#include <u.h>#include <libc.h>#include <libg.h>#include <panel.h>#include "pldefs.h"typedef struct Scrollbar Scrollbar;struct Scrollbar{	int dir;		/* HORIZ or VERT */	int lo, hi;		/* setting, in screen coordinates */	int buttons;		/* saved mouse buttons for transmittal to scrollee */	Rectangle interior;	Point minsize;};#define	SBWID	15	/* should come from draw.c? */void pl_drawscrollbar(Panel *p){	Scrollbar *sp;	sp=p->data;	sp->interior=pl_outline(p->b, p->r, p->state);	pl_sliderupd(p->b, sp->interior, sp->dir, sp->lo, sp->hi);}int pl_hitscrollbar(Panel *g, Mouse *m){	int oldstate, pos, len, dy;	Point ul, size;	Scrollbar *sp;	sp=g->data;	ul=g->r.min;	size=sub(g->r.max, g->r.min);	pl_interior(g->state, &ul, &size);	oldstate=g->state;	if(m->buttons&OUT && m->buttons&7){		if(m->xy.y<g->r.min.y) m->xy.y=g->r.min.y;		if(m->xy.y>=g->r.max.y) m->xy.y=g->r.max.y-1;		if(ptinrect(m->xy, g->r))			m->buttons&=~OUT;	}	if(sp->dir==HORIZ){		pos=m->xy.x-ul.x;		len=size.x;	}	else{		pos=m->xy.y-ul.y;		len=size.y;	}	if(pos<0) pos=0;	else if(pos>len) pos=len;	if(m->buttons&7){		g->state=DOWN;		if(g->r.min.x<=m->xy.x && m->xy.x<g->r.max.x){			sp->buttons=m->buttons;			switch(m->buttons){			case 1:				dy=pos*(sp->hi-sp->lo)/len;				pl_sliderupd(g->b, sp->interior, sp->dir, sp->lo-dy,					sp->hi-dy);				break;			case 2:				if(g->scrollee && g->scrollee->scroll)					g->scrollee->scroll(g->scrollee, sp->dir,						m->buttons, pos, len);				break;			case 4:				dy=pos*(sp->hi-sp->lo)/len;				pl_sliderupd(g->b, sp->interior, sp->dir, sp->lo+dy,					sp->hi+dy);				break;			}		}	}	else{		if(g->state==DOWN && g->scrollee && g->scrollee->scroll)			g->scrollee->scroll(g->scrollee, sp->dir, sp->buttons,				pos, len);		g->state=UP;	}	if(oldstate!=g->state) pldraw(g, g->b);	return g->state==DOWN;}void pl_typescrollbar(Panel *p, Rune c){	USED(p, c);}Point pl_getsizescrollbar(Panel *p, Point children){	USED(children);	return pl_boxsize(((Scrollbar *)p->data)->minsize, p->state);}void pl_childspacescrollbar(Panel *p, Point *ul, Point *size){	USED(p, ul, size);}/* * Arguments lo, hi and len are in the scrollee's natural coordinates */void pl_setscrollbarscrollbar(Panel *p, int lo, int hi, int len){	Point ul, size;	int mylen;	Scrollbar *sp;	sp=p->data;	ul=p->r.min;	size=sub(p->r.max, p->r.min);	pl_interior(p->state, &ul, &size);	mylen=sp->dir==HORIZ?size.x:size.y;	if(len==0) len=1;	sp->lo=lo*mylen/len;	sp->hi=hi*mylen/len;	if(sp->lo<0) sp->lo=0;	if(sp->lo>=mylen) sp->hi=mylen-1;	if(sp->hi<=sp->lo) sp->hi=sp->lo+1;	if(sp->hi>mylen) sp->hi=mylen;	pldraw(p, p->b);}void plinitscrollbar(Panel *v, int flags){	Scrollbar *sp;	sp=v->data;	v->flags=flags|LEAF;	v->state=UP;	v->draw=pl_drawscrollbar;	v->hit=pl_hitscrollbar;	v->type=pl_typescrollbar;	v->getsize=pl_getsizescrollbar;	v->childspace=pl_childspacescrollbar;	v->setscrollbar=pl_setscrollbarscrollbar;	switch(flags&PACK){	case PACKN:	case PACKS:		sp->dir=HORIZ;		sp->minsize=Pt(0, SBWID);		v->flags|=FILLX;		break;	case PACKE:	case PACKW:		sp->dir=VERT;		sp->minsize=Pt(SBWID, 0);		v->flags|=FILLY;		break;	}	sp->lo=0;	sp->hi=0;	v->kind="scrollbar";}Panel *plscrollbar(Panel *parent, int flags){	Panel *v;	v=pl_newpanel(parent, sizeof(Scrollbar));	plinitscrollbar(v, flags);	return v;}