#This script is designed to run with Understand - CodeCheck
use base qw(Understand::Codecheck);
use strict;


use constant ERR1 => 'Violation: %2 "%1" (which has external linkage) defined multiple times.';
use constant ERR2 => 'Violation: %2 "%1" (which has external linkage) is not defined.';


sub register_tr_text {
	my $check = shift;
	$check->add_tr_text(ERR1);
}

sub name { '3-2-4 Is An identifier with external linkage shall have exactly one definition.' }

sub description { '3-2-4 (Required) An identifier with external linkage shall have exactly one definition.' }

sub detailed_description { <<'END_DESC'
<p><b>Rationale</b><br>
It is undefined behaviour	if	an	identifier	is	used	for	which	multiple	definitions	exist	(in	different	
translation	units)	or	no	definition	exists	at	all.	With	the	exception	of	templates	and	inline	functions,	
multiple	definitions	in	different	translation	units	are	not	permitted,	even	if	the	definitions	are	the	
same.</p>
<b>Example</b><pre style="margin-top:0;padding-top:0;">
// file1.cpp 
int32_t i = 0;
// file2.cpp 
int32_t i = 1;      // Non-compliant

<p>To ignore all overloads select the option below.</p>
END_DESC
}

sub test_language {
	my $language = shift;
	return $language eq 'C++';
}

sub test_entity { 0 }

sub test_global { 1 }

sub define_options { 
	my $check = shift;
	$check->option->checkbox('overloads','Ignore Overloads',0);
}

sub check {
	my $check = shift;
	
  my %seen;
  my %notdefined;
	foreach my $file ($check->get_files) {
      return if $check->is_abort();
	  foreach my $ref ($file->filerefs("~implicit","global object ~static ~unknown, function ~static ~unknown" ,0)) {
        if($ref->kind->check("define")){
          push(@{$seen{$ref->ent->longname}},$ref);
          $notdefined{$ref->ent->longname}=0;
        }else{
          $notdefined{$ref->ent->longname}=$ref unless exists $notdefined{$ref->ent->longname};
        }
      
	  }
	}
	foreach my $refArray(keys %seen){
      my @array = @{$seen{$refArray}};
	  my @violations;
      next unless @array > 1;
	  
	  if($check->option->lookup('overloads')){
		  foreach my $i (@array){
				my $count = 0;
			foreach my $j (@array){
				$count++ if $i->ent->parent && $j->ent->parent && $i->ent->parent->id == $j->ent->parent->id;
			}
			push(@violations, $i)unless $count > 1;
		  }
	  }
	  else{
		@violations = @array;
	  }
	  
      foreach my $ref (@violations){
        $check->violation($ref->ent, $ref->file, $ref->line, $ref->column, ERR1, $ref->ent->longname, $ref->ent->kindname);
      }
    }
	
  foreach my $ref (values%notdefined){
    next unless $ref;
	next if($ref->ent->name && $ref->ent->name eq "operator=");
    $check->violation($ref->ent, $ref->file, $ref->line, $ref->column, ERR2, $ref->ent->longname, $ref->ent->kindname);
  }
	
	
	return;
}