using ScadaLink.Commons.Types.DataConnections;
using ScadaLink.Commons.Types.Flattening;
using ScadaLink.Commons.Validators;

namespace ScadaLink.Commons.Tests.Validators;

public class OpcUaEndpointConfigValidatorTests
{
    private static OpcUaEndpointConfig Valid() => new()
    {
        EndpointUrl = "opc.tcp://plant-a:4840",
        // Defaults satisfy the spec: Lifetime(30) >= 3 * KeepAlive(10).
    };

    [Fact]
    public void Validate_DefaultsWithValidUrl_IsValid()
    {
        var result = OpcUaEndpointConfigValidator.Validate(Valid());
        Assert.True(result.IsValid);
        Assert.Empty(result.Errors);
    }

    [Fact]
    public void Validate_MissingEndpointUrl_Fails()
    {
        var c = Valid();
        c.EndpointUrl = "";
        var r = OpcUaEndpointConfigValidator.Validate(c);
        Assert.False(r.IsValid);
        Assert.Contains(r.Errors, e =>
            e.EntityName == "EndpointUrl"
            && e.Category == ValidationCategory.ConnectionConfig
            && e.Message.Contains("required", StringComparison.OrdinalIgnoreCase));
    }

    [Theory]
    [InlineData("http://x")]
    [InlineData("opc.tcp://")]
    [InlineData("not a url")]
    public void Validate_BadEndpointUrl_Fails(string url)
    {
        var c = Valid();
        c.EndpointUrl = url;
        var r = OpcUaEndpointConfigValidator.Validate(c);
        Assert.False(r.IsValid);
        Assert.Contains(r.Errors, e => e.EntityName == "EndpointUrl");
    }

    [Fact]
    public void Validate_LifetimeLessThanThreeTimesKeepAlive_Fails()
    {
        var c = Valid();
        c.KeepAliveCount = 10;
        c.LifetimeCount = 29; // 3*10 = 30; 29 < 30 → invalid
        var r = OpcUaEndpointConfigValidator.Validate(c);
        Assert.False(r.IsValid);
        Assert.Contains(r.Errors, e => e.EntityName == "LifetimeCount");
    }

    [Theory]
    [InlineData(nameof(OpcUaEndpointConfig.SessionTimeoutMs))]
    [InlineData(nameof(OpcUaEndpointConfig.OperationTimeoutMs))]
    [InlineData(nameof(OpcUaEndpointConfig.PublishingIntervalMs))]
    [InlineData(nameof(OpcUaEndpointConfig.SamplingIntervalMs))]
    public void Validate_NonPositiveTiming_Fails(string field)
    {
        var c = Valid();
        typeof(OpcUaEndpointConfig).GetProperty(field)!.SetValue(c, 0);
        var r = OpcUaEndpointConfigValidator.Validate(c);
        Assert.False(r.IsValid);
        Assert.Contains(r.Errors, e => e.EntityName == field);
    }

    [Fact]
    public void Validate_QueueSizeZero_Fails()
    {
        var c = Valid();
        c.QueueSize = 0;
        var r = OpcUaEndpointConfigValidator.Validate(c);
        Assert.Contains(r.Errors, e => e.EntityName == "QueueSize");
    }

    [Fact]
    public void Validate_HeartbeatEnabledNoTagPath_Fails()
    {
        var c = Valid();
        c.Heartbeat = new OpcUaHeartbeatConfig { TagPath = "", MaxSilenceSeconds = 30 };
        var r = OpcUaEndpointConfigValidator.Validate(c);
        Assert.Contains(r.Errors, e => e.EntityName == "Heartbeat.TagPath");
    }

    [Fact]
    public void Validate_HeartbeatNonPositiveSilence_Fails()
    {
        var c = Valid();
        c.Heartbeat = new OpcUaHeartbeatConfig { TagPath = "Hb", MaxSilenceSeconds = 0 };
        var r = OpcUaEndpointConfigValidator.Validate(c);
        Assert.Contains(r.Errors, e => e.EntityName == "Heartbeat.MaxSilenceSeconds");
    }

    [Fact]
    public void Validate_FieldPrefix_AppliedToEveryError()
    {
        var c = Valid();
        c.EndpointUrl = "";
        c.QueueSize = 0;
        var r = OpcUaEndpointConfigValidator.Validate(c, fieldPrefix: "Primary.");
        Assert.All(r.Errors, e => Assert.StartsWith("Primary.", e.EntityName!));
        Assert.Contains(r.Errors, e => e.EntityName == "Primary.EndpointUrl");
        Assert.Contains(r.Errors, e => e.EntityName == "Primary.QueueSize");
    }
}