#!/usr/bin/perl

use strict;
use warnings;

my( $errorto ) = 'jrayhawk+piny.svcs.cs.pdx.edu@omgwallhack.org'; # Email address to send horrible errors to.
my( $reponame, $email, @errors, $wikilisttempfile, $cgitrctempfile);

if ( ( ! scalar $ARGV[0] ) or ( scalar $ARGV[1] ) or ( $ARGV[0] !~ /^[a-z0-9][a-z0-9+.-]+$/ ) ) {
  print( "Usage: newrepo REPONAME\n" );
  print( "  REPONAME must consist only of lower case letters (a-z), digits (0-9), plus (+) and minus (-) signs, and periods (.).\n" );
  print( "  REPONAME must be at least two characters long and must start with an alphanumeric character.\n" );
  exit( 1 );
} else {
  $reponame = $ARGV[0];
};

# We want to check to see if
#   1) $reponame already exists in some form so we don't try to create it, and
#   2) $reponame is only partially created, in which case we want to email someone who can sanity check and fix it.
open (PASSWD, '/etc/passwd');
while(<PASSWD>) {
  if( $_ =~ /^$ENV{SUDO_USER}:.+?:.+?:.+?:(.+?):/ ) { $email = $1; }; # While we're here, may as well grab the email address.
  if( $_ =~ /^ikiwiki-$reponame:/				) { push( @errors, "user ikiwiki-$reponame already exists!\n"); };
};
close(PASSWD);
open (GROUP, '/etc/group');
while(<GROUP>) {
  if( $_ =~ /^git-$reponame:/					) { push( @errors, "group git-$reponame already exists!\n"); };
};
close(GROUP);
if( -d "/srv/git/$reponame.git"					) { push( @errors, "/srv/git/$reponame.git already exists!\n"); };
if( -d "/srv/ikiwiki/$reponame"					) { push( @errors, "/srv/ikiwiki/$reponame already exists!\n"); };
if( -d "/srv/www/piny.svcs.cs.pdx.edu/$reponame"		) { push( @errors, "/srv/www/piny.svcs.cs.pdx.edu/$reponame already exists!\n"); };
if( -d "/srv/www/cgi.piny.svcs.cs.pdx.edu/repos/$reponame"	) { push( @errors, "/srv/www/cgi.piny.svcs.cs.pdx.edu/repos/$reponame already exists!\n"); };
if( -f "/etc/ikiwiki/piny/$reponame.setup"			) { push( @errors, "/etc/ikiwiki/piny/$reponame.setup already exists!\n"); };
if( -f "/etc/ikiwiki/wikilist.d/$reponame"			) { push( @errors, "/etc/ikiwiki/wikilist.d/$reponame already exists!\n"); };
if( -f "/etc/apache2/piny-available/$reponame"			) { push( @errors, "/etc/apache2/piny-available/$reponame already exists!\n"); };
if( -f "/etc/cgitrc.d/$reponame"			        ) { push( @errors, "/etc/cgitrc.d/$reponame already exists!\n"); };

if( @errors ) {
  if( @errors == 10 ) { # Everything's fine, nothing is broken
    print( "$reponame already exists!\n" );
  } else {              # IT'S ARMAGEDDON
    open ( MAIL, "|/usr/lib/sendmail -t" );
    print( MAIL "To: $errorto\n" );
    print( MAIL "From: newrepo\@piny.svcs.cs.pdx.edu\n" );
    print( MAIL "Subject: Piny error: $ENV{SUDO_USER} found inconsistent $reponame in the creation process!\n" );
    print( MAIL "MIME-Version: 1.0\n" );
    print( MAIL "Content-Type: text/plain; charset=us-ascii\n" );
    print( MAIL "\n" );
    print( MAIL "@errors\n" );
    close( MAIL );
    print( "$reponame already exists but is in an inconsistent state! The Piny admins probably screwed up; they have been notified and will take a look at it.\n" );
  };
  exit( 2 );
};


# CREATE USER/GROUPS
unless( system( "mkdir /srv/git/$reponame.git" ) == 0 ) { # We need a locking or atomic operation as our first to check against simultaneous execution.
  print( "I suspect that you are attempting to create the same repo multiple times simultaneously.\n" );
  exit( 3 );
};
system( "/usr/sbin/addgroup --quiet git-$reponame" );
system( "/usr/sbin/adduser --quiet --system --group --gecos $reponame ikiwiki-$reponame" );
system( "/usr/sbin/adduser --quiet ikiwiki-$reponame git-$reponame | grep -v 'Adding user'" );
system( "/usr/sbin/adduser --quiet $ENV{SUDO_USER} git-$reponame | grep -v 'Adding user '" );

# CREATE REPO
system( "GIT_DIR=/srv/git/$reponame.git /usr/bin/git init --template=/srv/git-template.git --quiet --shared" );
open ( DESC, ">/srv/git/$reponame.git/description" );
print( DESC "$reponame owned by $email" );
close( DESC );
# ln -f post-receive /srv/git/$reponame.git/hooks/ # turn on e-mail commit notices
system( "/bin/chown -R $ENV{SUDO_USER}.git-$reponame /srv/git/$reponame.git/" );
system( "/bin/chown -R ikiwiki-$reponame.ikiwiki-$reponame /srv/git/$reponame.git/hooks/" );
system( "/bin/touch /srv/git/$reponame.git/git-daemon-export-ok" );

# WRITE IKIWIKI SETUP FILE
open ( SETUP, ">/etc/ikiwiki/piny/$reponame.setup" );
print( SETUP
'#!/usr/bin/perl
# Configuration file for ikiwiki.
# Passing this to ikiwiki --setup will make ikiwiki generate wrappers and
# build the wiki.
#
# Remember to re-run ikiwiki --setup any time you edit this file.

use IkiWiki::Setup::Standard {
	wikiname => \'' . $reponame . '\', # PINY
	adminemail => \'' . $email . '\', # PINY
	srcdir => \'/srv/ikiwiki/' . $reponame . '\', # PINY
	destdir => \'/srv/www/piny.svcs.cs.pdx.edu/' . $reponame . '\', # PINY
	url => \'http://piny.svcs.cs.pdx.edu/' . $reponame . '\', # PINY
	cgiurl => \'https://cgi.piny.svcs.cs.pdx.edu/repos/' . $reponame . '/ikiwiki.cgi\', # PINY
	historyurl => \'https://cgi.piny.svcs.cs.pdx.edu/gitweb.cgi?p=' . $reponame . '.git;a=history;f=[[file]]\', # PINY
        diffurl => \'https://cgi.piny.svcs.cs.pdx.edu/gitweb.cgi?p=' . $reponame . ';a=blobdiff;f=doc/[[file]];h=[[sha1_to]];hp=[[sha1_from]];hb=[[sha1_commit]];hpb=[[sha1_parent]]\', # PINY

	templatedir => "/srv/templates",
	underlaydir => "/etc/ikiwiki/share/underlay",

	rcs => "git",
	gitorigin_branch => "origin",
	gitmaster_branch => "master",

	wrappers => [
		{
			cgi => 1,
			wrapper => \'/srv/www/cgi.piny.svcs.cs.pdx.edu/repos/' . $reponame . '/ikiwiki.cgi\', # PINY
			wrappermode => "06755",
                        wrappergroup => \'git-' . $reponame . '\', # PINY
		},
		{
			wrapper => \'/srv/git/' . $reponame . '.git/hooks/post-update\', # PINY
			wrappermode => "06755",
                        wrappergroup => \'git-' . $reponame . '\', # PINY

			notify => 0,
		},
	],

	# Generate rss feeds for blogs?
	rss => 1,
	# Generate atom feeds for blogs?
	atom => 0,
	# Include discussion links on all pages?
	discussion => 0,
	# To exclude files matching a regexp from processing. This adds to
	# the default exclude list.
	#exclude => qr/*\.wav/,
	# To change the extension used for generated html files.
	#htmlext => "htm",
	# Time format (for strftime)
	#timeformat => "%c",
	# Locale to use. Must be a UTF-8 locale.
	#locale => "en_US.UTF-8",
	# Only send cookies over SSL connections.
	sslcookie => 1,
	# Logging settings:
	verbose => 0,
	syslog => 1,
	# To link to user pages in a subdirectory of the wiki.
	#userdir => "users",
	# To create output files named page.html rather than page/index.html.
	usedirs => 1,
	# Simple spam prevention: require an account-creation password.
	#account_creation_password => "example",
	# Use new "!"-prefixed preprocessor directive syntax
	prefix_directives => 1,
	httpauth => 1,
	# To add plugins, list them here.
	add_plugins => [qw{sidebar toc meta table tag httpauth attachment rename remove autoindex map teximg version edittemplate}],
	disable_plugins => [qw{openid passwordauth}],
	teximg_prefix => \'\\documentclass{scrartcl}
\\usepackage[version=3]{mhchem}
\\usepackage{amsmath}
\\usepackage{amsfonts}
\\usepackage{amssymb}
\\pagestyle{empty}
\\newcommand{\unit}[1]{\\ensuremath{\\, \\mathrm{#1}}}
\\begin{document}\',

	teximg_dvipng => 1,

	# For use with the tag plugin, make all tags be located under a
	# base page.
	tagbase => "tag",

	# For use with the search plugin if your estseek.cgi is located
	# somewhere else.
	#estseek => "/usr/lib/estraier/estseek.cgi",
}');
close( SETUP );
open ( WIKILIST, '>>/etc/ikiwiki/wikilist' );
print( WIKILIST "ikiwiki-$reponame /etc/ikiwiki/piny/$reponame.setup\n" );
close( WIKILIST );

# WRITE APACHE CONFIG
open ( APACHE, ">/etc/apache2/piny-available/$reponame" );
print( APACHE '<Directory /srv/www/cgi.piny.svcs.cs.pdx.edu/repos/' . $reponame . '>
	AuthPAM_Enabled on
	AuthGROUP_Enabled on
	AuthPAM_FallThrough off
	AuthBasicAuthoritative off
	AuthType Basic
	AuthName "User access to ' . $reponame . ' repository needed."
	Require group git-' . $reponame . '
</Directory>' );
close( APACHE );
link( "/etc/apache2/piny-available/$reponame", "/etc/apache2/piny-enabled/$reponame");
system( '/etc/init.d/apache2 reload | grep -v "Reloading web server config: apache2."' );


# CREATE IKIWIKI WORKING DIR
system( "/usr/bin/git clone --quiet /srv/git/$reponame /srv/ikiwiki/$reponame" );
mkdir( "/srv/www/piny.svcs.cs.pdx.edu/$reponame" );
mkdir( "/srv/www/cgi.piny.svcs.cs.pdx.edu/repos/$reponame" );
system( "/bin/chown -R ikiwiki-$reponame /srv/ikiwiki/$reponame /srv/www/piny.svcs.cs.pdx.edu/$reponame /srv/www/cgi.piny.svcs.cs.pdx.edu/repos/$reponame" );

open ( WIKILIST, ">/etc/ikiwiki/wikilist.d/$reponame" ); # Maybe someday ikiwiki will support wikilist.d.
print( WIKILIST "ikiwiki-$reponame /etc/ikiwiki/piny/$reponame.setup\n" ); # In the meantime, we fake it.
close( WIKILIST );
$wikilisttempfile = `/bin/mktemp`;
chomp( $wikilisttempfile );
system( "/bin/cat /etc/ikiwiki/wikilist.d/* > $wikilisttempfile" );
chmod ( 0644, $wikilisttempfile );
system( "/bin/mv $wikilisttempfile /etc/ikiwiki/wikilist" ); # This is marginally racy, but the consequences are probably ignorable.

open ( CGITRC, ">/etc/cgitrc.d/$reponame" ); # Maybe someday cgit will support cgitrc.d.
print( CGITRC
"repo.url=$reponame
repo.path=/srv/git/$reponame.git
repo.desc=$reponame
repo.owner=$email

" ); # In the meantime, we fake it.
close( CGITRC );
$cgitrctempfile = `/bin/mktemp`;
chomp( $cgitrctempfile );
system( "/bin/cat /etc/cgitrc.d/* > $cgitrctempfile" );
chmod ( 0644, $cgitrctempfile );
system( "/bin/mv $cgitrctempfile /etc/cgitrepos" ); # This is marginally racy, but the consequences are minor.

# COMPILE
system( "/usr/bin/sudo -u ikiwiki-$reponame /usr/bin/ikiwiki --setup /etc/ikiwiki/piny/$reponame.setup | grep -v 'successfully generated'" );