Regex Date Broken Down

(
    (
        (
            (
                [1-9]
            )
            |
            (
                [0-2][0-9]
            )
            |
            (
                3[01]
            )
        )
        \.
        (
            (
                0[13578]
            )
            |
            (
                [13578]
            )
            |
            (
                1[02]
            )
        )
    )
    |
    (
        (
            (
                [1-9]
            )
            |
            (
                [0-2][0-9]
            )
            |
            (
                30
            )
        )
        \.
        (
            (
                0[469]
            )
            |
            (
                [469]
            )
            |
            (
                11
            )
        )
    )
    |
    (
        (
            (
                [1-9]
            )
            |
            (
                [0-2][0-9]
            )
        )
        \.
        (
            2|02
        )
    )
)
\.
\d{4}