import os.path
import sys
from argparse import ArgumentError
import sqlite3


def get_records(records):

    extracted = []

    with open(records, 'r', encoding='utf-8') as file:
        for line in file:
            line = line.strip('\n')
            values = line.split(',', 3)
            values[0] = values[0][8:] + "." + values[0][5:7] + "." + values[0][0:4]
            values[3] = values[3].strip('"')
            extracted.append(tuple(values))

    return extracted


def get_estimates(estimates):

    extracted = []

    with open(estimates, 'r', encoding='utf-8') as file:
        for line in file:
            line = line.strip('\n')
            values = line.split(',', 1)
            extracted.append(tuple(values))

    expanded = [extracted[0]]
    for i, row in enumerate(extracted[1:]):
        next_month = f'{int(expanded[-1][0][5:7]) + 1:02d}' if int(expanded[-1][0][5:7]) < 12 else "01"
        next_date = f'{expanded[-1][0][:4] if int(expanded[-1][0][5:7]) < 12 else f'{int(expanded[-1][0][:4]) + 1:04d}'}-{next_month}'

        while(next_date != row[0]):
            expanded.append((next_date, None))
            next_month = f'{int(expanded[-1][0][5:7]) + 1:02d}' if int(expanded[-1][0][5:7]) < 12 else "01"
            next_date = f'{expanded[-1][0][:4] if int(expanded[-1][0][5:7]) < 12 else f'{int(expanded[-1][0][:4]) + 1:04d}'}-{next_month}'

        expanded.append(row)

    estimates = list(zip([int(r[0][:4]) for r in expanded][::3], [int(r[0][5:])//3 + 1 for r in expanded][::3], [r[1] for r in expanded][::3], [r[1] for r in expanded][1::3], [r[1] for r in expanded][2::3]))
    estimates = list(filter(lambda e: not (e[2] == '' and e[3] == '' and e[4] == ''), estimates))
    return estimates


def main():
    if len(sys.argv) != 4:
        raise ArgumentError(argument=None, message='Usage: python3 populate.py <userdb> <records> <estimates>')

    userdb = sys.argv[1]
    records_file = sys.argv[2]
    estimates_file = sys.argv[3]

    if not os.path.exists(userdb):
        raise ArgumentError(argument=None, message='userdb must exist')

    if not os.path.exists(records_file):
        raise ArgumentError(argument=None, message=f'records file does not exist: {records_file}')

    if not os.path.exists(estimates_file):
        raise ArgumentError(argument=None, message=f'estimates file does not exist: {estimates_file}')
    
    print("reading data...")

    records = get_records(records_file)
    estimates = get_estimates(estimates_file)

    db = sqlite3.connect(userdb)
    db_cursor = db.cursor()
    
    print("inserting records...")
    db_cursor.executemany("INSERT INTO records(date, start, end, comment) VALUES (?,?,?,?)", records)
    print("inserting estimates...")
    db_cursor.executemany("INSERT INTO estimates(year, quarter, estimate_0, estimate_1, estimate_2) VALUES (?,?,?,?,?)", estimates)
    
    print("committing...")
    db.commit()
    db_cursor.close()
    db.close()

    print("Records and estimates populated")


if __name__ == '__main__':
    main()