#!/usr/bin/perl
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use strict;
use warnings;
use 5.010;

use vars qw($Nobody $SystemUser $item);

# fix lib paths, some may be relative
BEGIN { # BEGIN RT CMD BOILERPLATE
    require File::Spec;
    require Cwd;
    my @libs = ("lib", "local/lib");
    my $bin_path;

    for my $lib (@libs) {
        unless ( File::Spec->file_name_is_absolute($lib) ) {
            $bin_path ||= ( File::Spec->splitpath(Cwd::abs_path(__FILE__)) )[1];
            $lib = File::Spec->catfile( $bin_path, File::Spec->updir, $lib );
        }
        unshift @INC, $lib;
    }

}

use Term::ReadKey;
use Getopt::Long;
use Data::GUID;

$| = 1; # unbuffer all output.

my %args = (
    package => 'RT',
);
GetOptions(
    \%args,
    'action=s',
    'force', 'debug',
    'dba=s', 'dba-password=s', 'prompt-for-dba-password', 'package=s',
    'datafile=s', 'datadir=s', 'skip-create', 'root-password-file=s',
    'package=s', 'ext-version=s',
    'upgrade-from=s', 'upgrade-to=s',
    'help|h',
);

no warnings 'once';
if ( $args{help} || ! $args{'action'} ) {
    require Pod::Usage;
    Pod::Usage::pod2usage({ verbose => 2 });
    exit;
}

require RT;
RT->LoadConfig();
RT->InitClasses();

# Force warnings to be output to STDERR if we're not already logging
# them at a higher level
RT->Config->Set( LogToSTDERR => 'warning')
    unless ( RT->Config->Get( 'LogToSTDERR' )
             && RT->Config->Get( 'LogToSTDERR' ) =~ /^(debug|info|notice)$/ );
RT::InitLogging();

# get customized root password
my $root_password;
if ( $args{'root-password-file'} ) {
    open( my $fh, '<', $args{'root-password-file'} )
      or die "Couldn't open 'args{'root-password-file'}' for reading: $!";
    $root_password = <$fh>;
    chomp $root_password;
    my $min_length = RT->Config->Get('MinimumPasswordLength');
    if ($min_length) {
        die
"password needs to be at least $min_length long, please check file '$args{'root-password-file'}'"
          if length $root_password < $min_length;
    }
    close $fh;
}


# check and setup @actions
my @actions = grep $_, split /,/, $args{'action'};
if ( @actions > 1 && $args{'datafile'} ) {
    print STDERR "You can not use --datafile option with multiple actions.\n";
    exit(-1);
}
foreach ( @actions ) {
    unless ( /^(?:init|create|drop|schema|acl|indexes|coredata|insert|upgrade)$/ ) {
        print STDERR "$0 called with an invalid --action parameter.\n";
        exit(-1);
    }
    if ( /^(?:init|drop|upgrade)$/ && @actions > 1 ) {
        print STDERR "You can not mix init, drop or upgrade action with any action.\n";
        exit(-1);
    }
}

# convert init to multiple actions
my $init = 0;
if ( $actions[0] eq 'init' ) {
    if ($args{'skip-create'}) {
        @actions = qw(schema coredata insert);
    } else {
        @actions = qw(create schema acl coredata insert);
    }
    $init = 1;
}

# set options from environment
foreach my $key(qw(Type Host Name User Password)) {
    next unless exists $ENV{ 'RT_DB_'. uc $key };
    print "Using Database$key from RT_DB_". uc($key) ." environment variable.\n";
    RT->Config->Set( "Database$key", $ENV{ 'RT_DB_'. uc $key });
}

my $db_type = RT->Config->Get('DatabaseType') || '';
my $db_host = RT->Config->Get('DatabaseHost') || '';
my $db_port = RT->Config->Get('DatabasePort') || '';
my $db_name = RT->Config->Get('DatabaseName') || '';
my $db_user = RT->Config->Get('DatabaseUser') || '';
my $db_pass = RT->Config->Get('DatabasePassword') || '';

# load it here to get error immidiatly if DB type is not supported
require RT::Handle;

if ( $db_type eq 'SQLite' && !File::Spec->file_name_is_absolute($db_name) ) {
    $db_name = File::Spec->catfile($RT::VarPath, $db_name);
    RT->Config->Set( DatabaseName => $db_name );
}

my $dba_user = $args{'dba'} || $ENV{'RT_DBA_USER'} || RT->Config->Get('DatabaseAdmin') || '';
my $dba_pass = $args{'dba-password'} || $ENV{'RT_DBA_PASSWORD'};

if ($args{'skip-create'}) {
    $dba_user = $db_user;
    $dba_pass = $db_pass;
} else {
    if ( !$args{force} && ( !defined $dba_pass || $args{'prompt-for-dba-password'} ) ) {
        $dba_pass = get_dba_password();
        chomp $dba_pass if defined($dba_pass);
    }
}

my $version_word_regex = join '|', RT::Handle->version_words;
my $version_dir = qr/^\d+\.\d+\.\d+(?:$version_word_regex)?\d*$/;

print "Working with:\n"
    ."Type:\t$db_type\nHost:\t$db_host\nPort:\t$db_port\nName:\t$db_name\n"
    ."User:\t$db_user\nDBA:\t$dba_user" . ($args{'skip-create'} ? ' (No DBA)' : '') . "\n";

my $package = $args{'package'} || 'RT';
my $ext_version = $args{'ext-version'};
my $full_id = Data::GUID->new->as_string;

my $log_actions = 0;
if ($args{'package'} ne 'RT') {
    RT->ConnectToDatabase();
    RT->InitSystemObjects();
    $log_actions = 1;
}

foreach my $action ( @actions ) {
    no strict 'refs';
    my ($status, $msg) = *{ 'action_'. $action }{'CODE'}->( %args );
    error($action, $msg) unless $status;
    print $msg .".\n" if $msg;
    print "Done.\n";
}

sub action_create {
    my %args = @_;
    my $dbh = get_system_dbh();
    my ($status, $msg) = RT::Handle->CheckCompatibility( $dbh, 'create' );
    return ($status, $msg) unless $status;

    print "Now creating a $db_type database $db_name for RT.\n";
    return RT::Handle->CreateDatabase( $dbh );
}

sub action_drop {
    my %args = @_;

    print "Dropping $db_type database $db_name.\n";
    unless ( $args{'force'} ) {
        print <<END;

About to drop $db_type database $db_name on $db_host (port '$db_port').
WARNING: This will erase all data in $db_name.

END
        exit(-2) unless _yesno();
    }

    my $dbh = get_system_dbh();
    return RT::Handle->DropDatabase( $dbh );
}

sub action_schema {
    my %args = @_;
    my $dbh = get_admin_dbh();
    my ($status, $msg) = RT::Handle->CheckCompatibility( $dbh, 'schema' );
    return ($status, $msg) unless $status;

    my $individual_id = Data::GUID->new->as_string();
    my %upgrade_data = (
        action   => 'schema',
        filename => Cwd::abs_path($args{'datafile'} || $args{'datadir'} || ''),
        stage    => 'before',
        full_id  => $full_id,
        individual_id => $individual_id,
    );
    $upgrade_data{'ext_version'} = $ext_version if $ext_version;
    RT->System->AddUpgradeHistory($package => \%upgrade_data) if $log_actions;

    print "Now populating database schema.\n";
    my @ret = RT::Handle->InsertSchema( $dbh, $args{'datafile'} || $args{'datadir'} );

    %upgrade_data = (
        stage         => 'after',
        individual_id => $individual_id,
        return_value  => [ @ret ],
    );
    RT->System->AddUpgradeHistory($package => \%upgrade_data) if $log_actions;

    return @ret;
}

sub action_acl {
    my %args = @_;
    my $dbh = get_admin_dbh();
    my ($status, $msg) = RT::Handle->CheckCompatibility( $dbh, 'acl' );
    return ($status, $msg) unless $status;

    my $individual_id = Data::GUID->new->as_string();
    my %upgrade_data = (
        action   => 'acl',
        filename => Cwd::abs_path($args{'datafile'} || $args{'datadir'} || ''),
        stage    => 'before',
        full_id  => $full_id,
        individual_id => $individual_id,
    );
    $upgrade_data{'ext_version'} = $ext_version if $ext_version;
    RT->System->AddUpgradeHistory($package => \%upgrade_data) if $log_actions;

    print "Now inserting database ACLs.\n";
    my @ret = RT::Handle->InsertACL( $dbh, $args{'datafile'} || $args{'datadir'} );

    %upgrade_data = (
        stage         => 'after',
        individual_id => $individual_id,
        return_value  => [ @ret ],
    );
    RT->System->AddUpgradeHistory($package => \%upgrade_data) if $log_actions;

    return @ret;
}

sub action_indexes {
    my %args = @_;
    RT->ConnectToDatabase;
    my $individual_id = Data::GUID->new->as_string();
    my %upgrade_data = (
        action   => 'indexes',
        filename => Cwd::abs_path($args{'datafile'} || $args{'datadir'} || ''),
        stage    => 'before',
        full_id  => $full_id,
        individual_id => $individual_id,
    );
    $upgrade_data{'ext_version'} = $ext_version if $ext_version;
    RT->System->AddUpgradeHistory($package => \%upgrade_data) if $log_actions;

    my $dbh = get_admin_dbh();
    $RT::Handle = RT::Handle->new;
    $RT::Handle->dbh( $dbh );
    RT::InitLogging();

    print "Now inserting database indexes.\n";
    my @ret = RT::Handle->InsertIndexes( $dbh, $args{'datafile'} || $args{'datadir'} );

    $RT::Handle = RT::Handle->new;
    $RT::Handle->dbh( undef );
    RT->ConnectToDatabase;
    %upgrade_data = (
        stage         => 'after',
        individual_id => $individual_id,
        return_value  => [ @ret ],
    );
    RT->System->AddUpgradeHistory($package => \%upgrade_data) if $log_actions;

    return @ret;
}

sub action_coredata {
    my %args = @_;
    $RT::Handle = RT::Handle->new;
    $RT::Handle->dbh( undef );
    RT::ConnectToDatabase();
    my ($status, $msg) = RT::Handle->CheckCompatibility( $RT::Handle->dbh, 'coredata' );
    return ($status, $msg) unless $status;

    print "Now inserting RT core system objects.\n";
    return $RT::Handle->InsertInitialData;
}

sub action_insert {
    state $RAN_INIT;
    my %args = @_;
    unless ($RAN_INIT) {
        $RT::Handle = RT::Handle->new;
        RT::Init();
        $RAN_INIT++;
    }
    $log_actions = 1;

    my ($status, $msg) = RT::Handle->CheckCompatibility( $RT::Handle->dbh, 'insert' );
    return ($status, $msg) unless $status;

    print "Now inserting data.\n";
    my $file = $args{'datafile'};
    $file = $RT::EtcPath . "/initialdata" if $init && !$file;
    $file ||= $args{'datadir'}."/content";

    my $individual_id = Data::GUID->new->as_string();
    my %upgrade_data = (
        action   => 'insert',
        filename => Cwd::abs_path($file),
        stage    => 'before',
        full_id  => $full_id,
        individual_id => $individual_id
    );
    $upgrade_data{'ext_version'} = $ext_version if $ext_version;

    open my $handle, '<', $file or warn "Unable to open $file: $!";
    $upgrade_data{content} = do {local $/; <$handle>} if $handle;

    RT->System->AddUpgradeHistory($package => \%upgrade_data);

    my @ret;

    my $upgrade = sub { @ret = $RT::Handle->InsertData( $file, $root_password ) };

    for my $file (@{$args{backcompat} || []}) {
        my $lines = do {local $/; local @ARGV = ($file); <>};
        my $sub = eval "sub {\n# line 1 $file\n$lines\n}";
        unless ($sub) {
            warn "Failed to load backcompat $file: $@";
            next;
        }
        my $current = $upgrade;
        $upgrade = sub { $sub->($current) };
    }

    $upgrade->();

    # XXX Reconnecting to insert the history entry
    # until we can sort out removing
    # the disconnect at the end of InsertData.
    RT->ConnectToDatabase();

    %upgrade_data = (
        stage         => 'after',
        individual_id => $individual_id,
        return_value  => [ @ret ],
    );

    RT->System->AddUpgradeHistory($package => \%upgrade_data);

    my $db_type = RT->Config->Get('DatabaseType');
    $RT::Handle->Disconnect() unless $db_type eq 'SQLite';

    return @ret;
}

sub action_upgrade {
    my %args = @_;
    my $base_dir = $args{'datadir'} || "./etc/upgrade";
    return (0, "Couldn't read dir '$base_dir' with upgrade data")
        unless -d $base_dir || -r _;

    my $upgrading_from = undef;
    do {
        if ( defined $upgrading_from ) {
            print "Doesn't match #.#.#: ";
        } else {
            print "Enter $args{package} version you're upgrading from: ";
        }
        $upgrading_from = $args{'upgrade-from'} || scalar <STDIN>;
        chomp $upgrading_from;
        $upgrading_from =~ s/\s+//g;
    } while $upgrading_from !~ /$version_dir/;

    my $upgrading_to = $RT::VERSION;
    return (0, "The current version $upgrading_to is lower than $upgrading_from")
        if RT::Handle::cmp_version( $upgrading_from, $upgrading_to ) > 0;

    return (1, "The version $upgrading_to you're upgrading to is up to date")
        if RT::Handle::cmp_version( $upgrading_from, $upgrading_to ) == 0;

    my @versions = get_versions_from_to($base_dir, $upgrading_from, undef);
    return (1, "No DB changes since $upgrading_from")
        unless @versions;

    if (RT::Handle::cmp_version($versions[-1], $upgrading_to) > 0) {
        print "\n***** There are upgrades for $versions[-1], which is later than $upgrading_to,\n";
        print   "***** which you are nominally upgrading to.  Upgrading to $versions[-1] instead.\n";
        $upgrading_to = $versions[-1];
    }

    print "\nGoing to apply following upgrades:\n";
    print map "* $_\n", @versions;

    {
        my $custom_upgrading_to = undef;
        do {
            if ( defined $custom_upgrading_to ) {
                print "Doesn't match #.#.#: ";
            } else {
                print "\nEnter $args{package} version if you want to stop upgrade at some point,\n";
                print "  or leave it blank if you want apply above upgrades: ";
            }
            $custom_upgrading_to = $args{'upgrade-to'} || scalar <STDIN>;
            chomp $custom_upgrading_to;
            $custom_upgrading_to =~ s/\s+//g;
            last unless $custom_upgrading_to;
        } while $custom_upgrading_to !~ /$version_dir/;

        if ( $custom_upgrading_to ) {
            return (
                0, "The version you entered ($custom_upgrading_to) is lower than\n"
                ."version you're upgrading from ($upgrading_from)"
            ) if RT::Handle::cmp_version( $upgrading_from, $custom_upgrading_to ) > 0;

            return (1, "The version you're upgrading to is up to date")
                if RT::Handle::cmp_version( $upgrading_from, $custom_upgrading_to ) == 0;

            if ( RT::Handle::cmp_version( $RT::VERSION, $custom_upgrading_to ) < 0 ) {
                print "Version you entered is greater than installed ($RT::VERSION).\n";
                _yesno() or exit(-2);
            }
            # ok, checked everything no let's refresh list
            $upgrading_to = $custom_upgrading_to;
            @versions = get_versions_from_to($base_dir, $upgrading_from, $upgrading_to);

            return (1, "No DB changes between $upgrading_from and $upgrading_to")
                unless @versions;

            print "\nGoing to apply following upgrades:\n";
            print map "* $_\n", @versions;
        }
    }

    unless ( $args{'force'} ) {
        print "\nIT'S VERY IMPORTANT TO BACK UP BEFORE THIS STEP\n\n";
        _yesno() or exit(-2);
    }

    RT->ConnectToDatabase();
    RT->InitSystemObjects();
    $log_actions = 1;

    RT->System->AddUpgradeHistory($package => {
        type      => 'full upgrade',
        action    => 'upgrade',
        stage     => 'before',
        from      => $upgrading_from,
        to        => $upgrading_to,
        versions  => [@versions],
        full_id => $full_id,
        individual_id => $full_id
    });

    # Ensure that the Attributes column is big enough to hold the
    # upgrade steps we're going to add; this step exists in 4.0.6 for
    # mysql, but that may be too late.  Run it as soon as possible.
    if (RT->Config->Get('DatabaseType') eq 'mysql'
            and RT::Handle::cmp_version( $upgrading_from, '4.0.6') < 0) {
        my $dbh = get_admin_dbh();
        # Before the binary switch in 3.7.87, we want to alter text ->
        # longtext, not blob -> longblob
        if (RT::Handle::cmp_version( $upgrading_from, '3.7.87') < 0) {
            $dbh->do("ALTER TABLE Attributes MODIFY Content LONGTEXT")
        } else {
            $dbh->do("ALTER TABLE Attributes MODIFY Content LONGBLOB")
        }
    }

    my $previous = $upgrading_from;
    my ( $ret, $msg );
    foreach my $n ( 0..$#versions ) {
        my $v = $versions[$n];
        my $individual_id = Data::GUID->new->as_string();

        my @back = grep {-e $_} map {"$base_dir/$versions[$_]/backcompat"} $n+1..$#versions;
        print "Processing $v\n";

        RT->System->AddUpgradeHistory($package => {
            action => 'upgrade',
            type   => 'individual upgrade',
            stage  => 'before',
            from   => $previous,
            to     => $v,
            full_id => $full_id,
            individual_id => $individual_id,
        });

        my %tmp = (%args, datadir => "$base_dir/$v", datafile => undef, backcompat => \@back);

        if ( -e "$base_dir/$v/schema.$db_type" ) {
            ( $ret, $msg ) = action_schema( %tmp );
            return ( $ret, $msg ) unless $ret;
        }
        if ( -e "$base_dir/$v/acl.$db_type" ) {
            ( $ret, $msg ) = action_acl( %tmp );
            return ( $ret, $msg ) unless $ret;
        }
        if ( -e "$base_dir/$v/indexes" ) {
            ( $ret, $msg ) = action_indexes( %tmp );
            return ( $ret, $msg ) unless $ret;
        }
        if ( -e "$base_dir/$v/content" ) {
            ( $ret, $msg ) = action_insert( %tmp );
            return ( $ret, $msg ) unless $ret;
        }

        # XXX: Another connect since the insert called
        # previous to this step will disconnect.

        RT->ConnectToDatabase();

        RT->System->AddUpgradeHistory($package => {
            stage         => 'after',
            individual_id => $individual_id,
        });

        $previous = $v;
    }

    RT->System->AddUpgradeHistory($package => {
        stage         => 'after',
        individual_id => $full_id,
    });

    return 1;
}

sub get_versions_from_to {
    my ($base_dir, $from, $to) = @_;

    opendir( my $dh, $base_dir ) or die "couldn't open dir: $!";
    my @versions = grep -d "$base_dir/$_" && /$version_dir/, readdir $dh;
    closedir $dh;

    die "\nERROR: No upgrade data found in '$base_dir'!  Perhaps you specified the wrong --datadir?\n"
        unless @versions;

    return
        grep defined $to ? RT::Handle::cmp_version($_, $to) <= 0 : 1,
        grep RT::Handle::cmp_version($_, $from) > 0,
        sort RT::Handle::cmp_version @versions;
}

sub error {
    my ($action, $msg) = @_;
    print STDERR "Couldn't finish '$action' step.\n\n";
    print STDERR "ERROR: $msg\n\n";
    exit(-1);
}

sub get_dba_password {
    print "In order to create or update your RT database,"
        . " this script needs to connect to your "
        . " $db_type instance on $db_host (port '$db_port') as $dba_user\n";
    print "Please specify that user's database password below. If the user has no database\n";
    print "password, just press return.\n\n";
    print "Password: ";
    ReadMode('noecho');
    my $password = ReadLine(0);
    ReadMode('normal');
    print "\n";
    return ($password);
}

#   get_system_dbh
#   Returns L<DBI> database handle connected to B<system> with DBA credentials.
#   See also L<RT::Handle/SystemDSN>.


sub get_system_dbh {
    return _get_dbh( RT::Handle->SystemDSN, $dba_user, $dba_pass );
}

sub get_admin_dbh {
    return _get_dbh( RT::Handle->DSN, $dba_user, $dba_pass );
}

# get_rt_dbh [USER, PASSWORD]

# Returns L<DBI> database handle connected to RT database,
# you may specify credentials(USER and PASSWORD) to connect
# with. By default connects with credentials from RT config.

sub get_rt_dbh {
    return _get_dbh( RT::Handle->DSN, $db_user, $db_pass );
}

sub _get_dbh {
    my ($dsn, $user, $pass) = @_;
    my $dbh = DBI->connect(
        $dsn, $user, $pass,
        { RaiseError => 0, PrintError => 0 },
    );
    unless ( $dbh ) {
        my $msg = "Failed to connect to $dsn as user '$user': ". $DBI::errstr;
        if ( $args{'debug'} ) {
            require Carp; Carp::confess( $msg );
        } else {
            print STDERR $msg; exit -1;
        }
    }
    return $dbh;
}

sub _yesno {
    print "Proceed [y/N]:";
    my $x = scalar(<STDIN>);
    $x =~ /^y/i;
}

1;

__END__

=head1 NAME

rt-setup-database - Set up RT's database

=head1 SYNOPSIS

    rt-setup-database --action ... 

=head1 OPTIONS

=over

=item action

Several actions can be combined using comma separated list.

=over

=item init

Initialize the database. This is combination of multiple actions listed below.
Create DB, schema, setup acl, insert core data and initial data.

=item upgrade

Apply all needed schema/acl/content updates (will ask for version to upgrade
from)

=item create

Create the database.

=item drop

Drop the database.  This will B<ERASE ALL YOUR DATA>.

=item schema

Initialize only the database schema

To use a local or supplementary datafile, specify it using the '--datadir'
option below.

=item acl

Initialize only the database ACLs

To use a local or supplementary datafile, specify it using the '--datadir'
option below.

=item coredata 

Insert data into RT's database. This data is required for normal functioning of
any RT instance.

=item insert

Insert data into RT's database.  By default, will use RT's installation data.
To use a local or supplementary datafile, specify it using the '--datafile'
option below.

=back

=item datafile

file path of the data you want to action on

e.g. C<--datafile /path/to/datafile>

=item datadir

Used to specify a path to find the local database schema and acls to be
installed.

e.g. C<--datadir /path/to/>

=item dba

dba's username

=item dba-password

dba's password

=item prompt-for-dba-password

Ask for the database administrator's password interactively

=item skip-create

for 'init': skip creating the database and the user account, so we don't need
administrator privileges

=item root-password-file

for 'init' and 'insert': rather than using the default administrative password
for RT's "root" user, use the password in this file.

=item package 

the name of the entity performing a create or upgrade. Used for logging changes
in the DB. Defaults to RT, otherwise it should be the fully qualified package name
of the extension or plugin making changes to the DB.

=item ext-version

current version of extension making a change. Not needed for RT since RT has a
more elaborate system to track upgrades across multiple versions.

=item upgrade-from

for 'upgrade': specifies the version to upgrade from, and do not prompt
for it if it appears to be a valid version.

=item upgrade-to

for 'upgrade': specifies the version to upgrade to, and do not prompt
for it if it appears to be a valid version.

=back

=cut
