba8, NavigationMap.GetData().GetData());
        image.SavePng(chunkName + "_navigationMap.png");

        image.CreateFromData(Size, Size, false, Image.Format.Rgba8, HeightMap.GetData().GetData());
        image.SavePng(chunkName + "_heightMap.png");
    }

    public void LoadFromFile(string chunkName)
    {
    }


    public void SetNoisemap(Texture texture)
    {
        _noiseSprite.Texture = texture;
        _noiseSprite.Transform =
            Transform2D.Identity.Scaled(HeightmapOffscreenViewport.Size / _noiseSprite.Texture.GetSize().x);
        HeightmapOffscreenViewport.RenderTargetUpdateMode = Viewport.UpdateMode.Once;
        HeightMapFrameCount = 1;
    }

    public void SetHeightmap(Texture texture)
    {
        _heightmapSprite.Texture = texture;
        _heightmapSprite.Transform =
            Transform2D.Identity.Scaled(TileTypeOffscreenViewport.Size / _heightmapSprite.Texture.GetSize());

        TileTypeOffscreenViewport.RenderTargetUpdateMode = Viewport.UpdateMode.Once;
        TileTypeMapFrameCount = 1;
    }

    public override void _Process(float delta)
    {
        Texture tileTypeTexture = TileTypeOffscreenViewport.GetTexture();

        if (NoiseTextureCheckerboardOverlay)
        {
            var tileTypeImage = tileTypeTexture.GetData();
            tileTypeImage.Lock();

            foreach (var i in Enumerable.Range(0, Size))
            foreach (var j in Enumerable.Range(0, Size))
            {
                var textureCoord = new Vector2(i, j);
                var baseColor = tileTypeImage.GetPixelv(textureCoord);

                if ((i + j) % 2 == 0)
                    tileTypeImage.SetPixelv(textureCoord, baseColor);
                else
                    tileTypeImage.SetPixelv(textureCoord, baseColor * 0.6f);
            }

            tileTypeImage.Unlock();
            var imageTexture = new ImageTexture();
            imageTexture.CreateFromImage(tileTypeImage, 0);
            tileTypeTexture = imageTexture;
        }

        _rectMaterial.AlbedoTexture = tileTypeTexture;

        _rectMaterial.FlagsTransparent = true;
//        _rectMaterial.AlbedoTexture = _heightmapRect.Texture;
        _rectMaterial.Uv1Scale = new Vector3(-3, -2, 1);
        _rectMaterial.Uv1Offset = Vector3.One * 2;

        //RectMaterial.Uv1Triplanar = true;
        PlaneRectMesh.SetSurfaceMaterial(0, _rectMaterial);

        if (HeightMapFrameCount == 0) HeightmapOffscreenViewport.RenderTargetUpdateMode = Viewport.UpdateMode.Disabled;

        HeightMapFrameCount = HeightMapFrameCount > 0 ? HeightMapFrameCount - 1 : 0;

        if (TileTypeMapFrameCount == 0) TileTypeOffscreenViewport.RenderTargetUpdateMode = Viewport.UpdateMode.Disabled;

        TileTypeMapFrameCount = TileTypeMapFrameCount > 0 ? TileTypeMapFrameCount - 1 : 0;

        PlaneRectMesh.MaterialOverride = null;
    }
}