#! /usr/bin/python3
from __future__ import unicode_literals
import youtube_dl
import csv

class CSV_Downloader():
	def __init__(self, filename):
		self.filename = filename

	def get_videos(self):
		videos = []
		with open(self.filename, newline='') as csvfile:
			reader = csv.reader(csvfile, delimiter=' ', quotechar='|')
			for row in reader:
				for col in row:
					videos.append(col)
		videos = filter(None, list(set(videos)))
		return videos

	def save_file(self, videos):
		with open(self.filename, 'w', newline='') as csvfile:
			writer = csv.writer(csvfile, delimiter=' ', quotechar='|')
			for video in videos:
				writer.writerow([video])

	def get_first_item(self, videos):
		return next(iter(videos or []), None)

	def start(self):
		ydl_opts = {}
		with youtube_dl.YoutubeDL(ydl_opts) as ydl:
			while True:
				videos = self.get_videos() # getting list of all videos from file
				print('{} videos to go'.format(len(videos))) # print no. of video remaining
				video = self.get_first_item(videos) # get next video for downloading
				if video is None: # check if video is there or not
					break

				ydl.download([video]) # downloading video
				videos.remove(video) # remove video from list
				self.save_file(videos) # save updated list to file

		print('All downloaded')

def main():
	handler = CSV_Downloader('download.csv')
	handler.start()

if __name__ == '__main__':
	main()