// Copyright status: this file is in the public domain.

#include <stdlib.h>

#include "lx.h"

#include "internal.h"

typedef struct priv_draw_line PRIV_DRAW_LINE;

#define BATCHSIZE 100
struct priv_draw_line {
  LX_XID d;
  LX_XID gc;
  int nsegs;
  LX_SEGMENT segs[BATCHSIZE];
  } ;

static void *chain_draw_line_start(LX_CONN *xc __attribute__((__unused__)))
{
 PRIV_DRAW_LINE *p;

 p = malloc(sizeof(PRIV_DRAW_LINE));
 p->d = LX_WINDOW_None;
 p->gc = LX_GC_None;
 p->nsegs = 0;
 return(p);
}

static void chain_draw_line_done(LX_CONN *xc, void *pv)
{
 PRIV_DRAW_LINE *p;

 p = pv;
 lx__PolySegment_inbatch(xc,p->d,p->gc,p->nsegs,&p->segs[0]);
 free(p);
}

static CHAINER chain_draw_line = CHAINER_INIT(draw_line);

static void chain_draw_line_changed(LX_CONN *xc, void *pv)
{
 PRIV_DRAW_LINE *p;

 p = pv;
 if (p->d != LX_WINDOW_None) lx__PolySegment_inbatch(xc,p->d,p->gc,p->nsegs,&p->segs[0]);
 p->nsegs = 0;
}

void lx_draw_line(LX_CONN *xc, LX_XID d, LX_XID gc, int x1, int y1, int x2, int y2)
{
 LX_SEGMENT *s;
 PRIV_DRAW_LINE *p;

 if ((x1 < -32768) || (x1 > 32767) || (y1 < -32768) || (y1 > 32767) ||
     (x2 < -32768) || (x2 > 32767) || (y2 < -32768) || (y2 > 32767) )
  { lx__bad_call(xc,"lx_draw_line");
    return;
  }
 p = lx__chainable(xc,&chain_draw_line);
 if (! p)
  { lx__nomem_fail(xc);
    return;
  }
 if ((p->d != d) || (p->gc != gc) || (p->nsegs >= BATCHSIZE))
  { chain_draw_line_changed(xc,p);
    p->d = d;
    p->gc = gc;
  }
 s = &p->segs[p->nsegs++];
 s->x1 = x1;
 s->y1 = y1;
 s->x2 = x2;
 s->y2 = y2;
}