//-----------------------------------------------------------------------
// -----------------------------------------------------------------------
// file="ViewBase"
// Project: StgSharp
// AuthorGroup: Nitload
// Copyright (c) Nitload. All rights reserved.
//     
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//     
// -----------------------------------------------------------------------
// -----------------------------------------------------------------------
using StgSharp.Graphics;
using StgSharp.Mathematics;
using StgSharp.MVVM.ViewModel;
using StgSharp.Timing;

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Linq;
using System.Numerics;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Security.Cryptography;
using System.Text;
using System.Threading;

namespace StgSharp.MVVM
{
    /// <summary>
    ///   ViewBase is the base type for all view types, providing context binding and control
    ///   element binding. A complete view should contain one complete <see cref="ViewDesigner{T}"
    ///   />, <see cref="ViewRender{TView}" />, and <see cref="ViewResponder" />, which provide
    ///   layout descriptions of control elements, user responses, and rendering implementations in
    ///   the view. Data between instances of <see cref="ViewDesigner{T}" />, <see
    ///   cref="ViewRender{TView}" />, and <see cref="ViewResponder{T}" /> is shared through <see
    ///   cref="ViewBase" />.
    /// </summary>

    public abstract unsafe partial class ViewBase
    {

        private (int x, int y, int z) unitCubeSize;

        private GetDataBindingEntryDelegate getDataBindingEntry;

        private int usedFrame;
        private IViewDesigner<ViewBase> _design;
        private IViewRender<ViewBase> _render;
        private IViewResponder<ViewBase> _responder;
        private TimeSpanProvider time;

        private ViewPort context;

        private delegate bool GetDataBindingEntryDelegate(string name, out DataBindingEntry entry);

        public DataBindingEntry this[string name]
        {
            get
            {
                if (getDataBindingEntry(name, out DataBindingEntry entry)) {
                    return entry;
                }
                if (TryGetObjectReference(name, out entry)) {
                    return entry;
                }
                throw new KeyNotFoundException();
            }
        }

        public (int x, int y, int z) UnitCubeSize
        {
            get => unitCubeSize;
        }

        public bool Activated { get; internal set; }

        public int Height
        {
            get => context.Height;
        }

        public int Width
        {
            get => context.Width;
        }

        public IntPtr Monitor => context.Monitor;

        public IntPtr ViewHandle => context.ViewPortHandle;

        public IViewDesigner<ViewBase> Designer
        {
            get => _design;
            protected set => _design = value;
        }

        public string ContextName => context.Name;

        public string SelfName { get; set; }

        public ViewPort Port
        {
            get => context;
        }

        internal TimeSpanProvider TimeProvider
        {
            get => time;
        }

        protected internal IViewRender<ViewBase> Render
        {
            get => _render;
            set => _render = value;
        }

        protected IViewResponder<ViewBase> Responder
        {
            get => _responder;
            set => _responder = value;
        }

        public abstract void CustomizedInitialize([NotNull]ViewModelBase viewModelBinding);

        /// <summary>
        ///   Get the status of a certain key on the keyboard.
        /// </summary>
        /// <param _label="key">
        ///
        /// </param>
        /// <returns>
        ///   <see cref="KeyStatus" /> representing if a key is pressed or released.
        /// </returns>
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public KeyStatus GetKeyStatus(KeyboardKey key)
        {
            return GraphicFramework.glfwGetKey(context.ViewPortHandle, (int)key);
        }

        public void InternalInitialize(string name, (int, int, int) cubeSize, [NotNull]ViewModelBase viewModelBinding)
        {
            SelfName = name;
            unitCubeSize = cubeSize;
            getDataBindingEntry = viewModelBinding.TryGetObjectReference;
            context = viewModelBinding.ViewPortBinding;
            time = viewModelBinding.frameTimeProvider;

            CustomizedInitialize(viewModelBinding);
        }

        public abstract bool TryGetObjectReference(string name, out DataBindingEntry entry);

        public void Use()
        {
            if (usedFrame == 0)
            {
                if (!ValidateInitialization()) {
                    throw new InvalidOperationException(
                        "This view is not correctly initialized before rendering.");
                }
            }
            Show();
            usedFrame++;
        }

        public bool ValidateInitialization()
        {
            return (_design != null) &&
                   (_render != null) &&
                   (getDataBindingEntry != null) &&
                   (_responder != null) &&
                   _design.ValidateInitializing() &&
                   _responder.ValidateInitializing() &&
                   _render.ValidateInitializing();
        }

        protected abstract void Show();

    }
}