using System.IO;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Engines;
using ParadoxSaveParser.Lib;

namespace ParadoxSaveParser.Benchmarks;

/// <summary>
///     SearchExpression only, parsing straight from the save file on disk:
///     the file is opened inside the benchmark and is never preloaded into a byte[].
///     Run it once with and once without the internal <c>MemoryStream</c> copy in
///     <see cref="SaveParserEU4" /> to see what that copy buys.
/// </summary>
[MemoryDiagnoser]
[SimpleJob(RunStrategy.Monitoring, launchCount: 1, warmupCount: 1, iterationCount: 5)]
public class ParserInputBenchmarks
{
    private ISearchExpression _query = null!;

    [GlobalSetup]
    public void Setup() => _query = SearchExpressionCompiler.Compile(BenchData.PdxQuery);

    [Benchmark(Description = "SearchExpression over FileStream")]
    public long FromFile()
    {
        using var file = File.OpenRead(BenchData.PdxPath);
        return Extractors.SearchExpressionFromStream(file, _query);
    }
}