#!/usr/bin/perl

# Copyright (c) 2010 Symbian Foundation Ltd

# This component and the accompanying materials are made available

# under the terms of the License "Eclipse Public License v1.0"

# which accompanies this distribution, and is available

# at the URL "http://www.eclipse.org/legal/epl-v10.html".

#

# Initial Contributors:

# Mike Kinghan, mikek@symbian.org for Symbian Foundation Ltd - initial contribution.

# Script to get a copy of upstream package at the baseline revision in

# ../baseline.txt and patch it to be the same as this package.

use strict;

use get_baseline;

use perl_run;

use set_epocroot;

use get_hostplatform_dir;

use check_os;

use File::Spec;

use File::Temp 'tempfile';

use Cwd 'abs_path';

use Getopt::Long;

my $help =0;

my $baseline_dir = '';

my $patch_in = '';

sub usage(*);

sub usage_error($);

sub help();

sub get_old_baseline_dir($);

sub regen_patch_file($);

GetOptions("help=i" => \$help, "patch-file=s" => \$patch_in,

	"baseline-dir=s" => \$baseline_dir) or usage_error("Usage error");

if ($help) {

	help();

}

if (!$baseline_dir) {

	usage_error("Need -b, --baseline-dir");

}

print ">>> Testing for patch\n";

my $patch_test = "patch --version";

print ">>> Executing: $patch_test\n";

my $rc = system($patch_test);

die "*** Error: can't execute the patch tool ***", if ($rc);

$baseline_dir = abs_path($baseline_dir);

perl_run("get_upstream.pl $baseline_dir") and die $!;

set_epocroot();

my $epocroot = $ENV{'EPOCROOT'};

if (!$patch_in) {

	my $baseline_rev = get_baseline();

	$patch_in = File::Spec->catfile("$epocroot","build","cross-plat-dev-utils",

		"patch-files","diffs","patch-$baseline_rev.patch");

}

die "*** Error: can't find patch file \"$patch_in\" ***", unless ( -f $patch_in);

$baseline_dir = File::Spec->catfile("$baseline_dir","build");

my $pnum = compute_pnum($patch_in);

my $patch_cmd = "patch -d $baseline_dir -p$pnum < $patch_in";

print ">>> Executing: $patch_cmd\n";

exit system($patch_cmd) >> 8;

sub usage(*)

{

	local *OUT = shift;

	print OUT "This script gets a copy of upstream package at the " .

		" baseline revision in ../baseline.txt and patches it to be the same ".

		"as this package\n" .

		"Options:\n" .

		"-h, --help:              Display this help and exit\n" .

		"-p, --patch-file FILE:   Apply the patch file FILE. " .

			"Default ./patch-files/diffs/patch-N, where N is the baseline revision\n" .

		"-b, --baseline-dir DIR:  The upstream baseline will be cloned into " .

			"DIR if this does not seem to have been done already. Otherwise " .

			"DIR/build will be udated to the baseline revision before patching\n" .

		"*** It is assumed that the command 'patch' will invoke the patch tool " .

		"***\n";

}

sub usage_error($)

{

	my $diag = shift;

	print STDERR "*** $diag ***\n";

	usage(*STDERR);

	exit 1;

}

sub help()

{

	usage(*STDOUT);

	exit 0;

}

sub get_old_baseline_dir($)

{

	my $patch_file = shift;

	open PATCH,"<$patch_file" or die $!;

	my $line = <PATCH>;

	if ($line !~ /^## diff generated by diff_upstream.pl/) {

		print "!!! Warning: patch file was not created by diff_upstream.pl. " .

			"proceeding at risk !!!\n";

	} else {

		$line = <PATCH>;

	} 

	close PATCH;

	die "*** Error: \"$patch_file\" is empty ***", unless ($line);

	my @words = split(/ /,$line);

	if (@words < 3) {

		die "*** Error: can't make sense of \"$patch_file\" as a patch file ***";

	}

	my $old_baseline_file = $words[-2];

	my $path_punct = os_is_windows() ? '\\' : '/';

	my @old_baseline_parts = split(/$path_punct/,$old_baseline_file);

	while($old_baseline_parts[-1] ne 'build') {

		pop @old_baseline_parts;

	}

	my $old_base_line_dir = join($path_punct,@old_baseline_parts);

	print ">>> Patch-file seems to have been diffed from \"$old_base_line_dir\"\n";

	return $old_base_line_dir;

}

sub compute_pnum($)

{

	my $patch_file = shift;

	my $old_base_line_dir = get_old_baseline_dir($patch_file);

	my $path_punct = os_is_windows() ? '\\' : '\/';

	my @old_base_line_dir_parts = split(/$path_punct/,$old_base_line_dir);

	return @old_base_line_dir_parts;

}