import praw
import time
import os


def bot_start():
    r = praw.Reddit(username = ''
				password = ''
				client_id = '',
				client_secret = '',
				user_agent = "")

    return r

def bot_run(r, comments_replied_to):

    subreddit = r.subreddit('subredditname')
    for comment in subreddit.comments(limit=2):

        if 'keyword' in comment.body and comment.id not in comments_replied_to and comment.author != r.user.me():
            print ("String found: " + comment.id)
            print(20*"-")
            print ("Author: ", comment.author)
            print(20*"-")
            comment.reply("reply")
            print ("Replied to: " + comment.id)
            print(20*"-")

            comments_replied_to.append(comment.id)

            with open ("comments_replied_to.txt", "a") as f:
                f.write(comment.id + "\n")

    print ("Search complete")

    print ("waiting...")
    time.sleep(10)

def get_saved_comments():
    if not os.path.isfile("comments_replied_to.txt"):
        comments_replied_to = []
    else:
        with open("comments_replied_to.txt", "r") as f:
            comments_replied_to = f.read()
            comments_replied_to = list(comments_replied_to)
            comments_replied_to = list(filter(None, comments_replied_to))

    return comments_replied_to

r = bot_start()
comments_replied_to = get_saved_comments()


while True:
    bot_run(r, comments_replied_to)