import pymongo

from pprint import pprint

from pymongo import MongoClient

# other functions

def print_film_info(film):
    print('Name: ' + film['name'])
    print('Category: ' + film['category'])
    print("\n")

def get_avg_rating(name):
    count = 0
    avg_rating = 0.0
    for review in db.reviews.find({'film_name': name}):
        avg_rating += float(review['rating'])
        count = count + 1
    if count == 0:
        return None
    else:
        return avg_rating / count

# DB functions

def add_film(name, category):
    if db.films.find({'name': name}).count() > 0:
        raise ValueError('Film already in database!')
    db.films.save( { 'name': name, 'category': category, 'actors': []} )

def clear():
    result = db.films.delete_many({})
    print ('Removed ' + str(result.deleted_count) + ' films')

def show_films(category):
    if category == 'all':
        for film in db.films.find():
            print_film_info(film)
    else:
        for film in db.films.find({'category': category}):
            print_film_info(film)

def show_film_info(name):
    if db.films.find({'name': name}).count() == 0:
        raise ValueError('No such film in database!')
    film = db.films.find_one({'name': name})
    print('Name: ' + film['name'])
    print('Category: ' + film['category'])
    print('Rating: ' + str(get_avg_rating(name)))
    print 'Actors: ',
    for actor in film['actors']:
        print actor['name'],
    print("\n")

def add_review(film_name, rating, text):
    if db.films.find({'name': film_name}).count() == 0:
        raise ValueError('No such film in database!')
    print('name: ' + film_name)
    print('review: ' + text)
    db.reviews.save( { 'film_name': film_name, 'rating': int(rating), 'text': text} )

def show_reviews(film_name):
    count = 0
    for review in db.reviews.find({'film_name': film_name}):
        count = count + 1
        print('Review ' + str(count) + ":")
        print('    Rating: ' + str(review['rating']))
        print('    Review: ' + review['text'])
        print("\n")
    if count == 0:
        print('None')

def add_actor(actor_name, film_name):
    if db.films.find({'name': film_name}).count() == 0:
        raise ValueError('No such film in database!')
    actor = {'name': actor_name}
    db.films.update( {"name": film_name}, {"$push": {'actors': actor}}, upsert=False, multi=True)

def show_actor_films(actor_name):
    print("Actor " + actor_name + " was in the following films:")
    count = 0
    for film in db.films.find({"actors.name": actor_name}):
        count = count + 1
        print(film['name'])
    if count == 0:
        print('None')

def change_film_name(old_name, new_name):
    if db.films.find({'name': old_name}).count() == 0:
        raise ValueError('No such film in database!')
    db.films.update({"name": old_name}, {"$set": {'name': new_name}}, upsert=False)

def change_film_category(name, new_category):
    if db.films.find({'name': name}).count() == 0:
        raise ValueError('No such film in database!')
    db.films.update({"name": name}, {"$set": {'category': new_category}}, upsert=False)

# parse commands functions

def get_command_name(full_command):
    parsed_command = full_command.split(" ")
    return parsed_command[0]

def process_command(command_name, full_command):
    parsed_command = full_command.split(" ")
    if command_name == 'add_film':
        name = parsed_command[1]
        category = parsed_command[2]
        add_film(name, category)
    elif command_name == 'show_films':
        category = parsed_command[1]
        show_films(category)
    elif command_name == 'show_film_info':
        name = parsed_command[1]
        show_film_info(name)
    elif command_name == 'add_review':
        film_name = parsed_command[1]
        rating = parsed_command[2]
        text = ""
        for i in range (3, len(parsed_command)):
            text += (' ' + parsed_command[i])
        add_review(film_name, rating, text)
    elif command_name == 'show_reviews':
        film_name = parsed_command[1]
        show_reviews(film_name)
    elif command_name == 'show_actor_films':
        actor_name = parsed_command[1]
        show_actor_films(actor_name)
    elif command_name == 'add_actor':
        actor_name = parsed_command[1]
        film_name = parsed_command[2]
        add_actor(actor_name, film_name)
    elif command_name == 'change_film_name':
        old_name = parsed_command[1]
        new_name = parsed_command[2]
        change_film_name(old_name, new_name)
    elif command_name == 'change_film_category':
        name = parsed_command[1]
        new_category = parsed_command[2]
        change_film_category(name, new_category)
    elif command_name == 'clear':
        clear()
    else:
        print('Invalid command!')

# main program text
client = MongoClient()
command = 'empty'
db = client.film_database

while command != 'exit':
    command = raw_input(" $: ")
    command_name = get_command_name(command)
    try:
        process_command(command_name, command)
    except IndexError:
        print 'Not enough command parameters!'
    except Exception as error:
        print('error: ' + repr(error))
    print("\n");

print('See you around!')