#!/usr/bin/perl -w

# Copyright (C) 2005, 2006, 2007 Apple Inc.  All rights reserved.
# Copyright (C) 2011 Carl Lobo.  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. 
# 3.  Neither the name of Apple Inc. ("Apple") nor the names of
#     its contributors may be used to endorse or promote products derived
#     from this software without specific prior written permission. 
#
# THIS SOFTWARE IS PROVIDED BY APPLE AND ITS 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 APPLE OR ITS CONTRIBUTORS 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.

# Updates a development environment to the new WebKitAuxiliaryLibrary

use strict;
use warnings;

use Archive::Zip qw( :ERROR_CODES );
use File::Copy;
use File::Find;
use File::Spec;
use File::Temp ();
use FindBin;
use HTTP::Date qw(str2time time2str);
use HTTP::Request;
use LWP::Simple;
use LWP::UserAgent;
use POSIX;
use lib $FindBin::Bin;
use webkitdirs;

if ($#ARGV != 1) {
    die <<EOF;
Usage:
        update-webkit-dependancy <URL with the dependancy zip file> <*prefix dir inside zip without filename>

        * If filename is requirements.zip and the contents of the zipfile are "requirements/x" then prefix = "."
        * If filename is xyz.zip and the contents of the zipfile are xyz/abc/x" then prefix = "abc"
        * x is lib or include or bin.
EOF
}

sub lastModifiedToUnixTime($);
sub getLibraryName($);

# Time in seconds that the new zip file must be newer than the old for us to
# consider them to be different. If the difference in modification time is less
# than this threshold, we assume that the files are the same. We need this
# because the zip file is served from a set of mirrors with slightly different
# Last-Modified times.
my $newnessThreshold = 30;

my $libsURL = shift;
my $prefixInZip = shift;
my $sourceDir = sourceDir();
my $file = getLibraryName($libsURL);
my $zipFile = "$file.zip"; 
my $webkitLibrariesDir = $ENV{'WEBKIT_LIBRARIES'} || File::Spec->catdir($sourceDir, "WebKitLibraries", "win");
my $tmpRelativeDir = File::Temp::tempdir("webkitlibsXXXXXXX", TMPDIR => 1, CLEANUP => 1);
my $tmpAbsDir = File::Spec->rel2abs($tmpRelativeDir);
my $ua = LWP::UserAgent->new();
$ua->env_proxy;

print "Checking Last-Modified date of $zipFile...\n";

my $response = $ua->get($libsURL);

unless ($response->is_success) {
    print "Could not access $libsURL:\n" . $response->headers_as_string . "\n";
    print "You may not be connected to the internet. Attempting to build without updating.\n";
    exit 0;
}

my $content_type = $response->header('Content-Type');
my $document_length = $response->header('Content-Length');
my $modified_time = str2time($response->header('Last-Modified')); 

if (defined $modified_time) {
    print STDERR "Located a file of type $content_type, of size $document_length.\n";
    open NEW, ">", File::Spec->catfile($tmpAbsDir, "$file.headers");
    print NEW "Last-Modified: " . time2str($modified_time) . "\n";
    close NEW;
} else {
    #Note: Neither GitHub nor DropBox emit the Last-Modified HTTP header, so fall back to a file
	#containing the necessary information if we do not receive the information in our initial query.
    my $headerURL = $libsURL;
    $headerURL =~ s/\.zip$/\.headers/;

    my $result = getstore($headerURL, File::Spec->catfile($tmpAbsDir, "$file.headers"));

    if (!is_success($result)) {
        print STDERR "Couldn't check Last-Modified date of new $zipFile.\n";
        print STDERR "Response was: $result.\n";
        print STDERR "Please ensure that Perl can use LWP::Simple to connect to HTTPS urls, and that $libsURL is reachable.\n";
        print STDERR "You may have to run \$ cpan LWP::Protocol::https\n";

        if (! -f File::Spec->catfile($webkitLibrariesDir, "$file.headers")) {
            print STDERR "Unable to check Last-Modified date and no version of $file to fall back to.\n";
            exit 1;
        }

        print STDERR "Falling back to existing version of $file.\n";
        exit 0;
    }
}

if (open NEW, File::Spec->catfile($tmpAbsDir, "$file.headers")) {
    my $new = lastModifiedToUnixTime(<NEW>);
    close NEW;

    if (defined $new && open OLD, File::Spec->catfile($webkitLibrariesDir, "$file.headers")) {
        my $old = lastModifiedToUnixTime(<OLD>);
        close OLD;
        if (defined $old && abs($new - $old) < $newnessThreshold) {
            print "Current $file is up to date\n";
            exit 0;
        }
    }
}

print "Downloading $zipFile...\n\n";
print "$libsURL\n";
my $result = getstore($libsURL, File::Spec->catfile($tmpAbsDir, $zipFile));
die "Couldn't download $zipFile!" if is_error($result);

my $zip = Archive::Zip->new(File::Spec->catfile($tmpAbsDir, $zipFile));
$result = $zip->extractTree("", $tmpAbsDir);
die "Couldn't unzip $zipFile." if $result != AZ_OK;

print "\nInstalling $file...\n";

sub wanted
{
    my $relativeName = File::Spec->abs2rel($File::Find::name, File::Spec->catdir($tmpAbsDir, $file, $prefixInZip));
    my $destination = File::Spec->catfile($webkitLibrariesDir, $relativeName);

    if (-d $_) {
        mkdir $destination;
        return;
    }

    copy($_, $destination);
}

File::Find::find(\&wanted, File::Spec->catfile($tmpAbsDir, $file));

$result = move(File::Spec->catfile($tmpAbsDir, "$file.headers"), $webkitLibrariesDir);
print STDERR "Couldn't move $file.headers to $webkitLibrariesDir" . ".\n" if $result == 0;

print "The $file has been sucessfully installed in\n $webkitLibrariesDir\n";
exit;

sub lastModifiedToUnixTime($)
{
    my ($str) = @_;

    $str =~ /^Last-Modified: (.*)$/ or return;
    return str2time($1);
}

sub getLibraryName($)
{
    my $url = shift;
    $url =~ m#/([^/]+)\.zip$#;
    return $1;
}