#!@PERL@ -w
######################################################################
### gnc-fq-helper - present a scheme interface to Finance::Quote
### Copyright 2001 Rob Browning <rlb@cs.utexas.edu>
###
### This program is free software; you can redistribute it and/or
### modify it under the terms of the GNU General Public License as
### published by the Free Software Foundation; either version 2 of
### the License, or (at your option) any later version.
###
### This program is distributed in the hope that it will be useful,
### but WITHOUT ANY WARRANTY; without even the implied warranty of
### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
### GNU General Public License for more details.
###
### You should have received a copy of the GNU General Public License
### along with this program# if not, contact:
###
### Free Software Foundation           Voice:  +1-617-542-5942
### 51 Franklin Street, Fifth Floor    Fax:    +1-617-542-2652
### Boston, MA  02110-1301,  USA       gnu@gnu.org
######################################################################

use strict;
use English;
use FileHandle;

# Date::Manip provides ParseDate, ParseDateString, and UnixTime.
use Date::Manip;

=head1 NAME

gnc-fq-helper  -  allows gnucash to communicate with Finance::Quote
                  over pipes from guile. The requests and responses
                  are scheme forms.

=head1 SYNOPSIS

gnc-fq-helper

=head1 DESCRIPTION

Input: (on standard input - one entry per line and one line per
entry, and double quotes must only be delimiters, not string
content -- remember, we don't have a real scheme parser on the perl
side :>).

(<method-name> symbol symbol symbol ...)

where <method-name> indicates the desired Finance::Quote method.
One can list the many methods by running gnc-fq-check.

For currency quotes, the symbols alternate between the 'from'
and 'to' currencies.

For example:

(alphavantage "IBM" "LNUX")
(fidelity_direct "FBIOX" "FSELX")
(currency "USD" "AUD")

Output (on standard output, one output form per input line):

Schemified version of gnc-fq's output, basically an alist of
alists, as in the example below.  Right now, only the fields that
this script knows about (and knows how to convert to scheme) are
returned, so the conversion function will have to be updated
whenever Finance::Quote changes.  Currently you'll get symbol,
gnc:time-no-zone, and currency, and either last, nav, or price.
Fields with gnc: prefixes are non-Finance::Quote fields.
gnc:time-no-zone is returned as a string of the form "YYYY-MM-DD
HH:MM:SS", basically the unmolested (and underspecified) output of
the quote source.  It's up to you to know what it's proper timezone
really is.  i.e. if you know the time was in America/Chicago, you'll
need to convert it to that.

For example:

 $ echo '(alphavantage "CSCO" "JDSU" "^IXIC")' | ./gnc-fq-helper
(("CSCO" (symbol . "CSCO")
         (gnc:time-no-zone . "2001-03-13 19:27:00")
         (last . 20.375)
         (currency . "USD"))
 ("JDSU" (symbol . "JDSU")
         (gnc:time-no-zone . "2001-03-13 19:27:00")
         (last . 23.5625)
         (currency . "USD"))
("^IXIC" (symbol . ^IXIC)
         (gnc:time-no-zone . 2002-12-04 17:16:00)
         (last . 1430.35)
         (currency . failed-conversion)))

On error, the overall result may be #f, or on individual errors, the
list sub-item for a given symbol may be #f, like this:

 $ echo '(alphavantage "CSCO" "JDSU")' | ./gnc-fq-helper
(#f
 ("JDSU" (symbol . "JDSU")
         (gnc:time-no-zone . "2001-03-13 19:27:00")
         (last . 23.5625)
         (currency . "USD")))

further, errors may be stored with each quote as indicated in
Finance::Quote, and whenever the conversion to scheme data fails,
the field will have the value 'failed-conversion, and accordingly
this symbol will never be a legitimate conversion.

Exit status

0 - success
non-zero - failure

=cut

# Set a base date with the current time in the current TZ:
my $base_date = new Date::Manip::Date;
$base_date->parse("now");

# The methods we know about.  For now we assume they all have the same
# signature so this works OK.

sub check_modules {
  my @modules = qw(Finance::Quote Date::Manip);
  my @missing;

  foreach my $mod (@modules) {
    if (eval "require $mod") {
      $mod->import();
    }
    else {
      push (@missing, $mod);
    }
  }

  return unless @missing;

  print STDERR "\n";
  print STDERR "You need to install the following Perl modules:\n";
  foreach my $mod (@missing) {
    print STDERR "  ".$mod."\n";
  }

  print STDERR "\n";
  print STDERR "Use your system's package manager to install them,\n";
  print STDERR "or run 'gnc-fq-update' as root.\n";

  print "missing-lib";

  exit 1;
}

sub schemify_string {
  my($str) = @_;

  if(!$str) { return "failed-conversion"; }

  # FIXME: Is this safe?  Can we just double all backslashes and backslash
  # escape all double quotes and get the right answer?

  # double all backslashes.
  my $bs = "\\";
  $str =~ s/$bs$bs/$bs$bs/gmo;

  # escape all double quotes.
  # Have to do this because the perl-mode parser freaks out otherwise.
  my $dq = '"';
  $str =~ s/$dq/$bs$dq/gmo;
  return '"' . $str . '"';
}

sub schemify_boolean {
  my($bool) = @_;

  if($bool) {
    return "#t";
  } else {
    return "#f";
  }
}

sub schemify_num {
  my($numstr) = @_;
  # This is for normal numbers, not the funny ones like "2.346B".
  # For now we don't need to do anything.

  if(!$numstr) { return "failed-conversion"; }

  if($numstr =~ /^\s*(\d+(\.\d+)?([eE][+-]?\d+)?)$/o) {
    return "#e" . $1;
  } else {
    return "failed-conversion";
  }
}

# sub schemify_range {
#   #convert range in form ``num1 - num2'' to ``(num1 num2)''.
# }

sub get_quote_time {
  # return the date.
  my ($item, $quotehash) = @_;

  my $datestr = $$quotehash{$item, 'date'};
  my $timestr = $$quotehash{$item, 'time'};
  my $format = "%Y-%m-%d %H:%M:%S";
  my $result;

  if ($datestr) {
      my $parsestr = $datestr . " " . ($timestr ? $timestr : "12:00:00");
      my $date = $base_date->new();
      my $err = $date->parse($parsestr);
      if ($err) {
          print $date->err(), " $parsestr\n";
          $result = $base_date->printf($format);
      }
      else {
          $result = $date->printf($format);
      }
  } else {
      $result = $base_date->printf($format);
  }
  return("\"$result\"");
}

sub schemify_quote {
  my($itemname, $quotehash, $indentlevel) = @_;
  my $scmname = schemify_string($itemname);
  my $quotedata = "";
  my $field;
  my $data;

  if (!$$quotehash{$itemname, "success"}) {
    return schemify_boolean(0);
  }

  $field = 'symbol';
  if (($$quotehash{$itemname, $field})) {
    $data = schemify_string($$quotehash{$itemname, $field});
  } else {
    # VWD and a few others don't set the symbol field
    $data = schemify_string($itemname);
  }
  $quotedata .= "($field . $data)";

  $field = 'gnc:time-no-zone';
  $data = get_quote_time($itemname, $quotehash);
  $quotedata .= " ($field . $data)" if $data;

  $field = 'last';
  if (!($$quotehash{$itemname, $field})) {
    $field = 'nav';
  }
  if (!($$quotehash{$itemname, $field})) {
    $field = 'price';
  }

  $data = schemify_num($$quotehash{$itemname, $field});
  $quotedata .= " ($field . $data)";

  $field = 'currency';
  $data = schemify_string($$quotehash{$itemname, $field});
  $quotedata .= " ($field . $data)";

  return "($scmname $quotedata)";
}

sub schemify_quotes {
  my($symbols, $quotehash) = @_;
  my $resultstr = "";
  my $sym;
  my $separator = "";

  # we have to pass in @$items because Finance::Quote just uses the
  # mangled "$name$field string as the key, so there's no way (I know
  # of) to find out which stocks are in a given quotehash, just given
  # the quotehash.

  foreach $sym (@$symbols) {
    $resultstr .= $separator . schemify_quote($sym, $quotehash, 2);
    if(!$separator) { $separator = "\n "; }
  }
  return "($resultstr)\n";
}

sub parse_input_line {

  # FIXME: we need to rewrite parsing to handle commands modularly.
  # Right now all we do is hard-code "fetch".

  my($input) = @_;
  # Have to do this because the perl-mode parser freaks out otherwise.
  my $dq = '"';
  my @symbols;

  # Make sure we have an opening ( preceded only by whitespace.
  # and followed by a one word method name composed of [a-z_]+.
  # Also allow the '.' and '^' characters for stock indices.
  # Kill off the whitespace if we do and grab the command.
  if($input !~ s/^\s*\(\s*([\.\^a-z_]+)\s+//o) { return 0; }

  my $quote_method_name = $1;

  # Make sure we have an ending ) followed only by whitespace
  # and kill it off if we do...
  if($input !~ s/\s*\)\s*$//o) { return 0; }

  while($input) {
    # Items should look like "RHAT"
    # Grab RHAT and delete "RHAT"\s*
    if($input !~ s/^$dq([^$dq]+)$dq\s*//o) { return 0; }
    my $symbol = $1;
    push @symbols, $symbol;
  }

  my @result = ($quote_method_name, \@symbols);
  return \@result;
}

#---------------------------------------------------------------------------
# Runtime.

# Check for and load non-standard modules
check_modules ();

# Create a stockquote object.
my $quoter = Finance::Quote->new();
my $prgnam = "gnc-fq-helper";

# Disable default currency conversions.
$quoter->set_currency();

while(<>) {

  my $result = parse_input_line($_);

  if(!$result) {
    print STDERR "$prgnam: bad input line ($_)\n";
    exit 1;
  }

  my($quote_method_name, $symbols) = @$result;
  my %quote_data;

  if($quote_method_name =~ m/^currency$/) {
    my ($from_currency, $to_currency) = @$symbols;

    last unless $from_currency;
    last unless $to_currency;

    my $price = $quoter->currency($from_currency, $to_currency);
    my $inv_price = undef;
    # Sometimes price quotes are available in only one direction.
    unless (defined($price)) {
        $inv_price = $quoter->currency($to_currency, $from_currency);
        if (defined($inv_price)) {
            my $tmp = $to_currency;
            $to_currency = $from_currency;
            $from_currency = $tmp;
            $price = $inv_price;
        }
    }

    $quote_data{$from_currency, "success"} = defined($price);
    $quote_data{$from_currency, "symbol"} = $from_currency;
    $quote_data{$from_currency, "currency"} = $to_currency;
    $quote_data{$from_currency, "last"} = $price;

    my @new_symbols = ($from_currency);
    $symbols = \@new_symbols;
  } else {
    %quote_data = $quoter->fetch($quote_method_name, @$symbols);
  }

  if (%quote_data) {
    print schemify_quotes($symbols, \%quote_data);
  } else {
    print "#f\n";
  }

  STDOUT->flush();
}

exit 0;

__END__

# Keep this around in case we need to go back to complex per-symbol args.
#
#    while($input) {
#      # Items should look like "RHAT" "EST")
#      # Grab RHAT and delete ("RHAT"\s*
#      if($input !~ s/^\(\s*$dq([^$dq]+)$dq\s*//o) { return 0; }
#      my $symbol = $1;
#      my $timezone;
#      # Now grab EST or #f and delete \s*"EST") or #f)
#      if($input =~ s/^\s*$dq([^$dq]+)$dq\)\s*//o) {
#        $timezone = $1;
#      } else {
#        if($input =~ s/^\s*(\#f)\)\s*//o) {
#          $timezone = 0;
#        } else {
#          return 0;
#        }
#      }

#  sub get_quote_utc {
#    # return the date in utc epoch seconds, using $timezone if specified.
#    my ($item, $timezone, $quotehash) = @_;

#    if(!defined($timezone)) { return "failed-conversion"; }

#    my $datestr = $$quotehash{$item, 'date'};
#    my $timestr = $$quotehash{$item, 'time'};

#    if(!$datestr) {
#      return "failed-conversion";
#    }
#    my $parsestr = $datestr;
#    if($timestr) {
#      $parsestr .= " $timestr";
#    }

#    if($timezone) {
#      # Perform a conversion.
#      $parsestr = Date_ConvTZ(ParseDate($parsestr), $timezone, 'UTC');
#    }
#    my $result = UnixDate($parsestr, "%s");
#    if($result !~ /^(\+|-)?\d+$/) {
#      $result = "failed-conversion";
#    }
#    return $result;
#  }

## Local Variables:
## mode: perl
## End:
