using System;

using System.Linq;

using BenchmarkDotNet.Attributes;

namespace Npgsql.Benchmarks;

[OperationsPerSecond, PerElementMean]

public class GetFieldValue

{

readonly NpgsqlConnection _conn;

readonly NpgsqlCommand _cmd;

readonly NpgsqlDataReader _reader;

const int ArrayLength = 100;

public GetFieldValue()

{

_conn = BenchmarkEnvironment.OpenConnection();

var ints = string.Join(",", Enumerable.Range(0, ArrayLength));

var timestamps = string.Join(",", Enumerable.Range(0, ArrayLength)

.Select(i => $"'2026-01-01'::timestamp + interval '{i} days'"));

var strings = string.Join(",", Enumerable.Range(0, ArrayLength)

.Select(i => $"'some realistic text value #{i:0000}'"));

_cmd = new NpgsqlCommand(

"SELECT 0, 'str', " +

$"ARRAY[{ints}]::integer[], " +

$"ARRAY[{timestamps}], " +

$"ARRAY[{strings}]::text[]",

_conn);

_reader = _cmd.ExecuteReader();

_reader.Read();

}

[GlobalCleanup]

public void Cleanup()

{

_reader.Dispose();

_cmd.Dispose();

_conn.Dispose();

}

[Benchmark]

public void NullableField() => _reader.GetFieldValue<int?>(0);

[Benchmark]

public void ValueTypeField() => _reader.GetFieldValue<int>(0);

[Benchmark]

public void ReferenceTypeField() => _reader.GetFieldValue<string>(1);

[Benchmark]

public void ObjectField() => _reader.GetFieldValue<object>(1);

[Benchmark, PerElement(ArrayLength)]

public void IntArrayField() => _reader.GetFieldValue<int[]>(2);

[Benchmark, PerElement(ArrayLength)]

public void DateTimeArrayField() => _reader.GetFieldValue<DateTime[]>(3);

[Benchmark, PerElement(ArrayLength)]

public void StringArrayField() => _reader.GetFieldValue<string[]>(4);

}