Add shared internal UI toolkit for both readers

internalui/grid/grid.go

@@ -0,0 +1,60 @@
+// Copyright (c) 2026 Storm Dragon
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+// Package grid owns selection movement and announcements for both form layouts.
+package grid
+
+import (
+	"git.stormux.org/storm/screenreader-common/internalui/message"
+	"strconv"
+)
+
+// Move navigates the filtered positions, preserving the column where possible.
+// The host maps the returned position back to its stable item identity.
+func Move(position, count, columns int, key string) (int, bool) {
+	if count <= 0 || columns <= 0 {
+		return position, false
+	}
+	switch key {
+	case "left":
+		position = max(0, position-1)
+	case "right":
+		position = min(count-1, position+1)
+	case "up":
+		if position >= columns {
+			position -= columns
+		}
+	case "down":
+		if position/columns < (count-1)/columns {
+			position = min(count-1, position+columns)
+		}
+	case "home":
+		position = 0
+	case "end":
+		position = count - 1
+	case "pageup":
+		position = max(0, position-columns*5)
+	case "pagedown":
+		position = min(count-1, position+columns*5)
+	default:
+		return position, false
+	}
+	return position, true
+}
+
+// Describe is shared speech policy. Layouts choose which optional details to
+// request; localization belongs to the session, never to a global catalog.
+func Describe(label string, position, count, columns int, coordinates, itemPosition bool, messages message.Messages) string {
+	row, column := strconv.Itoa(position/columns+1), strconv.Itoa(position%columns+1)
+	item, total := strconv.Itoa(position+1), strconv.Itoa(count)
+	switch {
+	case coordinates && itemPosition:
+		return messages.Format("{0}. row {1}, column {2}. {3} of {4}", label, row, column, item, total)
+	case coordinates:
+		return messages.Format("{0}. row {1}, column {2}", label, row, column)
+	case itemPosition:
+		return messages.Format("{0}. {1} of {2}", label, item, total)
+	default:
+		return label
+	}
+}