package LIMS::Local::QueryLog;

{ # mst fix for failure to re-chmod files after rotation in absence of server restart:
    package Log::Dispatch::File;
    use Class::Method::Modifiers;
    after log_message => sub { delete $_[0]->{chmodded} } # safe to retain after LDF fixed
}

# TODO: see __PACKAGE__ensure_warn_handler_capture if using Apache FastCgiServer

use strict;

use Readonly;
Readonly::Array my @STATEMENTS
	=> ( qw/SELECT INSERT UPDATE DELETE SHOW/, 'Making method' );
Readonly::Array my @ENV_OK => qw(DEVEL_SERVER RDBO_DEBUG_ON);

our $SKIP_LOG_QUERY; # allow specific queries to be exempted from log files (eg user msgs)

$|++;

BEGIN {
	use vars qw($LogArgs $cfg $dispatcher $path_to_app $mode $db); # to make available to _warn()
	use POSIX qw(strftime);

	use IO::All;
    # use LIMS::DB; # only required by format_query() - not working yet
    use Data::Printer;
    use LIMS::Local::Utils;
    use LIMS::Local::Config;

    use Log::Dispatch;
    use Log::Dispatch::File;

    use Sub::Exporter -setup =>
        { exports => [ qw(set_querylog_args clear_querylog_args) ] };
    # create new Log::Dispatch::File object (needs to be inside BEGIN block):
    my $new_ldf = sub { Log::Dispatch::File->new(@_) };

    # $db  = LIMS::DB->new_or_cached; # only required by format_query() - not working yet
	$cfg = LIMS::Local::Config->instance;
	$path_to_app = $cfg->{path_to_app_root};

    $dispatcher = Log::Dispatch->new;

	# are we running under fastcgi (deployment) or lims_server (development) mode?
    $mode = $ENV{ROSEDB_DEVINIT} =~ /devinit_prod/
		? 'deployment' : 'development';

    { # debug level log for SELECT/SHOW queries (fixed filename, rotated file):
        # deployment file permission needs to be group-writable to allow cron user to rotate:
        my $permission = ( $mode eq 'deployment' ) ? 0660 : 0640;
		my %args = (
			name => 'queries',
			mode => 'append', # happens anyway if close_after_write set to 1
			filename  => "${path_to_app}/logs/${mode}.sql",
			min_level => 'debug',
			permissions => $permission,
            # required to force file to be created after rotation, forces append mode:
            close_after_write => ( $mode eq 'deployment' ), # not required otherwise
		);
		my $o = &$new_ldf(%args);
		$dispatcher->add($o);
	}

    { # info level log for UPDATE/INSERT/DELETE statements (deployment only)
        # production system = archived date-stamped file
	    my $today = LIMS::Local::Utils::today->ymd; # warn $today;
		my %args = (
			name => 'edits',
			mode => 'append', # happens anyway with close_after_write set to 1
			filename  => "${path_to_app}/logs/${today}.sql", # eg 2019-04-04.sql
			min_level => 'info',
			permissions => 0660, # to allow cron user to rotate
            # required to force file to be created after rotation, forces append mode:
            close_after_write => 1,
		);
		my $o = &$new_ldf(%args);
		$dispatcher->add($o);
    }

    $SIG{__WARN__} = \&_warn_handler;
}


sub set_querylog_args {
    $LogArgs = shift;
#    $LogArgs{username} = $username;
}

sub clear_log_args {
#    %LogArgs = ();
}

sub format_query { # TODO: needs more work
    my $str = shift;
    $str =~ s/\((.*)\)$//; # remove & capture vars at end of string
    my @bind = split /,\s*/, $1;
    my $query = Local::Utils::format_query($db, $str, @bind);
    # remove blank lines (lines without alphanumeric characters):
    $query = join "\n", grep { $_ =~ /\w+/ } split "\n", $query;
    return $query;
}

# need to call this from app per-request (eg in cgiapp_prerun) if using fastcgi
# in non-external mode - CGI::Fast calls FCGI which re-defines $SIG{__WARN__};
# doesn't cause the same problem when app run as FastCgiExternalServer process
sub ensure_warn_handler_capture { $SIG{__WARN__} = \&_warn_handler; }

sub _warn_handler {
    my $warn = shift || return; # warn $SKIP_LOG_QUERY;

    my $time_now = LIMS::Local::Utils::date_and_time_now;

    # my $divider = '-+-' x 10;
    # $warn =~ s/\s{2}(JOIN)/\n\t$1/g; # line-break & tab JOIN's
    my $msg = sub { # reading pid id & size kills print run (timeout):
#        sprintf "[%s] %s [%s|%s|%s]\n%s\n", # [time] user [centre, pid ID & size] query:
#            $time_now, uc $LogArgs->{user}, uc $cfg->{settings}{_centre},
#            $$, format_number(`ps -p $$ -o size=`+0), $warn;
        sprintf "[%s] %s [%s]\n%s\n", # [time] user [centre] query:
            $time_now,
            uc ( $LogArgs->{user} || 'unknown' ),
            uc $cfg->{settings}{_centre},
            # format_query($warn); # not quite there yet
            $warn;
    }; # CORE::warn(&$msg);

	unless ($SKIP_LOG_QUERY) { # warn 'here';
        if ( $mode eq 'deployment' ) { # split edits from select queries:
            if ( $warn =~ /^(INSERT|UPDATE|DELETE)/ ) { # ie db edits
                $dispatcher->log(level => 'info', message => &$msg); # warn 'here';
            }
            elsif ( $warn =~ /^SELECT|SHOW/ ) { # non-edits
                $dispatcher->log(level => 'debug', message => &$msg); # warn 'here';
            }
        }
        # development has single file for combined queries:
        elsif ( $warn =~ /^(INSERT|UPDATE|DELETE|SELECT|SHOW)/ ) {
            $dispatcher->log(level => 'debug', message => &$msg); # warn 'here';
        }
	}
#    open my $fh, '>>'.'/tmp/env.txt' or die $!;
#    while( my ($k,$v) = each %ENV ) {
#      print $fh "$k: $v\n";
#    }

    # don't want RDBO::Manager or SQL query statements in apache's error.log
    if ( grep { $warn =~ /\A$_/ } @STATEMENTS ) { # p %ENV;
		return 0 unless grep $ENV{$_}, @ENV_OK;
        # dump queries to stdout, unless configured to skip:
		CORE::warn($warn) unless $SKIP_LOG_QUERY;
	}
	else { CORE::warn($warn) } # warn everything else

	# dump process size info to stdout if devel server or rdbo_debug:
	if ( $warn !~ /^Making method/ ) { # && grep $ENV{$_}, @ENV_OK ) {
        # my $process_size = `ps -p $$ -o size=`+0;  # moved to 'else' Nov/2016
        if ( $ENV{FAST_CGI} ) {
            my $logfile = $path_to_app . '/logs/processes/' . $$ . '.csv'; # warn $logfile;
            # my $line = join ',', $time_now, $process_size;
            my $line = join ',', $time_now, 'warn:'.$warn; # eg will get here for script errs
            # io($logfile)->append($line, "\n"); # stopped logging Nov/2016
        }
        else {
            my $process_size = `ps -p $$ -o size=`+0;
            CORE::warn sprintf "* process-size=%s\n", $process_size;
		}
	}
}

=begin # FileRotate causes serious performance hit here
    $dispatcher->add(
        Log::Dispatch::FileRotate->new(
            name        => 'query',
            min_level   => 'debug',
            filename    => "$path_to_app_root/logs/sql.txt",
            permissions => 0666,
            mode        => 'append',
            DatePattern => 'yyyy-MM-dd', # every day # or size => 1, # operates in date or size mode
        )
    );
=cut

1;