#!/usr/bin/env python3
"""Evaluate grades from a moodle activity grades csv export"""

import argparse
import csv
from datetime import datetime
import locale

# Example: Donnerstag, 16. Oktober 2025
MOODLE_DATE_FORMAT = '%A, %d. %B %Y, %H:%M'


def main():
    """Entry point loading grades and evaluating them"""
    parser = argparse.ArgumentParser()
    parser.add_argument("--points",
                        help="The maximum amount of points for the grades",
                        type=int,
                        default=3)
    parser.add_argument("--scale",
                        help="The scale of the grades",
                        default="0-10")
    parser.add_argument("--locale",
                        help="The locale to use",
                        default="de_DE.utf8")
    parser.add_argument("grades", help="The csv file containing the grades")
    args = parser.parse_args()

    locale.setlocale(locale.LC_ALL, args.locale)

    scale = args.scale.split('-')
    scale = (int(scale[0]), int(scale[1]))

    with open(args.grades, 'r', encoding='utf-8') as grades_files:
        grades_reader = csv.reader(grades_files)
        next(grades_reader)  # skip headers
        grades_data = list(grades_reader)

    grades = {}
    # Collect all first attempts
    for grade in grades_data:
        student = grade[1]
        if grade[5] != '' and (not student in grades or datetime.strptime(
                grades[student][0], MOODLE_DATE_FORMAT) > datetime.strptime(
                    grade[0], MOODLE_DATE_FORMAT)):
            grades[student] = grade

    results = [float(grade[5].replace(',', '.')) for grade in grades.values()]
    mean = sum(results) / len(results)

    print(f'mean: {mean} -> {args.points*(mean-scale[0])/scale[1]}')


if __name__ == '__main__':
    main()