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package t::Util;

use strict;
use warnings;
use DBI;
use File::Temp qw/tempfile/;
use base 'Exporter';
use Benchmark qw/:hireswallclock/;
use IO::Handle;
use Data::Dumper;

our @EXPORT = qw/capture capture_logger cmpthese/;

BEGIN {
    # cleanup environment
    for my $key (keys %ENV) {
        next unless $key =~ /^DBIX_QUERYLOG_/;
        delete $ENV{$key};
    }
}

my $MYSQLD;
my $POSTGRESQLD;

# for prove -Pt::Util
sub load {
    setup_mysqld();
    setup_postgresql();
}

sub new_dbh {
    my ($fh, $file) = tempfile;
    my $dbh = DBI->connect("dbi:SQLite:dbname=$file",'','', {
        AutoCommit => 1,
        RaiseError => 1,
    });
    return $dbh;
}

sub new_logger {
    bless {}, 't::Util::Logger';
}

sub setup_mysqld {
    return $MYSQLD if $MYSQLD;

    eval { require Test::mysqld; 1 } or return;

    if ($ENV{__TEST_DBIX_QUERYLOG_MYSQLD}) {
        $MYSQLD = eval $ENV{__TEST_DBIX_QUERYLOG_MYSQLD};
    }

    unless ($MYSQLD) {
        $MYSQLD = eval {
            Test::mysqld->new(my_cnf => {
                'skip-networking' => '',
            });
        } or return;

        local $Data::Dumper::Terse  = 1;
        local $Data::Dumper::Indent = 0;
        $ENV{__TEST_DBIX_QUERYLOG_MYSQLD} = Dumper +$MYSQLD;
    }

    return $MYSQLD;
}

sub setup_postgresql {
    return $POSTGRESQLD if $POSTGRESQLD;

    eval { require Test::PostgreSQL; Test::PostgreSQL->VERSION >= 0.1 } or return;

    if ($ENV{__TEST_DBIX_QUERYLOG_POSTGRESQLD}) {
        $POSTGRESQLD = eval $ENV{__TEST_DBIX_QUERYLOG_POSTGRESQLD};
    }

    unless ($POSTGRESQLD) {
        $POSTGRESQLD = eval { Test::PostgreSQL->new() } or return;
        my $dbh = DBI->connect(
            $POSTGRESQLD->dsn(dbname => 'test'), '', '',
            {
                AutoCommit => 1,
                RaiseError => 1,
            },
        ) or die $DBI::errstr;
        # mysql tests use the "user" table name and Pg's "user" is a function.
        # so we don't use table name "user" without quotaion marks in pg tests.
        # but mendo-kusai node sonnomama ni sita.
        $dbh->do('CREATE TABLE "user" ("User" text)');
        $dbh->disconnect;

        local $Data::Dumper::Terse  = 1;
        local $Data::Dumper::Indent = 0;
        $ENV{__TEST_DBIX_QUERYLOG_POSTGRESQLD} = Dumper +$POSTGRESQLD;
    }

    return $POSTGRESQLD;
}

sub capture(&) {
    my ($code) = @_;

    open my $fh, '>', \my $content;
    $fh->autoflush(1);
    local $DBIx::QueryLog::OUTPUT = $fh;
    $code->();
    close $fh;
    return $content;
}

sub capture_logger(&) {
    my ($code) = @_;

    my $content;

    my $logger = DBIx::QueryLog->logger;
    no strict 'refs';
    no warnings 'redefine';
    my $logger_class = ref $logger;
    *{"$logger_class\::log"} = sub {
        my ($class, %p) = @_;
        $content = $p{params};
    };

    $code->();

    return $content;
}

sub cmpthese {
    my $result = Benchmark::timethese(@_);
    for my $value (values %$result) {
        $value->[1] = $value->[2] = $value->[0];
    };
    Benchmark::cmpthese($result);
}

package t::Util::Logger;

sub log {
    die 'fix me';
}

1;