Anteater B and B

ICS 31 • DAVID G. KAY • UC IRVINE • SPRING 2017

Anteater Bed and Breakfast

Assignment summary: You will write a program to keep track of reservations at "AntBnB", a small "bed and breakfast" hotel.

This assignment is divided into five stages. Each succeeding stage is built upon what you have already written for the previous stage. We expect you to design, write, and test this program according to these stages—first get the first-stage program working, then modify it to satisfy the second stage, and so on. As always, be sure to keep a copy of each completed stage. That way, if you decide you've gotten off on the wrong track for a stage, you can start again easily from the end of the previous stage, without the painstaking task of removing each addition. You should make sure that each stage is entirely correct and working perfectly before you go on to the next. As you complete each stage, you should demonstrate briefly to your TA or tutor that it works correctly before you go on to the following stage. The code you turn in will be the last stage you completed correctly.

Development by stages is good software engineering practice. It is far better to have a program that is correct but incomplete (i.e., it doesn't implement all the features but what it does implement is correct) than one that contains bugs. Grading for this assignment will reflect this, too; it will hurt your score much more to turn in buggy code than not to reach some of the later stages. Let's say that again: Your score will be higher if you do the first three stages correctly than if you do all five with some bugs in the last stages.

What to turn in: On Checkmate, a single Python file containing your last-stage code. You must name your file BandBX.py, where X is one of I, II, III, IV, or V, indicating which stage your code completes correctly, without bugs.

Grading: Your grade depends on organized development (did you design and debug each stage in sequence), completeness (does your program do everything the specification requires), correctness (does it produce the correct results), quality and clarity of your output, good modular design (i.e., organization into functions), good data organization (using data structures appropriately), and good programming style (are your identifier names descriptive, is your organization clear). You will receive appropriate partial credit for each stage you complete correctly. You will receive no credit for work on a later stage if the previous stages are incomplete or incorrect. The whole point of incremental development (i.e., stages) is to kee a programmer from biting off more than he or she can chew.

Finally, have a sense of proportion: Don't knock yourselves out to finish every stage. Many students do, but many students get high grades by turning in a correct version that doesn't complete all the stages. And every quarter, a few students turn in code they copied from someone other than their partner; that's a very sorry situation. The lab assignments count for 30% of your grade. That's 3% for each of 10 assignments. Let's say this BandB problem is half of Lab 9; that makes it worth 1.5%. And turning in something that works correctly for an earlier stage might get you at least 50% credit. So between that and a perfectly complete program is only about 0.75% of the course, or 3/4 of a point out of 100. You'll learn more by doing more, but you can also finish it over the break to keep your skills sharp for ICS 32.

Statement of the problem: UCI has just started a program in hotel and restaurant management; its dean has established a small "bed and breakfast" hotel as a lab for the program's students. The dean has asked you to write the reservations software for this new inn, which will be called the Anteater BandB.

Your program will keep track of the rooms available for rent (these vary, since sometimes a room is closed for redecoration) and the reservations that guests have made for these rooms.

When the full Anteater BandB system is completed, it might have a graphical user interface, but for now your program will be a batch program; this means that you will supply one input file that contains all the commands and one output file that will contain allyour output. Include these two lines in your code:

infile = open('BBcommands.txt', 'r')
outfile = open('BBresults.txt', 'w')

The automated checking depends on your using precisely those file names.

You could easily convert this program to an interactive one with a fancy user interface, where the program presents the user with a menu of commands, accepts the user's selection, prompts the user for whatever additional information the command requires, and then displays the results of that command. We made this assignment a batch program for three reasons: First, it's extra work for you to write the menu-printing and input-prompting commands, some of which you have already done in other assignments. It's easier simply to assume that the data appears in the correct format in the input files. Second, it gives you more practice reading data from external text files. Third, testing your program will be much easier when you can create files of test data rather than typing in each test interactively every time.

The input for this program comes from a single text file named

BBcommands.txt, which consists of an unlimited number of input command lines. We will describe the various commands below; for each stage, you will implement (or modify) a few more commands.

Stage I: For this stage, your program will keep track of the rooms that are available. This stage implements four commands, as described below. On each command line, the first two non-whitespace characters are the command; command letters may be upper or lower case.

NB: (for "add a new bedroom") followed by an integer room number (in the range 1–999). Add a new bedroom with the specified room number.
LB: (for "list bedrooms"). Print a list of the bedrooms currently available. The input file may contain any number of these commands in any order; each LB command prints a list of available bedrooms based on what has been added as of that point. See the sample output below for the format of the printed bedroom list. For this stage, it doesn't matter what order the bedrooms appear in.
PL: (for "print line"), followed by any text. Simply print (or "echo") a line, copying the input (not counting the PL and leading whitespace) to the output. You'll find it useful in testing, and it's also a simple way to make the program's reports clearer or fancier.
**: Comment, followed by any text. Like comments in a program, comment lines don't have any effect on the program's behavior; they just serve as annotations in the command file.

Below is a sample input file for this stage.

** This is a sample command file for the Anteater BandB, Stage I
PL ***********************************************************
PL Here is a list of available bedrooms (before adding any!)
** A well-written program works gracefully with empty lists.
LB
PL ***********************************************************
** Now let's add a bedroom:
NB 101
LB
** And some more:
NB 104
** Extra blanks around the command should be ignored
Nb    102
    NB 201
    Nb      203
 LB
PL Thank you for using the Anteater BandB Reservation System!
** That's the end of the sample data for Stage I.

From this input file, your program should produce the following output:

***********************************************************
Here is a list of available bedrooms (before adding any!)
Number of bedrooms in service:  0
------------------------------------
***********************************************************
Number of bedrooms in service:  1
------------------------------------
101
Number of bedrooms in service:  5
------------------------------------
101
104
102
201
203
Thank you for using the Anteater BandB Reservation System!

One of the early questions to ask when designing a program is what data structure(s) you should use to represent the main information in the program. Making decisions like this becomes easier with practice, but there are two things to keep in mind. First, start with the simplest data structure that does the job. (For the collection of bedrooms in this stage, maybe a list of integer room numbers is good enough, or maybe a set of room numbers.) Second, accept that your first choice may not be your final choice; as the specifications become clearer or as circumstances change (or as you get to later stages in a problem like this one), you may decide that something else would work better. This kind of revision is a normal part of programming. It's no tragedy to rewrite some code in a better way, just as you should expect to revise natural-language documents. (For the bedrooms in this problem, we might decide to use a dictionary whose key is the room number and whose value is a namedtuple of room information. But we shouldn't necessarily jump to this arrangement until we're sure it helps us.)

Stage II: Each stage of this assignment will continue to handle all the commands of the previous stages, of course. For this stage, your program will handle deletions from the list of available bedrooms.

DB: (for "delete bedroom"), followed by a bedroom number. Delete the specified room from the list. Print an error message if the specified room isn't on the list.

Here is some sample input for this stage:

** This is a sample command file for the Anteater BandB, Stage II
** First, add some bedrooms:
NB 301
nb 302
NB 303
** Now list what we have:
PL First list of available bedrooms:
LB
** Next, delete one:
DB 302
** And show the list reflecting the deletion:
PL List of available bedrooms after deleting one:
LB
** Try to delete a bedroom that doesn't exist, and get an error message.
DB 405
** Now add some more:
NB 302
NB 304
NB 305
PL List of available bedrooms:
LB
** We delete a bedroom ...
db   301
** ... we add another to the list.
NB 307
PL Another list, having deleted one and added another:
LB
PL Thank you for choosing the Anteater BandB Reservation System!
** That's the end of the sample data for Stage II.

For the above input, your program should produce the following output:

First list of available bedrooms:
Number of bedrooms in service:  3
------------------------------------
301
302
303
List of available bedrooms after deleting one:
Number of bedrooms in service:  2
------------------------------------
301
303
Sorry, can't delete room 405; it is not in service now
List of available bedrooms:
Number of bedrooms in service:  5
------------------------------------
304
305
301
302
303
Another list, having deleted one and added another:
Number of bedrooms in service:  5
------------------------------------
302
303
304
305
307
Thank you for choosing the Anteater BandB Reservation System!

Stage III: For this stage, your program will keep track of reservations for specific rooms on specific dates. The first new command for this stage adds a reservation:

RR: (for "reserve room") followed by a bedroom number, then an arrival date in the form mm/dd/yyyy, then a departure date in the form mm/dd/yyyy, then the guest's name): Add a new reservation for the specified room on the specified dates.

Your program will keep track of all the reservations. An attempt to reserve a room that isn't on the list of available rooms should produce an error message. (Note that "available" means the same thing here that it has in the previous stages: Any room that is "in service," whether reserved by a guest or not, is "available." At this stage your program is not checking for occupied or free rooms.)

At this stage, your program does not have to perform any checking that the dates are valid, nor does it have to identify conflicting reservations. Each new reservation prints and saves a unique "confirmation number" so the user can refer to it later (to cancel it, for example); this confirmation number should just be 1 for the first reservation added, 2 for the next, and so on, always increasing.

To make your coding task easier, import the Python library datetime and use it for date calculations. It's harder than you might think to get calculations about dates (e.g., how many days from date A to date B?) correct. The library will do it for you at the low cost of reading the documentation to see how it works. The split function with a "/" argument will be helpful, too.

Also handle these commands:

LR: (for "list reservations"). Print all the reservations.
DR: (for "delete reservation"), followed by the confirmation number of a reservation. Deletes the specified reservation. If a DR command gives a confirmation number that isn't in the list of reservations, your program should produce an error message.

Here is some sample input for this stage. [It's a common temptation to use an elaborate test case like this one as the first test of your newly modified program. It's all right to indulge that temptation once, if you must; of course, your test will fail. Newly modified programs always have bugs. At that point, however, you should try a succession of smaller, more circumscribed tests, rather than ramming this same large test through the program over and over again until you finally force it through successfully. It's more productive, more thorough, and better organized in the long run to test each feature separately before going on to complex combinations. By the same token, however, adequate testing involves more than this single combination test case; this one case does not test everything that needs testing for this stage.]

** This is a sample command file for the Anteater BandB, Stage III
** First, add some bedrooms:
NB 301
NB 302
nb 303
** Now make some reservations
RR 303 10/17/2012 10/19/2012 Conrad Hilton
RR 303 12/31/2012   1/2/2013 Cesar Ritz
RR 301 11/3/2012  12/15/2017 Leona Helmsley
RR 777 1/1/2012     1/2/2012 Ian Schrager
LR
** Next, delete one:
DR 2
** And show the list reflecting the deletion:
PL List of reservations after deleting one:
LR
** Now try to delete that one again (which should give an error):
DR 2
** Now add another two reservations:
RR 302 1/1/2013  2/15/2013 Howard Johnson
RR 303 11/25/2012 11/30/2012 Sultan of Brunei
** And try two more bogus deletions:
DR 2
DR 17
** Finally, list the remaining reservations:
LR
PL Thank you for perusing the Anteater BandB Reservation System!
** That's the end of the sample data for Stage III.

The sample input above should produce results as shown below:

Reserving room 303 for Conrad Hilton -- Confirmation #1
    (arriving 10/17/2012, departing 10/19/2012)
Reserving room 303 for Cesar Ritz -- Confirmation #2
    (arriving 12/31/2012, departing 1/2/2013)
Reserving room 301 for Leona Helmsley -- Confirmation #3
    (arriving 11/3/2012, departing 12/15/2017)
Sorry; can't reserve room 777; room not in service
Number of reservations:  3
No. Rm. Arrive      Depart     Guest
------------------------------------------------
  1 303 10/17/2012 10/19/2012 Conrad Hilton
  2 303 12/31/2012  1/ 2/2013 Cesar Ritz
  3 301 11/ 3/2012 12/15/2017 Leona Helmsley
List of reservations after deleting one:
Number of reservations:  2
No. Rm. Arrive      Depart     Guest
------------------------------------------------
  1 303 10/17/2012 10/19/2012 Conrad Hilton
  3 301 11/ 3/2012 12/15/2017 Leona Helmsley
Sorry, can't cancel reservation; no confirmation number 2
Reserving room 302 for Howard Johnson -- Confirmation #4
    (arriving 1/1/2013, departing 2/15/2013)
Reserving room 303 for Sultan of Brunei -- Confirmation #5
    (arriving 11/25/2012, departing 11/30/2012)
Sorry, can't cancel reservation; no confirmation number 2
Sorry, can't cancel reservation; no confirmation number 17
Number of reservations:  4
No. Rm. Arrive      Depart     Guest
------------------------------------------------
  1 303 10/17/2012 10/19/2012 Conrad Hilton
  3 301 11/ 3/2012 12/15/2017 Leona Helmsley
  4 302  1/ 1/2013  2/15/2013 Howard Johnson
  5 303 11/25/2012 11/30/2012 Sultan of Brunei
Thank you for perusing the Anteater BandB Reservation System!

Stage IV: In this stage, your program will check each command for various inconsistencies and impossible situations.

First, your program should reject any reservation whose arrival date is later than the departure date, or any reservation where the guest arrives and departs on the same day (we're running a respectable establishment). [Check the documentation for the datetime library for functions that help you with this.]

Your program must also check each reservation for a given bedroom for conflicts with any existing reservations for that bedroom; you can't rent the same room to two different guests on the same night. (Note, however, that one reservation can have the same arrival date as another reservation's departure date, since the departure date is the date the guest leaves, so the room is vacant that night.)

Next, your program should print an error message if the user attempts to add a bedroom with the same number as one that is already on the list.

Finally, if the user deletes a bedroom, your program should cancel all the reservations for that bedroom (printing an appropriate message for each cancellation).

Here is some sample input for this stage:

** This is a sample command file for the Anteater BandB, Stage IV
** First, add some bedrooms:
NB 101
NB 102
NB 103
** Now make some reservations:
RR 101 12/17/2012 12/19/2012 Claude Crillon
RR 102 12/31/2012  1/5/2013 Donald Dorchester
** Try a few reservations that go backwards in time:
RR 103 11/3/2012 12/15/1989 Bonnie Bonaventure
RR 103 12/17/2012 11/18/2012 Osamu Okura
RR 103 12/31/2012 12/25/2012 Penelope Peninsula
** And one that comes and goes on the same date:
RR 103 12/1/2012 12/1/2012 Randolph Raffles
LR
** Now try some conflicting reservations
** One that overlaps exactly:
rr 101 12/17/2012 12/19/2012 George Cinq
** One that overlaps a couple of days:
rr 102 12/25/2012  1/1/2013 Renata Rossiya
** One that's completely contained:
rr 102 1/1/2013 1/3/2013 Mark Hopkins
** And one that doesn't conflict, barely:
rr 102 12/25/2012 12/31/2012 Belle Air
LR
** Now try to add an already-existing bedroom:
NB 103
** Finally, delete a bedroom (which cancels all its reservations):
db 102
rr 103 12/17/2012 12/19/2012 Alfreda Algonquin
PL The final list of reservations:
LR
PL Thank you for confusing the Anteater BandB Reservation System!
** That's the end of the sample data for Stage IV.

The sample input above should produce results as shown below:


Reserving room 101 for Claude Crillon -- Confirmation #1
    (arriving 12/17/2012, departing 12/19/2012)
Reserving room 102 for Donald Dorchester -- Confirmation #2
    (arriving 12/31/2012, departing 1/5/2013)
Sorry, can't reserve room 103 (11/3/2012 to 12/15/1989);
    can't leave before you arrive.
Sorry, can't reserve room 103 (12/17/2012 to 11/18/2012);
    can't leave before you arrive.
Sorry, can't reserve room 103 (12/31/2012 to 12/25/2012);
    can't leave before you arrive.
Sorry, can't reserve room 103 (12/1/2012 to 12/1/2012);
    can't arrive and leave on the same day.
Number of reservations:  2
No. Rm. Arrive     Depart     Guest
------------------------------------------------
  1 101 12/17/2012 12/19/2012 Claude Crillon
  2 102 12/31/2012  1/ 5/2013 Donald Dorchester
Sorry, can't reserve room 101 (12/17/2012 to 12/19/2012);
   it's already booked (Conf. #1)
Sorry, can't reserve room 102 (12/25/2012 to  1/ 1/2013);
   it's already booked (Conf. #2)
Sorry, can't reserve room 102 ( 1/ 1/2013 to  1/ 3/2013);
   it's already booked (Conf. #2)
Reserving room 102 for Belle Air -- Confirmation #3
    (arriving 12/25/2012, departing 12/31/2012)
Number of reservations:  3
No. Rm. Arrive     Depart     Guest
------------------------------------------------
  1 101 12/17/2012 12/19/2012 Claude Crillon
  2 102 12/31/2012  1/ 5/2013 Donald Dorchester
  3 102 12/25/2012 12/31/2012 Belle Air
Sorry, can't add room 103 again; it's already on the list.
Deleting room 102 forces cancellation of this reservation:
   Donald Dorchester arriving 12/31/2012 and departing  1/ 5/2013 (Conf. #2)
Deleting room 102 forces cancellation of this reservation:
   Belle Air arriving 12/25/2012 and departing 12/31/2012 (Conf. #3)
Reserving room 103 for Alfreda Algonquin -- Confirmation #4
    (arriving 12/17/2012, departing 12/19/2012)
The final list of reservations:
Number of reservations:  2
No. Rm. Arrive     Depart     Guest
------------------------------------------------
  1 101 12/17/2012 12/19/2012 Claude Crillon
  4 103 12/17/2012 12/19/2012 Alfreda Algonquin
Thank you for confusing the Anteater BandB Reservation System!

Stage V: For this stage, your program will produce various information listings.

RB: (for "reservations by bedroom"), followed by a number. Lists all reservations for a given bedroom.
RG: (for "reservations by guest"), followed by a string. List all reservations for a given guest.
LA: (for "list arrivals"), followed by a date in the same mm/dd/yyyy form as before. Print a list of all guests arriving on the specified date.
LD: (for "list departures"), followed by a date in the same mm/dd/yy form as before. Print a list of all guests departing on the specified date.
LF: (for "list free bedrooms"), followed by two dates. List all bedrooms that are free each night for a guest arriving on the first date and departing on the second.
LO: (for "list occupied bedrooms"), followed by two dates. List all bedrooms that are occupied for at least one night between the given arrival and departure dates.

Here is some sample input for this stage:

** This is a sample command file for the Anteater BandB, Stage V
** First, add some bedrooms:
NB 501
NB 502
NB 503
NB 504
** Now make some reservations
RR 503 12/10/2012 12/15/2012 I. Joliet
rr 502  1/10/2013  1/15/2013 I. Joliet
rr 502 12/10/2012 12/14/2012 K. Leavenworth
rr 502 12/10/2013 12/14/2013 K. Leavenworth
rr 504  2/15/2013 12/14/2013 C. S. Quentin
LR
** List reservations for a bedroom
RB 502
** List reservations for two guests
RG K. Leavenworth
RG C. S. Quentin
** List everyone arriving December 10, 2012
LA 12/10/2012
** List everyone (i.e. nobody) arriving December 9
LA 12/9/2012
** List everyone departing December 14, 2013
LD 12/14/2013
** List the free rooms when the hotel is empty
LF 12/20/2012 12/25/2012
** List the free rooms when some are reserved
LF 12/12/2012 12/20/2012
** List the free rooms on a single date
** (Remember that a room isn't occupied on the night of a departure)
LF 12/14/2012 12/14/2012
** List occupied rooms on various dates
LO 12/14/2012 12/14/2012
LO 12/12/2012 12/20/2012
LO 12/20/2012 12/25/2012
PL Thank you for abusing the Anteater BandB Reservation System!
** That's the end of the sample data for Stage V.

The sample input above should produce results as shown below:

Reserving room 503 for I. Joliet -- Confirmation #1
    (arriving 12/10/2012, departing 12/15/2012)
Reserving room 502 for I. Joliet -- Confirmation #2
    (arriving 1/10/2013, departing 1/15/2013)
Reserving room 502 for K. Leavenworth -- Confirmation #3
    (arriving 12/10/2012, departing 12/14/2012)
Reserving room 502 for K. Leavenworth -- Confirmation #4
    (arriving 12/10/2013, departing 12/14/2013)
Reserving room 504 for C. S. Quentin -- Confirmation #5
    (arriving 2/15/2013, departing 12/14/2013)
Number of reservations:  5
No. Rm. Arrive     Depart     Guest
------------------------------------------------
  1 503 12/10/2012 12/15/2012 I. Joliet
  2 502  1/10/2013  1/15/2013 I. Joliet
  3 502 12/10/2012 12/14/2012 K. Leavenworth
  4 502 12/10/2013 12/14/2013 K. Leavenworth
  5 504  2/15/2013 12/14/2013 C. S. Quentin
Reservations for room 502:
    1/10/2013 to  1/15/2013:  I. Joliet
   12/10/2012 to 12/14/2012:  K. Leavenworth
   12/10/2013 to 12/14/2013:  K. Leavenworth
Reservations for K. Leavenworth:
   12/10/2012 to 12/14/2012:  room 502
   12/10/2013 to 12/14/2013:  room 502
Reservations for C. S. Quentin:
    2/15/2013 to 12/14/2013:  room 504
Guests arriving on 12/10/2012:
   K. Leavenworth (room 502)
   I. Joliet (room 503)
Guests arriving on 12/9/2012:
Guests departing on 12/14/2013:
   C. S. Quentin (room 504)
   K. Leavenworth (room 502)
Bedrooms free between 12/20/2012 to 12/25/2012:
   504
   501
   502
   503
Bedrooms free between 12/12/2012 to 12/20/2012:
   504
   501
Bedrooms free between 12/14/2012 to 12/14/2012:
   504
   501
   502
Bedrooms occupied between 12/14/2012 to 12/14/2012:
   503
Bedrooms occupied between 12/12/2012 to 12/20/2012:
   502
   503
Bedrooms occupied between 12/20/2012 to 12/25/2012:
Thank you for abusing the Anteater BandB Reservation System!

Further enhancements: If you had more time, you could extend this program further. The following are not a part of this assignment to be turned in, but they are directions you could pursue independently (e.g., to keep your skills up between now and when you take ICS 32).

Make the LB command print the room list in order by room number and the LR command list the reservations in order by arrival date.
Make the file handling more realistic. In a real hotel, the room reservation system must save the reservation information at the end of the day, to be used as the following day's starting data. Before exiting, your program should write out the room and reservation information to an external file as a series of NB and RR commands, in the same format as the input command file. You should not automatically write the end-of-day data on top of the original input file; prompt the user for a new file name. Thereafter, when your program starts it will prompt the user for the file containing the previous day's ending data and read in those commands before it asks for the current day's command file and handles the commands there. [In fact, there is an inconsistency here, because the RR command doesn't have space for an existing reservation's confirmation number. Thus, any carried-forward reservation will get a new confirmation number, and the number the guest has won't be any good. Propose a solution to this problem (and implement it).]
Before cancelling a reservation, check to see if it can be moved to another room. First check if there's another room free for the entire duration of the reservation, and move it there. If no single room can accommodate the reservation, but if it could be split between two rooms, do that. Only if that's not possible, cancel it.

The following usual warnings, advice, policies, and practices apply to this assignment:

Get started early.
Read and re-read the specifications.
Please don't succumb to the temptation to share code with your classmates other than your lab partner. As you know, we check for potential plagiarism both manually and using automated tools. The consequences of academic dishonesty are far worse than those of completing one fewer stage of an assignment.
Submit all your Python source code via Checkmate in a file named BandBX.py, where X is one of I, II, III, IV, or V, indicating which stage your code completes correctly, without bugs. Each pair should submit just one solution.
Fill out a partner evaluation in the Partner App.

Written by David G. Kay in Winter 2005, based on earlier assignments. Modified by David G. Kay for Python, Winter 2012, and for ICS 31, Wintrer 2013 and Spring 2017.