using System.Text.Json;
using System.Text.Json.Serialization;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.AdminUI.Components.Shared.Drivers.Forms;
using ZB.MOM.WW.OtOpcUa.Driver.AbCip;

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

public sealed class AbCipDriverPageFormSerializationTests
{
    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 AbCipDriverOptions
        {
            Timeout = TimeSpan.FromSeconds(5),
            EnableControllerBrowse = true,
            EnableAlarmProjection = true,
            AlarmPollInterval = TimeSpan.FromSeconds(2),
            EnableDeclarationOnlyUdtGrouping = true,
            Probe = new AbCipProbeOptions
            {
                Enabled = true,
                Interval = TimeSpan.FromSeconds(10),
                Timeout = TimeSpan.FromSeconds(3),
                ProbeTagPath = "Program:Main.HealthBit",
            },
            ProbeTimeoutSeconds = 10,
            Devices =
            [
                new AbCipDeviceOptions("ab://10.0.0.1/1,0", AbCipPlcFamily.ControlLogix, "PLC-1"),
            ],
        };

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

        back.ShouldNotBeNull();
        back.Timeout.ShouldBe(TimeSpan.FromSeconds(5));
        back.EnableControllerBrowse.ShouldBeTrue();
        back.EnableAlarmProjection.ShouldBeTrue();
        back.AlarmPollInterval.ShouldBe(TimeSpan.FromSeconds(2));
        back.EnableDeclarationOnlyUdtGrouping.ShouldBeTrue();
        back.Probe.Enabled.ShouldBeTrue();
        back.Probe.Interval.ShouldBe(TimeSpan.FromSeconds(10));
        back.Probe.Timeout.ShouldBe(TimeSpan.FromSeconds(3));
        back.Probe.ProbeTagPath.ShouldBe("Program:Main.HealthBit");
        back.ProbeTimeoutSeconds.ShouldBe(10);
        back.Devices.Count.ShouldBe(1);
        back.Devices[0].HostAddress.ShouldBe("ab://10.0.0.1/1,0");
        back.Devices[0].PlcFamily.ShouldBe(AbCipPlcFamily.ControlLogix);
    }

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

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

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

    // v3 Batch-2 (WP3): the embedded-Devices CollectionEditor + AbCipDeviceRow retired — devices are now
    // separate Device entities authored via the raw-tree DeviceModal (AbCipDeviceModel, HostAddress/PlcFamily
    // into DeviceConfig). The former DeviceRow_* / ValidateDeviceRow_* tests were removed. The channel-config
    // FormModel now lives in AbCipDriverForm; the multi-device Devices array it preserves is covered below.

    [Fact]
    public void Device_list_survives_form_serialize_round_trip()
    {
        var devices = new List<AbCipDeviceOptions>
        {
            new("ab://10.0.0.1/1,0", AbCipPlcFamily.ControlLogix, "PLC-1"),
            new("ab://10.0.0.2/1,0", AbCipPlcFamily.CompactLogix, "PLC-2"),
        };
        var opts = new AbCipDriverForm.FormModel().ToOptions(devices);
        var json = JsonSerializer.Serialize(opts, TestJsonOpts);
        var back = JsonSerializer.Deserialize<AbCipDriverOptions>(json, TestJsonOpts)!;
        back.Devices.Count.ShouldBe(2);
        back.Devices[0].HostAddress.ShouldBe("ab://10.0.0.1/1,0");
        back.Devices[0].PlcFamily.ShouldBe(AbCipPlcFamily.ControlLogix);
        back.Devices[1].PlcFamily.ShouldBe(AbCipPlcFamily.CompactLogix);
    }

    // ---- Task 19: Transport (native AB transport switch) ----
    // These drive the form's OWN load/save path (TryDeserialize -> FromOptions -> ToOptions -> Serialize),
    // which uses the production JsonSerializerOptions, so a numeric enum or a dropped field shows up here.

    [Theory]
    [InlineData(AbCipTransport.Libplctag)]
    [InlineData(AbCipTransport.Native)]
    [InlineData(null)]
    public void Transport_survives_FromOptions_ToOptions(AbCipTransport? transport)
    {
        var original = new AbCipDriverOptions { Transport = transport };
        var back = AbCipDriverForm.FormModel.FromOptions(original).ToOptions([]);
        back.Transport.ShouldBe(transport);
    }

    [Fact]
    public void Native_transport_serializes_as_a_string()
    {
        var form = new AbCipDriverForm.FormModel { Transport = AbCipTransport.Native };
        var json = AbCipDriverForm.Serialize(form.ToOptions([]));
        json.ShouldContain("\"transport\":\"Native\"");
    }

    [Theory]
    [InlineData("Native", AbCipTransport.Native)]
    [InlineData("Libplctag", AbCipTransport.Libplctag)]
    public void Editing_an_unrelated_field_preserves_an_explicit_transport(string savedValue, AbCipTransport expected)
    {
        // The regression the review found: FromOptions/ToOptions dropped Transport, so an operator who set
        // a transport was silently reverted the next time they saved ANY other edit.
        var saved = $$"""{"transport":"{{savedValue}}","timeout":"00:00:02","devices":[]}""";
        var loaded = AbCipDriverForm.TryDeserialize(saved);
        loaded.ShouldNotBeNull();
        loaded.Transport.ShouldBe(expected);

        var form = AbCipDriverForm.FormModel.FromOptions(loaded);
        form.TimeoutSeconds = 7;
        var json = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices));

        json.ShouldContain($"\"transport\":\"{savedValue}\"");
        json.ShouldContain("\"timeoutMs\":7000");
    }

    [Fact]
    public void A_config_without_transport_loads_as_Default_and_an_unrelated_edit_keeps_the_key_absent()
    {
        // Task 22 reverses Task 19's "re-emit an explicit Libplctag": that would pin every edited driver to
        // a concrete transport and bypass the driver-side default (and AbLegacy's PLC-5 / LogixPccc
        // exclusion). Absent loads as Default (null) and a save that edits something else still omits it.
        var loaded = AbCipDriverForm.TryDeserialize("""{"probeTimeoutSeconds":5}""");
        loaded.ShouldNotBeNull();
        var form = AbCipDriverForm.FormModel.FromOptions(loaded);
        form.Transport.ShouldBeNull();

        form.TimeoutSeconds = 7;
        var json = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices));
        json.ShouldNotContain("transport", Case.Insensitive);
        json.ShouldContain("\"timeoutMs\":7000");
    }

    [Fact]
    public void Choosing_Default_over_an_explicit_transport_drops_the_key()
    {
        var loaded = AbCipDriverForm.TryDeserialize("""{"transport":"Libplctag"}""");
        loaded.ShouldNotBeNull();
        var form = AbCipDriverForm.FormModel.FromOptions(loaded);
        form.Transport.ShouldBe(AbCipTransport.Libplctag);

        form.Transport = null; // the "Default (...)" dropdown option
        AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices)).ShouldNotContain("transport", Case.Insensitive);
    }

    // ---- #576: preserve-unknown + MaxConcurrentReads ----

    private const string FullConfig = """
        {"transport":"Native","timeout":"00:00:05","maxConcurrentReads":3,"enableControllerBrowse":true,
         "enableDeclarationOnlyUdtGrouping":true,"enableAlarmProjection":true,"alarmPollInterval":"00:00:02",
         "probeTimeoutSeconds":12,
         "probe":{"enabled":true,"interval":"00:00:10","timeout":"00:00:03","probeTagPath":"Program:Main.Hb","futureProbeKnob":7},
         "devices":[{"hostAddress":"ab://10.0.0.1/1,0","plcFamily":"ControlLogix","deviceName":"PLC-1","futureDeviceKey":"keep"}],
         "rawTags":[{"rawPath":"a/b"}],
         "futureOption":{"nested":[1,2,3]},"anotherUnknown":"x"}
        """;

    [Fact]
    public void Editing_one_field_preserves_every_other_option_and_unknown_keys()
    {
        var loaded = AbCipDriverForm.TryDeserialize(FullConfig)!;
        var form = AbCipDriverForm.FormModel.FromOptions(loaded);
        form.TimeoutSeconds = 9; // the one edit

        var root = System.Text.Json.Nodes.JsonNode.Parse(
            AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), FullConfig))!.AsObject();

        root["timeoutMs"]!.GetValue<int>().ShouldBe(9000);
        root.ContainsKey("timeout").ShouldBeFalse();
        root["maxConcurrentReads"]!.GetValue<int>().ShouldBe(3); // was reset to 8 before #576
        root["transport"]!.GetValue<string>().ShouldBe("Native");
        root["enableControllerBrowse"]!.GetValue<bool>().ShouldBeTrue();
        root["enableDeclarationOnlyUdtGrouping"]!.GetValue<bool>().ShouldBeTrue();
        root["enableAlarmProjection"]!.GetValue<bool>().ShouldBeTrue();
        root["alarmPollIntervalMs"]!.GetValue<int>().ShouldBe(2000);
        root["probeTimeoutSeconds"]!.GetValue<int>().ShouldBe(12);
        root["probe"]!["enabled"]!.GetValue<bool>().ShouldBeTrue();
        root["probe"]!["intervalMs"]!.GetValue<int>().ShouldBe(10000);
        root["probe"]!["timeoutMs"]!.GetValue<int>().ShouldBe(3000);
        root["probe"]!["probeTagPath"]!.GetValue<string>().ShouldBe("Program:Main.Hb");
        // unknown keys at every level survive
        root["probe"]!["futureProbeKnob"]!.GetValue<int>().ShouldBe(7);
        root["devices"]![0]!["futureDeviceKey"]!.GetValue<string>().ShouldBe("keep");
        root["rawTags"]![0]!["rawPath"]!.GetValue<string>().ShouldBe("a/b");
        root["futureOption"]!["nested"]!.AsArray().Count.ShouldBe(3);
        root["anotherUnknown"]!.GetValue<string>().ShouldBe("x");
    }

    [Fact]
    public void Choosing_Default_transport_and_clearing_the_probe_path_removes_those_keys_from_the_overlay()
    {
        var loaded = AbCipDriverForm.TryDeserialize(FullConfig)!;
        var form = AbCipDriverForm.FormModel.FromOptions(loaded);
        form.Transport = null;
        form.ProbeTagPath = "";

        var root = System.Text.Json.Nodes.JsonNode.Parse(
            AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), FullConfig))!.AsObject();

        root.ContainsKey("transport").ShouldBeFalse();
        root["probe"]!.AsObject().ContainsKey("probeTagPath").ShouldBeFalse();
        root["futureOption"].ShouldNotBeNull();
    }

    [Fact]
    public void A_stored_PascalCase_key_is_replaced_not_duplicated()
    {
        var original = """{"Transport":"Native","TimeoutSeconds":1,"futureOption":true}""";
        var loaded = AbCipDriverForm.TryDeserialize(original)!;
        var form = AbCipDriverForm.FormModel.FromOptions(loaded);
        form.Transport = AbCipTransport.Libplctag;

        var json = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original);
        System.Text.RegularExpressions.Regex.Matches(json, "transport", System.Text.RegularExpressions.RegexOptions.IgnoreCase)
            .Count.ShouldBe(1);
        json.ShouldContain("\"transport\":\"Libplctag\"");
        json.ShouldContain("futureOption");
    }

    // ---- #576: the saved JSON must be what the driver FACTORY binds (integer-ms keys) ----

    [Fact]
    public void An_edited_timeout_reaches_the_factory_bound_options()
    {
        var original = """{"timeoutMs":5000,"alarmPollIntervalMs":500,"probe":{"enabled":true,"intervalMs":7000,"timeoutMs":1500,"probeTagPath":"Program:Main.Hb"},"devices":[{"hostAddress":"ab://10.0.0.1/1,0"}]}""";
        var loaded = AbCipDriverForm.TryDeserialize(original)!;
        var form = AbCipDriverForm.FormModel.FromJson(original, loaded);
        form.TimeoutSeconds.ShouldBe(5); // the form SEES the factory-keyed value
        form.TimeoutSeconds = 11;

        var saved = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original);
        var bound = ZB.MOM.WW.OtOpcUa.Driver.AbCip.AbCipDriverFactoryExtensions.ParseOptions("t", saved);

        bound.Timeout.ShouldBe(TimeSpan.FromSeconds(11));
        // untouched durations keep their exact stored value, including sub-second ones
        bound.AlarmPollInterval.ShouldBe(TimeSpan.FromMilliseconds(500));
        bound.Probe.Interval.ShouldBe(TimeSpan.FromSeconds(7));
        bound.Probe.Timeout.ShouldBe(TimeSpan.FromMilliseconds(1500));
        bound.Probe.ProbeTagPath.ShouldBe("Program:Main.Hb");
    }

    [Fact]
    public void A_legacy_TimeSpan_string_key_is_loaded_then_migrated_to_ms_and_removed()
    {
        var original = """{"timeout":"00:00:05","alarmPollInterval":"00:00:02","probe":{"interval":"00:00:10","timeout":"00:00:03"}}""";
        var loaded = AbCipDriverForm.TryDeserialize(original)!;
        var form = AbCipDriverForm.FormModel.FromJson(original, loaded);
        form.TimeoutSeconds.ShouldBe(5);
        form.TimeoutSeconds = 6;

        var saved = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original);
        var root = System.Text.Json.Nodes.JsonNode.Parse(saved)!.AsObject();
        root.ContainsKey("timeout").ShouldBeFalse();
        root.ContainsKey("alarmPollInterval").ShouldBeFalse();
        root["probe"]!.AsObject().ContainsKey("interval").ShouldBeFalse();
        root["probe"]!.AsObject().ContainsKey("timeout").ShouldBeFalse();

        var bound = ZB.MOM.WW.OtOpcUa.Driver.AbCip.AbCipDriverFactoryExtensions.ParseOptions("t", saved);
        bound.Timeout.ShouldBe(TimeSpan.FromSeconds(6));
        bound.AlarmPollInterval.ShouldBe(TimeSpan.FromSeconds(2));
        bound.Probe.Interval.ShouldBe(TimeSpan.FromSeconds(10));
        bound.Probe.Timeout.ShouldBe(TimeSpan.FromSeconds(3));
    }

    [Fact]
    public void A_form_saved_config_is_still_accepted_by_the_Test_Connect_probe_parse()
    {
        // The probe deserialises the typed options and skips unmapped keys, so the ms keys must not break it.
        var original = """{"timeoutMs":5000,"devices":[{"hostAddress":"ab://10.0.0.1/1,0"}]}""";
        var loaded = AbCipDriverForm.TryDeserialize(original)!;
        var form = AbCipDriverForm.FormModel.FromJson(original, loaded);
        form.TimeoutSeconds = 8;
        var saved = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original);

        var opts = System.Text.Json.JsonSerializer.Deserialize<AbCipDriverOptions>(saved, TestJsonOpts);
        opts.ShouldNotBeNull();
        opts.Devices[0].HostAddress.ShouldBe("ab://10.0.0.1/1,0");
    }

    // ---- #596: browsePageDelayMs is form-authorable, reaches the factory, and unknown keys survive ----

    [Fact]
    public void BrowsePageDelayMs_is_loaded_edited_and_bound_by_the_factory_without_dropping_unknown_keys()
    {
        var original = """{"browsePageDelayMs":40,"futureOption":"keep-me","devices":[{"hostAddress":"ab://10.0.0.1/1,0"}]}""";
        var loaded = AbCipDriverForm.TryDeserialize(original)!;
        var form = AbCipDriverForm.FormModel.FromJson(original, loaded);
        form.BrowsePageDelayMs.ShouldBe(40); // the form SEES the factory-keyed value

        var untouched = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original);
        ZB.MOM.WW.OtOpcUa.Driver.AbCip.AbCipDriverFactoryExtensions.ParseOptions("t", untouched)
            .BrowsePageDelay.ShouldBe(TimeSpan.FromMilliseconds(40));

        form.BrowsePageDelayMs = 125;
        var saved = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original);
        ZB.MOM.WW.OtOpcUa.Driver.AbCip.AbCipDriverFactoryExtensions.ParseOptions("t", saved)
            .BrowsePageDelay.ShouldBe(TimeSpan.FromMilliseconds(125));
        saved.ShouldContain("futureOption");
        System.Text.Json.Nodes.JsonNode.Parse(saved)!.AsObject().ContainsKey("browsePageDelay").ShouldBeFalse();
    }

    // ---- review R3-m4: the key is emitted only when loaded or changed from the default; negatives are flagged ----

    [Fact]
    public void BrowsePageDelayMs_is_omitted_when_never_set_and_left_at_the_default()
    {
        var original = """{"futureOption":"keep-me","devices":[{"hostAddress":"ab://10.0.0.1/1,0"}]}""";
        var loaded = AbCipDriverForm.TryDeserialize(original)!;
        var form = AbCipDriverForm.FormModel.FromJson(original, loaded);

        var saved = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original, form.EmitsBrowsePageDelay);
        System.Text.Json.Nodes.JsonNode.Parse(saved)!.AsObject().ContainsKey("browsePageDelayMs").ShouldBeFalse();
        saved.ShouldContain("futureOption");

        // Control: changing it away from the default DOES write it, and a loaded key is kept even at the default value.
        form.BrowsePageDelayMs = 125;
        var changed = AbCipDriverForm.Serialize(form.ToOptions(loaded.Devices), original, form.EmitsBrowsePageDelay);
        System.Text.Json.Nodes.JsonNode.Parse(changed)!["browsePageDelayMs"]!.GetValue<int>().ShouldBe(125);

        var withKey = """{"browsePageDelayMs":5,"devices":[{"hostAddress":"ab://10.0.0.1/1,0"}]}""";
        var f2 = AbCipDriverForm.FormModel.FromJson(withKey, AbCipDriverForm.TryDeserialize(withKey)!);
        f2.EmitsBrowsePageDelay.ShouldBeTrue();
    }

    [Fact]
    public void BrowsePageDelayMs_negative_is_a_validation_error_zero_is_valid()
    {
        var form = new AbCipDriverForm.FormModel { BrowsePageDelayMs = -1 };
        form.BrowsePageDelayError.ShouldNotBeNull();
        form.BrowsePageDelayMs = 0;
        form.BrowsePageDelayError.ShouldBeNull();
    }
}