from datetime import datetime, timedelta, date, time
from scrape import scrape
import csv

def time_intersect(start_A, end_A, start_B, end_B):
    """
    accepts 2 timeframe and return the overlap
    :param start_A: datetime
    :param end_A: datetime
    :param start_B: datetime
    :param end_B: datetime
    :return: timedelta
    """
    latest_start = max(start_A, start_B)
    earliest_end = min(end_A, end_B)
    if latest_start <= earliest_end:
        return (earliest_end - latest_start).total_seconds()/3600
    else:
        return 0

def create_datelist(start_A, end_B, time_start, time_end, sat=False, sun=False):
    """
    takes 2 datetime object iterates to all dates in range of the 2 datetime object
    and combine the time_start and time_end to all dates in range. Returns a list of 2 datetime item list

    :param start_A: datetime
    :param end_B: datetime
    :param time_start: int 0 to 23
    :param time_end: int 0 to 23
    :return: datetime
    """
    if time_start > time_end:
        day_offset = 1
    else:
        day_offset = 0
    counter = 0
    datelist = []
    while True:
        if sat and start_A.weekday() == 5:
            datelist.append([datetime.combine(start_A, time(0)),
                             datetime.combine(start_A + timedelta(days=1), time(0))])
        elif sun and start_A.weekday() == 6:
            datelist.append([datetime.combine(start_A, time(0)),
                             datetime.combine(start_A + timedelta(days=1), time(0))])
        elif not sat and not sun:
            datelist.append([datetime.combine(start_A, time(time_start)),
                             datetime.combine(start_A + timedelta(days=day_offset), time(time_end))])

        counter += 1
        start_A += timedelta(days=counter)
        if start_A.date() > end_B.date():
            break
    return datelist

#Sample data from scrape() [[2019-03-19 00:00:00,2019-03-19 06:00:00,Staff name,Client name]] there would 1000+ items
rosters = scrape()
rates = {'am':48.14,
         'pm':52.79,
         'on':34.14,
         'sat':66.77,
         'sun':85.45}
roster_rated = []
for roster in rosters:
    mornings = create_datelist(roster[0],roster[1],6,20)
    evenings = create_datelist(roster[0],roster[1],20,0)
    over_nights = create_datelist(roster[0],roster[1],0,6)

    if roster[1].hour == 0:#adjust for midnight
        roster[1] += timedelta(days=1)
    sat = 0
    sun = 0
    am = 0
    pm = 0
    on = 0
    if roster[0].weekday() == 5:
        saturdays = create_datelist(roster[0], roster[1], 0, 6, sat=True)
        for saturday in saturdays:
            sat += time_intersect(roster[0], roster[1], saturday[0], saturday[1])
    elif roster[0].weekday() == 6:
        sundays = create_datelist(roster[0], roster[1], 0, 6, sun=True)
        for sunday in sundays:
            sun += time_intersect(roster[0], roster[1], sunday[0], sunday[1])
    else:
        for morning in mornings:
            am += time_intersect(roster[0], roster[1], morning[0], morning[1])
        for evening in evenings:
            pm += time_intersect(roster[0], roster[1], evening[0], evening[1])
        for over_night in over_nights:
            on += time_intersect(roster[0], roster[1], over_night[0], over_night[1])


    roster.extend([am,am*rates['am'],pm,pm*rates['pm'],on,on*rates['on'],sat,sat*rates['sat'],sun,sun*rates['sun']])
    roster_rated.append(roster)

with open('roster_rated.csv', 'w', newline='') as f:
    writer = csv.writer(f)
    for each in roster_rated:
        writer.writerow(each)