#*******************************************************************************
# Copyright (c) 1997-2004, Perforce Software, Inc.  All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
# 
# 1.  Redistributions of source code must retain the above copyright
#     notice, this list of conditions and the following disclaimer.
# 
# 2.  Redistributions in binary form must reproduce the above copyright
#     notice, this list of conditions and the following disclaimer in the
#     documentation and/or other materials provided with the distribution.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL PERFORCE SOFTWARE, INC. BE LIABLE FOR ANY
# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
# LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#*******************************************************************************

use ExtUtils::MakeMaker;
use Getopt::Long;
use English;
use Cwd;
use Cwd 'abs_path';
use Config;
use strict;

#$ExtUtils::MakeMaker::Verbose = 1;

our $APIDIR = undef;
our $MAX_API_VERSION = undef;

#
# Check the Perforce API version from the Version file
#
sub extract_api_version
{
	my $path = shift;
	my $cwd = getcwd();
	my $apiver = undef; 

	foreach my $vfile ( "$path/Version", "$path/sample/Version" )
	{
	    next unless ( -e $vfile );
	    open( VF, $vfile ) or die( "Can't open $vfile" );
	    while( <VF> )
	    {
		if( /^RELEASE = (.*) ;/ )
		{
		    $apiver = encode_api_version( $1 );
		    last;
		}
	    }
	    close( FH );
	}

	my $tries = 3;
	while( !defined( $apiver ) && --$tries )
	{
	    print( "Unable to determine API version string\n" );
	    print( "Enter API version: " );
	    $apiver = <STDIN>;
	    $apiver = encode_api_version( $apiver );
	}
	die( "Aborting: API version not provided" ) unless $apiver;
	printf( "Found %d.%d Perforce API in %s\n",
       		api_major( $apiver ), api_minor( $apiver ), $path );
	return $apiver;
}

#
# Encode an API version string into an integer
# 
sub encode_api_version( $ )
{
    my $vs = shift;
    if( defined $vs && $vs =~ /(\d+)(\.|\s)(\d+)/ )
    {
	return (($1 << 8 ) | $3 );
    }
    return undef;
}

sub api_major( $ )
{
    my $v = shift;
    return $v >> 8;
}

sub api_minor( $ )
{
    my $v = shift;
    return $v & 0xff;
}


sub is_api_dir( $ )
{
    my $dir = shift;
    return 0 unless ( -d $dir );
    return 1 if( -e "$dir/Version" );
    return 1 if( -e "$dir/sample/Version" );
    return 0;
}
    
#
# Check that they're using an API version we can digest.
#
sub check_api_version( $ )
{
    my $api_ver = shift;
    my $max_ver_name = sprintf( "%d.%d", api_major( $MAX_API_VERSION ),
					 api_minor( $MAX_API_VERSION ) );

    return 1 if( $api_ver <= $MAX_API_VERSION );
    print <<EOF;

This version of P4Perl was designed for use with the $max_ver_name
Perforce C++ API. Using it with later releases may not work.

EOF
    print( "Do you wish to continue? (y/n): " );
    my $answer = <STDIN>;
    chomp( $answer );
    return 0 unless $answer eq "y";
    return 1;
}

sub get_api_dir()
{
    if( defined( $APIDIR ) && is_api_dir( $APIDIR ) )
    {
	return $APIDIR;
    }

    # Get the path to the Perforce API
    my $apipath = undef;
    my $tries = 3;
    $apipath = $APIDIR if( defined( $APIDIR ) );
    while( !defined( $apipath ) && --$tries )
    {
	print <<EOF;

This extension requires the Perforce API in order to be built. If you
do not yet have the API files, then download them from ftp://ftp.perforce.com
before continuing.

EOF

	print( "Where is the Perforce API to be found: " );
	$apipath = <STDIN>;
	$apipath =~ s/\n//;

	# Filthy support for ~/ type paths ( NOT ~user/ though! )
	$apipath =~ s#\~/#$ENV{HOME}/#;
	$apipath = abs_path( $apipath );
	$apipath = undef unless( is_api_dir( $apipath ) );
    }
    
    die ( "Aborting - no API directory provided" ) unless $apipath;


    return $apipath;
}

#
# Add the Perforce libraries to the linker configuration
#
sub add_p4_libs( $$$ )
{
    my $cfg = shift;		# Perl's pre-set config
    my $flags = shift;		# Flags we want to add
    my $apidir = shift;		# Our API directory

    my $libdir = $apidir;
    $libdir = "$libdir/lib" if( -d "$libdir/lib" );

    $flags->{'LIBS'} = [];
    if( defined( $cfg->{LIBS} ) )
    {
	my $libs = $cfg->{LIBS};
	foreach my $libset (@$libs )
	{
	    push( @{$flags->{LIBS}}, 
		"-L$libdir -lclient -lrpc -lsupp $libset" );
	}
    }
    else
    {
	push( @{$flags->{LIBS}},  "-L$libdir -lclient -lrpc -lsupp" );
    }
}

#
# Add the Perforce headers to the includes
#
sub add_p4_hdrs( $$ )
{
    my $flags = shift;
    my $apipath = shift;

    $apipath = "$apipath/include/p4" if( -d "$apipath/include/p4" );
    $flags->{ 'INC' }		= "-I$apipath -Ilib";
}


#
# This sub adds the Perforce API path to the header includes and libs 
# used by the compiler. It's called by WriteMakefile.
#
sub config_sub
{
	my $class = shift;
	my $href = shift;

	# First warn them about potential build problems
	print <<EOF;

Warning: This extension uses C++ and requires that you use the C++ 
	 compiler to compile the XSUB file ( normally just a C compiler
	 is required ). 

	 If your build fails with a plethora of errors, then check
	 the following first: 

	 1. That the correct compilers are being used.

	 2. That you're using the correct build of the Perforce API. 

	 3. That you have defined the correct OS_xxxxx macro for your
	    platform ( see the Perforce API documentation for more info )

	 See hints/linux.pl to see how it should be done.

EOF
	# Now find that API!
	my $flags = {};

	# Get the path to the Perforce API
	my $apiver = undef;
	my $apipath = get_api_dir(); # dies if API not found
	$apiver = extract_api_version( $apipath );

	#
	# Abort if the user's decided not to press ahead with a newer
	# version of the API than this version was written for
	#
	exit( 1 ) unless ( check_api_version( $apiver ) );

	$href->{ 'DEFINE' } .= " -DP4API_VERSION=$apiver";

	#
	# Set the build date
	#
	my $now = time();
	$href->{ 'DEFINE' } .= " -DBUILD_DATE=$now";

	#
	# Decide how const_char should be handled. If the API is 2006.1 or
	# later, then const_char should always be 'const char'. If it's 
	# earlier, then go with the hint (if any) or default to 'char'
	#
	my $sixone = encode_api_version( "2006.1" );
	if( $apiver ge $sixone )
	{
	    $href->{ 'DEFINE' } .= qq( -Dconst_char="const char");
	}
	elsif( defined $href->{CONST_CHAR_HINT} )
	{
	    $href->{ 'DEFINE' } .= qq( -Dconst_char="$href->{CONST_CHAR_HINT}");
	}
	else
	{
	    $href->{ 'DEFINE' } .= qq( -Dconst_char="char");
	}
	delete $href->{CONST_CHAR_HINT} if( defined($href->{CONST_CHAR_HINT}) );

	add_p4_libs( $href, $flags, $apipath );
	add_p4_hdrs( $flags, $apipath );

	#
	# Make sure we're not linking with -debug on Windows - because the
	# linker chokes.
	# 
	if( $^O eq "MSWin32" )
	{
	    $flags->{ 'LDDLFLAGS' } = $Config{ 'lddlflags' };
	    $flags->{ 'LDDLFLAGS' } =~ s/ -debug//g;
	}

	#
	#
	# Last thing to do is to get the address of their perforce 
	# server for the tests
	print <<EOF;

The test suite needs to know where your Perforce server is. The tests
are non-invasive and no new data will be added to your depot during
the tests

EOF
	print( "Enter the address of your Perforce server: [perforce:1666]: ");
	my $p4port = <STDIN>;
	$p4port =~ s/\n//;
	$p4port = "perforce:1666" if ( $p4port =~ /^$/ );

	open( IN, "test.pl.skel" ) or die( "Can't open test.pl.skel! ");
	open( OUT, ">test.pl" ) or die( "Can't create test.pl" );

	my $line;
	while ( $line = <IN> )
	{
	    $line =~ s/__P4PORT__/$p4port/g;
	    print( OUT $line );
	}
	close( IN );
	close( OUT );

	return $flags;
}

# Ensure that the clientuserperl interface gets built.
sub MY::postamble
{
'
$(MYEXTLIB): lib/Makefile
	cd lib && $(MAKE) $(PASSTHRU)
';
}

#*******************************************************************************
#* 			START OF MAIN SCRIPT
#*******************************************************************************

#
# This is the version of the API that was current when this build of
# P4Perl was produced. It may build with later releases, but it may
# not. 
#
$MAX_API_VERSION = encode_api_version( "2007.2" );

my %flags = (
	    'NAME'		=> 'P4',
	    'VERSION_FROM'	=> 'P4.pm', # finds $VERSION
	    'PREREQ_PM'		=> {}, # e.g., Module::Name => 1.1
	    'MYEXTLIB'		=> 'lib/libp4$(LIB_EXT)',
	    'XSOPT'		=> '-C++ -prototypes',
	    'CONFIGURE'		=> \&config_sub,
	    'clean'		=> { FILES => 'test.pl' },
	);

our $APIDIR = undef;
my $result = GetOptions ( "apidir=s" => \$APIDIR );

WriteMakefile( %flags );