from typing import List
from random import randint

import pandas as pd

from .exceptions import InvalidNameOrTypeHeaderException
from ..students.models import Student


def check_columns(df: pd.DataFrame, columns: List[str]) -> bool:
    flag = True
    col_types = ['object', 'object', 'int', 'int']
    print(df.dtypes['first_name'])
    for name, col_type in zip(columns, col_types):
        if name not in df and df.dtypes[name].startswith(col_type):
            flag = False
            break

    return flag


def parse_csv(file) -> List[Student]:
    df = pd.read_csv(file)
    columns = ['first_name', 'last_name', 'index', 'mode']

    if not check_columns(df, columns):
        raise InvalidNameOrTypeHeaderException

    students = []
    for _, item in df.iterrows():
        data = {}
        for c in columns:
            data[c] = item[c]
        data['email'] = f'student{randint(1, 300_000)}@gmail.com'
        students.append(Student(**data))

    return students