using AyCode.Core.Serializers.Binaries;
using System.Collections;
using System.Reflection;
using System.Runtime.CompilerServices;

namespace AyCode.Core.Tests.TestModels;

public static class BenchmarkTestDataProvider
{
    private const int FixStrMaxLength = 31;
    private const string LongStringSuffix = "__Benchmárk_Long_String_Söffix__";

    private sealed class ReferenceComparer : IEqualityComparer<object>
    {
        public static readonly ReferenceComparer Instance = new();
        public new bool Equals(object? x, object? y) => ReferenceEquals(x, y);
        public int GetHashCode(object obj) => RuntimeHelpers.GetHashCode(obj);
    }

    public static List<TestDataSet> CreateTestDataSets(bool resetId = true)
    {
        return new List<TestDataSet>
        {
            CreateSmallTestData(resetId),
            CreateMediumTestData(resetId),
            CreateLargeTestData(resetId),
            CreateRepeatedStringsTestData(resetId),
            CreateDeepNestedTestData(resetId)
        };
    }

    public static TestOrder CreateProfilerOrder()
    {
        TestDataFactory.ResetIdCounter();
        var sharedTag = TestDataFactory.CreateTag("KözösCímke");
        var sharedUser = TestDataFactory.CreateUser("közösfelhasználó");
        return TestDataFactory.CreateOrder(
            itemCount: 3,
            palletsPerItem: 3,
            measurementsPerPallet: 3,
            pointsPerMeasurement: 4,
            sharedTag: sharedTag,
            sharedUser: sharedUser);
    }

    private static TestDataSet CreateSmallTestData(bool resetId = true)
    {
        if (resetId) TestDataFactory.ResetIdCounter();

        var sharedTag = TestDataFactory.CreateTag("KözösCímke");
        var sharedUser = TestDataFactory.CreateUser("közösfelhasználó");

        var order = TestDataFactory.CreateOrder(
            itemCount: 2,
            palletsPerItem: 2,
            measurementsPerPallet: 2,
            pointsPerMeasurement: 2,
            sharedTag: sharedTag,
            sharedUser: sharedUser);

        EnsureAllStringsBypassFixStr(order);

        ClearDeepLevelRefs(order);

        return new TestDataSet("Small (2x2x2x2)", order, iidRefPercent: 20);
    }

    private static TestDataSet CreateMediumTestData(bool resetId = true)
    {
        if (resetId) TestDataFactory.ResetIdCounter();

        var sharedTag = TestDataFactory.CreateTag("KözösCímke");
        var sharedUser = TestDataFactory.CreateUser("közösfelhasználó");
        var sharedMeta = TestDataFactory.CreateMetadata("közös", withChild: true);

        var sharedPreferences = new UserPreferences
        {
            Theme = "sötét",
            Language = "magyar",
            NotificationsEnabled = true,
            EmailDigestFrequency = "hetenkénti"
        };
        sharedUser.Preferences = sharedPreferences;

        var order = TestDataFactory.CreateOrder(
            itemCount: 3,
            palletsPerItem: 3,
            measurementsPerPallet: 3,
            pointsPerMeasurement: 4,
            sharedTag: sharedTag,
            sharedUser: sharedUser,
            sharedMetadata: sharedMeta,
            sharedPreferences: sharedPreferences);

        EnsureAllStringsBypassFixStr(order);

        ClearDeepLevelRefs(order);

        return new TestDataSet("Medium (3x3x3x4)", order, iidRefPercent: 20);
    }

    private static TestDataSet CreateLargeTestData(bool resetId = true)
    {
        if (resetId) TestDataFactory.ResetIdCounter();

        var sharedTag = TestDataFactory.CreateTag("KözösCímke");
        var sharedUser = TestDataFactory.CreateUser("közösfelhasználó");

        var sharedPreferences = new UserPreferences
        {
            Theme = "világos",
            Language = "német",
            NotificationsEnabled = false,
            EmailDigestFrequency = "naponkénti"
        };
        sharedUser.Preferences = sharedPreferences;

        var order = TestDataFactory.CreateOrder(
            itemCount: 5,
            palletsPerItem: 5,
            measurementsPerPallet: 5,
            pointsPerMeasurement: 10,
            sharedTag: sharedTag,
            sharedUser: sharedUser,
            sharedPreferences: sharedPreferences);

        EnsureAllStringsBypassFixStr(order);

        ClearDeepLevelRefs(order);

        return new TestDataSet("Large (5x5x5x10)", order, iidRefPercent: 20);
    }

    private static TestDataSet CreateRepeatedStringsTestData(bool resetId = true)
    {
        if (resetId) TestDataFactory.ResetIdCounter();

        var sharedTag = TestDataFactory.CreateTag("IsmétlődőCímke");
        var sharedUser = TestDataFactory.CreateUser("ismétlődőfelhasználó");

        var sharedPreferences = new UserPreferences
        {
            Theme = "sötét",
            Language = "magyar",
            NotificationsEnabled = true,
            EmailDigestFrequency = "hetenkénti"
        };
        sharedUser.Preferences = sharedPreferences;

        var order = TestDataFactory.CreateOrder(
            itemCount: 10,
            palletsPerItem: 2,
            measurementsPerPallet: 2,
            pointsPerMeasurement: 2,
            sharedTag: sharedTag,
            sharedUser: sharedUser,
            sharedPreferences: sharedPreferences);

        // Repeated string fields — ProductName on items + PalletCode on pallets. Both are common
        // across the hierarchy, exercising string-interning deduplication on the Default preset
        // (which has UseStringInterning = All). Targeting ~20% repeated-string share overall.
        // Strings contain non-ASCII characters (Hungarian accented letters → multi-byte UTF-8) so the
        // benchmark reflects real-world i18n payloads, not just the ASCII FixStr fast-path.
        foreach (var item in order.Items)
        {
            item.Status = TestStatus.Processing;
            item.ProductName = "TermékNév_IsmétlődőTesztAdat_árvíztűrőtükörfúrógép";

            foreach (var pallet in item.Pallets)
            {
                pallet.PalletCode = "RaklapKód_IsmétlődőTesztAdat_árvíztűrő";
            }
        }

        EnsureAllStringsBypassFixStr(order);

        ClearDeepLevelRefs(order);

        return new TestDataSet("Repeated Strings (10 items)", order, iidRefPercent: 20);
    }

    private static TestDataSet CreateDeepNestedTestData(bool resetId = true)
    {
        if (resetId) TestDataFactory.ResetIdCounter();

        var sharedTag = TestDataFactory.CreateTag("MélyCímke");
        var sharedUser = TestDataFactory.CreateUser("mélyfelhasználó");
        var sharedCategory = TestDataFactory.CreateCategory("MélyKategória");

        var sharedPreferences = new UserPreferences
        {
            Theme = "világos",
            Language = "francia",
            NotificationsEnabled = false,
            EmailDigestFrequency = "havonkénti"
        };
        sharedUser.Preferences = sharedPreferences;

        var order = TestDataFactory.CreateOrder(
            itemCount: 2,
            palletsPerItem: 4,
            measurementsPerPallet: 4,
            pointsPerMeasurement: 8,
            sharedTag: sharedTag,
            sharedUser: sharedUser,
            sharedPreferences: sharedPreferences,
            sharedCategory: sharedCategory);

        EnsureAllStringsBypassFixStr(order);

        ClearDeepLevelRefs(order);

        return new TestDataSet("Deep Nested (2x4x4x8)", order, iidRefPercent: 20);
    }

    private static void ClearDeepLevelRefs(TestOrder order)
    {
        // Keep shared IId refs at the pallet level (Tag + Inspector) — these contribute the bulk of
        // the ~20% IId-ref share that the test data targets. Only Category is cleared at this level
        // (one-of-three clears keep the share moderate). The deeper measurement / point levels are
        // cleared entirely so deep-tree ref noise does not skew the share upward beyond ~20%.
        foreach (var item in order.Items)
        {
            foreach (var pallet in item.Pallets)
            {
                // pallet.Tag = null;       // KEEP for ~20% IId-ref share (was cleared)
                // pallet.Inspector = null; // KEEP for ~20% IId-ref share (was cleared)
                pallet.Category = null;

                foreach (var measurement in pallet.Measurements)
                {
                    measurement.Tag = null;
                    measurement.Operator = null;

                    foreach (var point in measurement.Points)
                    {
                        point.Tag = null;
                        point.Verifier = null;
                    }
                }
            }
        }
    }

    private static void EnsureAllStringsBypassFixStr(object? root)
    {
        if (root == null) return;

        var visited = new HashSet<object>(ReferenceComparer.Instance);
        var stack = new Stack<object>();
        stack.Push(root);

        while (stack.Count > 0)
        {
            var current = stack.Pop();
            if (!visited.Add(current)) continue;

            if (current is IEnumerable enumerable && current is not string)
            {
                foreach (var item in enumerable)
                {
                    if (item != null)
                        stack.Push(item);
                }
                continue;
            }

            var type = current.GetType();
            foreach (var property in type.GetProperties(BindingFlags.Instance | BindingFlags.Public))
            {
                if (!property.CanRead) continue;

                if (property.PropertyType == typeof(string))
                {
                    if (!property.CanWrite) continue;

                    var value = (string?)property.GetValue(current);
                    property.SetValue(current, ToLongString(value));
                    continue;
                }

                if (property.PropertyType.IsValueType || property.PropertyType.IsEnum)
                    continue;

                var child = property.GetValue(current);
                if (child != null)
                    stack.Push(child);
            }
        }
    }

    [MethodImpl(MethodImplOptions.AggressiveInlining)]
    private static string ToLongString(string? value)
    {
        if (string.IsNullOrEmpty(value))
            return "Benchmark_String_Value" + LongStringSuffix;

        if (value.Length > FixStrMaxLength)
            return value;

        return value + LongStringSuffix;
    }
}

public sealed class TestDataSet
{
    public string Name { get; }
    public TestOrder Order { get; }

    /// <summary>
    /// Percentage of IId shared references in the data (0-100).
    /// Higher values mean more deduplication benefit for Default mode.
    /// </summary>
    public int IIdRefPercent { get; }

    public TestDataSet(string name, TestOrder order, int iidRefPercent = 0)
    {
        Name = name;
        Order = order;
        IIdRefPercent = iidRefPercent;
    }

    public string TypeName => Order.GetType().Name;

    /// <summary>
    /// Gets display name including IId ref percentage if set.
    /// </summary>
    public string DisplayName => IIdRefPercent > 0
        ? $"{Name} [{IIdRefPercent}% IId refs]"
        : Name;
}