using System;
using System.Collections.Generic;
using System.Diagnostics;
using Quik;
using Quik.VertexGenerator;
using OpenTK.Mathematics;
using OpenTK.Graphics.OpenGL4;
using OpenTK.Windowing.Common;
using OpenTK.Windowing.Desktop;
using OpenTK.Windowing.GraphicsLibraryFramework;
using Quik.FreeType;
using Quik.OpenTK;
using Quik.Typography;
using Quik.Controls;
using Quik.OpenGL;
using GL = Quik.OpenGL.GL;
using static Quik.OpenGL.GLEnum;
using Quik.CommandMachine;

namespace QuikTestApplication
{
    public class Program
    {
        public const string vertex =
            @"#version 140
uniform mat4 matrix;
in vec2 position;
in vec2 texcoord;
in vec4 color;
out vec2 ftexcoord;
out vec4 fcolor;

void main()
{
    fcolor = color;
    ftexcoord = texcoord;
    gl_Position = matrix * vec4(position.xy, 0, 1);
}
";

        public const string fragment =
            @"#version 140
in vec2 ftexcoord;
in vec4 fcolor;
out vec4 outcolor;

uniform sampler2D texture0;
uniform vec2 texture0offset;

void main()
{
    outcolor = fcolor * texture(texture0, ftexcoord + texture0offset);
}
";

        public static void Main(string[] args)
        {
            NativeWindowSettings windowSettings = NativeWindowSettings.Default;
            windowSettings.NumberOfSamples = 4;
            NativeWindow window = new NativeWindow(windowSettings);

            window.Context.MakeCurrent();
            GL.LoadBindings(new GLFWBindingsContext().GetProcAddress);

            FreeTypeFontManager fontManager = new FreeTypeFontManager();
            QuikContext           context = new QuikContext(new OpenGLTextureManager(), fontManager);

            VertexGeneratorEngine engine    = new VertexGeneratorEngine();
            CommandQueue          cmdQueue  = new CommandQueue();
            GL30Driver            gldriver;

            RootControl root = new RootControl(context);
            Button button = new Button()
            {
                Bounds = new QRectangle(120, 60, 20, 20),
                Text = "button",
                Padding = 8,
                NormalStroke = new QuikStrokeStyle(new QColor(0xccccccff), 4f),
                HoverStroke = new QuikStrokeStyle(new QColor(0x1010ccff), 4f),
                ActiveStroke = new QuikStrokeStyle(new QColor(0x999999ff), 4f),
            };
            button.Clicked += (sender, args) => {
                if (!args.Buttons.HasFlag(Quik.MouseButton.Primary))
                    return;

                Button xbutton = (Button)sender;

                if (xbutton.Text == "button")
                {
                    xbutton.Text = "le button";
                }
                else
                {
                    xbutton.Text = "button";
                }
            };
            root.MouseEnter += (_,_) => Console.WriteLine("enter");
            root.MouseLeave += (_,_) => Console.WriteLine("leave");
            root.MouseMove  += (_,_) => Console.WriteLine("move");
            root.MouseDown  += (_,_) => Console.WriteLine("down");
            root.MouseUp    += (_,_) => Console.WriteLine("up");
            root.Add(button);

            GL.Enable(GL_MULTISAMPLE);

            gldriver = new GL30Driver();

            window.Context.SwapInterval = 0;
            Stopwatch stopwatch = Stopwatch.StartNew();
            float lastMs = stopwatch.ElapsedMilliseconds;
            int frames = 0;
            for (;!window.IsExiting;)
            {
                NativeWindow.ProcessWindowEvents(false);
                window.ProcessEvents(0.0f);
                window.TryGetCurrentMonitorDpi(out float dpi, out _);

                if (window.IsFocused)
                {
                    var mouseState = window.MouseState;
                    QVec2 postion = new QVec2(mouseState.Position.X, window.ClientSize.Y - mouseState.Position.Y) * (dpi/72f);
                    Quik.MouseButton buttons =
                        (mouseState.IsButtonDown(OpenTK.Windowing.GraphicsLibraryFramework.MouseButton.Button1) ? Quik.MouseButton.Primary : 0) |
                        (mouseState.IsButtonDown(OpenTK.Windowing.GraphicsLibraryFramework.MouseButton.Button2) ? Quik.MouseButton.Secondary : 0) |
                        (mouseState.IsButtonDown(OpenTK.Windowing.GraphicsLibraryFramework.MouseButton.Button3) ? Quik.MouseButton.Tertiary : 0);

                    root.NotifyMouse(new Quik.MouseState(postion, buttons));
                }

                root.Bounds = new QRectangle(
                    window.ClientSize.X,
                    window.ClientSize.Y,
                    0,
                    0);
                root.NotifyUpdate();

                cmdQueue.Clear();
                root.NotifyPaint(cmdQueue);

                engine.Reset();
                engine.ProcessCommands(root.Bounds, cmdQueue);

                DrawQueue drawQueue = engine.DrawQueue;

                GL.Clear(GL_COLOR_BUFFER_BIT);
                gldriver.Draw(drawQueue);

                window.Context.SwapBuffers();

                frames++;
                float ms = stopwatch.ElapsedMilliseconds; 
                if (ms - lastMs > 1000)
                {
                    Console.WriteLine("Frames: {0}", frames*(ms - lastMs)/1000);
                    frames = 0;
                    lastMs = ms;
                    Console.WriteLine("Vertex Usage: {0} ; Element Usage: {1} Calls: {2}", drawQueue.VertexCount, drawQueue.ElementCount, drawQueue.DrawCallCount);
                }
            }
        }

        public class TextFontManager : IQuikFontManager
        {
            public QuikContext Context { get; set; }

            private TestFont _font;

            public void Clear()
            {
            }

            public QuikFont GetFont(QuikFontStyle fontStyle)
            {
                if (_font is null)
                {
                    _font = new TestFont(Context);
                }

                return _font;
            }
        }
    }
}