%!PS

% begin included library code
% see https://github.com/Firedrake/postscript-libraries/
/ymd2jd {
    4 dict begin
    aload pop
    /d exch def
    /m exch def
    /y exch def
    /mn m 14 sub 12 idiv def
    y 4800 add mn add 1461 mul 4 idiv
    mn 12 mul neg 2 sub m add 367 mul 12 idiv add
    y 4900 add mn add 100 idiv 3 mul 4 idiv sub
    d add
    32075 sub
    end
} bind def

/test {
    /test.count test.count 1 add def
    {
        /test.pass test.pass 1 add def
    } {
        ( ) print
        test.count (....) cvs print
        (-fail) print
    } ifelse
} bind def

/test.start {
    print (:) print
    /test.pass 0 def
    /test.count 0 def
} bind def

/deepeq {
    2 dict begin
    /a exch def
    /b exch def
    a type b type eq {
        a type /dicttype eq {
            a length b length eq {
                <<
                    a {
                        pop
                        true
                    } forall
                    b {
                        pop
                        true
                    } forall
                >>
                true exch
                {
                    pop
                    dup a exch known {
                        dup b exch known {
                            dup a exch get exch b exch get deepeq not {
                                pop false
                            } if
                        } {
                            false
                        } ifelse
                    } {
                        false
                    } ifelse
                } forall
            } {
                false
            } ifelse
        } {
            a type dup /arraytype eq exch /stringtype eq or {
                a length b length eq {
                    true
                    0 1 a length 1 sub {
                        dup a exch get exch b exch get deepeq not {
                            pop false
                            exit
                        } if
                    } for
                } {
                    false
                } ifelse
            } {
                a b eq
            } ifelse
        } ifelse
    } {
        false
    } ifelse
    end
} bind def

/test.end {
    ( ) print
    test.count 0 gt {
        (Passed ) print
        test.pass (...) cvs print
        (/) print
        test.count (...) cvs print
        ( \() print
        test.pass 100 mul test.count idiv (...) cvs print
        (%\)) print
        (\r\n) print
    } if
} bind def


% end included library code

/parse {
    1 dict begin
    /ds exch def
    [
        ds 0 4 getinterval cvi
        ds 5 2 getinterval cvi
        ds 8 2 getinterval cvi
    ]
    end
} bind def

/datedifference {
    4 dict begin
    parse /d2 exch def
    parse /d1 exch def
    d1 ymd2jd d2 ymd2jd sub 0 gt {
        d1 d2
        /d1 exch def
        /d2 exch def
    } if
    /yd d2 0 get d1 0 get sub def
    /inter [ d2 0 get d1 1 get d1 2 get ] def
    d1 1 get d2 1 get gt
    d1 1 get d2 1 get eq
    d1 2 get d2 2 get gt and or {
        /inter [ d2 0 get 1 sub d1 1 get d1 2 get ] def
        /yd yd 1 sub def
    } if
    [ yd d2 ymd2jd inter ymd2jd sub ]
    end
} bind def

(datedifference) test.start
(2019-02-10) (2022-11-01) datedifference [ 3 264 ] deepeq test
(2020-09-15) (2022-03-29) datedifference [ 1 195 ] deepeq test
test.end