init: pristine aerc 0.20.0 source

lib/ui/context.go

@@ -0,0 +1,133 @@
+package ui
+
+import (
+	"fmt"
+
+	"git.sr.ht/~rockorager/vaxis"
+)
+
+// A context allows you to draw in a sub-region of the terminal
+type Context struct {
+	window    vaxis.Window
+	x, y      int
+	onPopover func(*Popover)
+}
+
+func (ctx *Context) Width() int {
+	width, _ := ctx.window.Size()
+	return width
+}
+
+func (ctx *Context) Height() int {
+	_, height := ctx.window.Size()
+	return height
+}
+
+// returns the vaxis Window for this context
+func (ctx *Context) Window() vaxis.Window {
+	return ctx.window
+}
+
+func NewContext(vx *vaxis.Vaxis, p func(*Popover)) *Context {
+	win := vx.Window()
+	return &Context{win, 0, 0, p}
+}
+
+func (ctx *Context) Subcontext(x, y, width, height int) *Context {
+	if x < 0 || y < 0 {
+		panic(fmt.Errorf("Attempted to create context with negative offset"))
+	}
+	win := ctx.window.New(x, y, width, height)
+	return &Context{win, ctx.x + x, ctx.y + y, ctx.onPopover}
+}
+
+func (ctx *Context) SetCell(x, y int, ch rune, style vaxis.Style) {
+	width, height := ctx.window.Size()
+	if x >= width || y >= height {
+		// no-op when dims are inadequate
+		return
+	}
+	ctx.window.SetCell(x, y, vaxis.Cell{
+		Character: vaxis.Character{
+			Grapheme: string(ch),
+		},
+		Style: style,
+	})
+}
+
+func (ctx *Context) Printf(x, y int, style vaxis.Style,
+	format string, a ...interface{},
+) int {
+	width, height := ctx.window.Size()
+
+	if x >= width || y >= height {
+		// no-op when dims are inadequate
+		return 0
+	}
+
+	str := fmt.Sprintf(format, a...)
+
+	buf := StyledString(str)
+	ApplyAttrs(buf, style)
+
+	old_x := x
+
+	newline := func() bool {
+		x = old_x
+		y++
+		return y < height
+	}
+	for _, sr := range buf.Cells {
+		switch sr.Grapheme {
+		case "\n":
+			if !newline() {
+				return buf.Len()
+			}
+		case "\r":
+			x = old_x
+		default:
+			ctx.window.SetCell(x, y, sr)
+			x += sr.Width
+			if x == old_x+width {
+				if !newline() {
+					return buf.Len()
+				}
+			}
+		}
+	}
+
+	return buf.Len()
+}
+
+func (ctx *Context) Fill(x, y, width, height int, rune rune, style vaxis.Style) {
+	win := ctx.window.New(x, y, width, height)
+	win.Fill(vaxis.Cell{
+		Character: vaxis.Character{
+			Grapheme: string(rune),
+			Width:    1,
+		},
+		Style: style,
+	})
+}
+
+func (ctx *Context) SetCursor(x, y int, style vaxis.CursorStyle) {
+	ctx.window.ShowCursor(x, y, style)
+}
+
+func (ctx *Context) HideCursor() {
+	ctx.window.Vx.HideCursor()
+}
+
+func (ctx *Context) Popover(x, y, width, height int, d Drawable) {
+	ctx.onPopover(&Popover{
+		x:       ctx.x + x,
+		y:       ctx.y + y,
+		width:   width,
+		height:  height,
+		content: d,
+	})
+}
+
+func (ctx *Context) Size() (int, int) {
+	return ctx.window.Size()
+}