1 #include <u.h>
2 #include <libc.h>
3 #include <draw.h>
4 #include <mouse.h>
5 #include <frame.h>
6 
7 int
8 frdelete(Frame *f, ulong p0, ulong p1)
9 {
10 	Point pt0, pt1, ppt0;
11 	Frbox *b;
12 	int n0, n1, n, w0;
13 	ulong cn1;
14 	Rectangle r;
15 	int nn0;
16 	Image *col;
17 
18 	if(p0>=f->nchars || p0==p1 || f->b==nil)
19 		return 0;
20 	if(p1 > f->nchars)
21 		p1 = f->nchars;
22 	n0 = _frfindbox(f, 0, 0, p0);
23 	if(n0 == f->nbox)
24 		drawerror(f->display, "off end in frdelete");
25 	n1 = _frfindbox(f, n0, p0, p1);
26 	pt0 = _frptofcharnb(f, p0, n0);
27 	pt1 = frptofchar(f, p1);
28 	if(f->p0 == f->p1)
29 		frtick(f, frptofchar(f, f->p0), 0);
30 	nn0 = n0;
31 	ppt0 = pt0;
32 	_frfreebox(f, n0, n1-1);
33 	f->modified = 1;
34 
35 	/*
36 	 * Invariants:
37 	 *  - pt0 points to beginning, pt1 points to end
38 	 *  - n0 is box containing beginning of stuff being deleted
39 	 *  - n1, b are box containing beginning of stuff to be kept after deletion
40 	 *  - cn1 is char position of n1
41 	 *  - f->p0 and f->p1 are not adjusted until after all deletion is done
42 	 */
43 	b = &f->box[n1];
44 	cn1 = p1;
45 	while(pt1.x!=pt0.x && n1<f->nbox){
46 		_frcklinewrap0(f, &pt0, b);
47 		_frcklinewrap(f, &pt1, b);
48 		n = _frcanfit(f, pt0, b);
49 		if(n==0)
50 			drawerror(f->display, "_frcanfit==0");
51 		r.min = pt0;
52 		r.max = pt0;
53 		r.max.y += f->font->height;
54 		if(b->nrune > 0){
55 			w0 = b->wid;
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 
64 			/* blank remainder of line */
65 			r.min.x = r.max.x;
66 			r.max.x += w0 - b->wid;
67 			if(r.max.x > f->r.max.x)
68 				r.max.x = f->r.max.x;
69 			draw(f->b, r, f->cols[BACK], nil, r.min);
70 		}else{
71 			r.max.x += _frnewwid0(f, pt0, b);
72 			if(r.max.x > f->r.max.x)
73 				r.max.x = f->r.max.x;
74 			col = f->cols[BACK];
75 			if(f->p0<=cn1 && cn1<f->p1)
76 				col = f->cols[HIGH];
77 			draw(f->b, r, col, nil, pt0);
78 			cn1++;
79 		}
80 		_fradvance(f, &pt1, b);
81 		pt0.x += _frnewwid(f, pt0, b);
82 		f->box[n0++] = f->box[n1++];
83 		b++;
84 	}
85 	if(n1==f->nbox && pt0.x!=pt1.x)	/* deleting last thing in window; must clean up */
86 		frselectpaint(f, pt0, pt1, f->cols[BACK]);
87 	if(pt1.y != pt0.y){
88 		Point pt2;
89 
90 		pt2 = _frptofcharptb(f, 32767, pt1, n1);
91 		if(pt2.y > f->r.max.y)
92 			drawerror(f->display, "frptofchar in frdelete");
93 		if(n1 < f->nbox){
94 			int q0, q1, q2;
95 
96 			q0 = pt0.y+f->font->height;
97 			q1 = pt1.y+f->font->height;
98 			q2 = pt2.y+f->font->height;
99 			if(q2 > f->r.max.y)
100 				q2 = f->r.max.y;
101 			draw(f->b, Rect(pt0.x, pt0.y, pt0.x+(f->r.max.x-pt1.x), q0),
102 				f->b, nil, pt1);
103 			draw(f->b, Rect(f->r.min.x, q0, f->r.max.x, q0+(q2-q1)),
104 				f->b, nil, Pt(f->r.min.x, q1));
105 			frselectpaint(f, Pt(pt2.x, pt2.y-(pt1.y-pt0.y)), pt2, f->cols[BACK]);
106 		}else
107 			frselectpaint(f, pt0, pt2, f->cols[BACK]);
108 	}
109 	_frclosebox(f, n0, n1-1);
110 	if(nn0>0 && f->box[nn0-1].nrune>=0 && ppt0.x-f->box[nn0-1].wid>=(int)f->r.min.x){
111 		--nn0;
112 		ppt0.x -= f->box[nn0].wid;
113 	}
114 	_frclean(f, ppt0, nn0, n0<f->nbox-1? n0+1 : n0);
115 	if(f->p1 > p1)
116 		f->p1 -= p1-p0;
117 	else if(f->p1 > p0)
118 		f->p1 = p0;
119 	if(f->p0 > p1)
120 		f->p0 -= p1-p0;
121 	else if(f->p0 > p0)
122 		f->p0 = p0;
123 	f->nchars -= p1-p0;
124 	if(f->p0 == f->p1)
125 		frtick(f, frptofchar(f, f->p0), 1);
126 	pt0 = frptofchar(f, f->nchars);
127 	n = f->nlines;
128 	f->nlines = (pt0.y-f->r.min.y)/f->font->height+(pt0.x>f->r.min.x);
129 	return n - f->nlines;
130 }