/*
 *  Roo/E, the Kangaroo Punch Portable GUI Toolkit
 *  Copyright (C) 2022 Scott Duensing
 *
 *  http://kangaroopunch.com
 *
 *
 *  This file is part of Roo/E.
 *
 *  Roo/E is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Affero General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  Roo/E is distributed in the hope that it will be useful, but WITHOUT ANY
 *  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 *  FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 *  details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with Roo/E. If not, see <https://www.gnu.org/licenses/>.
 *
 */


#include "../wmwindow.h"
#include "scroll.h"


uint8_t  __MAGIC_SCROLLABLE = 0;


static void scrollableClickHandler(WidgetT *widget, uint16_t x, uint16_t y, uint8_t event, void *data);
static void scrollableDestroy(struct WidgetS *widget, ...);
static void scrollablePaint(struct WidgetS *widget, ...);


static void scrollableClickHandler(WidgetT *widget, uint16_t x, uint16_t y, uint8_t event, void *data) {
	ScrollableT *s = (ScrollableT *)data;

	(void)widget;
	(void)x;
	(void)y;
	(void)event;

	logWrite("Event from scrollable - %d %d\n", hscrollValueGet(s->scrollh), vscrollValueGet(s->scrollv));

	s->offset.x = hscrollValueGet(s->scrollh);
	s->offset.y = vscrollValueGet(s->scrollv);
}


// Passing "flags" as a default int provides proper alignment for the following va_args list.
ScrollableT *scrollableCreate(int16_t width, int16_t height, int16_t totalWidth, int16_t totalHeight, int flags, ...) {
	ScrollableT *s = NULL;
	SurfaceT    *t = surfaceGet();
	int16_t      w = 0;

	NEW(ScrollableT, s);
	memset(s, 0, sizeof(ScrollableT));

	widgetBaseSet(W(s), __MAGIC_SCROLLABLE, width, height);

	// Set up desired scroll bars.
	s->flags = flags;
	if (s->flags & SCROLLABLE_SCROLL_V) {
		s->scrollv = vscrollCreate(height, scrollableClickHandler, s);
		vscrollRangeSet(s->scrollv, 0, totalHeight- 1);
		w = s->scrollv->base.r.w;  // Used when creating horizontal scroll bar below.
	}
	if (s->flags & SCROLLABLE_SCROLL_H) {
		s->scrollh = hscrollCreate(width - w, scrollableClickHandler, s);
		hscrollRangeSet(s->scrollh, 0, totalWidth - 1);
	}

	// Create scrollable surface.
	s->area  = surfaceCreate(totalWidth, totalHeight);
	if (!s->area) {
		DEL(s);
		return NULL;
	}
	surfaceSet(s->area);
	surfaceClear(GUI_LIGHTBLUE);
	surfaceSet(t);

	return s;
}


static void scrollableDestroy(struct WidgetS *widget, ...) {
	ScrollableT *s = (ScrollableT *)widget;

	// Do not destroy scroll bars here - the parent owns them at this point.
	if (s->area) surfaceDestroy(&s->area);

	DEL(s);
}


static void scrollablePaint(struct WidgetS *widget, ...) {
	ScrollableT *s      = (ScrollableT *)widget;

	if (widgetDirtyGet(widget)) {
		widgetDirtySet(widget, 0);
		// Finish initializing?
		if (s->sizes.x == 0 && s->sizes.y == 0) {
			if (s->scrollh) {
				s->sizes.y = s->base.r.h - s->scrollh->base.r.h;
				s->base.r.h -= s->scrollh->base.r.h;
				windowWidgetAdd(s->base.parent, s->base.r.x, s->base.r.y + s->sizes.y, W(s->scrollh));
			} else {
				s->sizes.y = s->base.r.h;
			}
			if (s->scrollv) {
				s->sizes.x = s->base.r.w - s->scrollv->base.r.w;
				s->base.r.w -= s->scrollv->base.r.w;
				windowWidgetAdd(s->base.parent, s->base.r.x + s->sizes.x, s->base.r.y, W(s->scrollv));
			} else {
				s->sizes.x = s->base.r.w;
			}
		}
		// Blit.
		surfaceBlit(s->base.r.x, s->base.r.y, s->offset.x, s->offset.y, s->sizes.x, s->sizes.y, s->area);
	}
}


RegisterT *scrollableRegister(uint8_t magic) {
	static RegisterT reg = {
		"Scrollable",
		NULL,          // No default on-click handler.
		scrollableDestroy,
		scrollablePaint,
		NULL           // No unregister handler.
	};

	// One-time widget startup code.
	__MAGIC_SCROLLABLE = magic;

	return &reg;
}