xref: /plan9/sys/src/libframe/frdelete.c (revision 7dd7cddf99dd7472612f1413b4da293630e6b1bc)
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
frdelete(Frame * f,ulong p0,ulong p1)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 		n = _frcanfit(f, pt0, b);
50 		if(n==0)
51 			drawerror(f->display, "_frcanfit==0");
52 		r.min = pt0;
53 		r.max = pt0;
54 		r.max.y += f->font->height;
55 		if(b->nrune > 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 }
124