"""

Author  : flo
date    : 2017.02.16
Purpose : example of finding out the amount of principle paid to mortgage lender per year.
        : This version is special.

Comments: Simulate the number of mortgage payments based on the loan amount
        : one can alter the number of months in the outer loop to reflect the
        : term for your mortgage.
        : run the example command to first see how it needs to run.
        :

example : python mortgage.py -h
"""


import getopt
import sys


def computeMortgage(tot, mon, rate, intr, pal):

    for i in range(1, mon+1):
        # assuming 30 days per-month
        for x in range(1, 31):
            # .0450 is the assume interest amount
            tsum = tot * (rate/100.00) * (1.00/365.00)
            tot = tsum + tot
            print "Month\t" + str(i) + " Day\t" + str(x) + "\t" + str(round(tot, 2)) + "\t" + str(round(tsum, 2))
        tot = tot - (pal + intr)


def version():

    print "version 0.0.3"


def usage():

    usage = """

            usage: python mortgage.py [-l FLOAT_VALUE] [-t Integer_VALUE] [-r FLOAT_VALUE]
                                      [-i FLOAT_VALUE] [-p FLOAT_VALUE] [-h, --help] [-v, --version]

            usage: python mortgage.py

            usage: python mortgage.py -l 250000.99 -t 24 -r 4.95 -i 515.69 -p 600

            usage: python mortgage.py -v

            usage: python mortgage.py -h

            options :
            -l, --loanamt          take a loan Value amount
            -t, --loanterm         take an actual or a hypothetical value term
            -r, --loanrate         take the monthly interests value rate
            -i, --loanint          take the monthly interests value amount
            -p, --loanprin         take the monthly principle value amount
            -v, --version          show program's version number and exit
            -h, --help             show this help message and exit
            """

    print usage


def main():

    # default values
    lamt, lterm, lrate, lint, lprin = 200000.99, 24, 3.89, 450, 600.99

    # try the getopt function for kicks and giggles
    try:
        opts, args = getopt.getopt(sys.argv[1:], 'l:t:r:i:p:v:h', ['loanamt', 'loanterm', 'loanrate', 'loanint', 'loanprin', 'version', 'help'])
    except getopt.GetoptError as err:
        # print something and exit
        print str(err)
        usage()
        sys.exit(2)

    # pull data from getopt
    for o, a in opts:
        if o in ('-l', '--loanamt'):
            lamt = float(a)
        elif o in ('-t', '--loanterm'):
            lterm = int(a)
        elif o in ('-r', '--loanrate'):
            lrate = float(a)
        elif o in ('-i', '--loanint'):
            lint = float(a)
        elif o in ('-p', '--loanprin'):
            lprin = float(a)
        elif o in ('-v', '--version'):
            version()
            sys.exit()
        elif o in ('-h', '--help'):
            usage()
            sys.exit()
        else:
            assert False, "unhandled option"

    # compute and forecast it all
    computeMortgage(lamt, lterm, lrate, lint, lprin)

# calling main
if __name__ == "__main__":
    main()