"""Read a sample CSV without modifying it; Python 3.9+."""
import csv
import re
import sys


def check(path):
    seen = set()
    total = accepted = excluded = count = 0
    with open(path, encoding="utf-8-sig", newline="") as stream:
        reader = csv.DictReader(stream)
        expected = ["id", "item", "quantity", "unit_price_jpy", "status"]
        if reader.fieldnames != expected:
            raise ValueError("列名または列順が違います")
        for line, row in enumerate(reader, start=2):
            if None in row or any(value is None for value in row.values()):
                raise ValueError(f"{line}行目: 列の数が違います")
            if not row["id"] or row["id"] in seen:
                raise ValueError(f"{line}行目: IDが空か重複しています")
            seen.add(row["id"])
            if not re.fullmatch(r"[1-9][0-9]{0,5}", row["quantity"]):
                raise ValueError(f"{line}行目: 数量は1〜999999の整数です")
            if not re.fullmatch(r"[0-9]{1,9}", row["unit_price_jpy"]):
                raise ValueError(f"{line}行目: 単価は桁区切りなしの0以上の整数です")
            if row["status"] not in {"paid", "cancelled"}:
                raise ValueError(f"{line}行目: 状態が不明です")
            count += 1
            if row["status"] == "paid":
                total += int(row["quantity"]) * int(row["unit_price_jpy"])
                accepted += 1
            else:
                excluded += 1
    return f"行数={count} / 対象={accepted} / 除外={excluded} / 合計={total}円"


if __name__ == "__main__":
    try:
        if len(sys.argv) != 2:
            raise ValueError("使い方: python3 check_orders.py orders.csv")
        print(check(sys.argv[1]))
    except (ValueError, OSError, UnicodeError, csv.Error) as error:
        print(f"確認中止: {error}", file=sys.stderr)
        sys.exit(1)