use strict;
use warnings;

use Test::More;
use Test::NoWarnings;

use Data::Dump qw(pp);

my @Tests = (

    'all valid strings',
    [ qq{"hello"},                     'Valid String' ],
    [ qq{"hi 'Hello'"},                'Valid String' ],
    [ qq{"Hey there\n"},               'Valid String' ],
    [ qq{"hi1 \x10"},                  'Valid String' ],
    [ qq{"hi2 \x3A"},                  'Valid String' ],
    [ qq{"hi\thow\tare\tyou\tdoing"},  'Valid String' ],

    'various invalid strings',
    [ qq{'bad"},                     'Close the string!' ],
    [ qq{"bad},                      'Close the string!' ],
    [ qq{"multi-line bad\nstring"},  'Invalid char'      ],
    [ qq{"inner-"-bad"},             'Invalid char'      ],
    [ qq{"bad escape \\"},           'Invalid escape'    ],

    );  # end array @Tests

my @additional = qw(Test::NoWarnings);  # each of these adds 1 test
plan 'tests' => (scalar grep { ref eq 'ARRAY' } @Tests)
              + @additional
              ;

VECTOR:
for my $ar_vector (@Tests) {

    if (not ref $ar_vector) {
        note $ar_vector;
        next VECTOR;
        }

    my ($string, $expected) = @$ar_vector;

    my $got = classify($string);

    is $got, $expected, sprintf "'%s' -> $expected", pp $string;

    }  # end for VECTOR

exit;

# function(s) under test ###########################################

sub classify {

    my ($string,
        ) = @_;

    # placeholder regexes.
    my $rx_valid            = qr{ \A " [^"\\]* (?: \\. [^"\\]* )* " \z }xms;
    my $rx_close_the_string = qr{ .* }xms;  # always true for development
    my $rx_invalid_char     = qr{ .* }xms;
    my $rx_invalid_scape    = qr{ .* }xms;

    return
        $string =~ $rx_valid            ? 'Valid String'      :
        $string =~ $rx_close_the_string ? 'Close the string!' :
        $string =~ $rx_invalid_char     ? 'Invalid char'      :
        $string =~ $rx_invalid_scape    ? 'Invalid escape'    :
        die "unclassifyable string ", pp $string
        ;

    }  # end sub classify()