/*
 *  Window layer
 *
 *
 *  COPYRIGHT (c) 2001 - 2010.
 *  emTech System Corporation.
 *
 *  The license and distribution terms for this file may be
 *  found in found in the file LICENSE.
 */

/*	Huangf emcore@263.net
 */
 
#include "emGUI.h"

#include <stdlib.h>
#include <string.h>

void WndInitialization()
{
}

static void _SaveDrawArea(
	Window *win
)
{
	void *memory 	= win->memory;
	void *drawarea	= win->drawArea;

	SaveDrawArea(
		drawarea,
		memory,
		win->left,
		win->top,
		win->right,
		win->bottom
	);
}

static void _RestoreDrawArea(
	Window *win
)
{
	void *memory 	= win->memory;
	void *drawarea	= win->drawArea;

	RestoreDrawArea(
		drawarea,
		memory,
		win->left,
		win->top,
		win->right,
		win->bottom
	);
}

/*  API */
WndID CreateWindow(
	AppID	app,
	WndID	parent,
	int 	mode,
	void	*wndProc,
	int		l,
	int		t,
	int		w,
	int		h
)
{
	Window *win;

	if (w <= 0 || h <= 0){
		return NULL;
	}
	
	if (app == NULL){
		return NULL;
	}

	if (mode < 0 || mode > WINMODE_MAX){
		return NULL;
	}

	if (wndProc == NULL){
		return NULL;
	}

	win =(struct Window *) malloc(sizeof(struct Window));
	if (win == NULL)
		return NULL;

	memset(win, 0, sizeof(struct Window));

	/*  general information */	
	win->application = app;
	win->parent	 = parent;
	win->mode 	 = mode;
	win->wndProc = wndProc;
	if (parent){
		/*  get absolute coord */
		win->left	 = l + parent->left;
		win->top	 = t + parent->top;
	}
	else{
		win->left	 = l;
		win->top	 = t;
	}
	win->right 	 = win->left + w - 1;
	win->bottom  = win->top + h - 1;

	/*  make win is inside screen or inside its parent */
	if (win->left < 0){
		win->left = 0;
	}
	if (win->top < 0){
		win->top = 0;
	}

	/*  Check right & bottom here */
	
	/*  sun window list */
	_Chain_Initialize_empty(
		&win->subWinList
	);

	/*  window drawing area */
	if (parent == NULL){
		switch(mode){
			case MAINWND:
				win->memory 	= malloc(SysBytesPerScreen());
				win->drawArea	= win->memory;
				break;
				
			case SYSMODAL:
			case APPMODAL:
				if (_Chain_Is_empty(&app->WinList)){
					/*  no MAINWIN defined before this window,
					 *  not allowed in emGUI
					 */
					free(win);
					return NULL;
				}
				win->memory 	= malloc(CalcMemGCSize(win->left, win->top, w, h));
				win->drawArea	= ((Window *)(app->WinList.first))->drawArea;
				_SaveDrawArea(win);
				break;

			if (win->memory == NULL){
				/*  have not Insert into */
				free(win);
				return NULL;
			}

			default:
				/* impossible */
				free(win);
				return NULL;
		}
	}
	else{
		win->mode		= SUBWIN;
		win->memory 	= NULL;
		win->drawArea	= parent->drawArea;
	}

		
	if (parent == NULL){
		/*  insert into application window list */
		_Chain_Prepend_unprotected(
			&app->WinList,
			&win->node
		);

		/*  send a message to application */
		PostAppMessage(
			app,
			WNDCREATE,
			0,
			(unsigned32)win
		);
	}
	else{
		/*  insert parent window list */
		_Chain_Prepend_unprotected(
			&parent->subWinList,
			&win->node
		);
	}

	return win;
}

void DestroyWindow(
	WndID	win
)
{
	if (win == NULL || win->application == NULL){
		return;
	}
	
 	/*  Extract from window list,
	 *  may from parent window's subWndList or Application's WindList
	 */	
	_Chain_Extract_unprotected(
		&win->node
	);
	
	if (win->mode == MAINWND){
		/*  send WNDCLOSE to Application, so it will switch draw base
		 */
		PostAppMessage(
			win->application,
			WNDCLOSE,
			0,
			(unsigned32)win
		);
	}
	else if (win->mode == SUBWIN){
		RECT rect = {
			win->left - win->parent->left, 
			win->top - win->parent->top, 
			win->right - win->parent->left, 
			win->bottom - win->parent->top
		};
		
		InvalidateRect(
			win->parent,
			&rect
		);
	}
	else{
		_RestoreDrawArea(win);
	}
	
	/*  Post destroy message to current Window
	 */
	PostMessage(
		win,
		WNDDESTROY,
		0,
		0L
	);
}

/*  really destroy window, called by DefaultWndProc
 */
void _DestroyWindow(
	WndID	win
)
{
	if (win->memory){
		free(win->memory);
	}
	free(win);
}

Window *FindWindow(
	Application *app,
	int			x,
	int			y
)
{
	Window *win, *subwin;
	
	/* 	find window in current application to handle this event,
	 * 	rember, only the first window & its subwindows is searched
	 */
	if (_Chain_Is_empty(&app->WinList)){
		return NULL;
	}

	win = (Window *)app->WinList.first;

	while (win != (Window *)_Chain_Tail(&app->WinList)){
		if (win->left <= x && win->right >= x && win->top <= y && win->bottom >=y){
			goto findsubwin;
		}
		win = (Window *)win->node.next;
	}
	return NULL;

findsubwin:
	if (_Chain_Is_empty(&win->subWinList)){
		return win;
	}

	subwin = (Window *)win->subWinList.first;

	while (subwin != (Window *)_Chain_Tail(&win->subWinList)){
		if (subwin->left <= x && subwin->right >= x && subwin->top <= y && subwin->bottom >=y){
			win = subwin;
			goto findsubwin;
		}
		subwin = (Window *)subwin->node.next;
	}

	return win;
}

void HideWindow(
	WndID	win
)
{
	RECT rect;
	
	if (win == NULL || win->application == NULL)
		return;

	/*  remove it from window list */
	_Chain_Extract_unprotected(
		&win->node
	);
		
	switch (win->mode){
		case MAINWND:
			/*  switch drawing area
			 */
			PostAppMessage(
				win->application,
				WM_HIDE,
				0,
				0L
			);
			break;

		case SYSMODAL:
		case APPMODAL:
			/*  how to restore memory */
			_RestoreDrawArea(win);
			break;

		case SUBWIN:
			rect.left	= win->left - win->parent->left;
			rect.top	= win->top - win->parent->top;
			rect.right	= win->right - win->parent->left;
			rect.bottom = win->bottom - win->parent->top;
			InvalidateRect(
				win->parent,
				&rect
			);
			break;
	}
}

void ShowWindow(
	WndID	win
)
{
	if (win == NULL || win->application == NULL)
		return;
	
	if (win->parent){
		_Chain_Prepend_unprotected(
			&win->parent->subWinList,
			&win->node
		);
	}
	else{
		_Chain_Prepend_unprotected(
			&win->application->WinList,
			&win->node
		);
	}

	switch (win->mode){
		case MAINWND:
			/*  switch drawing area
			 */
			PostAppMessage(
				win->application,
				WM_SHOW,
				0,
				0L
			);
			break;

		case SYSMODAL:
		case APPMODAL:
			/*  how to save memory */
			_SaveDrawArea(win);
			
		case SUBWIN:
			/*  how to redraw window */
			win->invalid_l = 0;
			win->invalid_t = 0;
			win->invalid_r = win->right - win->left;
			win->invalid_b = win->bottom - win->top;
			win->paint_count++;
			PostMessage(
				win,
				WM_PAINT,
				0,
				0L
			);
			break;
	}
}

void InvalidateRect(
	WndID	win,
	LPRECT	lpRect
)
{
	lpRect->left 	+= win->left;
	lpRect->top  	+= win->top;
	lpRect->right 	+= win->left;
	lpRect->bottom 	+= win->top;

	if (win->invalid_l > lpRect->left){
		win->invalid_l = lpRect->left;
	}
	if (win->invalid_t > lpRect->top){
		win->invalid_t = lpRect->top;
	}
	if (win->invalid_b < lpRect->bottom){
		win->invalid_b = lpRect->bottom;
	}
	if (win->invalid_r < lpRect->right){
		win->invalid_r = lpRect->right;
	}

	/*  make invalidate rect is inside Window */

	win->paint_count++;
	PostMessage(
		win,
		WM_PAINT,
		0,
		0L
	);
}