#include<windows.h>
#include"Lagrange.h"

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

char szClassName[]="Lagrange";

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,
		"ラグランジュの補間法",
		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)
{
	HDC hdc;
	PAINTSTRUCT ps;
	static lagrange lag;
	static int x[MAX],f[MAX],n,width,high;
	int i;
	static BOOL paint;
	char *lbutton="左クリック：座標追加";
	char *rbutton="右クリック：(再)描画";
	char *space="スペースキー：クリア";
	char *setsumei="適当なところを左クリックして下さい。右クリックする度に書き直されます。";
	char nokori[64];

	switch(msg){
		case WM_PAINT:
			hdc=BeginPaint(hWnd,&ps);
			SetTextColor(hdc,RGB(246,173,205));
			wsprintf(nokori,"あと最大 %d 個の座標を追加できます。",MAX-n);
			TextOut(hdc,0,0,nokori,(int)strlen(nokori));
			TextOut(hdc,0,high-80,lbutton,(int)strlen(lbutton));
			TextOut(hdc,0,high-60,rbutton,(int)strlen(rbutton));
			TextOut(hdc,0,high-40,space,(int)strlen(space));
			TextOut(hdc,0,high-20,setsumei,(int)strlen(setsumei));
			for(i=0;i<n;i++)
                Ellipse(hdc,x[i]-5,f[i]-5,x[i]+5,f[i]+5);
			if(paint)
				for(i=0;i<width;i++)
					if(i==0)
                        MoveToEx(hdc,i,(int)lag.hokan(i),NULL);
					else
                        LineTo(hdc,i,(int)lag.hokan(i));
			EndPaint(hWnd,&ps);
			break;
		case WM_LBUTTONDOWN:
			if(n<MAX){
				x[n]=LOWORD(lp);
				f[n]=HIWORD(lp);
				n++;
				InvalidateRect(hWnd,NULL,TRUE);
			}
			break;
		case WM_RBUTTONDOWN:
			lag.set(x,f,n);
			paint=TRUE;
			InvalidateRect(hWnd,NULL,TRUE);
			break;
		case WM_KEYDOWN:
			if(wp==VK_SPACE){
				n=0;
				paint=FALSE;
				InvalidateRect(hWnd,NULL,TRUE);
			}
			break;
		case WM_SIZE:
			width=LOWORD(lp);
			high=HIWORD(lp);
			break;
		case WM_CLOSE:
			DestroyWindow(hWnd);
			break;
		case WM_DESTROY:
			PostQuitMessage(0);
			break;
		default:
			return DefWindowProc(hWnd,msg,wp,lp);
	}
	return 0;
}