// Copyright (c) 2021 ezequias2d <ezequiasmoises@gmail.com> and the Peridot contributors
// This code is licensed under MIT license (see LICENSE for details)
using System.Drawing;
using Veldrid;
using Veldrid.StartupUtilities;
using System.Numerics;
using Peridot.Demo;

using StbImageSharp;
using System.Diagnostics;
using Rectangle = System.Drawing.Rectangle;
using Peridot;
using Peridot.Text;

var title = "Peridot.Demo";
var wci = new WindowCreateInfo(100, 100, 640, 480, WindowState.Normal, title);

var window = VeldridStartup.CreateWindow(wci);
var gd = VeldridStartup.CreateVulkanGraphicsDevice(
	new(true,
		Veldrid.PixelFormat.D32_Float_S8_UInt,
		true,
		ResourceBindingModel.Default,
		true,
		true),
	window);

window.Resized += () =>
{
	gd.MainSwapchain.Resize((uint)window.Width, (uint)window.Height);
};

var peridot = new VPeridot(gd);

var shaders = peridot.LoadDefaultShaders();
var sbd = new SpriteBatchDescriptor(gd.MainSwapchain.Framebuffer.OutputDescription, shaders);
var sb = peridot.CreateSpriteBatch(sbd);

var tr = new TextRenderer(peridot, sb);
var cl = gd.ResourceFactory.CreateCommandList();
var fence = gd.ResourceFactory.CreateFence(false);
var texture = LoadTexture(Resource._4_2_07);
var font = LoadFont(Resource.romulus);
var count = 0;

var time = DateTime.Now;
var neg = false;
var ps = 0;
while (window.Exists)
{
	count++;

	var now = DateTime.Now;
	var delta = now - time;
	var deltaTime = delta.TotalSeconds;
	time = now;

	if((count % 1000) == 0)
	{
		window.Title = title + " " + (1f / deltaTime);
	}

	window.PumpEvents();

	sb.Begin();
	sb.ViewMatrix = Matrix4x4.CreateOrthographic(window.Width, window.Height, 0.01f, -100f);
	
	var size = new Vector2(texture.Width, texture.Height);
	var pos = size * -0.5f;
	var source = new System.Drawing.Rectangle((int)texture.Width / 2, (int)texture.Height / 2, (int)texture.Width / 2, (int)texture.Height / 2);

	ps += neg ? -1 : 1;
	if (ps == 0 || ps == 100)
		neg = !neg;

	var options = ps >= 0 && ps < 25 ? SpriteOptions.None :
				  ps >= 25 && ps < 50 ? SpriteOptions.FlipVertically :
				  ps >= 50 && ps < 75 ? SpriteOptions.FlipVertically | SpriteOptions.FlipHorizontally :
										SpriteOptions.FlipHorizontally;

	sb.Draw(texture, default, source, Color.White, 0, new(-size.X / 6, 0), Vector2.One, options, 1f);

	var s = font.MeasureString("Hello World!", 32);
	var strScissor = new Rectangle(0, 0, (int)s.X, (int)s.Y * ps / 100);
	tr.DrawString(font, 32, "Hello World!", new Vector2(1, 1), Color.White, 0, new Vector2(0, 0), new Vector2(1), 2f, strScissor);
	sb.End();

	cl.Begin();
	cl.SetFramebuffer(gd.SwapchainFramebuffer);
	cl.ClearColorTarget(0, RgbaFloat.CornflowerBlue);
	cl.ClearDepthStencil(0f);
	cl.DrawBatch(sb);
	cl.End();

	fence.Reset();
	gd.SubmitCommands(cl, fence);
	gd.WaitForFence(fence);
	gd.SwapBuffers();
}

Texture LoadTexture(byte[] data)
{
	ImageResult image;
	{
		image = ImageResult.FromMemory(data, ColorComponents.Default);
		Debug.Assert(image != null);
	}

	var td = new TextureDescription(
		(uint)image.Width, (uint)image.Height, 1,
		1, 1,
		Veldrid.PixelFormat.R8_G8_B8_A8_UNorm,
		TextureUsage.Sampled,
		TextureType.Texture2D);

	var texture = gd.ResourceFactory.CreateTexture(td);
	gd.UpdateTexture(texture, image.Data, 0, 0, 0, td.Width, td.Height, td.Depth, 0, 0);

	return texture;
}

Font LoadFont(byte[] data)
{
	using var stream = new MemoryStream();
	stream.Write(data);
	stream.Position = 0;
	var font = new Font();
	font.AddFont(data);
	return font;
}