<defs>
    <marker id="edge-two-way" markerWidth="2" markerHeight="1" refX="1" refY="0.5" orient="auto">
        <polyline points="0.8,0.3 0.6,0.5 0.8,0.7"/>
        <polyline points="1.2,0.3 1.4,0.5 1.2,0.7"/>
        <polyline points="0.6,0.5 1.4,0.5" />
    </marker>
    <marker id="edge-forward" markerWidth="2" markerHeight="1" refX="1" refY="0.5" orient="auto">
        <polyline points="1.2,0.3 1.4,0.5 1.2,0.7"/>
        <polyline points="0.6,0.5 1.4,0.5"/>
    </marker>
    <marker id="edge-backward" markerWidth="2" markerHeight="1" refX="1" refY="0.5" orient="auto">
        <polyline points="0.8,0.3 0.6,0.5 0.8,0.7"/>
        <polyline points="0.6,0.5 1.4,0.5"/>
    </marker>
    <marker id="edge-none" markerWidth="2" markerHeight="1" refX="1" refY="0.5" orient="auto">
        <polyline points="0.6,0.5 1.4,0.5"/>
    </marker>
</defs>

@code {
    public static string GetMakerMid(DirectionAllowed direction)
    {
        return direction switch
        {
            DirectionAllowed.Both => $"url(#edge-two-way)",
            DirectionAllowed.Forward => $"url(#edge-forward)",
            DirectionAllowed.Backward => $"url(#edge-backward)",
            DirectionAllowed.None => $"url(#edge-none)",
            _ => "",
        };
    }
}
