/*     Copyright 2019 Diligent Graphics LLC
 *  
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 *  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 OF ANY PROPRIETARY RIGHTS.
 *
 *  In no event and under no legal theory, whether in tort (including negligence), 
 *  contract, or otherwise, unless required by applicable law (such as deliberate 
 *  and grossly negligent acts) or agreed to in writing, shall any Contributor be
 *  liable for any damages, including any direct, indirect, special, incidental, 
 *  or consequential damages of any character arising as a result of this License or 
 *  out of the use or inability to use the software (including but not limited to damages 
 *  for loss of goodwill, work stoppage, computer failure or malfunction, or any and 
 *  all other commercial damages or losses), even if such Contributor has been advised 
 *  of the possibility of such damages.
 */

#ifndef NOMINMAX
#   define NOMINMAX
#endif
#include <wrl.h>
#include <wrl/client.h>

#include "imgui.h"
#include "ImGuiImplUWP.h"


namespace Diligent
{

ImGuiImplUWP::ImGuiImplUWP(IRenderDevice*  pDevice,
                           TEXTURE_FORMAT  BackBufferFmt,
                           TEXTURE_FORMAT  DepthBufferFmt,
                           Uint32          DisplayWidth,
                           Uint32          DisplayHeight,
                           Uint32          InitialVertexBufferSize,
                           Uint32          InitialIndexBufferSize) :
    ImGuiImplDiligent(pDevice, BackBufferFmt, DepthBufferFmt, InitialVertexBufferSize, InitialIndexBufferSize),
    m_DisplayWidth  (DisplayWidth),
    m_DisplayHeight (DisplayHeight)
{
    ::QueryPerformanceFrequency((LARGE_INTEGER *)&m_TicksPerSecond);
    ::QueryPerformanceCounter((LARGE_INTEGER *)&m_Time);

    // Setup back-end capabilities flags
    ImGuiIO& io = ImGui::GetIO();
    io.BackendPlatformName = "imgui_impl_uwp";

    // Keyboard mapping. ImGui will use those indices to peek into the io.KeysDown[] array that we will update during the application lifetime.
    io.KeyMap[ImGuiKey_Tab] = VK_TAB;
    io.KeyMap[ImGuiKey_LeftArrow] = VK_LEFT;
    io.KeyMap[ImGuiKey_RightArrow] = VK_RIGHT;
    io.KeyMap[ImGuiKey_UpArrow]    = VK_UP;
    io.KeyMap[ImGuiKey_DownArrow] = VK_DOWN;
    io.KeyMap[ImGuiKey_PageUp] = VK_PRIOR;
    io.KeyMap[ImGuiKey_PageDown] = VK_NEXT;
    io.KeyMap[ImGuiKey_Home] = VK_HOME;
    io.KeyMap[ImGuiKey_End] = VK_END;
    io.KeyMap[ImGuiKey_Insert] = VK_INSERT;
    io.KeyMap[ImGuiKey_Delete] = VK_DELETE;
    io.KeyMap[ImGuiKey_Backspace] = VK_BACK;
    io.KeyMap[ImGuiKey_Space] = VK_SPACE;
    io.KeyMap[ImGuiKey_Enter] = VK_RETURN;
    io.KeyMap[ImGuiKey_Escape] = VK_ESCAPE;
    io.KeyMap[ImGuiKey_KeyPadEnter] = VK_RETURN;
    io.KeyMap[ImGuiKey_A] = 'A';
    io.KeyMap[ImGuiKey_C] = 'C';
    io.KeyMap[ImGuiKey_V] = 'V';
    io.KeyMap[ImGuiKey_X] = 'X';
    io.KeyMap[ImGuiKey_Y] = 'Y';
    io.KeyMap[ImGuiKey_Z] = 'Z';
}

ImGuiImplUWP::~ImGuiImplUWP()
{
}

void ImGuiImplUWP::NewFrame()
{
    ImGuiIO& io = ImGui::GetIO();
    IM_ASSERT(io.Fonts->IsBuilt() && "Font atlas not built! It is generally built by the renderer back-end. Missing call to renderer _NewFrame() function? e.g. ImGui_ImplOpenGL3_NewFrame().");

    io.DisplaySize = ImVec2((float)m_DisplayWidth, (float)m_DisplayHeight);

    // Setup time step
    INT64 current_time;
    ::QueryPerformanceCounter((LARGE_INTEGER *)&current_time);
    io.DeltaTime = (float)(current_time - m_Time) / m_TicksPerSecond;
    m_Time = current_time;

    io.KeySuper = false;

    ImGuiImplDiligent::NewFrame();
}

}
