#include<windows.h>
#include<stdio.h>
#include"bmp_io.h"

LRESULT CALLBACK WndProc(HWND,UINT,WPARAM,LPARAM);
ATOM InitApp(HINSTANCE);
BOOL InitInstance(HINSTANCE,int);

void threshold(LPDWORD image_in,LPDWORD image_out,int thresh,int mode);
void histgram(LPDWORD image_in,long hist[256]);
void histsmooth(long hist_in[256],long hist_out[256]);

char szClassName[]="template";

int iWidth,iHeight;
const int HIGH=0x00ffffff,LOW=0x00000000;

int WINAPI WinMain(HINSTANCE hCurInst,HINSTANCE hPrevInst,
				   LPSTR lpsCmdLine,int nCmdShow)
{
	MSG msg;
	BOOL bRet;

	if(!InitApp(hCurInst))
		return FALSE;
	if(!InitInstance(hCurInst,nCmdShow))
		return FALSE;
	while((bRet=GetMessage(&msg,NULL,0,0))!=0){
		if(bRet==-1){
			MessageBox(NULL,"GetMessageエラー","Error",MB_OK);
			break;
		}else{
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	}
	return (int)msg.wParam;
}

ATOM InitApp(HINSTANCE hInst)
{
	WNDCLASSEX wc;
	wc.cbSize=sizeof(WNDCLASSEX);
	wc.style=CS_HREDRAW | CS_VREDRAW;
	wc.lpfnWndProc=WndProc;
	wc.cbClsExtra=0;
	wc.cbWndExtra=0;
	wc.hInstance=hInst;
	wc.hIcon=(HICON)LoadImage(NULL,
		MAKEINTRESOURCE(IDI_APPLICATION),
		IMAGE_ICON,
		0,0,
		LR_DEFAULTSIZE|LR_SHARED);
	wc.hCursor=(HCURSOR)LoadImage(NULL,
		MAKEINTRESOURCE(IDC_ARROW),
		IMAGE_CURSOR,
		0,0,
		LR_DEFAULTSIZE|LR_SHARED);
	wc.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);
	wc.lpszMenuName=NULL;
	wc.lpszClassName=(LPCTSTR)szClassName;
	wc.hIconSm=(HICON)LoadImage(NULL,
		MAKEINTRESOURCE(IDI_APPLICATION),
		IMAGE_ICON,
		0,0,
		LR_DEFAULTSIZE|LR_SHARED);

	return RegisterClassEx(&wc);
}

BOOL InitInstance(HINSTANCE hInst,int nCmdShow)
{
	HWND hWnd;

	hWnd=CreateWindow(szClassName,
		"第３章　物体を抜き出す",
		WS_OVERLAPPEDWINDOW,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		CW_USEDEFAULT,
		NULL,
		NULL,
		hInst,
		NULL);
	if(!hWnd)
		return FALSE;
	ShowWindow(hWnd,nCmdShow);
	UpdateWindow(hWnd);
	return TRUE;
}

LRESULT CALLBACK WndProc(HWND hWnd,UINT msg,WPARAM wp,LPARAM lp)
{
	static BMP_IO mybmp;
	
	static LPBITMAPINFO lpbiInfo;
	static LPDWORD lpPixel,lpPixel2;

	long hist[256];
	static long hist2[256];

	static int py=275;
	
	int i;
	HPEN hPen,hOldPen;
	RECT rc={300,0,800,250};
	char text[64];
	static char *info="8ビットBMPファイルをドロップして下さい\n\n"
	"<左上>原画像 or 処理結果\n<左下>ヒストグラム(平滑化しています)\n<右中>赤いラインの示すヒストグラム値\n\n"
	"↑↓：赤いラインが上下します\nEnter：(赤いラインがヒストグラム上にある場合)\n"
	"赤いラインの示す濃度値を閾値として2値化します\n(赤いラインがヒストグラム上にない場合)\n原画像に戻します";

	HDC hdc;
	PAINTSTRUCT ps;

	HDROP hDrop;
	char szFileName[256];

	switch(msg){
		case WM_CREATE:
			DragAcceptFiles(hWnd,TRUE);
			break;
		case WM_DROPFILES:
			hDrop=(HDROP)wp;
			DragQueryFile(hDrop,0,szFileName,sizeof(szFileName));
			DragFinish(hDrop);

			if(!mybmp.bmp_in(szFileName,hWnd)) break;

			lpbiInfo=&mybmp.biInfo;
			lpPixel=mybmp.lpPixel;

			iWidth=mybmp.iWidth;
			iHeight=mybmp.iHeight;

			lpPixel2=(LPDWORD)HeapAlloc(GetProcessHeap(),0,iWidth*iHeight*4);
			CopyMemory(lpPixel2,lpPixel,iWidth*iHeight*4);

			histgram(lpPixel,hist);
			histsmooth(hist,hist2);

			InvalidateRect(hWnd,NULL,TRUE);
			break;
		case WM_PAINT:
			hdc=BeginPaint(hWnd,&ps);
			for(i=0;i<256;i++){
				MoveToEx(hdc,0,300+i,NULL);
				LineTo(hdc,hist2[i]/2,300+i);
			}

			DrawText(hdc,info,-1,&rc,DT_WORDBREAK);
			if(py>=300 && py<300+256){
				sprintf(text,"濃度値%d: %d個(%lf%%)",
					py-300,hist2[py-300],(double)hist2[py-300]/(iWidth*iHeight)*100.0);
				TextOut(hdc,300,230,text,(int)strlen(text));
			}

			StretchDIBits(hdc,0,0,256,256,
				0,0,iWidth,iHeight,lpPixel2,lpbiInfo,
				DIB_RGB_COLORS,SRCCOPY);

			hPen=CreatePen(PS_SOLID,1,RGB(255,0,0));
			hOldPen=(HPEN)SelectObject(hdc,hPen);
			MoveToEx(hdc,0,py,NULL);
			LineTo(hdc,2048,py);
			SelectObject(hdc,hOldPen);
			DeleteObject(hPen);
			EndPaint(hWnd,&ps);
			break;
		case WM_KEYDOWN:
			switch(wp){
				case VK_UP:
					py--;
					break;
				case VK_DOWN:
					py++;
					break;
				case VK_RETURN:
					if(py>=300 && py<300+256)
						threshold(lpPixel,lpPixel2,py-300,2);
					else
						CopyMemory(lpPixel2,lpPixel,iWidth*iHeight*4);
					break;
			}
			InvalidateRect(hWnd,NULL,TRUE);
			break;
		case WM_CLOSE:
			HeapFree(GetProcessHeap(),0,lpPixel2);
			DestroyWindow(hWnd);
			break;
		case WM_DESTROY:
			PostQuitMessage(0);
			break;
		default:
			return DefWindowProc(hWnd,msg,wp,lp);
	}
	return 0;
}

void threshold(LPDWORD image_in,LPDWORD image_out,int thresh,int mode)
{
	int x,y,n;

	for(y=0;y<iHeight;y++)
		for(x=0;x<iWidth;x++){
			n=image_in[x+y*iWidth] & 0x000000ff;
			switch(mode){
				case 2:
					if(n<=thresh) image_out[x+y*iWidth]=HIGH;
					else image_out[x+y*iWidth]=LOW;
				default:
					if(n>=thresh) image_out[x+y*iWidth]=HIGH;
					else image_out[x+y*iWidth]=LOW;
			}
		}
}

void histgram(LPDWORD image_in,long hist[256])
{
	int x,y,n;

	for(n=0;n<256;n++)
		hist[n]=0;
	
	for(y=0;y<iHeight;y++)
		for(x=0;x<iWidth;x++){
			n=image_in[x+y*iWidth] & 0x000000ff;
			hist[n]++;
		}
}

void histsmooth(long hist_in[256],long hist_out[256])
{
	int m,n,i;
	long sum;

	for(n=0;n<256;n++){
		sum=0;
		for(m=-2;m<=2;m++){
			i=n+m;
			if(i<0) i=0;
			else if(i>255) i=255;
			sum+=hist_in[i];
		}
		hist_out[n]=(long)(sum/5.0+0.5);
	}
}