# 1. create a file called "friends.csv"
# 2. gather the following information 5 friends:
#       name
#       email address
#       favorite cartoon (or movie)
#    for each friend, record the information in one line in friends.csv,
#    separate each piece of information with a comma (,)
# 3. write a function to read the file
#       using open() and read()
# 4. write a function to read the file
#       using open() and readlines()
# 5. write a function to read the file
#       using open() and readline()
# 6. write a function to read the file
#       using with open()
# 7. write a function to read the file and
#    process the information
#       split the information into pieces (reminder, we have csv, thus split by a comma)
#       store the information in a dictionary, where
#          key is (friend) name
#          value is list containing email and cartoon, that is, [email, cartoon]
#    the function then returns the newly created dictionary


file_name = 'friends.csv'



def read_from_file(filename):
    infile = open(filename, 'r')    # default mode: r

    # read the files's contents
    file_contents = infile.read()

    print(file_contents)
    infile.close()

print("==== example: using read() ==== ")
read_from_file(file_name)


def readlines_from_file(filename):
    infile = open(filename, 'r')

    # read the files's contents
    file_contents = infile.readlines()

    print(file_contents)
    infile.close()

print("==== example: using readlines() ==== ")
read_from_file(file_name)


def readline_from_file(filename):
    infile = open(filename, 'r')

    # read the first line
    line = infile.readline()

    # while there are more lines to read
    while line != "":
        print(line.rstrip())   # throws extra spaces at the end and print line
        line = infile.readline()   # read a line

    infile.close()

print("==== example: using readline() ==== ")
readline_from_file(file_name)


def read_file_with_open(filename):
    with open(filename) as infile:
        file_contents = infile.read()

    print(file_contents)

print("==== example: using with open to open the file ==== ")
read_file_with_open(file_name)


def process_info(filename):
    friends_dict = {}

    infile = open(filename, 'r')

    # read the first line
    line = infile.readline().strip()

    # while there are more lines to read
    while line != "":
        pieces = line.split(',')
        if len(pieces) > 0:
            name = pieces[0]
            email = pieces[1]
            cartoon = pieces[2]
            friends_dict[name] = [email, cartoon]

        line = infile.readline().strip()  # read a line

    infile.close()
    return friends_dict

print("==== example: process info ==== ")
print(process_info(file_name))