#!/usr/bin/perl -w
###############################################################################
=pod

=head1 NAME

mig-init - This will add or recreate tracking tables for the B<mig> toolset to
the migration schema specified by the MIGSCHEMA environment variable, in the
PostgreSQL database specified by various PG environment variables.

In practice, you should invoke 'mig env use schema_name' prior to calling
B<init>

=head1 SYNOPSIS

B<mig-init>

B<mig-init> <help>

=cut

###############################################################################

use strict;
use Switch;
use Env qw(
    HOME PGHOST PGPORT PGUSER PGDATABASE MIGSCHEMA
    MIGBASEWORKDIR MIGBASEGITDIR MIGGITDIR MIGWORKDIR
);
use Pod::Usage;
use DBI;
use FindBin;
my $mig_bin = "$FindBin::Bin/";
use lib "$FindBin::Bin/";
use Mig;

pod2usage(-verbose => 2) if $ARGV[0];

Mig::die_if_no_env_migschema();

if (! Mig::check_for_db_migschema()) {
    try_to_create_schema();
}

if (! Mig::check_db_migschema_for_migration_tables()) {
    try_to_init_schema_with_migration_tools();
}
vivicate_mig_tracking_tables();

exit 0;

###############################################################################

sub try_to_create_schema {
    if ($MIGSCHEMA =~ /[^\w_]/) {
        die "$MIGSCHEMA is not suitable for a schema name in PostgreSQL\n";
    }
    my $dbh = Mig::db_connect();
    my $rv = $dbh->do("CREATE SCHEMA $MIGSCHEMA;")
        || die "Error creating migration schema ($MIGSCHEMA): $!\n";
    print "Created schema $MIGSCHEMA\n";
    Mig::db_disconnect($dbh);
}

sub try_to_init_schema_with_migration_tools {
    Mig::die_if_no_migration_tools();
    print "Calling migration_tools.init() and .build()\n";
    my $dbh = Mig::db_connect();
    my $rv = $dbh->do("SELECT migration_tools.init(" . $dbh->quote($MIGSCHEMA) . ");")
        || die "Error running migration_tools.init($MIGSCHEMA): $!\n";
    print "migration_tools.init() finished\n";
    my $rv2 = $dbh->do("SELECT migration_tools.build(" . $dbh->quote($MIGSCHEMA) . ");")
        || die "Error running migration_tools.build($MIGSCHEMA): $!\n";
    print "migration_tools.build() finished\n";
    Mig::db_disconnect($dbh);
}

sub vivicate_mig_tracking_tables {
    Mig::die_if_mig_tracking_table_exists();
    print "Creating table $MIGSCHEMA.tracked_file...\n";
    my $dbh = Mig::db_connect();
    my $rv = $dbh->do("
        CREATE TABLE $MIGSCHEMA.tracked_file (
             id                 serial
            ,base_filename      TEXT UNIQUE
            ,has_headers        BOOLEAN
            ,headers_file       TEXT
            ,utf8_filename      TEXT
            ,clean_filename     TEXT
            ,stage_sql_filename TEXT
            ,map_sql_filename   TEXT
            ,prod_sql_filename  TEXT
            ,parent_table       TEXT
            ,staged_table       TEXT
        );
    ") || die "Error creating table $MIGSCHEMA.tracked_file: $!\n";
    Mig::die_if_mig_column_tracking_table_exists();
    my $rv2 = $dbh->do("
        CREATE TABLE $MIGSCHEMA.tracked_column (
             id                 serial
            ,base_filename      TEXT
            ,parent_table       TEXT
            ,staged_table       TEXT
            ,staged_column      TEXT
            ,comment            TEXT
            ,target_table       TEXT
            ,target_column      TEXT
            ,transform          TEXT
            ,summarize          BOOLEAN
        );
    ") || die "Error creating table $MIGSCHEMA.tracked_column: $!\n";
    my $rv3 = $dbh->do("
        CREATE INDEX ON $MIGSCHEMA.tracked_column(target_table,target_column);
    ") || die "Error creating index on $MIGSCHEMA.tracked_column: $!\n";
    my $rv4 = $dbh->do("
        CREATE INDEX ON $MIGSCHEMA.tracked_column(base_filename);
    ") || die "Error creating index on $MIGSCHEMA.tracked_column: $!\n";
    Mig::db_disconnect($dbh);
}