import os
import sys
import csv
from math import ceil
import subprocess
import random
from util import *

import click

@click.command()
@click.option('--count', '-c', default=2, help='Number of subdivisions.')
@click.option('--has_keys/--no_keys', '-k', default=False, help='Whether to split off the keys.')
@click.option('--shuffle/--no_shuffle', default=False, help='Whether to shuffle.')
@click.argument('filename')
def split_csv(count, has_keys, shuffle, filename):
  """Split a CSV into groups."""
  with open(filename, 'r') as f:
    reader = csv.reader(f)
    lines = list(unfussy_reader(reader))
    if has_keys:
      keys = lines[0]
      lines = lines[1:]
    else:
      keys = None

    fn, ext = os.path.splitext(filename)
    if shuffle:
      random.shuffle(lines)
    n = max(1, ceil(len(lines) / count))
    for index in range(count):
      m = index * n
      chunk = lines[m:m+n]
      print(chunk[0])
      out_fn = fn + '-' + str(index+1) + ext
      write_csv(out_fn, keys, chunk)

# Write a CSV
def write_csv(fn, keys, chunk):
  print(fn)
  with open(fn, 'w') as f:
    writer = csv.writer(f)
    if keys is not None:
      writer.writerow(keys)
    for row in chunk:
      writer.writerow(row)


if __name__ == '__main__':
  split_csv()