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| #!/usr/bin/env perl
# payment-check-03.pl
# ペルマート決済審査（Chain of Responsibility版）
# Perl v5.36+, Moo
use v5.36;
use utf8;
use warnings;
use Moo;
binmode STDOUT, ':utf8';
# ===========================================
# 基底クラス: PaymentChecker
# ===========================================
package PaymentChecker {
use Moo;
has 'next_handler' => (
is => 'rw',
predicate => 'has_next_handler',
);
sub set_next ($self, $handler) {
$self->next_handler($handler);
return $handler;
}
sub check ($self, $request) {
return $self->pass_to_next($request);
}
sub pass_to_next ($self, $request) {
if ($self->has_next_handler) {
return $self->next_handler->check($request);
}
return { ok => 1 };
}
}
# ===========================================
# 金額上限チェッカー
# ===========================================
package LimitChecker {
use Moo;
extends 'PaymentChecker';
has 'limit' => (
is => 'ro',
default => 100_000,
);
sub check ($self, $request) {
my $amount = $request->{amount} // 0;
if ($amount >= $self->limit) {
return {
ok => 0,
reason => sprintf('金額が上限（%d円）を超えています', $self->limit),
};
}
return $self->pass_to_next($request);
}
}
# ===========================================
# 有効期限チェッカー
# ===========================================
package ExpiryChecker {
use Moo;
extends 'PaymentChecker';
sub check ($self, $request) {
my $expiry_year = $request->{expiry_year} // 0;
my $expiry_month = $request->{expiry_month} // 0;
my ($current_year, $current_month) = (localtime)[5,4];
$current_year += 1900;
$current_month += 1;
my $is_expired = $expiry_year < $current_year ||
($expiry_year == $current_year && $expiry_month < $current_month);
if ($is_expired) {
return {
ok => 0,
reason => 'カードの有効期限が切れています',
};
}
return $self->pass_to_next($request);
}
}
# ===========================================
# ブラックリストチェッカー
# ===========================================
package BlacklistChecker {
use Moo;
extends 'PaymentChecker';
has 'blacklist' => (
is => 'ro',
default => sub { [] },
);
sub check ($self, $request) {
my $card_number = $request->{card_number} // '';
for my $blacklisted (@{ $self->blacklist }) {
if ($card_number eq $blacklisted) {
return {
ok => 0,
reason => 'このカードは使用できません',
};
}
}
return $self->pass_to_next($request);
}
}
# ===========================================
# 残高チェッカー
# ===========================================
package BalanceChecker {
use Moo;
extends 'PaymentChecker';
has 'balance_db' => (
is => 'ro',
default => sub { {} },
);
sub check ($self, $request) {
my $card_number = $request->{card_number} // '';
my $amount = $request->{amount} // 0;
my $balance = $self->balance_db->{$card_number} // 0;
if ($balance < $amount) {
return {
ok => 0,
reason => '利用可能枠が不足しています',
};
}
return $self->pass_to_next($request);
}
}
# ===========================================
# 不正利用検知チェッカー
# ===========================================
package FraudChecker {
use Moo;
extends 'PaymentChecker';
has 'transaction_log' => (
is => 'ro',
default => sub { {} },
);
has 'threshold' => (
is => 'ro',
default => 3,
);
sub check ($self, $request) {
my $card_number = $request->{card_number} // '';
my $recent_count = $self->transaction_log->{$card_number} // 0;
if ($recent_count >= $self->threshold) {
return {
ok => 0,
reason => '短時間での連続決済を検知しました',
};
}
return $self->pass_to_next($request);
}
}
# ===========================================
# メイン処理
# ===========================================
package main;
# ダミーデータ（学習用）
my %BALANCE_DB = (
'4242424242424242' => 100_000,
'5105105105105100' => 500_000,
);
my %TRANSACTION_LOG = (
'4111111111111111' => 5, # 不正利用の疑い
);
# チェッカーを作成
my $limit_checker = LimitChecker->new(limit => 100_000);
my $expiry_checker = ExpiryChecker->new;
my $blacklist_checker = BlacklistChecker->new(
blacklist => ['4111111111111111', '5500000000000004'],
);
my $balance_checker = BalanceChecker->new(
balance_db => \%BALANCE_DB,
);
my $fraud_checker = FraudChecker->new(
transaction_log => \%TRANSACTION_LOG,
threshold => 3,
);
# チェーンを構築
$limit_checker
->set_next($expiry_checker)
->set_next($blacklist_checker)
->set_next($balance_checker)
->set_next($fraud_checker);
# 審査開始点
my $first_checker = $limit_checker;
# === 実行例 ===
my @test_cases = (
{
name => '正常な決済',
amount => 50_000,
expiry_year => 2028,
expiry_month => 12,
card_number => '5105105105105100',
},
{
name => '金額オーバー',
amount => 200_000,
expiry_year => 2028,
expiry_month => 12,
card_number => '5105105105105100',
},
{
name => '期限切れ',
amount => 50_000,
expiry_year => 2025,
expiry_month => 6,
card_number => '5105105105105100',
},
{
name => 'ブラックリスト',
amount => 50_000,
expiry_year => 2028,
expiry_month => 12,
card_number => '4111111111111111',
},
{
name => '残高不足',
amount => 80_000,
expiry_year => 2028,
expiry_month => 12,
card_number => '4242424242424242', # 10万円の枠に対して8万円
},
);
for my $test (@test_cases) {
say "=== $test->{name} ===";
my $result = $first_checker->check($test);
if ($result->{ok}) {
say "承認: 決済処理に進みます";
}
else {
say "拒否: $result->{reason}";
}
say "";
}
|
