sys/src/libframe/frdelete.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <draw.h>
   4 #include <thread.h>
   5 #include <mouse.h>
   6 #include <frame.h>
   7
   8 int
   9 frdelete(Frame *f, ulong p0, ulong p1)
  10 {
  11         Point pt0, pt1, ppt0;
  12         Frbox *b;
  13         int n0, n1, n;
  14         ulong cn1;
  15         Rectangle r;
  16         int nn0;
  17         Image *col;
  18
  19         if(p0>=f->nchars || p0==p1 || f->b==nil)
  20                 return 0;
  21         if(p1 > f->nchars)
  22                 p1 = f->nchars;
  23         n0 = _frfindbox(f, 0, 0, p0);
  24         if(n0 == f->nbox)
  25                 drawerror(f->display, "off end in frdelete");
  26         n1 = _frfindbox(f, n0, p0, p1);
  27         pt0 = _frptofcharnb(f, p0, n0);
  28         pt1 = frptofchar(f, p1);
  29         if(f->p0 == f->p1)
  30                 frtick(f, frptofchar(f, f->p0), 0);
  31         nn0 = n0;
  32         ppt0 = pt0;
  33         _frfreebox(f, n0, n1-1);
  34         f->modified = 1;
  35
  36         /*
  37          * Invariants:
  38          *  - pt0 points to beginning, pt1 points to end
  39          *  - n0 is box containing beginning of stuff being deleted
  40          *  - n1, b are box containing beginning of stuff to be kept after deletion
  41          *  - cn1 is char position of n1
  42          *  - f->p0 and f->p1 are not adjusted until after all deletion is done
  43          */
  44         b = &f->box[n1];
  45         cn1 = p1;
  46         while(pt1.x!=pt0.x && n1<f->nbox){
  47                 _frcklinewrap0(f, &pt0, b);
  48                 _frcklinewrap(f, &pt1, b);
  49                 r.min = pt0;
  50                 r.max = pt0;
  51                 r.max.y += f->font->height;
  52                 if(b->nrune > 0){
  53                         n = _frcanfit(f, pt0, b);
  54                         if(n==0)
  55                                 drawerror(f->display, "_frcanfit==0");
  56                         if(n != b->nrune){
  57                                 _frsplitbox(f, n1, n);
  58                                 b = &f->box[n1];
  59                         }
  60                         r.max.x += b->wid;
  61                         draw(f->b, r, f->b, nil, pt1);
  62                         cn1 += b->nrune;
  63                 }else{
  64                         r.max.x += _frnewwid0(f, pt0, b);
  65                         if(r.max.x > f->r.max.x)
  66                                 r.max.x = f->r.max.x;
  67                         col = f->cols[BACK];
  68                         if(f->p0<=cn1 && cn1<f->p1)
  69                                 col = f->cols[HIGH];
  70                         draw(f->b, r, col, nil, pt0);
  71                         cn1++;
  72                 }
  73                 _fradvance(f, &pt1, b);
  74                 pt0.x += _frnewwid(f, pt0, b);
  75                 f->box[n0++] = f->box[n1++];
  76                 b++;
  77         }
  78         if(n1==f->nbox && pt0.x!=pt1.x) /* deleting last thing in window; must clean up */
  79                 frselectpaint(f, pt0, pt1, f->cols[BACK]);
  80         if(pt1.y != pt0.y){
  81                 Point pt2;
  82
  83                 pt2 = _frptofcharptb(f, 32767, pt1, n1);
  84                 if(pt2.y > f->r.max.y)
  85                         drawerror(f->display, "frptofchar in frdelete");
  86                 if(n1 < f->nbox){
  87                         int q0, q1, q2;
  88
  89                         q0 = pt0.y+f->font->height;
  90                         q1 = pt1.y+f->font->height;
  91                         q2 = pt2.y+f->font->height;
  92                         if(q2 > f->r.max.y)
  93                                 q2 = f->r.max.y;
  94                         draw(f->b, Rect(pt0.x, pt0.y, pt0.x+(f->r.max.x-pt1.x), q0),
  95                                 f->b, nil, pt1);
  96                         draw(f->b, Rect(f->r.min.x, q0, f->r.max.x, q0+(q2-q1)),
  97                                 f->b, nil, Pt(f->r.min.x, q1));
  98                         frselectpaint(f, Pt(pt2.x, pt2.y-(pt1.y-pt0.y)), pt2, f->cols[BACK]);
  99                 }else
 100                         frselectpaint(f, pt0, pt2, f->cols[BACK]);
 101         }
 102         _frclosebox(f, n0, n1-1);
 103         if(nn0>0 && f->box[nn0-1].nrune>=0 && ppt0.x-f->box[nn0-1].wid>=(int)f->r.min.x){
 104                 --nn0;
 105                 ppt0.x -= f->box[nn0].wid;
 106         }
 107         _frclean(f, ppt0, nn0, n0<f->nbox-1? n0+1 : n0);
 108         if(f->p1 > p1)
 109                 f->p1 -= p1-p0;
 110         else if(f->p1 > p0)
 111                 f->p1 = p0;
 112         if(f->p0 > p1)
 113                 f->p0 -= p1-p0;
 114         else if(f->p0 > p0)
 115                 f->p0 = p0;
 116         f->nchars -= p1-p0;
 117         if(f->p0 == f->p1)
 118                 frtick(f, frptofchar(f, f->p0), 1);
 119         pt0 = frptofchar(f, f->nchars);
 120         n = f->nlines;
 121         f->nlines = (pt0.y-f->r.min.y)/f->font->height+(pt0.x>f->r.min.x);
 122         return n - f->nlines;
 123 }