#!/usr/bin/env perl

#
# Script to help out with syncing cpan distros.
#
# Does the following:
#    - Fetches the package list from CPAN. Finds the current version of
#      the given package. [1]
#    - Downloads the relevant tarball; unpacks the tarball;. [1]
#    - Clean out the old directory (git clean -dfx)
#    - Moves the old directory out of the way, moves the new directory in place.
#    - Restores any .gitignore file.
#    - Removes files from @IGNORE and EXCLUDED
#    - git add any new files.
#    - git rm any files that are gone.
#    - Remove the +x bit on files in t/
#    - Remove the +x bit on files that don't have in enabled in the current dir
#    - Restore files mentioned in CUSTOMIZED
#    - Adds new files to MANIFEST
#    - Runs a "make" (assumes a configure has been run)
#    - Cleans up
#    - Runs tests for the package
#    - Runs the porting tests
#
# [1]  If the --tarball option is given, then CPAN is not consulted.
#      --tarball should be the path to the tarball; the version is extracted
#      from the filename -- but can be overwritten by the --version option.
#
# TODO:  - Delete files from MANIFEST
#        - Update Porting/Maintainers.pl
#        - Optional, run a full test suite
#        - Handle complicated FILES
#
# This is an initial version; no attempt has been made yet to make this
# portable. It shells out instead of trying to find a Perl solution.
# In particular, it assumes wget, git, tar, chmod, perl, make, and rm
# to be available.
#
# Usage: perl Porting/sync-with-cpan <module>
#        where <module> is the name it appears in the %Modules hash
#        of Porting/Maintainers.pl
#

package Maintainers;

use 5.010;

use strict;
use warnings;
use Getopt::Long;
no  warnings 'syntax';

$| = 1;

die "This does not like top level directory"
     unless -d "cpan" && -d "Porting";

our @IGNORABLE;
our %Modules;

use autodie;

require "Porting/Maintainers.pl";

my %IGNORABLE    = map {$_ => 1} @IGNORABLE;

my $package      = "02packages.details.txt";
my $package_url  = "http://www.cpan.org/modules/$package";
my $package_file = "/tmp/$package";


GetOptions ('tarball=s'  =>  \my $tarball,
            'version=s'  =>  \my $version,
             force       =>  \my $force,)
        or  die "Failed to parse arguments";

die "Usage: $0 module [args] [cpan package]" unless @ARGV == 1 || @ARGV == 2;

my ($module)  = shift;
my  $cpan_mod = @ARGV ? shift : $module;


my  $info         = $Modules {$module} or die "Cannot find module $module";
my  $distribution = $$info {DISTRIBUTION};

my @files         = glob $$info {FILES};
if (@files != 1 || !-d $files [0] || $$info {MAP}) {
    say "This looks like a setup $0 cannot handle (yet)";
    unless ($force) {
        say "Will not continue without a --force option";
        exit 1;
    }
    say "--force is in effect, so we'll soldier on. Wish me luck!";
}


chdir "cpan";

my  $pkg_dir      = $$info {FILES};
    $pkg_dir      =~ s!.*/!!;

my ($old_version) = $distribution =~ /-([0-9.]+)\.tar\.gz/;

my  $o_module     = $module;
if ($cpan_mod =~ /-/ && $cpan_mod !~ /::/) {
    $cpan_mod =~ s/-/::/g;
}

#
# Find the information from CPAN.
#
my $new_file;
my $new_version;
unless ($tarball) {
    #
    # Poor man's cache
    #
    unless (-f $package_file && -M $package_file < 1) {
        system wget => $package_url, '-qO', $package_file;
    }

    my  $new_line = `grep '^$cpan_mod ' $package_file`
                     or die "Cannot find $cpan_mod on CPAN\n";
    chomp $new_line;
    (undef, $new_version, my $new_path) = split ' ', $new_line;
    $new_file = (split '/', $new_path) [-1];

    my $url = "http://search.cpan.org/CPAN/authors/id/$new_path";
    say "Fetching $url";
    #
    # Fetch the new distro
    #
    system wget => $url, '-qO', $new_file;
}
else {
    $new_file     = $tarball;
    $new_version  = $version // ($new_file =~ /-([0-9._]+)\.tar\.gz/) [0];
}

my  $old_dir      = "$pkg_dir-$old_version";
my  $new_dir      = "$pkg_dir-$new_version";

say "Cleaning out old directory";
system git => 'clean', '-dfxq', $pkg_dir;

say "Unpacking $new_file";

system tar => 'xfz', $new_file;

say "Renaming directories";
rename $pkg_dir => $old_dir;
rename $new_dir => $pkg_dir;


if (-f "$old_dir/.gitignore") {
    say "Restoring .gitignore";
    system git => 'checkout', "$pkg_dir/.gitignore";
}

my @new_files = `find $pkg_dir -type f`;
chomp @new_files;
@new_files = grep {$_ ne $pkg_dir} @new_files;
s!^[^/]+/!! for @new_files;
my %new_files = map {$_ => 1} @new_files;

my @old_files = `find $old_dir -type f`;
chomp @old_files;
@old_files = grep {$_ ne $old_dir} @old_files;
s!^[^/]+/!! for @old_files;
my %old_files = map {$_ => 1} @old_files;

#
# Find files that can be deleted.
#
my @EXCLUDED_QR;
my %EXCLUDED_QQ;
if ($$info {EXCLUDED}) {
    foreach my $entry (@{$$info {EXCLUDED}}) {
        if (ref $entry) {push @EXCLUDED_QR => $entry}
        else            {$EXCLUDED_QQ {$entry} = 1}
    }
}

my @delete;
my @commit;
my @gone;
FILE:
foreach my $file (@new_files) {
    next if -d "$pkg_dir/$file";   # Ignore directories.
    next if $old_files {$file};    # It's already there.
    if ($IGNORABLE {$file}) {
        push @delete => $file;
        next;
    }
    if ($EXCLUDED_QQ {$file}) {
        push @delete => $file;
        next;
    }
    foreach my $pattern (@EXCLUDED_QR) {
        if ($file =~ /$pattern/) {
            push @delete => $file;
            next FILE;
        }
    }
    push @commit => $file;
}
foreach my $file (@old_files) {
    next if -d "$old_dir/$file";
    next if $new_files {$file};
    push @gone => $file;
}

#
# Find all files with an exec bit
#
my @exec = `find $pkg_dir -type f -perm +111`;
chomp @exec;
my @de_exec;
foreach my $file (@exec) {
    # Remove leading dir
    $file =~ s!^[^/]+/!!;
    if ($file =~ m!^t/!) {
        push @de_exec => $file;
        next;
    }
    # Check to see if the file exists; if it doesn't and doesn't have
    # the exec bit, remove it.
    if ($old_files {$file}) {
        unless (-x "$old_dir/$file") {
            push @de_exec => $file;
        }
    }
}

#
# No need to change the +x bit on files that will be deleted.
#
if (@de_exec && @delete) {
    my %delete = map {+"$pkg_dir/$_" => 1} @delete;
    @de_exec = grep {!$delete {$_}} @de_exec;
}

say "unlink $pkg_dir/$_" for @delete;
say "git add $pkg_dir/$_" for @commit;
say "git rm -f $pkg_dir/$_" for @gone;
say "chmod a-x $pkg_dir/$_" for @de_exec;

print "Hit return to continue; ^C to abort "; <STDIN>;

unlink "$pkg_dir/$_"                      for @delete;
system git   => 'add', "$pkg_dir/$_"      for @commit;
system git   => 'rm', '-f', "$pkg_dir/$_" for @gone;
system chmod => 'a-x', "$pkg_dir/$_"      for @de_exec;

#
# Restore anything that is customized.
# We don't really care whether we've deleted the file - since we
# do a git restore, it's going to be resurrected if necessary.
#
if ($$info {CUSTOMIZED}) {
    say "Restoring customized files";
    foreach my $file (@{$$info {CUSTOMIZED}}) {
        system git => "checkout", "$pkg_dir/$file";
    }
}

chdir "..";
if (@commit) {
    say "Fixing MANIFEST";
    my $MANIFEST      = "MANIFEST";
    my $MANIFEST_SORT = "$MANIFEST.sorted";
    open my $fh, ">>", $MANIFEST;
    say $fh "cpan/$pkg_dir/$_" for @commit;
    close $fh;
    system perl => "Porting/manisort", '--output', $MANIFEST_SORT;
    rename $MANIFEST_SORT => $MANIFEST;
}


print "Running a make ... ";
system "make > make.log 2>&1" and die "Running make failed, see make.log";
print "done\n";

#
# Must clean up, or else t/porting/FindExt.t will fail.
# Note that we can always retrieve the orginal directory with a git checkout.
#
print "About to clean up; hit return or abort (^C) "; <STDIN>;

chdir "cpan";
system rm => '-r', $old_dir;
unlink $new_file unless $tarball;


#
# Run the tests. First the test belonging to the module, followed by the
# the tests in t/porting
#
chdir "../t";
say "Running module tests";
my @test_files = `find ../cpan/$pkg_dir -name '*.t' -type f`;
chomp @test_files;
my $output = `./perl TEST @test_files`;
unless ($output =~ /All tests successful/) {
    say $output;
    exit 1;
}

print "Running tests in t/porting ";
my @tests = `ls porting/*.t`;
chomp @tests;
my @failed;
foreach my $t (@tests) {
    my @not = `./perl -I../lib -I.. $t | grep ^not | grep -v "# TODO"`;
    print @not ? '!' : '.';
    push @failed => $t if @not;
}
print "\n";
say "Failed tests: @failed" if @failed;


print "Now you ought to run a make; make test ...\n";

say "Do not forget to update Porting/Maintainers.pl before committing";
say "$o_module is now version $new_version";


__END__