import json
import sys

def valid_solution(s):
    if len(s) != 81 or not all(c in "123456789" for c in s):
        return False

    rows = [s[i * 9:(i + 1) * 9] for i in range(9)]
    cols = ["".join(s[r * 9 + c] for r in range(9)) for c in range(9)]
    boxes = []

    for br in range(3):
        for bc in range(3):
            box = ""
            for r in range(3):
                for c in range(3):
                    box += s[(br * 3 + r) * 9 + (bc * 3 + c)]
            boxes.append(box)

    return all(set(unit) == set("123456789") for unit in rows + cols + boxes)

def validate(path):
    ids = set()
    n = 0

    with open(path, "r", encoding="utf-8") as f:
        for line_no, line in enumerate(f, start=1):
            row = json.loads(line)

            required = {"id", "question", "answer", "er", "ep", "ed"}
            missing = required - set(row)
            if missing:
                raise ValueError(f"Line {line_no}: missing fields {missing}")

            pid = row["id"]
            question = row["question"]
            answer = row["answer"]

            if pid in ids:
                raise ValueError(f"Line {line_no}: duplicate id {pid}")
            ids.add(pid)

            if len(question) != 81:
                raise ValueError(f"Line {line_no}: question length is not 81")

            if any(c not in ".123456789" for c in question):
                raise ValueError(f"Line {line_no}: invalid character in question")

            if len(answer) != 81:
                raise ValueError(f"Line {line_no}: answer length is not 81")

            if not valid_solution(answer):
                raise ValueError(f"Line {line_no}: invalid Sudoku answer")

            for i, c in enumerate(question):
                if c != "." and answer[i] != c:
                    raise ValueError(f"Line {line_no}: answer does not respect givens")

            n += 1

    print(f"OK: validated {n} puzzles")

if __name__ == "__main__":
    validate(sys.argv[1])