Rustで日本の最低賃金を扱う minimum_wage_jp クレートの使い方

[dependencies]
minimum_wage_jp = "1"

[dependencies]
minimum_wage_jp = "1"
chrono = "0.4"

use minimum_wage_jp::MinimumWageJp;

let tokyo: u8 = 13;
let rate = MinimumWageJp::rate(tokyo).unwrap();
println!("東京都の最低賃金: {}円", rate);
// => 東京都の最低賃金: 1226円（2025年度改定後）

use chrono::NaiveDate;
use minimum_wage_jp::MinimumWageJp;

let date = NaiveDate::from_ymd_opt(2025, 10, 4).unwrap();
let hokkaido: u8 = 1;
let rate = MinimumWageJp::rate_on_date(date, hokkaido).unwrap();
println!("2025/10/4 北海道: {}円", rate);

use minimum_wage_jp::MinimumWageJp;

let okinawa: u8 = 47;
let rate = MinimumWageJp::rate_for_revision(2025, okinawa).unwrap();
println!("2025年度 沖縄: {}円", rate);

use minimum_wage_jp::{MinimumWageJp, MinimumWageJpCompliance};

let osaka: u8 = 27;
let hourly_yen = 1100;

match MinimumWageJp::is_compliant(osaka, hourly_yen).unwrap() {
    MinimumWageJpCompliance::Compliant => {
        println!("基準を満たしています");
    }
    MinimumWageJpCompliance::Short { shortage_yen, required_yen } => {
        println!("{}円不足（必要額: {}円）", shortage_yen, required_yen);
    }
}

use chrono::NaiveDate;
use minimum_wage_jp::{MinimumWageJp, MinimumWageJpCompliance};

let date = NaiveDate::from_ymd_opt(2025, 11, 1).unwrap();
let aichi: u8 = 23;

let result = MinimumWageJp::is_compliant_on_date(date, aichi, 1050).unwrap();
match result {
    MinimumWageJpCompliance::Compliant => println!("OK"),
    MinimumWageJpCompliance::Short { shortage_yen, required_yen } => {
        println!("不足: {}円（基準: {}円）", shortage_yen, required_yen);
    }
}

use minimum_wage_jp::{MinimumWageJp, MinimumWageJpErr};

match MinimumWageJp::rate(99) {
    Ok(rate) => println!("{}円", rate),
    Err(MinimumWageJpErr::InvalidPrefCode(code)) => {
        eprintln!("無効な都道府県コード: {}", code);
    }
    Err(MinimumWageJpErr::DatasetNotFoundForDate { date, prev, next }) => {
        eprintln!("{}のデータがありません", date);
        // prev / next に隣接するデータセットの情報が入る
    }
    Err(MinimumWageJpErr::DatasetNotFoundForYear { year }) => {
        eprintln!("{}年度のデータがありません", year);
    }
}

2025/09/30 → 2024年度の金額
2025/10/01 → 多くの都道府県で2025年度の金額に切り替わる
2025/10/04 → 北海道も2025年度の金額に切り替わる

use minimum_wage_jp::{MinimumWageJp, MinimumWageJpCompliance};

fn validate_job_posting(pref_code: u8, hourly_wage: u32) -> Result<(), String> {
    match MinimumWageJp::is_compliant(pref_code, hourly_wage) {
        Ok(MinimumWageJpCompliance::Compliant) => Ok(()),
        Ok(MinimumWageJpCompliance::Short { shortage_yen, required_yen }) => {
            Err(format!(
                "時給{}円は最低賃金{}円を{}円下回っています",
                hourly_wage, required_yen, shortage_yen
            ))
        }
        Err(e) => Err(format!("判定エラー: {}", e)),
    }
}

use minimum_wage_jp::MinimumWageJp;

fn print_all_rates() {
    let pref_names = [
        "北海道", "青森県", "岩手県", "宮城県", "秋田県",
        "山形県", "福島県", "茨城県", "栃木県", "群馬県",
        "埼玉県", "千葉県", "東京都", "神奈川県", "新潟県",
        "富山県", "石川県", "福井県", "山梨県", "長野県",
        "岐阜県", "静岡県", "愛知県", "三重県", "滋賀県",
        "京都府", "大阪府", "兵庫県", "奈良県", "和歌山県",
        "鳥取県", "島根県", "岡山県", "広島県", "山口県",
        "徳島県", "香川県", "愛媛県", "高知県", "福岡県",
        "佐賀県", "長崎県", "熊本県", "大分県", "宮崎県",
        "鹿児島県", "沖縄県",
    ];

    for (i, name) in pref_names.iter().enumerate() {
        let code = (i + 1) as u8;
        if let Ok(rate) = MinimumWageJp::rate(code) {
            println!("{}: {}円", name, rate);
        }
    }
}

use minimum_wage_jp::MinimumWageJp;

fn calc_diff(pref: u8, year: u16) -> Option<i32> {
    let current = MinimumWageJp::rate_for_revision(year, pref).ok()? as i32;
    let previous = MinimumWageJp::rate_for_revision(year - 1, pref).ok()? as i32;
    Some(current - previous)
}

// 東京都の2024→2025年度の差額
if let Some(diff) = calc_diff(13, 2025) {
    println!("東京都: +{}円", diff);
}