bech32-decode ( bech32 checksum -- hrp data )

Vocabulary

bech32.private

Inputs

bech32	an object
checksum	an object

Outputs

hrp	an object
data	an object

Definition

USING: ascii combinators.short-circuit kernel math math.order
sequences ;

IN: bech32.private

: bech32-decode ( bech32 checksum -- hrp data )
    over {
        [ [ 33 126 between? not ] any? ]
        [ [ dup >lower = ] [ dup >upper = ] bi or not ]
    } 1||
    [ 2drop f f ] [
        swap >lower 49 over last-index {
            [ dup not ]
            [ dup 1 83 between? not ]
            [ 2dup [ length ] [ 7 + ] bi* < ]
        } 0||
        [ 3drop f f ] [
            cut rest [
                {
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    15
                    f
                    10
                    17
                    21
                    20
                    26
                    30
                    7
                    5
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    f
                    29
                    f
                    ~24 more~
                } nth 255 or
            ] B{ } map-as dup [ 255 = ] any?
            [ 3drop f f ] [
                rot [ 2dup ] dip bech32-checksum?
                [ 6 head* ] [ 2drop f f ] if
            ] if
        ] if
    ] if ;