v0.1.0 initial commit

tui/list.go

@@ -0,0 +1,99 @@
+package tui
+
+import "github.com/lixenwraith/terminal"
+
+// ListItem represents a single row in a scrollable list
+type ListItem struct {
+	Indent    int  // Left padding in cells
+	Icon      rune // Expand indicator or bullet, 0 = none
+	IconFg    terminal.RGB
+	Check     CheckState // CheckNone to skip checkbox
+	CheckFg   terminal.RGB
+	Text      string
+	TextStyle Style
+}
+
+// ListOpts configures list rendering
+type ListOpts struct {
+	CursorBg  terminal.RGB
+	DefaultBg terminal.RGB
+	IconWidth int // Width reserved for icon, default 2
+}
+
+// List renders scrollable list items within region, returns number of rows rendered
+func (r Region) List(items []ListItem, cursor, scroll int, opts ListOpts) int {
+	if r.H < 1 || len(items) == 0 {
+		return 0
+	}
+
+	iconW := opts.IconWidth
+	if iconW == 0 {
+		iconW = 2
+	}
+
+	rendered := 0
+	for y := 0; y < r.H; y++ {
+		idx := scroll + y
+		if idx >= len(items) {
+			break
+		}
+
+		item := items[idx]
+		isCursor := idx == cursor
+
+		// Row background
+		bg := opts.DefaultBg
+		if isCursor {
+			bg = opts.CursorBg
+		}
+
+		// Clear row
+		for x := 0; x < r.W; x++ {
+			r.Cell(x, y, ' ', terminal.RGB{}, bg, terminal.AttrNone)
+		}
+
+		x := item.Indent
+
+		// Icon
+		if item.Icon != 0 && x < r.W {
+			r.Cell(x, y, item.Icon, item.IconFg, bg, terminal.AttrNone)
+		}
+		x += iconW
+
+		// Checkbox
+		if item.Check != CheckNone || item.CheckFg != (terminal.RGB{}) {
+			if x+3 <= r.W {
+				var ch rune
+				switch item.Check {
+				case CheckNone:
+					ch = ' '
+				case CheckPartial:
+					ch = 'o'
+				case CheckFull:
+					ch = 'x'
+				case CheckPlus:
+					ch = '+'
+				}
+				r.Cell(x, y, '[', item.CheckFg, bg, terminal.AttrNone)
+				r.Cell(x+1, y, ch, item.CheckFg, bg, terminal.AttrNone)
+				r.Cell(x+2, y, ']', item.CheckFg, bg, terminal.AttrNone)
+			}
+			x += 4
+		}
+
+		// Text
+		textStyle := item.TextStyle
+		if textStyle.Bg == (terminal.RGB{}) {
+			textStyle.Bg = bg
+		}
+		text := item.Text
+		if x+RuneLen(text) > r.W {
+			text = Truncate(text, r.W-x)
+		}
+		r.TextStyled(x, y, text, textStyle)
+
+		rendered++
+	}
+
+	return rendered
+}