C# - Intercetion point on lines

I have a list of all the green lines( it is Three lines which is offsetted in two directions)
How can I, With a C# scropt find the intercetion Points of the lines, which are actually crossing, not the intercetion Points if the lines are extended. How can I collect which lines that are actually crossing?

See attached.
curve_intersections.gh (7.2 KB)

Two ways: as lines or as curves.