#!/usr/bin/perl -w

use strict;

my $VERSION = '1.00';

=pod

NAME

	elect_zips - Utility to elect a winning city/state for each ZIP code based on patron data

USAGE

	psql -U evergreen -A -t -F $'\t' -c 'SELECT city, state, post_code FROM actor.usr_address' > raw-csz.tsv
	elect_zips < raw-csz.tsv > winning-zips.tsv

NOTES

	Given input like "Miami Springs\tFL\t33166\n" derived from patron addresses,
	this utility will print a city and state for each zip that has the maximum
	number of occurrences. (It does not attempt to break ties. If there is a tie,
	the city and state that reaches the maximum first will end up winning.)

	You can also feed the output of elect_zips directly into I<enrich_zips --db US.txt --makezips>

=cut

my %zips;

# Go through the input and tally the city-state combinations for each ZIP code
while (<>) {
	chomp;
	(my $city, my $state, my $zip) = split(/\t/) or next;
	next unless $zip =~ m/([\d]{5})/; # If it doesn't have 5 digits in a row, it's not a ZIP
	$zip =~ s/^([\d]{5}).*$/$1/;      # We only want the 5-digit ZIP
	$state = uc($state);
	$city =~ s/^\s+//;
	$city =~ s/\s+$//;
	$zips{$zip}{"$city\t$state"}++;
}

# Pick and print a winner for each ZIP code
foreach(sort keys %zips) {
	my $zip = $_;
	my $max = 0;
	my $citystate = "";
	foreach(keys %{$zips{$zip}}) {
		if ($zips{$zip}{$_} > $max) {
			$max = $zips{$zip}{$_};
			$citystate = $_;
		}
	}
	print "$citystate\t$zip\n";
}