using Godot;

namespace RogueTank.Util;

public static class PixelArt
{
    public static Texture2D MakeSolidTexture(int w, int h, Color color)
    {
        var img = Image.Create(w, h, false, Image.Format.Rgba8);
        img.Fill(color);
        return ImageTexture.CreateFromImage(img);
    }

    public static Texture2D MakeTankTexture(int size, Color body, Color turret)
    {
        var img = Image.Create(size, size, false, Image.Format.Rgba8);
        img.Fill(Colors.Transparent);

        // Body
        var margin = Mathf.Max(1, size / 8);
        var bodyRect = new Rect2I(margin, margin * 2, size - margin * 2, size - margin * 3);
        FillRect(img, bodyRect, body);

        // Tracks
        FillRect(img, new Rect2I(margin / 2, margin * 2, margin, size - margin * 3), body.Darkened(0.25f));
        FillRect(img, new Rect2I(size - margin - margin / 2, margin * 2, margin, size - margin * 3), body.Darkened(0.25f));

        // Turret
        var t = Mathf.Max(2, size / 4);
        FillRect(img, new Rect2I(size / 2 - t / 2, size / 2 - t / 2, t, t), turret);
        // Barrel
        FillRect(img, new Rect2I(size / 2 - 1, margin, 2, size / 2 - margin), turret.Lightened(0.1f));

        return ImageTexture.CreateFromImage(img);
    }

    public static Texture2D MakeBulletTexture(int w, int h, Color color)
    {
        var img = Image.Create(w, h, false, Image.Format.Rgba8);
        img.Fill(Colors.Transparent);
        FillRect(img, new Rect2I(0, 0, w, h), color);
        return ImageTexture.CreateFromImage(img);
    }

    public static Texture2D MakePickupTexture(int size, Color color)
    {
        var img = Image.Create(size, size, false, Image.Format.Rgba8);
        img.Fill(Colors.Transparent);
        // simple diamond
        var c = size / 2;
        for (int y = 0; y < size; y++)
        {
            for (int x = 0; x < size; x++)
            {
                var dx = Mathf.Abs(x - c);
                var dy = Mathf.Abs(y - c);
                if (dx + dy <= c)
                    img.SetPixel(x, y, color);
            }
        }
        return ImageTexture.CreateFromImage(img);
    }

    private static void FillRect(Image img, Rect2I rect, Color c)
    {
        for (int y = rect.Position.Y; y < rect.Position.Y + rect.Size.Y; y++)
        {
            for (int x = rect.Position.X; x < rect.Position.X + rect.Size.X; x++)
                img.SetPixel(x, y, c);
        }
    }
}