using System.Text.Json;
using System.Text.Json.Serialization;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.AdminUI.Components.Pages.Clusters.Drivers;
using ZB.MOM.WW.OtOpcUa.Driver.Modbus;

namespace ZB.MOM.WW.OtOpcUa.AdminUI.Tests;

public sealed class ModbusDriverPageFormSerializationTests
{
    private static readonly JsonSerializerOptions _opts = new()
    {
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
        WriteIndented = false,
    };

    private static readonly JsonSerializerOptions TestJsonOpts = new()
    {
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
        UnmappedMemberHandling = JsonUnmappedMemberHandling.Skip,
    };

    [Fact]
    public void RoundTrip_PreservesKnownFields()
    {
        var original = new ModbusDriverOptions
        {
            Host = "10.0.0.42",
            Port = 5020,
            UnitId = 3,
            Timeout = TimeSpan.FromSeconds(5),
            MaxRegistersPerRead = 64,
            MaxRegistersPerWrite = 60,
            MaxCoilsPerRead = 500,
            MaxReadGap = 8,
            UseFC15ForSingleCoilWrites = true,
            UseFC16ForSingleRegisterWrites = true,
            DisableFC23 = true,
            WriteOnChangeOnly = true,
            AutoReconnect = false,
            Family = ModbusFamily.DL205,
            MelsecSubFamily = MelsecFamily.F_iQF,
            Probe = new ModbusProbeOptions
            {
                Enabled = false,
                Interval = TimeSpan.FromSeconds(10),
                Timeout = TimeSpan.FromSeconds(3),
                ProbeAddress = 7,
            },
            KeepAlive = new ModbusKeepAliveOptions
            {
                Enabled = false,
                Time = TimeSpan.FromSeconds(60),
                Interval = TimeSpan.FromSeconds(15),
                RetryCount = 5,
            },
            Reconnect = new ModbusReconnectOptions
            {
                InitialDelay = TimeSpan.FromSeconds(1),
                MaxDelay = TimeSpan.FromSeconds(60),
                BackoffMultiplier = 1.5,
            },
            ProbeTimeoutSeconds = 10,
        };

        var json = JsonSerializer.Serialize(original, _opts);
        var back = JsonSerializer.Deserialize<ModbusDriverOptions>(json, _opts);

        back.ShouldNotBeNull();
        back.Host.ShouldBe("10.0.0.42");
        back.Port.ShouldBe(5020);
        back.UnitId.ShouldBe((byte)3);
        back.Timeout.ShouldBe(TimeSpan.FromSeconds(5));
        back.MaxRegistersPerRead.ShouldBe((ushort)64);
        back.MaxRegistersPerWrite.ShouldBe((ushort)60);
        back.MaxCoilsPerRead.ShouldBe((ushort)500);
        back.MaxReadGap.ShouldBe((ushort)8);
        back.UseFC15ForSingleCoilWrites.ShouldBeTrue();
        back.UseFC16ForSingleRegisterWrites.ShouldBeTrue();
        back.DisableFC23.ShouldBeTrue();
        back.WriteOnChangeOnly.ShouldBeTrue();
        back.AutoReconnect.ShouldBeFalse();
        back.Family.ShouldBe(ModbusFamily.DL205);
        back.MelsecSubFamily.ShouldBe(MelsecFamily.F_iQF);
        back.Probe.Enabled.ShouldBeFalse();
        back.Probe.Interval.ShouldBe(TimeSpan.FromSeconds(10));
        back.Probe.Timeout.ShouldBe(TimeSpan.FromSeconds(3));
        back.Probe.ProbeAddress.ShouldBe((ushort)7);
        back.KeepAlive.Enabled.ShouldBeFalse();
        back.KeepAlive.Time.ShouldBe(TimeSpan.FromSeconds(60));
        back.KeepAlive.Interval.ShouldBe(TimeSpan.FromSeconds(15));
        back.KeepAlive.RetryCount.ShouldBe(5);
        back.Reconnect.InitialDelay.ShouldBe(TimeSpan.FromSeconds(1));
        back.Reconnect.MaxDelay.ShouldBe(TimeSpan.FromSeconds(60));
        back.Reconnect.BackoffMultiplier.ShouldBe(1.5);
        back.ProbeTimeoutSeconds.ShouldBe(10);
    }

    [Fact]
    public void Deserialize_DropsUnknownFields()
    {
        var jsonWithExtra = """{"unknownField":"old-value","probeTimeoutSeconds":10}""";

        var optsWithSkip = new JsonSerializerOptions(_opts)
        {
            UnmappedMemberHandling = JsonUnmappedMemberHandling.Skip,
        };

        var back = JsonSerializer.Deserialize<ModbusDriverOptions>(jsonWithExtra, optsWithSkip);
        back.ShouldNotBeNull();
        back.ProbeTimeoutSeconds.ShouldBe(10);
    }

    [Fact]
    public void TagRow_round_trips_through_definition()
    {
        var row = new ModbusDriverPage.ModbusTagRow
        {
            Name = "Pump1_Speed", Region = ModbusRegion.HoldingRegisters, Address = 40001,
            DataType = ModbusDataType.Int16, Writable = true,
        };
        var def = row.ToDefinition();
        var back = ModbusDriverPage.ModbusTagRow.FromDefinition(def);

        back.Name.ShouldBe("Pump1_Speed");
        back.Address.ShouldBe(40001);
        back.DataType.ShouldBe(ModbusDataType.Int16);
        back.Writable.ShouldBeTrue();
    }

    [Fact]
    public void Tag_list_survives_options_serialize_round_trip()
    {
        var tags = new List<ModbusTagDefinition>
        {
            new("A", ModbusRegion.HoldingRegisters, 1, ModbusDataType.Int16),
            new("B", ModbusRegion.Coils, 2, ModbusDataType.Bool),
        };
        var opts = new ModbusDriverPage.FormModel().ToOptions(tags);
        var json = JsonSerializer.Serialize(opts, TestJsonOpts);
        var back = JsonSerializer.Deserialize<ModbusDriverOptions>(json, TestJsonOpts)!;
        back.Tags.Count.ShouldBe(2);
        back.Tags[0].Name.ShouldBe("A");
    }

    [Fact]
    public void ValidateRow_rejects_duplicate_name()
    {
        var rows = new List<ModbusDriverPage.ModbusTagRow> { new() { Name = "A" } };
        ModbusDriverPage.ModbusTagRow.ValidateRow(new() { Name = "A" }, rows, null)
            .ShouldNotBeNull();
    }

    [Fact]
    public void ToDefinition_preserves_unedited_fields()
    {
        var original = new ModbusTagDefinition(
            "T", ModbusRegion.HoldingRegisters, 5, ModbusDataType.Int16,
            StringByteOrder: ModbusStringByteOrder.LowByteFirst,
            ArrayCount: 10, Deadband: 0.5, UnitId: 3, CoalesceProhibited: true);
        var row = ModbusDriverPage.ModbusTagRow.FromDefinition(original);
        row.Name = "Renamed";

        var back = row.ToDefinition();
        back.Name.ShouldBe("Renamed");
        back.UnitId.ShouldBe((byte)3);
        back.ArrayCount.ShouldBe(10);
        back.Deadband.ShouldBe(0.5);
        back.StringByteOrder.ShouldBe(ModbusStringByteOrder.LowByteFirst);
        back.CoalesceProhibited.ShouldBeTrue();
    }
}