#!/usr/bin/perl

use strict;
use warnings;
use File::Basename;
use Text::Trim qw(trim);
use Test::More;
use lib 't';
use pgsm;

# Get filename and create out file name and dirs where requried
PGSM::setup_files_dir(basename($0));

# Create new PostgreSQL node and do initdb
my $node = PGSM->pgsm_init_pg();

my $run_pg_sleep_function_sql =
  "CREATE FUNCTION run_pg_sleep(loops int) RETURNS void AS \$\$
DECLARE
    iterator real := 0.002; -- we can init with 2 ms at declaration time
BEGIN
    WHILE iterator < loops LOOP
        RAISE INFO 'Current timestamp: %', timeofday()::timestamp;
        RAISE INFO 'Sleep % seconds', iterator;
        PERFORM pg_sleep(iterator);
        iterator := iterator + iterator;
    END LOOP;
END;
\$\$ LANGUAGE plpgsql;";

my $generate_histogram_function_sql = "CREATE FUNCTION generate_histogram()
    RETURNS TABLE (range text, freq int, bar text) AS \$\$
DECLARE
    bucket_id int;
    query_id bigint;
BEGIN
    SELECT bucket INTO bucket_id FROM pg_stat_monitor ORDER BY calls DESC LIMIT 1;
    SELECT queryid INTO query_id FROM pg_stat_monitor ORDER BY calls DESC LIMIT 1;
    RETURN QUERY SELECT * FROM histogram(bucket_id, query_id) AS a (range text, freq int, bar text);
END;
\$\$ LANGUAGE plpgsql;";

sub generate_histogram_with_configurations
{
	my ($h_min, $h_max, $h_buckets, $expected_calls_count,
		$expected_resp_calls, $expected_histogram_rows, $use_pg_sleep,
		$scenario_number)
	  = @_;

	PGSM::append_to_debug_file(
		"\n\n===============Scenario $scenario_number - Start==============="
	);

	PGSM::append_to_debug_file("pgsm_histogram_min : " . $h_min);
	PGSM::append_to_debug_file("pgsm_histogram_max : " . $h_max);
	PGSM::append_to_debug_file("pgsm_histogram_buckets : " . $h_buckets);
	PGSM::append_to_debug_file(
		"expected total calls count : " . $expected_calls_count);
	PGSM::append_to_debug_file(
		"expected resp_calls value : " . $expected_resp_calls);
	PGSM::append_to_debug_file("expected ranges (rows) count in histogram: "
		  . $expected_histogram_rows);
	PGSM::append_to_debug_file(
		"using pg_sleep to generate dataset : " . $use_pg_sleep);
	PGSM::append_to_debug_file("scenario number : " . $scenario_number);

	$node->append_conf('postgresql.conf',
		"pg_stat_monitor.pgsm_histogram_min = $h_min");
	$node->append_conf('postgresql.conf',
		"pg_stat_monitor.pgsm_histogram_max = $h_max");
	$node->append_conf('postgresql.conf',
		"pg_stat_monitor.pgsm_histogram_buckets = $h_buckets");
	$node->restart();

	my ($cmdret, $stdout, $stderr) = $node->psql(
		'postgres',
		"SELECT name, setting, unit, context, vartype, source, min_val, max_val, enumvals, boot_val, reset_val, pending_restart FROM pg_settings WHERE name LIKE 'pg_stat_monitor%histogram%';",
		extra_params => [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]);
	is($cmdret, 0,
		"Scenario $scenario_number : Print PGSM EXTENSION Settings");
	PGSM::append_to_debug_file($stdout);

	($cmdret, $stdout, $stderr) = $node->psql(
		'postgres',
		'SELECT pg_stat_monitor_reset();',
		extra_params => [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]);
	is($cmdret, 0, "Scenario $scenario_number : Reset PGSM Extension");
	PGSM::append_to_debug_file($stdout);

	if ($use_pg_sleep == 1)
	{
		($cmdret, $stdout, $stderr) = $node->psql(
			'postgres',
			'SELECT run_pg_sleep(10);',
			extra_params => [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]
		);
		is($cmdret, 0,
			"Scenario $scenario_number : Run run_pg_sleep(10) to generate data for histogram testing"
		);
		PGSM::append_to_debug_file($stdout);
	}
	else
	{
		for (my $count = 1; $count <= $expected_calls_count; $count++)
		{
			($cmdret, $stdout, $stderr) = $node->psql(
				'postgres',
				'SELECT 1 AS a;',
				extra_params =>
				  [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]);
			is($cmdret, 0, "Scenario $scenario_number : SELECT 1 AS a");
			PGSM::append_to_debug_file($stdout);
		}
	}

	($cmdret, $stdout, $stderr) = $node->psql(
		'postgres',
		'SELECT bucket, queryid, query, calls, resp_calls FROM pg_stat_monitor ORDER BY calls DESC;',
		extra_params => [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]);
	is($cmdret, 0,
		"Scenario $scenario_number : Print what is in pg_stat_monitor view");
	PGSM::append_to_debug_file($stdout);

	($cmdret, $stdout, $stderr) = $node->psql('postgres',
		'SELECT calls FROM pg_stat_monitor ORDER BY calls DESC LIMIT 1;');
	is($cmdret, 0, "Scenario $scenario_number : Get calls into a variable");
	is($stdout, $expected_calls_count,
		"Scenario $scenario_number : Calls are $expected_calls_count");
	my $calls_count = trim($stdout);
	PGSM::append_to_debug_file(
		"Scenario $scenario_number : Got Calls from query : " . $stdout);

	($cmdret, $stdout, $stderr) = $node->psql('postgres',
		'SELECT resp_calls FROM pg_stat_monitor ORDER BY calls DESC LIMIT 1;'
	);
	is($cmdret, 0,
		"Scenario $scenario_number : Get resp_calls into a variable");
	is(trim($stdout), "$expected_resp_calls",
		"Scenario $scenario_number : resp_calls is $expected_resp_calls");
	my $resp_calls = trim($stdout);
	PGSM::append_to_debug_file(
		"Scenario $scenario_number : Got resp_calls from query : " . $stdout);

	($cmdret, $stdout, $stderr) = $node->psql(
		'postgres',
		'SELECT * FROM generate_histogram();',
		extra_params => [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]);
	is($cmdret, 0,
		"Scenario $scenario_number : Generate Histogram for SELECT 1");
	PGSM::append_to_debug_file($stdout);
	like(
		$stdout,
		qr/$expected_histogram_rows rows/,
		"Scenario $scenario_number : $expected_histogram_rows rows are present in histogram output"
	);

	PGSM::append_to_debug_file("===============End===============");
}

$node->append_conf(
	'postgresql.conf', qq(
shared_preload_libraries = 'pg_stat_monitor'
pg_stat_monitor.pgsm_bucket_time = 36000
pg_stat_monitor.pgsm_normalized_query = on
pg_stat_monitor.pgsm_track = 'all'
));

# Start server
$node->start;

# Create functions required for testing
my ($cmdret, $stdout, $stderr) =
  $node->psql('postgres', "$run_pg_sleep_function_sql",
	extra_params => ['-a']);
is($cmdret, 0, "Create run_pg_sleep(int) function");
PGSM::append_to_debug_file($stdout);

($cmdret, $stdout, $stderr) = $node->psql(
	'postgres',
	"$generate_histogram_function_sql",
	extra_params => ['-a']);
is($cmdret, 0, "Create generate_histogram() function");
PGSM::append_to_debug_file($stdout);

# Create extension and change out file permissions
($cmdret, $stdout, $stderr) = $node->psql(
	'postgres',
	'CREATE EXTENSION pg_stat_monitor;',
	extra_params => ['-a']);
is($cmdret, 0, "Create PGSM Extension");
PGSM::append_to_debug_file($stdout);

# Following parameters are required for function 'generate_histogram_with_configurations' to generate and test a histogram
# with given configuration.
# Parameter 1 ==> pgsm_histogram_min
# Parameter 2 ==> pgsm_histogram_max
# Parameter 3 ==> pgsm_histogram_buckets
# Parameter 4 ==> generated and expected total calls count against 'SELECT 1 AS a'
# Parameter 5 ==> expected resp_calls value output
# Parameter 6 ==> expected ranges (rows) count in histogram output
# Parameter 7 ==> using pg_sleep to generate dataset, '1' will call sql function 'run_pg_sleep' (declared above).
#                 '0' will call the 'SELECT 1 AS a' expected_total_calls (Parameter 4) times.
# Parameter 8 ==> Scenario number (placeholder to reflect in log for debugging purposes)

# Scenario 1. Run pg_sleep
generate_histogram_with_configurations(1, 10000, 3, 13, "{0,4,4,5,0}", 5, 1,
	1);

#Scenario 2
generate_histogram_with_configurations(20, 40, 20, 2,
	"{2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}",
	22, 0, 2);

#Scenario 3
generate_histogram_with_configurations(1000, 1010, 6, 2, "{2,0,0,0,0,0,0,0}",
	8, 0, 3);

($cmdret, $stdout, $stderr) = $node->psql(
	'postgres',
	'SELECT * FROM generate_histogram();',
	extra_params => [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]);

like(
	$stdout,
	qr/\(1010\.000 - \.\.\.}}/,
	'final bucket goes from max to infinity');

#Scenario 4
generate_histogram_with_configurations(1, 10, 3, 2, "{2,0,0,0,0}", 5, 0, 4);

#Scenario 5
generate_histogram_with_configurations(0, 2, 2, 2, "{2,0,0}", 3, 0, 5);

#Scenario 6
generate_histogram_with_configurations(1, 2147483647, 20, 2,
	"{2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}",
	22, 0, 6);

#Scenario 7
generate_histogram_with_configurations(0, 2147483647, 20, 2,
	"{2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}",
	21, 0, 7);

#Scenario 8
generate_histogram_with_configurations(0, 50000000, 20, 2,
	"{2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}",
	20, 0, 8);

($cmdret, $stdout, $stderr) = $node->psql(
	'postgres',
	'SELECT * FROM generate_histogram();',
	extra_params => [ '-a', '-Pformat=aligned', '-Ptuples_only=off' ]);

like($stdout, qr/\(20607319\.480 - \.\.\.}}/,
	'final bucket goes to infinity');

#Scenario 9
generate_histogram_with_configurations(-1, 2147483648, 20, 2,
	"{2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}",
	22, 0, 9);

#Scenario 10
generate_histogram_with_configurations(-1, 2147483648, 20, 2,
	"{2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}",
	22, 0, 10);

#Scenario 11
generate_histogram_with_configurations(0, 49999999, 20, 2,
	"{2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}",
	21, 0, 11);

# Stop the server
$node->stop;

# Done testing for this testcase file.
done_testing();