gmail-notes-converter

#!/usr/bin/perl

# Gmail notes converter
# by Jon Jensen <jon@endpoint.com>
# 2009-07-20

# Copyright 2009 Jon Jensen. Distributed under the GPLv3 license.
# For details see http://www.gnu.org/licenses/gpl-3.0.html

# When importing e.g. Nokia phone contacts into Gmail, most fields are
# crammed into a single Notes field that is useless in the Android phone
# contacts feature. This script takes Gmail-exported contacts in CSV
# (comma-separated values) format and converts those notes into regular
# phone contact entries, which can then be imported back into Gmail.

# Usage:
# ./gmail-notes-converter input.csv > output.csv

use 5.006; use 5.10.0;
use strict;
use warnings;

my %note2description = (
    Business => 'Work',
    General  => 'Personal',
    Home     => 'Personal',
);

undef $/;
my $file = <>;

my @lines;

# yes, could use Text::CSV, but this works and has no dependencies
while (length($file)) {
    my @fields;

    # all but final field of row
    while (
        $file =~ s{
            \A
            (?:
                "([^"]*)"
                |
                ([^,\r\n]*)
            )
            ,
        }{}xg
    ) {
        push @fields, $1 // $2;
    }

    # final field of row
    if (
        $file =~ s{
            \A
            (?:
                "([^"]*)"
                |
                ([^\r\n]*)
            )
            \r?\n
        }{}x
    ) {
        push @fields, $1 // $2;
    }

    push @lines, \@fields;
}

my @header = @{ shift @lines };
my %header2column;
{
    my $i = 0;
    $header2column{$_} = $i++ for @header;
}

for my $line (@lines) {
    my %description2number;
    my @number;
    my %field;
    my $i = 0;
    for (@$line) {
        $field{$header[$i]} = $_ // '';
        if ($_ and $header[$i] =~ /^Section (\d+) - Description$/) {
            $description2number{$_} = $1;
            $number[$1 - 1] = $_;
        }
        ++$i;
    }
    for (qw( Work Personal Other )) {
        next if defined $description2number{$_};
        push @number, $_;
        my $number = scalar @number;
        $description2number{$_} = $number;
        $field{"Section $number - Description"} = $_;
    }
    if (my $notes = delete $field{Notes}) {
        for my $note (split /\s*\r?\n\s*/, $notes) {
            my ($cat, $type, $value) = ($note =~ /^(\w+)\s+(\w+):\s+(.*)/);
            my $title = "Section $description2number{$note2description{$cat}} - \u$type";
            warn(qq{$field{Name}: Ignoring note value "$value" that conflicts with existing value "$field{$title}"\n}), next
                if $field{$title};
            $field{$title} = $value;
        }
    }
    $line = [ map { $field{$_} } @header ];
}

{
    no warnings 'uninitialized';
    for my $line (\@header, @lines) {
        my $out = join(',', map { /[,\n\r"]/ ? qq{"$_"} : $_ } @$line);
        # trim trailing empty fields to save space
        $out =~ s/,+$//;
        print $out, "\n";
    }
}