using AyCode.Core.Compression;
using AyCode.Core.Serializers.Attributes;
using AyCode.Core.Serializers.Binaries;
using AyCode.Core.Tests.Serialization;   // DrainFromAsync extension (test-only, used by benchmark)
using AyCode.Core.Tests.TestModels;
using MemoryPack;
#if !AYCODE_NATIVEAOT
using MessagePack;
using MessagePack.Resolvers;
#endif
using Microsoft.Extensions.Options;
using System.Buffers;
using System.Diagnostics;
using System.IO.Pipelines;
using System.IO.Pipes;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Text;
using System.Text.Json;

using AyCode.Core.Serializers.Console.Benchmarks;

namespace AyCode.Core.Serializers.Console;

/// <summary>
/// Comprehensive benchmark application for all serializers.
/// Compares: AcBinary (all options), MemoryPack, MessagePack, Newtonsoft.Json, System.Text.Json
/// 
/// Usage:
///   dotnet run                    # Run all benchmarks
///   dotnet run -- quick           # Quick mode (fewer iterations)
///   dotnet run -- serialize       # Serialize only
///   dotnet run -- deserialize     # Deserialize only
/// </summary>
public static class Program
{
    // Configuration (constants, mutable state, attribute-flag aggregation) → Configuration.cs
    // BuildAcBinary + GetMemPack helpers → Benchmarks/BenchmarkOptions.cs

    public static void Main(string[] args)
    {
        // Set console encoding to UTF-8 for proper Unicode character display
        System.Console.OutputEncoding = Encoding.UTF8;

        // Setup validation — abort BEFORE any benchmark logic if MemoryPack baseline is invalid.
        // Done early so user is told immediately, not after warmup.
        BenchmarkLoop.ValidateMemoryPackSetup();

        // CLI mode (args provided): run once, parse args, exit. Backward-compatible behaviour.
        if (args.Length > 0)
        {
            if (!TryParseCliArgs(args, out var layer, out var opMode, out var serializerMode))
                return;  // invalid args

            BenchmarkLoop.RunBenchmark(layer, opMode, serializerMode);
            return;
        }

        // Interactive mode (no args): loop the menu so the user doesn't have to restart between runs.
        // Q exits the menu (and the application).
        while (true)
        {
            var selection = Menu.ShowInteractiveMenu();
            if (selection == null) return;  // user pressed Q

            BenchmarkLoop.RunBenchmark(selection.Value.layer, BenchmarkOpMode.All, selection.Value.serializerMode);

            System.Console.WriteLine();
            System.Console.WriteLine("─────────────────────────────────────────────────────────────────────");
            System.Console.WriteLine("Returning to menu — press any key to continue, or Q to quit...");
            var key = System.Console.ReadKey(intercept: true);
            if (key.Key == ConsoleKey.Q) return;
            System.Console.WriteLine();
        }
    }

    /// <summary>
    /// Parses CLI arguments into (layer, opMode, serializerMode). Uses <see cref="Enum.TryParse{T}(string, bool, out T)"/>
    /// case-insensitive against the three enums in this order: <see cref="SerializerSelectionMode"/> (matches
    /// "FastestByte"/"AsyncPipe"), <see cref="BenchmarkOpMode"/> (matches "Serialize"/"Deserialize"), then
    /// <see cref="BenchmarkLayer"/> (matches "Core"/"Comprehensive"/"Edge"/"Small"/...). Special-cased:
    /// <c>"quick"</c> mutates <see cref="Configuration"/> warmup/iter counts but selects no layer/op/mode.
    /// Unknown args silently default to (All, All, Standard) — matches the prior behavior where unrecognized
    /// args fell through <see cref="BenchmarkLoop.FilterByLayer"/>'s default branch (full unfiltered suite).
    /// Returns <c>false</c> only if the caller-side path would need to abort; currently always returns <c>true</c>.
    /// </summary>
    private static bool TryParseCliArgs(string[] args, out BenchmarkLayer layer, out BenchmarkOpMode opMode, out SerializerSelectionMode serializerMode)
    {
        layer = BenchmarkLayer.All;
        opMode = BenchmarkOpMode.All;
        serializerMode = SerializerSelectionMode.Standard;

        var arg = args[0];

        // Quick mode: short warmup, few iterations, small sample count. Not an enum value — it's a
        // Configuration meta-flag, so handle it before the enum-parse cascade.
        if (string.Equals(arg, "quick", StringComparison.OrdinalIgnoreCase))
        {
            Configuration.WarmupIterations = 5;
            Configuration.TestIterations = 100;
            Configuration.BenchmarkSamples = 3;
            return true;
        }

        // Serializer-selection first (AsyncPipe/FastestByte/Standard) — narrower set than layers,
        // and "AsyncPipe" forced layer=All in the old code anyway.
        if (Enum.TryParse<SerializerSelectionMode>(arg, ignoreCase: true, out var sm))
        {
            serializerMode = sm;
            return true;
        }

        // Op-mode (Serialize/Deserialize/All).
        if (Enum.TryParse<BenchmarkOpMode>(arg, ignoreCase: true, out var om))
        {
            opMode = om;
            return true;
        }

        // Layer (Core/Comprehensive/Edge/Small/Medium/Large/Repeated/Deep/All).
        if (Enum.TryParse<BenchmarkLayer>(arg, ignoreCase: true, out var ly))
        {
            layer = ly;
            return true;
        }

        // Unknown arg — defaults remain (All, All, Standard). Matches prior behaviour where the
        // unrecognized string fell through FilterByLayer's `_ => all.ToList()` default branch.
        System.Console.Error.WriteLine($"Warning: unrecognized argument '{arg}'. Running full suite (Layer=All, OpMode=All, SerializerMode=Standard).");
        return true;
    }

    // RunBenchmark + RunBenchmarksForTestData + CreateSerializers → BenchmarkLoop.cs

    // Serializer implementations (ISerializerBenchmark + 12 concrete benchmark classes) → Benchmarks/

    // Results / output formatters → Output.cs
    // BenchmarkResult DTO → BenchmarkResult.cs

}