More work on LibreOffice support.

internal/presentation/libreoffice.go

@@ -49,3 +49,30 @@ func libreOfficeFocusSnapshot(snapshot atspi.Snapshot, options Options) atspi.Sn
 	}
 	return snapshot
 }
+
+// LibreOfficeCellFormula limits Office presentation to verified Calc cells.
+func LibreOfficeCellFormula(snapshot atspi.Snapshot) string {
+	context := snapshot.LibreOffice
+	if !atspi.IsLibreOfficeProcess(snapshot.ApplicationProcess) || snapshot.Defunct ||
+		snapshot.Role != "table cell" || context == nil || !context.InSpreadsheet || !context.Cell {
+		return ""
+	}
+	return context.Formula
+}
+
+// LibreOfficeFormulaText follows Orca's explicit formula command: non-formula
+// cells report their value, including "empty" when there is no value.
+func LibreOfficeFormulaText(snapshot atspi.Snapshot) string {
+	context := snapshot.LibreOffice
+	if !atspi.IsLibreOfficeProcess(snapshot.ApplicationProcess) || snapshot.Defunct ||
+		snapshot.Role != "table cell" || context == nil || !context.InSpreadsheet || !context.Cell {
+		return "Not in a table."
+	}
+	if formula := LibreOfficeCellFormula(snapshot); formula != "" {
+		return formula
+	}
+	if strings.TrimSpace(context.CellText) != "" {
+		return context.CellText
+	}
+	return "empty"
+}