#!/usr/bin/perl

use strict;
use JSON;
use CGI::Carp qw(fatalsToBrowser);
use DBI;


require 'cgi-lib.pl';

print "Content-type: text/html\n\n";

my $in=&ReadParse;
my $str_js=$in->{cmd};

my $user = 'root';
my $passwd = '';
my $db = DBI->connect('DBI:mysql:test:localhost', $user, $passwd);

#print $db;
my $cmd = decode_json( $str_js );
if ($cmd->[0] eq 'GET') {
	my $data=$cmd->[1];
	my $where=&where($data->{where});
	my $ord=&orderBy($data->{orderBy});
	my $query=qq(
	select * from $data->{from}
	  $where $ord ;
	);
	my $sth = $db->prepare($query);
	$sth->execute;
	my $num_rows = $sth->rows;
	my $res=[];
	for (my $i=0; $i<$num_rows; $i++) {
	    my $a = $sth->fetchrow_hashref;
	    $a->{_class}=$data->{from};
	    push @{$res}, $a;
	}
	$sth->finish;
	$db->disconnect;
	print encode_json($res);
} elsif ($cmd->[0] eq 'POST' or $cmd->[0] eq 'PUT' ) {
    my $data=$cmd->[1];
    my $values=&values($data);
    my $query =qq(
      insert into $data->{_class} $values ;
    );
    my $sth=$db->prepare($query);
    my $res=$sth->execute;
    if ($res) { print encode_json(["OK"]); }
    else { print encode_json(["Fail : ".$sth->errstr]); }
}

sub values {
   my $d=shift;
   my @names;
   my @values;
   while (my ($k,$v)=each %{$d}) {
      push @names, $k;
      push @values, "'$v'" ; 
   }
   " (".join(", ",@names).") values (".join(", ",@values).")";
}

sub where {
  my $w=shift;
  my @res;
  while (my ($k,$v)=each %{$w}) {
      push @res, "$k='$v'" ; 
  }
  if (@res==0) {return ""}
  "where ".join(" and ",@res);
}
sub orderBy {
  my $ord=shift;
  if ($ord) {" order by $ord ";}
  else {"";}
}