asset gain report added (-A)

README

@@ -403,7 +403,12 @@ To enable pricing reports, three options are possible:
   at time of purchase.  Thus, totals in the register and balance
   report reflect the total amount spent.
 
-**-Q FILE** ::
+**-A** ::
+  Report commodities in terms of their net gain, which is: the market
+  value minus the cost basis.  A balance report using this option
+  shows very quickly the performance of investments.
+
+**-Q** ::
   When needed (see the =-L= option) pricing quotes are obtained by
   calling the script =getquote= (a sample Perl script is provided, but
   the interface is kept simple so replacements may be made).
@@ -413,8 +418,16 @@ To enable pricing reports, three options are possible:
   pricing data is older than MINS minutes.  The default is one day,
   or 1440 minutes.
 
-Note that the =-B=, =-T=, =-V=, and =-P= and =-Q= flags are all
+**-p ARG** ::
-mutually exclusive.  Whichever option appears last is used.
+  If a string, such as "COMM=$1.20", the commodity COMM will be
+  reported only in terms of the conversion factor, which supersedes
+  all other pricing histories for that commodity.  This can be used to
+  perform arbitrary value substitutions.  For example, to report the
+  value of your dollars in terms of the ounces of gold they would buy,
+  use: -p "$=0.00280112 AU" (or whatever the current exchange rate
+  is).
+
+Note that the =-B=, =-T=, =-V=, and =-A= are mutually exclusive.
 
 ** Accounts and Inventories
 
@@ -1169,7 +1182,12 @@ launches =vi= to let you confirm that the entry looks appropriate.
   at time of purchase.  Thus, totals in the register and balance
   report reflect the total amount spent.
 
-**-Q FILE** ::
+**-A** ::
+  Report commodities in terms of their net gain, which is: the market
+  value minus the cost basis.  A balance report using this option
+  shows very quickly the performance of investments.
+
+**-Q** ::
   When needed (see the =-L= option) pricing quotes are obtained by
   calling the script =getquote= (a sample Perl script is provided, but
   the interface is kept simple so replacements may be made).

reports.cc

@@ -18,9 +18,10 @@ static bool full_names     = false;
 static bool print_monthly  = false;
 static bool gnuplot_safe   = false;
 
-static bool cost_basis  = false;
+static bool cost_basis     = false;
-static bool use_history = false;
+static bool use_history    = false;
-static bool get_quotes  = false;
+static bool net_gain       = false;
+static bool get_quotes     = false;
        long pricing_leeway = 24 * 3600;
        std::string price_db;
 
@@ -88,6 +89,23 @@ static amount * resolve_amount(amount *      amt,
   else if (cost_basis) {
     value = amt->value();
   }
+  else if (net_gain) {
+    value = amt->street(when ? when : (have_ending ? &end_date : NULL),
+			use_history, get_quotes);
+    amount * basis = amt->value();
+    if (value->commdty() == basis->commdty()) {
+      basis->negate();
+      value->credit(basis);
+    } else {
+      // If the commodities do not match, ignore this amount by
+      // returning a zeroed value.
+      delete basis;
+      basis = value->copy();
+      basis->negate();
+      value->credit(basis);
+      delete basis;
+    }
+  }
   else {
     value = amt->street(when ? when : (have_ending ? &end_date : NULL),
 			use_history, get_quotes);
@@ -992,7 +1010,7 @@ int main(int argc, char * argv[])
 
   int c;
   while (-1 != (c = getopt(argc, argv,
-			   "+Bb:Ccd:Ee:Ff:Ghi:L:l:MN:nP:p:QRSsTUVv"))) {
+			   "+ABb:Ccd:Ee:Ff:Ghi:L:l:MN:nP:p:QRSsTUVv"))) {
     switch (char(c)) {
     case 'b':
       have_beginning = true;
@@ -1059,13 +1077,20 @@ int main(int argc, char * argv[])
       get_quotes = true;
       break;
 
-    case 'B':
-      cost_basis = true;
-      // fall through...
     case 'V':
       use_history = true;
       break;
       
+    case 'B':
+      cost_basis = true;
+      use_history = true;
+      break;
+
+    case 'A':
+      net_gain = true;
+      use_history = true;
+      break;
+
     case 'T':
       cost_basis  = false;
       use_history = false;
@@ -1147,7 +1172,7 @@ int main(int argc, char * argv[])
     }
   }
 
-  if (use_history && ! price_db.empty())
+  if (use_history && ! cost_basis && ! price_db.empty())
     entry_count += parse_ledger_file(main_ledger, price_db, regexps,
 				     command == "equity");