// include the basic windows header files and the Direct3D header file
#include <d3d9.h>
#include <d3dx9.h>
#include <windows.h>
#include <windowsx.h>
#include "Camera.h"

#pragma comment (lib, "d3d9.lib")
#pragma comment (lib, "d3dx9.lib")
#pragma comment (lib, "Dinput8.lib")
#pragma comment (lib, "dxguid.lib")
#pragma comment (lib, "winmm.lib")
#pragma comment (lib, "strmiids.lib")

// define the screen resolution and keyboard macros
#define SCREEN_WIDTH 1280
#define SCREEN_HEIGHT 720
#define KEY_DOWN(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)
#define KEY_UP(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 0 : 1)

// global declarations
LPDIRECT3D9 d3d;    // the pointer to our Direct3D interface
LPDIRECT3DDEVICE9 d3ddev;    // the pointer to the device class
LPDIRECT3DSURFACE9 z_buffer = NULL;    // the pointer to the z-buffer

ID3DXMesh*              g_pMesh = NULL;
IDirect3DTexture9*      g_pMeshTexture = NULL;  // Mesh texture
D3DXMATRIXA16           g_mCenterWorld;
ID3DXEffect*            g_pEffect = NULL;
float temp;
// function prototypes
void initD3D(HWND hWnd,HINSTANCE hInstance);    // sets up and initializes Direct3D
void render_frame(void);    // renders a single frame
void cleanD3D(void);    // closes Direct3D and releases memory
void init_light(void);

LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);


// the entry point for any Windows program
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,LPSTR lpCmdLine, int nCmdShow){
    HWND hWnd;
    WNDCLASSEX wc;

    ZeroMemory(&wc, sizeof(WNDCLASSEX));

    wc.cbSize = sizeof(WNDCLASSEX);
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = (WNDPROC)WindowProc;
    wc.hInstance = hInstance;
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.lpszClassName = "PirateShipWars";

    RegisterClassEx(&wc);

    hWnd = CreateWindowEx(NULL,
                          "PirateShipWars",
                          "Our Direct3D Program",
                          WS_OVERLAPPEDWINDOW,
                          0, 0,
                          SCREEN_WIDTH, SCREEN_HEIGHT,
                          NULL,
                          NULL,
                          hInstance,
                          NULL);

    ShowWindow(hWnd, nCmdShow);

    // set up and initialize Direct3D
    initD3D(hWnd,hInstance);
    // enter the main loop:

    MSG msg;

    while(TRUE)
    {
        DWORD starting_point = GetTickCount();

        if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
        {
            if (msg.message == WM_QUIT)
                break;

            TranslateMessage(&msg);
            DispatchMessage(&msg);
        }

        render_frame();

        if(KEY_DOWN(VK_ESCAPE))
        {
             PostMessage(hWnd, WM_DESTROY, 0, 0);
        }


        while ((GetTickCount() - starting_point) < 25);
    }

    // clean up DirectX and COM
    cleanD3D();

    return msg.wParam;
}


// this is the main message handler for the program
LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch(message)
    {
        case WM_DESTROY:
            {
                PostQuitMessage(0);
                return 0;
            } break;
    }

    return DefWindowProc (hWnd, message, wParam, lParam);
}


// this function initializes and prepares Direct3D for use
void initD3D(HWND hWnd, HINSTANCE hInstance)
{
    d3d = Direct3DCreate9(D3D_SDK_VERSION);
    D3DPRESENT_PARAMETERS d3dpp;


    ZeroMemory(&d3dpp, sizeof(d3dpp));
    d3dpp.Windowed = true;
    d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
    d3dpp.hDeviceWindow = hWnd;
    d3dpp.BackBufferFormat = D3DFMT_X8R8G8B8;
    d3dpp.BackBufferWidth = SCREEN_WIDTH;
    d3dpp.BackBufferHeight = SCREEN_HEIGHT;
    d3dpp.EnableAutoDepthStencil = TRUE;
    d3dpp.AutoDepthStencilFormat = D3DFMT_D16;

    // create a device class using this information and the info from the d3dpp stuct
    d3d->CreateDevice(D3DADAPTER_DEFAULT,
                      D3DDEVTYPE_HAL,
                      hWnd,
                      D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                      &d3dpp,
                      &d3ddev);


    // create the z-buffer
    d3ddev->CreateDepthStencilSurface(SCREEN_WIDTH,
                                      SCREEN_HEIGHT,
                                      D3DFMT_D16,
                                      D3DMULTISAMPLE_NONE,
                                      0,
                                      TRUE,
                                      &z_buffer,
                                      NULL);

    // using the shader debugger.
    DWORD dwShaderFlags = D3DXFX_NOT_CLONEABLE;

    D3DXLoadMeshFromX("box.x", D3DXMESH_MANAGED, d3ddev, NULL, NULL, NULL, NULL, &g_pMesh);

    //Test compilation buffer variable
    LPD3DXBUFFER d3dBuffer;

    // If this fails, there should be debug output as to
    // why the .fx file failed to compile
    D3DXCreateEffectFromFile( d3ddev, "Ambient.fx", NULL, NULL, dwShaderFlags, NULL, &g_pEffect, &d3dBuffer ); //dwShaderFlags (5)

    float temp = 0;
    D3DXVECTOR4 Acolour = D3DXVECTOR4(1,0,1,1);

    g_pEffect->SetVector( "AmbientColor" , &Acolour);

    float Dtemp = 0.8f;
    D3DXVECTOR4 DColour = D3DXVECTOR4( 0, 1, 0, 1 );
    D3DXVECTOR4 DLight = D3DXVECTOR4( .7f, 1.0f, -.8f, 0 );
    g_pEffect->SetFloat( "DiffuseIntensity", Dtemp);
    g_pEffect->SetVector( "DiffuseColor" , &DColour);
    g_pEffect->SetVector( "DiffuseLightDirection" , &DLight);

    D3DXVECTOR3 eye(0, 10, 10);
    D3DXVECTOR3 at(0, 0, 0);
    D3DXVECTOR3 up(0, 1, 0);

    // Setup the matrices within the shader (shaders handle matrices on their own unlike the
    // fixed function pipeline)
    D3DXMATRIX worldMatrix;
    D3DXMatrixTranslation(&worldMatrix, 0,0, 0);

    D3DXMATRIX viewMatrix;
    D3DXMatrixLookAtLH(&viewMatrix, &eye, &at, &up);

    D3DXMATRIX projectionMatrix;
    D3DXMatrixPerspectiveFovLH(&projectionMatrix,
            D3DXToRadian(45),    // the horizontal field of view
            (FLOAT)1920  / (FLOAT)1080, // aspect ratio
            1.0f,   // the near view-plane
            70000.0f);    // the far view-plane

    g_pEffect->SetMatrix( "World", &worldMatrix);
    g_pEffect->SetMatrix( "View", &viewMatrix );
    g_pEffect->SetMatrix( "Projection", &projectionMatrix );


    return;
}


// this is the function used to render a single frame
void render_frame(void)
{
    if(temp < 1)
    {
        temp += 0.02;
    }
    else
    {
        temp = 0;
    }
    g_pEffect->SetFloat( "AmbientIntensity", temp);

    UINT iPass, cPasses;

    // Clear the render target and the zbuffer
    d3ddev->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, D3DXCOLOR(0.0f,0.0,0.0,0.0), 1.0f, 0);


    d3ddev->BeginScene();
    // Apply the technique contained in the effect
    g_pEffect->Begin(&cPasses, 0);

    for (iPass = 0; iPass < cPasses; iPass++)
    {
        g_pEffect->BeginPass(iPass);

        g_pMesh->DrawSubset(0);

        g_pEffect->EndPass();
    }
    g_pEffect->End();

    d3ddev->EndScene();
    d3ddev->Present(NULL, NULL, NULL, NULL);

    return;
}


// this is the function that cleans up Direct3D and COM
void cleanD3D(void)
{
    d3ddev->Release();    // close and release the 3D device
    d3d->Release();    // close and release Direct3D
    return;
}