1package core
2
3import "slices"
4
5func (w *Workspace) band(i int) int { return i / max(w.MaxColumns, 1) }
6func (w *Workspace) sameBand(a, b int) bool { return !w.policy().wraps || w.band(a) == w.band(b) }
7func (w *Workspace) cellX(i int) int {
8 return w.gap() + (i%max(w.MaxColumns, 1))*(w.cellWidth()+w.gap())
9}
10func (w *Workspace) cascadeBands() (n, spacing int) {
11 if len(w.Columns) == 0 || w.Usable.H <= 0 {
12 return 1, 0
13 }
14 return w.band(len(w.Columns)-1) + 1, w.Usable.H
15}
16func (w *Workspace) cellWidth() int {
17 k := max(w.MaxColumns, 1)
18 return max((w.Usable.W-w.gap()*(k+1))/k, 0)
19}
20func (w *Workspace) cellInBand(b int) int {
21 k := max(w.MaxColumns, 1)
22 return min(b*k+w.Focus%k, len(w.Columns)-1)
23}
24func (w *Workspace) focusBand(dir int) bool {
25 i := w.laneNeighbor(dir)
26 if i < 0 {
27 return false
28 }
29 w.unmaximize()
30 w.Focus = i
31 w.Columns[i].Focus = 0
32 if dir < 0 {
33 w.Columns[i].Focus = len(w.Columns[i].Windows) - 1
34 }
35 w.raiseColumns()
36 w.scroll()
37 return true
38}
39func (w *Workspace) cascadeRectsInto(dst []Rect, ignoreFullWidth bool) []Rect {
40 g := w.gap()
41 width := w.cellWidth()
42 rects := slices.Grow(dst[:0], len(w.Columns))[:len(w.Columns)]
43 view := w.View + w.shiftPixels()
44 for i := range w.Columns {
45 r := Rect{X: w.Usable.X + w.cellX(i), Y: w.Usable.Y + g + w.band(i)*w.Usable.H - view, W: width, H: max(w.Usable.H-2*g, 0)}
46 if w.Columns[i].FullWidth && !ignoreFullWidth {
47 r.X = w.Usable.X + g
48 r.W = max(w.Usable.W-2*g, 0)
49 }
50 rects[i] = r
51 }
52 return rects
53}
54
55func (w *Workspace) cascadePoints() []float64 {
56 n, spacing := w.cascadeBands()
57 points := make([]float64, n)
58 for i := range points {
59 points[i] = float64(i * spacing)
60 }
61 return points
62}
63
64func (w *Workspace) cascadeFocus(view int) int {
65 if len(w.Columns) == 0 {
66 return 0
67 }
68 b := min(max(view/max(w.Usable.H, 1), 0), w.band(len(w.Columns)-1))
69 return w.cellInBand(b)
70}
71
72// laneOf is the lane of column i in the overview: its band, or the only
73// lane of a layout that does not wrap.
74func (w *Workspace) laneOf(i int) int {
75 if w.policy().wraps {
76 return w.band(i)
77 }
78 return 0
79}
80
81// laneBounds is the range of columns of a lane, first > last when the lane
82// does not exist. A layout that does not wrap has the whole row as lane 0.
83func (w *Workspace) laneBounds(lane int) (first, last int) {
84 k := len(w.Columns)
85 if w.policy().wraps {
86 k = max(w.MaxColumns, 1)
87 }
88 first = lane * k
89 if lane < 0 || first >= len(w.Columns) {
90 return 0, -1
91 }
92 return first, min(first+k, len(w.Columns)) - 1
93}
94
95// laneNeighbor is the closest column to the focus in the lane d lanes away,
96// the focus's offset in its lane kept; -1 past the first or last lane.
97func (w *Workspace) laneNeighbor(d int) int {
98 lane := w.laneOf(w.Focus)
99 first, _ := w.laneBounds(lane)
100 nfirst, nlast := w.laneBounds(lane + d)
101 if nfirst > nlast {
102 return -1
103 }
104 return min(nfirst+w.Focus-first, nlast)
105}