init: pristine aerc 0.20.0 source

lib/ui/string.go

@@ -0,0 +1,142 @@
+package ui
+
+import (
+	"git.sr.ht/~rockorager/vaxis"
+)
+
+func StyledString(s string) *vaxis.StyledString {
+	return state.vx.NewStyledString(s, vaxis.Style{})
+}
+
+// Applies a style to a string. Any currently applied styles will not be overwritten
+func ApplyStyle(style vaxis.Style, str string) string {
+	ss := StyledString(str)
+	d := vaxis.Style{}
+	for i, sr := range ss.Cells {
+		if sr.Style == d {
+			sr.Style = style
+			ss.Cells[i] = sr
+		}
+	}
+	return ss.Encode()
+}
+
+// PadLeft inserts blank spaces at the beginning of the StyledString to produce
+// a string of the provided width
+func PadLeft(ss *vaxis.StyledString, width int) {
+	w := ss.Len()
+	if w >= width {
+		return
+	}
+	cell := vaxis.Cell{
+		Character: vaxis.Character{
+			Grapheme: " ",
+			Width:    1,
+		},
+	}
+	w = width - w
+	cells := make([]vaxis.Cell, 0, len(ss.Cells)+w)
+	for w > 0 {
+		cells = append(cells, cell)
+		w -= 1
+	}
+	cells = append(cells, ss.Cells...)
+	ss.Cells = cells
+}
+
+// PadLeft inserts blank spaces at the end of the StyledString to produce
+// a string of the provided width
+func PadRight(ss *vaxis.StyledString, width int) {
+	w := ss.Len()
+	if w >= width {
+		return
+	}
+	cell := vaxis.Cell{
+		Character: vaxis.Character{
+			Grapheme: " ",
+			Width:    1,
+		},
+	}
+	w = width - w
+	for w > 0 {
+		w -= 1
+		ss.Cells = append(ss.Cells, cell)
+	}
+}
+
+// ApplyAttrs applies the style, and if another style is present ORs the
+// attributes
+func ApplyAttrs(ss *vaxis.StyledString, style vaxis.Style) {
+	for i, cell := range ss.Cells {
+		if style.Foreground != 0 {
+			cell.Style.Foreground = style.Foreground
+		}
+		if style.Background != 0 {
+			cell.Style.Background = style.Background
+		}
+		cell.Style.Attribute |= style.Attribute
+		if style.UnderlineColor != 0 {
+			cell.Style.UnderlineColor = style.UnderlineColor
+		}
+		if style.UnderlineStyle != vaxis.UnderlineOff {
+			cell.Style.UnderlineStyle = style.UnderlineStyle
+		}
+		ss.Cells[i] = cell
+	}
+}
+
+// Truncates the styled string on the right and inserts a '…' as the last
+// character
+func Truncate(ss *vaxis.StyledString, width int) {
+	if ss.Len() <= width {
+		return
+	}
+	cells := make([]vaxis.Cell, 0, len(ss.Cells))
+	total := 0
+	for _, cell := range ss.Cells {
+		if total+cell.Width >= width {
+			// we can't fit this cell so put in our truncator
+			cells = append(cells, vaxis.Cell{
+				Character: vaxis.Character{
+					Grapheme: "…",
+					Width:    1,
+				},
+				Style: cell.Style,
+			})
+			break
+		}
+		total += cell.Width
+		cells = append(cells, cell)
+	}
+	ss.Cells = cells
+}
+
+// TruncateHead truncates the left side of the string and inserts '…' as the
+// first character
+func TruncateHead(ss *vaxis.StyledString, width int) {
+	l := ss.Len()
+	if l <= width {
+		return
+	}
+	offset := l - width
+	cells := make([]vaxis.Cell, 0, len(ss.Cells))
+	cells = append(cells, vaxis.Cell{
+		Character: vaxis.Character{
+			Grapheme: "…",
+			Width:    1,
+		},
+	})
+	total := 0
+	for _, cell := range ss.Cells {
+		total += cell.Width
+		if total < offset {
+			// we always have at least one for our truncator. We
+			// copy this cells style to it so that it retains the
+			// style information from the first printed cell
+			cells[0].Style = cell.Style
+			continue
+		}
+		cells = append(cells, cell)
+	}
+	ss.Cells = cells
+}