using Microsoft.Extensions.Configuration;
using ZB.MOM.WW.ScadaBridge.Host;
using ZB.MOM.WW.Telemetry;

namespace ZB.MOM.WW.ScadaBridge.Host.Tests;

/// <summary>
/// scadaproj#55: the logger and the AddZbTelemetry registration fill their options from one place,
/// so <c>ScadaBridge:Telemetry:Exporter=Otlp</c> reaches the pre-host logger (OTLP log sink) as well as
/// metrics and traces, and the node identity is unchanged.
/// </summary>
public class ScadaBridgeTelemetryConfigTests
{
    private static IConfiguration Config(Dictionary<string, string?> values) =>
        new ConfigurationBuilder().AddInMemoryCollection(values).Build();

    /// <summary>Exporter and endpoint come from ScadaBridge:Telemetry; identity from the arguments.</summary>
    [Fact]
    public void Apply_CarriesExporterAndIdentity()
    {
        var options = new ZbTelemetryOptions();

        ScadaBridgeTelemetryConfig.Apply(options, Config(new()
        {
            ["ScadaBridge:Telemetry:Exporter"] = "Otlp",
            ["ScadaBridge:Telemetry:OtlpEndpoint"] = "http://collector:4317",
        }), siteId: "site-a", nodeRole: "Site");

        Assert.Equal("scadabridge", options.ServiceName);
        Assert.Equal(ZbExporter.Otlp, options.Exporter);
        Assert.Equal("http://collector:4317", options.OtlpEndpoint);
        Assert.Equal("site-a", options.SiteId);
        Assert.Equal("Site", options.NodeRole);
        Assert.Null(options.ServiceVersion); // library default: entry-assembly informational version
    }

    /// <summary>A Telemetry-section SiteId/NodeRole cannot make the Resource diverge from the log enrichers.</summary>
    [Fact]
    public void Apply_NodeIdentityWinsOverTelemetrySection()
    {
        var options = new ZbTelemetryOptions();

        ScadaBridgeTelemetryConfig.Apply(options, Config(new()
        {
            ["ScadaBridge:Telemetry:SiteId"] = "other",
            ["ScadaBridge:Telemetry:NodeRole"] = "other",
        }), siteId: "central", nodeRole: "Central");

        Assert.Equal("central", options.SiteId);
        Assert.Equal("Central", options.NodeRole);
        Assert.Equal(ZbExporter.Prometheus, options.Exporter);
    }

    /// <summary>The OTLP logger path builds (validation passes) and still logs to the configured sinks.</summary>
    [Fact]
    public void CreateLogger_WithOtlpExporter_Builds()
    {
        var config = Config(new()
        {
            ["ScadaBridge:Telemetry:Exporter"] = "Otlp",
            ["ScadaBridge:Telemetry:OtlpEndpoint"] = "http://127.0.0.1:1",
        });

        using var logger = ScadaBridgeLogging.CreateLogger(config, "Site", "site-a", "node-a", TextWriter.Null, additionalConfiguration: null);
        logger.Information("otlp wiring smoke test");
    }

    /// <summary>A scheme-less endpoint now fails the logger at startup (Telemetry 0.3.0 validation).</summary>
    [Fact]
    public void CreateLogger_WithSchemelessEndpoint_Throws()
    {
        var config = Config(new()
        {
            ["ScadaBridge:Telemetry:Exporter"] = "Otlp",
            ["ScadaBridge:Telemetry:OtlpEndpoint"] = "collector:4317",
        });

        Assert.Throws<ArgumentException>(() =>
            ScadaBridgeLogging.CreateLogger(config, "Site", "site-a", "node-a", TextWriter.Null, additionalConfiguration: null));
    }
}