#!/usr/bin/perl

# gitolite shell, invoked from ~/.ssh/authorized_keys
# ----------------------------------------------------------------------

use FindBin;

BEGIN { $ENV{GL_BINDIR} = $FindBin::RealBin; }
BEGIN { $ENV{GL_LIBDIR} = "$ENV{GL_BINDIR}/lib"; }
use lib $ENV{GL_LIBDIR};
use Gitolite::Rc;
use Gitolite::Common;
use Gitolite::Conf::Load;

use strict;
use warnings;

# the main() sub expects ssh-ish things; set them up...
my $id = '';
if ( exists $ENV{G3T_USER} ) {
    $id = in_file();    # file:// masquerading as ssh:// for easy testing
} elsif ( exists $ENV{SSH_CONNECTION} ) {
    $id = in_ssh();
} elsif ( exists $ENV{REQUEST_URI} ) {
    $id = in_http();
} else {
    _die "who the *heck* are you?";
}

trigger('INPUT');

main($id);

gl_log('END') if $$ == $ENV{GL_TID};

exit 0;

# ----------------------------------------------------------------------

sub in_file {
    gl_log( 'file', "ARGV=" . join( ",", @ARGV ), "SOC=$ENV{SSH_ORIGINAL_COMMAND}" );

    if ( $ENV{SSH_ORIGINAL_COMMAND} =~ /git-\w+-pack/ ) {
        print STDERR "TRACE: gsh(", join( ")(", @ARGV ), ")\n";
        print STDERR "TRACE: gsh(SOC=$ENV{SSH_ORIGINAL_COMMAND})\n";
    }
    return 'file';
}

sub in_http {
    _die 'http not yet implemented...';
}

sub in_ssh {
    my $ip;
    ( $ip = $ENV{SSH_CONNECTION} || '(no-IP)' ) =~ s/ .*//;

    gl_log( 'ssh', "ARGV=" . join( ",", @ARGV ), "SOC=" . ( $ENV{SSH_ORIGINAL_COMMAND} || ''), "FROM=$ip" );

    $ENV{SSH_ORIGINAL_COMMAND} ||= '';
    my $soc = $ENV{SSH_ORIGINAL_COMMAND};
    $soc =~ s/[\n\r]+/<<newline>>/g;
    _die "I don't like newlines in the command: $soc\n" if $ENV{SSH_ORIGINAL_COMMAND} ne $soc;

    return $ip;
}

# ----------------------------------------------------------------------

# call this once you are sure arg-1 is the username and SSH_ORIGINAL_COMMAND
# has been setup (even if it's not actually coming via ssh).
sub main {
    my $id = shift;

    umask $rc{UMASK};

    # set up the user
    my $user = $ENV{GL_USER} = shift @ARGV;

    # set up the repo and the attempted access
    my ( $verb, $repo ) = parse_soc();    # returns only for git commands
    sanity($repo);
    $ENV{GL_REPO} = $repo;
    my $aa = ( $verb =~ 'upload' ? 'R' : 'W' );

    # auto-create?
    if ( repo_missing($repo) and access( $repo, $user, '^C', 'any' ) !~ /DENIED/ ) {
        require Gitolite::Conf::Store;
        Gitolite::Conf::Store->import;
        new_wild_repo( $repo, $user );
        gl_log( 'create', $repo, $user );
    }

    # a ref of 'any' signifies that this is a pre-git check, where we don't
    # yet know the ref that will be eventually pushed (and even that won't
    # apply if it's a read operation).  See the matching code in access() for
    # more information.
    unless ( $ENV{GL_BYPASS_ACCESS_CHECKS} ) {
        my $ret = access( $repo, $user, $aa, 'any' );
        trace( 1, "access($repo, $user, $aa, 'any')", "-> $ret" );
        trigger( 'ACCESS_1', $repo, $user, $aa, 'any', $ret );
        _die $ret . "\n(or you mis-spelled the reponame)" if $ret =~ /DENIED/;

        gl_log( "pre_git", $repo, $user, $aa, 'any', "-> $ret" );
    }

    trigger( 'PRE_GIT', $repo, $user, $aa, 'any', $verb );
    my $repodir = "'$rc{GL_REPO_BASE}/$repo.git'";
    _system( "git", "shell", "-c", "$verb $repodir" );
    trigger( 'POST_GIT', $repo, $user, $aa, 'any', $verb );
}

# ----------------------------------------------------------------------

sub parse_soc {
    my $soc = $ENV{SSH_ORIGINAL_COMMAND};
    $soc ||= 'info';

    my $git_commands = "git-upload-pack|git-receive-pack|git-upload-archive";
    if ( $soc =~ m(^($git_commands) '/?(.*?)(?:\.git(\d)?)?'$) ) {
        my ( $verb, $repo, $trace_level ) = ( $1, $2, $3 );
        $ENV{D} = $trace_level if $trace_level;
        _die "invalid repo name: '$repo'" if $repo !~ $REPONAME_PATT;
        trace( 2, "git command", $soc );
        return ( $verb, $repo );
    }

    # after this we should not return; caller expects us to handle it all here
    # and exit out

    _die "suspicious characters loitering about '$soc'" if $soc !~ $REMOTE_COMMAND_PATT;

    my @words = split ' ', $soc;
    if ( $rc{COMMANDS}{ $words[0] } ) {
        trace( 2, "gitolite command", $soc );
        _system( "gitolite", @words );
        exit 0;
    }

    _die "unknown git/gitolite command: $soc";
}

sub sanity {
    my $repo = shift;
    _die "'$repo' contains bad characters" if $repo !~ $REPONAME_PATT;
    _die "'$repo' ends with a '/'"         if $repo =~ m(/$);
    _die "'$repo' contains '..'"           if $repo =~ m(\.\.$);
}