#!/usr/bin/python3

import argparse
from lib.DataStore import DataStore
from lib.TimeSlot import TimeSlot
from lib.ui import convert_to_table
from datetime import datetime


def create_parser():
    # Create the top-level parser
    parser = argparse.ArgumentParser(description="Time tracker.")
    subparsers = parser.add_subparsers(dest="command", help="Sub-command help")

    # Create the parser for the "ls" command
    _ = subparsers.add_parser("ls", help="List all events.")

    # Create the parser for the "ps" command
    _ = subparsers.add_parser("ps", help="Show the currently running event.")

    # Create the parser for the "add" command
    parser_add = subparsers.add_parser("add", help="Adding a new event.")
    parser_add.add_argument("name", help="Name of the event")
    parser_add.add_argument("-s", "--start", help="Start datetime (default now)")
    parser_add.add_argument("-e", "--end", help="End datetime")

    # Create the parser for the "start" command
    parser_start = subparsers.add_parser("start", help="Starting a new event.")
    parser_start.add_argument("name", help="Name of the event")

    # Create the parser for the "end" command
    _ = subparsers.add_parser("end", help="Ending the current event.")

    return parser


if __name__ == "__main__":
    parser = create_parser()
    args = parser.parse_args()

    ds = DataStore("data.json")

    if args.command == "ls":
        print(convert_to_table(ds.get_all_time_slots()))

    elif args.command == "start":
        time_slots = ds.get_all_time_slots()
        running = list(filter(lambda x: x.end is None, time_slots))
        if len(running):
            print("An event is already running.")
        else:
            ds.add_time_slot(TimeSlot(args.name))
            print(f"Started event {args.name}.")

    elif args.command == "end":
        time_slots = ds.get_all_time_slots()
        running = list(filter(lambda x: x.end is None, time_slots))
        if len(running) <= 0:
            print("No running event.")
        elif len(running) > 1:
            raise Exception("Found multiple running event.")
        else:
            running[0].end_now()
            ds.write_update()
            print(f"Ended event {running[0].name}.")

    elif args.command == "ps":
        time_slots = ds.get_all_time_slots()
        running = list(filter(lambda x: x.end is None, time_slots))
        print(convert_to_table(running))

    elif args.command == "add":
        time_slots = ds.get_all_time_slots()
        running = list(filter(lambda x: x.end is None, time_slots))
        if len(running) > 0 and args.end is None:
            print("An event is already running.")
        else:
            ts = TimeSlot(args.name)
            if args.start is not None:
                ts.start = datetime.strptime(args.start, '%d.%m.%y %H:%M')
            if args.end is not None:
                ts.end = datetime.strptime(args.end, '%d.%m.%y %H:%M')
            ds.add_time_slot(ts)
            ds.write_update()
            print("The event was added.")