#! /usr/bin/perl

require "cgi-lib.pl";
require "cl-lib.pl";



sub getPMIRate{
 if (@_[0] == "fixed"){
  if (@_[1] > 0.9){
   return 0.005;
  } elsif (@_[1] > 0.85){
   return 0.0035;
  } else {
   return 0.003;
  }
 } else {
  if (@_[1] > 0.9) {
   return 0.0055;
 } elsif (@_[1] > 0.85) {
   return 0.0045;
  } else {
   return 0.0035;
  }
 }
}


sub RentvsBuy {
local( $intratevar, $loantermvar, $numholdingyrsvar, $monthsheldvar, $downpaymentvar, $housepricevar, $loanamountvar, $rentalincomevar, $condoduesvar, $count, $renterscostvar);
local( $proptaxvar, $insurancevar, $repairsvar, $closcostsvar, $taxsvgsvar, $oppcostvar, $remtincvar, $bcondoduesvar, $amortvar, $appvar, $pivar, $yearprinintvar);

    if ( $input{purchaseprice} == 0) {
        print "<p>You must enter a purchase price in order to perform an analysis.</p>\n";
        return 0;
    } else {
        $housepricevar = $input{purchaseprice};
    }

    if ( $input{loanamount} > $housepricevar) {
        print "<p>Loan amount cannot exceed purchase price.</p>\n";
        return 0;
    } else {
        $loanamountvar = $input{loanamount};
    }

    $rentalincomevar = $input{rentalincome};
    $condoduesvar = $input{condodues};

    if ( $input{interestrate} > 0.20 ) {
      print "<p>Interest rate should not be over 20%.</p>\n";
      return 0;
    } else {
     $intratevar = $input{interestrate};
    }
    if ( $input{loanterm} > 30 ) {
     print "<p>A loan term greater than 30 years is unrealistic.</p>\n";
     return 0;
    } else {
    $loantermvar = $input{loanterm} * 12;
    }

    $downpaymentvar = $housepricevar - $loanamountvar;
    $pifactor = (($intratevar / 12) / (1 - (1 / (1 + ($intratevar / 12)) ** $loantermvar)));
    $pivar = $loanamountvar * $pifactor;

    if ($input{rent} < 1) {
     print "<p>Rent should be greater than 1$.</p>\n";
     return 0;
    }
    $renterscostvar = $input{rent} + $input{rentersinsurance} + $input{rentersrepairs} + $input{renterscarport} + $input{rentersofees} + $input{rentershaf};

    if ( ($input{flow} eq "firstmonth")) {

        $principalinterest = $pivar;
        $buyers{propertytax} = $housepricevar * $input{propertytax} / 12;
        $buyers{insurance} = $housepricevar * $input{hazins} / 12;
        $buyers{repairs} = $housepricevar / 1200;
        $buyers{closingcosts} = 0;
        $buyers{taxsavings} = -1 * $input{incometax} * ($loanamountvar * $intratevar + $housepricevar * $input{propertytax}) / 12;
        $buyers{opportunitycost} = (1 - $input{incometax}) * $input{returnoninvestment} * $downpaymentvar / 12;
        $buyers{rentalincome} = ($input{incometax} - 1) * $rentalincomevar;
        $buyers{condodues} = $condoduesvar;
        $buyers{amortization} = 0;
        $buyers{appreciation} = 0;

        $renters{realmonthlycost} = $renterscostvar;
        $buyers{realmonthlycost} = $pivar + $buyers{propertytax} + $buyers{insurance} + $buyers{repairs} + $buyers{taxsavings} + $buyers{opportunitycost} + $buyers{rentalincome};

    } else {
        $numholdingyrsvar = $input{timetohold};
        $monthsheldvar = 12 * $numholdingyrsvar;

        $yearprinintvar = 12 * $pivar;

        $rvb{rentcost, 0} = 0;
        $rvb{pri, 0} = 0;
        $rvb{intr, 0} = 0;
        $rvb{loanamt, 0} = $loanamountvar;
        $closcostsvar = ($input{points} * $loanamountvar) + ($input{closcosts} * $housepricevar);
        $taxsvgsvar = -1 * $input{incometax} * $input{points} * $loanamountvar;
        $rvb{buycost, 0} = $closcostsvar;
        $count = 1;

        while ($count <= $numholdingyrsvar) {
            if ( ($loanamountvar > (0.8 * $housepricevar))) {
                $closcostsvar += ($loanamountvar * &getPMIRate("fixed", ($loanamountvar / $housepricevar)));
            }
            $housepricevar = (1 + $input{appreciation}) * $housepricevar;
            $proptaxvar += ($housepricevar * $input{propertytax});
            $insurancevar += ($housepricevar * $input{hazins});
            $repairsvar += ($housepricevar / 100);
            if ( $count <= ($loantermvar / 12)) {
             $rvb{pri, $count} = ($yearprinintvar )- (($intratevar * $loanamountvar) );
             $rvb{intr, $count} = ($intratevar * $loanamountvar);
             $loanamountvar = (1 + $intratevar) * $loanamountvar - $yearprinintvar;
             $rvb{loanamt, $count} = $loanamountvar;
            } else {
             $loanamountvar = 0;
             $yearprinintvar = 0;
             $rvb{pri, $count} = 0;
             $rvp{intr, $count} = 0;
             $rvb{loanamt, $count} = 0;
            }
            $taxsvgsvar += (-1 * $input{incometax} * ($intratevar * $loanamountvar + ($housepricevar * $input{propertytax})));
            $oppcostvar += ((1 - $input{incometax}) * $input{returnoninvestment} * $downpaymentvar);
            $remtincvar += (-12 * (1 - $input{incometax}) * $rentalincomevar);
            # used to be a monthly V
            $bcondoduesvar += $condoduesvar;
            if ( ($input{flow} eq "cashflow")) {
             $amortvar = 0;
             $appvar = 0;
            } else {
             $amortvar +=  (-1 * ($yearprinintvar - ($intratevar * $loanamountvar)));
             $appvar +=  (-1 * $housepricevar * $input{appreciation});
            }
            $rvb{buycost, $count} = ($count <= ($loantermvar / 12))?
             ($count * $yearprinintvar + $proptaxvar + $insurancevar + $repairsvar + $closcostsvar + $taxsvgsvar + $oppcostvar + $remtincvar + $bcondoduesvar + $amortvar + $appvar):
             ($loantermvar * $pivar + $proptaxvar + $insurancevar + $repairsvar + $closcostsvar + $taxsvgsvar + $oppcostvar + $remtincvar + $bcondoduesvar + $amortvar + $appvar);
            $rvb{rentcost, $count} = $rvb{rentcost, $count - 1} + (12 * $renterscostvar);

        $count++;
        }

        if ( $count <= ($loantermvar / 12)) {
            $principalinterest = $pivar;
        } else {
            $principalinterest = $pivar * $loantermvar / $monthsheldvar;
        }

        $buyers{propertytax} = $proptaxvar / $monthsheldvar;
        $buyers{insurance} = $insurancevar / $monthsheldvar;
        $buyers{repairs} = $repairsvar / $monthsheldvar;
        $buyers{closingcosts} = $closcostsvar / $monthsheldvar;
        $buyers{taxsavings} = $taxsvgsvar / $monthsheldvar;
        $buyers{opportunitycost} = $oppcostvar / $monthsheldvar;
        $buyers{rentalincome} = $remtincvar / $monthsheldvar;
        $buyers{condodues} = $bcondoduesvar / $monthsheldvar;
        $buyers{amortization} = $amortvar / $monthsheldvar;
        $buyers{appreciation} = $appvar / $monthsheldvar;

        $renters{realmonthlycost} = ($rvb{rentcost, $numholdingyrsvar} / $monthsheldvar);
        $buyers{realmonthlycost} = ($rvb{buycost, $numholdingyrsvar} / $monthsheldvar);


    }

}

sub dumpinfo {

printf(  <<endDump,$principalinterest,$buyers{propertytax},$buyers{insurance},$buyers{repairs},$buyers{closingcosts},$buyers{taxsavings},$buyers{opportunitycost},$buyers{rentalincome},$buyers{condodues},$buyers{amortization},$buyers{appreciation},$buyers{realmonthlycost},$renters{realmonthlycost},$principalinterest,$rvb{buycost,0}+$rvb{loanamt,0},$rvb{rentcost,$input{timetohold}});

<table align="center" width="90%" border=1><tr><td colspan="6" class="HeaderTD"><b>After Tax Monthly Costs</b></td></tr>
<tr><td class="HeaderTDHL">Principal Interest  </td><td align="right">\$%9.2f</td><td class="HeaderTDHL">Closing Costs       </td><td align="right">\$%9.2f</td> <td class="HeaderTDHL">Condo Dues          </td><td align="right">\$%9.2f</td></tr>
<tr><td class="HeaderTDHL">Property Tax        </td><td align="right">\$%9.2f</td><td class="HeaderTDHL">Tax Savings         </td><td align="right">\$%9.2f</td> <td class="HeaderTDHL">Amortization       </td><td align="right">\$%9.2f</td></tr>
<tr><td class="HeaderTDHL">Insurance          </td><td align="right">\$%9.2f</td><td class="HeaderTDHL">Opportunity Cost    </td><td align="right">\$%9.2f</td> <td class="HeaderTDHL">Appreciation       </td><td align="right">\$%9.2f</td></tr>
<tr><td class="HeaderTDHL">Repairs            </td><td align="right">\$%9.2f</td><td class="HeaderTDHL">Rental Income       </td><td align="right">\$%9.2f</td> </tr>
</table>
<table width="90%" border=1 align="center" nowrap>
<tr><td class="HeaderTD" valign="top" width="60%" class="HeaderTD">&nbsp;</td><td class="HeaderTD" align="centeR" width="20%"><b>Buying</b></td><td class="HeaderTD" align="centeR" width="20%"><b>Renting</b></td></tr>
<tr><td class="HeaderTDHL" valign="top">Monthly Payment</td><td align="right">\$%9.2f</td><td align="right">\$%9.2f</td></tr>
<tr><td class="HeaderTDHL" valign="top">Monthly Interest</td><td align="right">\$%9.2f</td><td align="right">\$0.00</td></tr>
<tr><td class="HeaderTDHL" valign="top">Total Cost if Paid Today</td><td align="right" valign="bottom">\$%9.2f</td><td align="right" valign="bottom">\$%9.2f</td></tr>
</table>
endDump

 if ($input{form} ne "firstmonth") {
  print "<table border=1 align='center' width='90%'>";
  print "<tr><td class='HeaderTD'>Yr.</td><td class='HeaderTD'>Principal</td><td class='HeaderTD'>Interest</td><td class='HeaderTD'>Loan Amount</td><td class='HeaderTD'>Buying Cost</td><td class='HeaderTD'>Renting Cost</td></tr>";
  foreach $count (0 .. $input{timetohold}) {
   printf("<tr><td class='HeaderTDHL'>%2.0f</td><td>\$%10.2f</td><td>\$%10.2f</td><td>\$%10.2f</td><td>\$%10.2f</td><td>\$%10.2f</td></tr>",$count,$rvb{pri, $count},$rvb{intr, $count},$rvb{loanamt, $count},$rvb{buycost, $count},$rvb{rentcost, $count});
  }
  print "</table>";
 }
}

sub doform {
if ($forms) {
 open(INPUTFORM,"rvb/rvbinpre.html") || die "Can't open your output form-pre. $!\n";
 while(<INPUTFORM>) {
  print $_;
 }
 close INPUTFORM;
}
#hidden
print qq!<FORM  METHOD=POST ACTION="rvb.cgi">!;
print qq!<INPUT TYPE="hidden" NAME="banana" VALUE="spiders">!;
print qq!<INPUT TYPE="hidden" NAME="c" VALUE="$input{c}">!;
print qq!<INPUT TYPE="hidden" NAME="hazins%" VALUE="0.35">!;
print qq!<INPUT TYPE="hidden" NAME="returnoninvestment%" VALUE="8">!;
print qq!<INPUT TYPE="hidden" NAME="points%" VALUE="0">!;
print qq!<INPUT TYPE="hidden" NAME="rentalincome_" VALUE="0">!;



#renter
print<<endBuyerQuestions;

<p><b>Buying</b></p>

<table>
<tr><td>\$  </td><td><INPUT TYPE="text" NAME="purchaseprice_">             </td><td>Purchase Price                     </td></tr>
<tr><td>\$  </td><td><INPUT TYPE="text" NAME="loanamount_">                </td><td>Loan Amount                        </td></tr>
<tr><td> %  </td><td><INPUT TYPE="text" NAME="interestrate%">              </td><td>Interest Rate                      </td></tr>
<tr><td>    </td><td><INPUT TYPE="text" NAME="loanterm">                   </td><td>Loan Term in years                 </td></tr>
<tr><td> %  </td><td><INPUT TYPE="text" NAME="closcosts%" VALUE="3">       </td><td>Closing Costs in Pts.              </td></tr>
<tr><td>\$  </td><td><INPUT TYPE="text" NAME="condodues_">                 </td><td>Yearly Homeowner's Insurance<br>/Condo Dues</td></tr>
<tr><td> %  </td><td><INPUT TYPE="text" NAME="propertytax%" VALUE="1.25">  </td><td>Property Tax                       </td></tr>
<tr><td> %  </td><td><INPUT TYPE="text" NAME="incometax%" VALUE="37">      </td><td>Income Tax (Fed/State)             </td></tr>
<tr><td> %  </td><td><INPUT TYPE="text" NAME="appreciation%" VALUE="5">    </td><td>Appreciation                       </td></tr>
<tr><td>    </td><td><INPUT TYPE="text" NAME="timetohold">                 </td><td>Time expected to Occupy            </td></tr>
</table>

endBuyerQuestions
print<<endRenterQuestions;
<p><b>Renting:</b></p>
<table>
<tr><td>\$</td><td><INPUT TYPE="text" NAME="rent_">             </td><td><p>Monthly Rent</p></td></tr>
<tr><td>\$</td><td><INPUT TYPE="text" NAME="rentersinsurance_"> </td><td><p>Insurance Premium</p></td></tr>
<tr><td>\$</td><td><INPUT TYPE="text" NAME="rentersrepairs_">   </td><td><p>Monthly Repairs</p></td></tr>
<tr><td>\$</td><td><INPUT TYPE="text" NAME="renterscarport_">   </td><td><p>Carport Fees</p></td></tr>
<tr><td>\$</td><td><INPUT TYPE="text" NAME="rentershaf_">       </td><td><p>Association Fees</p></td></tr>
<tr><td>\$</td><td><INPUT TYPE="text" NAME="rentersofees_">     </td><td><p>Other Costs<br>Associated<br>with Renting</p></td></tr>
</table>
endRenterQuestions
#control
print qq! <INPUT TYPE="radio" NAME="flow" VALUE="cashflow" CHECKED> Cash Flow Avg<BR>!;
print qq! <INPUT TYPE="radio" NAME="flow" VALUE="ecocost" > Economic Costs Avg<BR>!;
print qq! <INPUT TYPE="radio" NAME="flow" VALUE="firstmonth"> First Month Only<BR>!;
print qq!<HR>!;
print qq! <INPUT TYPE="submit" VALUE="Submit"> <INPUT TYPE="reset" VALUE="Reset">!;
print "</FORM><BR>";

if ($forms) {
 open(INPUTFORM,"rvb/rvbinpost.html") || die "Can't open your output form-pre. $!\n";
 while(<INPUTFORM>) {
  print $_;
 }
 close INPUTFORM;
}
print qq!<BR><HR><BR><A HREF="! . &CL_http($input{c}) . qq!"><H3>Return to Home Page</H3></A>! if ($input{c});


}

sub noweb {
local($in,$i,$key,$val);

$in = "";
# "global" vars
$in .= "&banana=spiders";
$in .= "&c=abcmortgage";
#list of input vars
#buyer
$in .= "&purchaseprice_=100,000";
$in .= "&loanamount_=80,000";
$in .= "&interestrate%=8";
$in .= "&loanterm=30";
$in .= "&points%=0";
$in .= "&incometax%=37";
$in .= "&hazins%=0.2";
$in .= "&closcosts%=2";
$in .= "&propertytax%=1";
$in .= "&returnoninvestment%=8";
$in .= "&rentalincome_=0";
$in .= "&condodues_=0";
$in .= "&appreciation%=5";
$in .= "&timetohold=30";
#renter
$in .= "&rent_=1,000";
$in .= "&rentersinsurance_=100";
$in .= "&rentersrepairs_=0";
$in .= "&renterscarport_=0";
$in .= "&rentersofees_=0";
#control  (flow = cashflow, ecocost, firstmonth)
$in .= "&flow=cashflow";

  @input = split(/&/,$in);
  foreach $i (1 .. $#input) {
   ($key, $val) = split(/=/,$input[$i],2);
   if (index($key,"\%") > $[) {
    $val = $val * 0.01;
    $key =~ s/\%//;
   }
   if (index($key,"_") > $[) {
    $val =~ s/\,//;
    $key =~ s/_//;
   }
   $input{$key} .= $val;
#   print "$key = $val\n";
  }
}

main:
{

$forms = true ;

 print &PrintHeader;
 if (&MethGet) {
  &ReadParse (*input);
  &doform;
 } else {
  &noweb if (! &ReadParse (*input));


  if ($forms) {
   open(INPUTFORM,"rvb/rvboutpre.html") || die "Can't open your output form-pre. $!\n";
   while(<INPUTFORM>) {
    print $_;
   }
   close INPUTFORM;
  }

   #guts of the calc
   &RentvsBuy;
   &dumpinfo;

  if ($forms) {
   open(INPUTFORM,"rvb/rvboutpost.html") || die "Can't open your output form-pre. $!\n";
   while(<INPUTFORM>) {
    print $_;
   }
   close INPUTFORM;
  }
  print qq!<BR><HR><BR><A HREF="! . &CL_http($input{c}) . qq!"><H3>Return to Home Page</H3></A>! if ($input{c});
 }
}