use strict;
use warnings;

package Module::Install::PRIVATE::Mongo;

use Module::Install::Base;
use Config;
use Config::AutoConf 0.22;
use Path::Tiny 0.052;
use File::Spec::Functions qw/catdir/;
use Cwd; 

our @ISA = qw{Module::Install::Base};

use constant {
    HAS_GCC => $Config{ccname} =~ /gcc/ ? 1 : 0,
};

sub check_for_outdated_win_gcc {
	return if $ENV{MONGODB_NO_WIN32_GCC_CHECK};
	return if ! HAS_GCC;

	local $@;
	my $gcc_ver = eval {
		my ( $v ) = split / /, $Config{gccversion};
		"$v";
	};
	die "Could not identify gcc version in '$Config{gccversion}' due to:\n$@" if !$gcc_ver or $@;
        my $gcc_vstring = eval "v$gcc_ver";
	die "Could not parse gcc version '$gcc_ver':\n$@" if !$gcc_vstring or $@;
	my $min_work_ver = "4.6.3";
	my $min_work_vstring = eval "v$min_work_ver";
	return if $gcc_vstring ge $min_work_vstring;

	die <<"END";
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Your gcc is version '$gcc_ver'.
The highest known incompatible version of gcc is '4.4.7'.
The lowest  known   compatible version of gcc is '$min_work_ver'.

Your gcc version is highly unlikely to be able to compile BSON, since the
libraries/headers that come with it is incompatible with our version of libbson.

We're aborting here forcibly so you will see this message. You have the
following options at this point:

1. set MONGODB_NO_WIN32_GCC_CHECK to any value to ignore this message and retry

2. if you know C, try and help us by upgrading our libbson, patches welcome!

3. install a newer gcc, '$min_work_ver' or higher

4. install Strawberry 5.16.3 or higher, their gcc versions are compatible

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
END
}

sub mongo {
    my ($self, @mongo_vars) = @_;

    my $ccflags = $self->makemaker_args->{CCFLAGS} || $Config{ccflags};
    $ccflags = "" unless defined $ccflags;

    $ccflags .= " -Wall -Wextra -Wuninitialized -Wdeclaration-after-statement"
        if HAS_GCC && ( $ENV{AUTHOR_TESTING} || $ENV{AUTOMATED_TESTING} );

    # Perl on older Centos doesn't come with this by default
    $ccflags .= " -D_GNU_SOURCE"
        if HAS_GCC && $ccflags !~ /-D_GNU_SOURCE/;

    # MSWin32 requires newer gcc (if using gcc)
    if ( $^O eq 'MSWin32' ) {
        check_for_outdated_win_gcc;
    }

    # openbsd needs threaded perl *or* single-threaded but with libpthread, so
    # we check specifically for that
    if ($^O eq 'openbsd') {
        my $has_libpthread = qx{/usr/bin/ldd $Config{perlpath}} =~ /libpthread/;
        die "OS unsupported: OpenBSD support requires a perl linked with libpthread"
            unless $has_libpthread;
    }

    # check for 64-bit
    if ($Config{use64bitint}) {
        $ccflags .= " -DMONGO_USE_64_BIT_INT";
    }

    # check for big-endian
    my $endianess = $Config{byteorder};
    if ($endianess == 4321 || $endianess == 87654321) {
        $ccflags .= " -DMONGO_BIG_ENDIAN=1 ";
        if ( $] lt '5.010' ) {
            die "OS unsupported: Perl 5.10 or greater is required for big-endian platforms";
        }
    }

    # needed to compile bson library
    $ccflags .= " -DBSON_COMPILATION ";

    my $conf = $self->configure_bson;

    if ($conf->{BSON_WITH_OID32_PT} || $conf->{BSON_WITH_OID64_PT}) {
        my $pthread = $^O eq 'solaris' ? " -pthreads " : " -pthread ";
        $ccflags .= $pthread;
        my $ldflags = $self->makemaker_args->{LDFLAGS};
        $ldflags = "" unless defined $ldflags;
        $self->makemaker_args( LDFLAGS => "$ldflags $pthread" );
    }

    if ( $conf->{BSON_HAVE_CLOCK_GETTIME} ) {
        my $libs = $self->makemaker_args->{LIBS};
        $libs = "" unless defined $libs;
        $self->makemaker_args( LIBS => "$libs -lrt" );
    }

    $self->makemaker_args( CCFLAGS => $ccflags );

    $self->xs_files;

    $self->makemaker_args( INC   => '-I. -Ibson' );

    return;
}

sub xs_files {
    my ($self) = @_;
    my (@clean, @OBJECT, %XS);

    for my $xs (<xs/*.xs>) {
        (my $c = $xs) =~ s/\.xs$/.c/i;
        (my $o = $xs) =~ s/\.xs$/\$(OBJ_EXT)/i;

        $XS{$xs} = $c;
        push @OBJECT, $o;
        push @clean, $o;
    }

    for my $c (<*.c>, <bson/*.c>) {
        (my $o = $c) =~ s/\.c$/\$(OBJ_EXT)/i;

        push @OBJECT, $o;
        push @clean, $o;
    }

    $self->makemaker_args(
        clean  => { FILES => join(q{ }, @clean) },
        OBJECT => join(q{ }, @OBJECT),
        XS     => \%XS,
    );

    $self->postamble(<<'HERE');
$(OBJECT) : perl_mongo.h

cover : pure_all
	HARNESS_PERL_SWITCHES=-MDevel::Cover make test

ptest : pure_all
	HARNESS_OPTIONS=j9 make test

HERE

    return;
}

# Quick and dirty autoconf substitute
sub configure_bson {
    my ($self) = @_;

    my $conf = $self->probe_bson_config;

    my $config_guts = path("bson/bson-config.h.in")->slurp;
    for my $key ( %$conf ) {
        $config_guts =~ s/\@$key\@/$conf->{$key}/;
    }
    path("bson/bson-config.h")->spew($config_guts);

    return $conf;
}

sub probe_bson_config {
    my ($self) = @_;
    my $ca = Config::AutoConf->new;
    $ca->push_lang("C");
    my %conf;

    ##/*
    ## * Define to 1234 for Little Endian, 4321 for Big Endian.
    ## */
    $conf{BSON_BYTE_ORDER} = $Config{byteorder} =~ /^1234/ ? '1234' : '4321';

    ##/*
    ## * Define to 1 if you have stdbool.h
    ## */
    $conf{BSON_HAVE_STDBOOL_H} = $Config{i_stdbool} ? 1 : 0;

    ##/*
    ## * Define to 1 for POSIX-like systems, 2 for Windows.
    ## */
    $conf{BSON_OS} = $^O eq 'MSWin32' ? 2 : 1;


    ##/*
    ## * Define to 1 if you have clock_gettime() available.
    ## */
    ## XXX also needs to link -lrt for this to work
    {
        my $ca = Config::AutoConf->new;
        $ca->push_libraries('rt');
        $conf{BSON_HAVE_CLOCK_GETTIME} = $ca->link_if_else(
            $ca->lang_call("", "clock_gettime")
        ) ? 1 : 0;
    }

    ##/*
    ## * Define to 1 if you have strnlen available on your platform.
    ## */
    $conf{BSON_HAVE_STRNLEN} = $ca->link_if_else(
        $ca->lang_call("", "strnlen")
    ) ? 1 : 0;

    ##/*
    ## * Define to 1 if you have snprintf available on your platform.
    ## */
    $conf{BSON_HAVE_SNPRINTF} = $Config{d_snprintf} ? 1 : 0;

    ##/*
    ## * Define to 1 if your system requires {} around PTHREAD_ONCE_INIT.
    ## * This is typically just Solaris 8-10.
    ## */

    ## pthread-related configuration
    if ( $^O eq 'MSWin32' ) {
        $conf{BSON_PTHREAD_ONCE_INIT_NEEDS_BRACES} = 0;
    }
    else {

        $conf{BSON_PTHREAD_ONCE_INIT_NEEDS_BRACES} = $ca->link_if_else(<<'HERE') ? 0 : 1;
#include <pthread.h>
pthread_once_t foo = PTHREAD_ONCE_INIT;
int
main ()
{
;
return 0;
}
HERE

    }

    ##/*
    ## * Define to 1 if we have access to GCC 32-bit atomic builtins.
    ## * While this requires GCC 4.1+ in most cases, it is also architecture
    ## * dependent. For example, some PPC or ARM systems may not have it even
    ## * if it is a recent GCC version.
    ## */
    $conf{BSON_HAVE_ATOMIC_32_ADD_AND_FETCH} = $ca->link_if_else(<<'HERE') ? 1 : 0;
#include <stdint.h>
int
main ()
{
    int32_t seq = 0;
    __sync_fetch_and_add_4(&seq, (int32_t)1);
    return seq;
}
HERE

    ##/*
    ## * Similarly, define to 1 if we have access to GCC 64-bit atomic builtins.
    ## */
    $conf{BSON_HAVE_ATOMIC_64_ADD_AND_FETCH} = $ca->link_if_else(<<'HERE') ? 1 : 0;
#include <stdint.h>
int
main ()
{
    int64_t seq = 0;
    __sync_fetch_and_add_8(&seq, (int64_t)1);
    return seq;
}
HERE


    ##/*
    ## * Define to 1 if you have _set_output_format (VS2013 and older).
    ## */
    $conf{BSON_NEEDS_SET_OUTPUT_FORMAT} = 0;

    ##/*
    ## * Define to 1 if you have struct timespec available on your platform.
    ## */
    $conf{BSON_HAVE_TIMESPEC} = $ca->check_type( 'timespec' );

    ##/*
    ## * Define to 1 if you want extra aligned types in libbson
    ## */
    $conf{BSON_EXTRA_ALIGN} = 0;

    ##/*
    ## * Define to 1 if _Decimal128 (BID format) is available on your platform.
    ## */
    $conf{BSON_HAVE_DECIMAL128} = $ca->check_type( '_Decimal128' );

    return \%conf;
}

1;