''' Purpose: continue string manipulation introduction
'''

import pause

print()

# strings can produced strip versions of themselves -- a
# version without LEADING or TRAILING whitespace.  Internal
# whitespace is unaffected.  The ability comes from the string
# member method strip()
# ------------

q = '   There is a door open    to walk through '

print( 'q: \'' + q + '\''  )

### pause to think what has happened
print(); pause.until_ready(); print()

print( '### mis-attempted stripping' )

q.strip()                   # q is unaffected. strip() always produces
                            # a new string
# strip() removes leading and trailing whitespaces from the result of the input(), which we store in the variable q here
# ALWAYS hands back a NEW string; the original is NOT changed !!!!!!!!!!!!
# in this case, q is still the same as before

# split() also hands back a NEW thing, which is a list of things within that string that were separated by spaces


print( 'q.strip()' )

print( 'q: \'' + q + '\''  )

### pause to think what has happened
print(); pause.until_ready(); print()

print( '### stripping' )

s = q.strip()               # q is still unaffected, but s is a
                            # stripped version of q
# we capture the result of the strip() by putting it into the variable s!!
# q is still not changed
# strip() without arguments will remove just the leading and trailing spaces (from q in this case)

print( 's = q.strip()' )
print( 'q: \'' + q + '\''  )
print( 's: \'' + s + '\'' )

### pause to think what has happened
print(); pause.until_ready(); print()

# strings can produce their component words.  The ability comes
# from the string member method split()
#                 -------------

print( '### splitting' )

f = 'bananas  $0.69'
c = 'SEAS CS 1112'

print( 'f: \'' + f + '\'' )
print( 'c: \'' + c + '\'' )

### pause to think what has happened
print(); pause.until_ready(); print()

fruit, price = f.split()              # splits fruit into list of individual
                                      # words, which for this example is a
                                      # fruit and its cost
# we know that f should have two things when it is split on the space
# so we can have two things on the left side

print( 'fruit, price = f.split()' )
print( fruit, 'costs', price, 'per pound' )

### pause to think what has happened
print(); pause.until_ready(); print()

school, subject, number = c.split()   # splits course listing  into list of
                                      # individual words, which for this
                                      # example is a school, subject, and
                                      # course number

print( 'school, subject, number = c.split()' )
print( 'School:', school, '  subject:', subject, '  number:', number )

### pause to think what has happened
print(); pause.until_ready(); print()

# print( '### list making' )
#
# list1 = f.split()              # list1 is a 2-element list
# list2 = c.split()              # list2 is a 3-element list
#
# print( 'list1 = f.split()' )
# print( 'list2 = c.split()' )
#
# print( 'list1: ', list1 )
# print( 'list2: ', list2 )

reply = input( 'Enter some words: ' )
words = reply.split()
# cannot put different number of variables on the left side because we don't know how many words the user is going to type
# words = list of words from the single string reply
print( 'words =', words )
# if we enter 'UFOs are oval', then we split on space --> words = [ 'UFOs', 'are', 'oval' ]
# if you only have one variable on the left side, then what you have is a list of things from the function split()

# to look at individual things in a list, we can do repeat work
# we use looping called a for loop
# starts with keyword for
# followed by a loop variable
# followed by keyword in
# lastly, followed by the name of the list you want to look at
# really lastly, ends with a :

# word is our loop variable (can be named anything) - we chose word because we are going through a list of words
# could have been w or n or h (just make sure it makes sense to you)
# translate: for each word in the list of words, we want to print the word
for word in words:
    print( word )
    # we indent code that you want to be repeated
    # tells python this belongs in the for loop
    # once there's no more code within this block, the for loop starts over until we finish the list

    # if reply = 'how old are you' --> words = ['how', 'old', 'are', 'you']
    # first time, word = 'how'
    # second time, word = 'old'
    # third time, word = 'are'
    # fourth time, word = 'you'
    # since we run out of things, the loop ends

for character in reply:
    print( character )

    # reply is not a list, but it is a string that's still a sequence of characters
    # therefore, the loop variable represents each character in the string reply, not each word like we did above