use warnings;
use strict;
use Data::Dump qw/dd pp/;

my @array1 = ('ux_prim_clk', 'ux_side_clk', 'ux_xtal_frm_refclk');
my @array2 = ('ccu_ux_xtal_frm_refclk_ack', 'ibbs_ux_prim_clkack',
	'sbr_ux_side_clkack'); 

my @aoa1 = map { [ split /_/, $_ ] } @array1;
my @output;
# Using @array2 for the basis of ordering, so loop over that first
for my $a2 ( map { [ split /_/, $_ ] } @array2 ) {
	#print "##### "; dd $a2; # debug
	# Now look through @array1 for the best match
	my ($highest_match, $highest_match_at_a1idx) = (-1);
	for my $i ( 0 .. $#aoa1 ) { # in this loop, keep track of index
		my $a1 = $aoa1[$i];
		# The following code relies on @$a1 >= @$a2, so check that
		if ( @$a2 < @$a1 ) { warn "Skipping ".pp($a2, $a1); next }
		# Try matching $a1 against $a2 at different offsets
		for my $offset ( 0 .. @$a2 - @$a1 ) {
			my $match = 0;
			# Count the number of matching elements at each offset
			for my $j ( 0 .. $#$a1 ) {
				if ( $a2->[$offset+$j] eq $a1->[$j] ) { $match++ }
				else { last } # failed to match, stop looking
			}
			# If this index and offset matches better, record that
			if ( $match && $match > $highest_match ) {
				#dd $a2, $offset, $a1, $match; # debug
				$highest_match = $match;
				$highest_match_at_a1idx = $i;
			}
		}
	}
	if ( defined $highest_match_at_a1idx )
		{ push @output, $array1[$highest_match_at_a1idx] }
	else { warn "Failed to find match for ".pp($a2) }
}

dd @array1; dd @array2; dd @output;

__END__

("ux_prim_clk", "ux_side_clk", "ux_xtal_frm_refclk")
(
  "ccu_ux_xtal_frm_refclk_ack",
  "ibbs_ux_prim_clkack",
  "sbr_ux_side_clkack",
)
("ux_xtal_frm_refclk", "ux_prim_clk", "ux_side_clk")