using Microsoft.EntityFrameworkCore;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Admin.Services;
using ZB.MOM.WW.OtOpcUa.Configuration;
using ZB.MOM.WW.OtOpcUa.Configuration.Entities;
using ZB.MOM.WW.OtOpcUa.Configuration.Enums;

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

[Trait("Category", "Unit")]
public sealed class FocasDriverDetailServiceTests
{
    [Fact]
    public async Task GetAsync_returns_null_for_unknown_instance()
    {
        using var ctx = NewContext();
        var svc = new FocasDriverDetailService(ctx);
        (await svc.GetAsync("missing", CancellationToken.None)).ShouldBeNull();
    }

    [Fact]
    public async Task GetAsync_returns_null_for_non_focas_driver_type()
    {
        using var ctx = NewContext();
        ctx.DriverInstances.Add(NewInstance("drv-modbus", "ModbusTcp", "{}"));
        await ctx.SaveChangesAsync();

        var svc = new FocasDriverDetailService(ctx);
        (await svc.GetAsync("drv-modbus", CancellationToken.None)).ShouldBeNull();
    }

    [Fact]
    public async Task GetAsync_parses_devices_tags_and_alarm_projection()
    {
        using var ctx = NewContext();
        ctx.DriverInstances.Add(NewInstance("drv-focas", "Focas", """
        {
          "Devices": [
            { "HostAddress": "focas://10.20.30.40:8193", "Series": "ThirtyOne_i" }
          ],
          "Tags": [
            { "Name": "Mode", "DeviceHostAddress": "focas://10.20.30.40:8193",
              "Address": "PARAM:3402", "DataType": "Int32", "Writable": false }
          ],
          "AlarmProjection": { "Enabled": true, "PollInterval": "00:00:05" },
          "HandleRecycle":   { "Enabled": true, "Interval": "01:00:00" }
        }
        """));
        await ctx.SaveChangesAsync();

        var svc = new FocasDriverDetailService(ctx);
        var detail = await svc.GetAsync("drv-focas", CancellationToken.None);

        detail.ShouldNotBeNull();
        detail.ParseError.ShouldBeNull();
        detail.Config.ShouldNotBeNull();
        detail.Config.Devices!.Single().HostAddress.ShouldBe("focas://10.20.30.40:8193");
        detail.Config.Devices!.Single().Series.ShouldBe("ThirtyOne_i");
        detail.Config.Tags!.Single().Name.ShouldBe("Mode");
        detail.Config.AlarmProjection!.Enabled.ShouldBeTrue();
        detail.Config.HandleRecycle!.Enabled.ShouldBeTrue();
    }

    [Fact]
    public async Task GetAsync_surfaces_parse_error_for_malformed_json()
    {
        using var ctx = NewContext();
        ctx.DriverInstances.Add(NewInstance("drv-bad", "Focas", "{ not-valid-json"));
        await ctx.SaveChangesAsync();

        var svc = new FocasDriverDetailService(ctx);
        var detail = await svc.GetAsync("drv-bad", CancellationToken.None);

        detail.ShouldNotBeNull();
        detail.ParseError.ShouldNotBeNull();
        detail.Config.ShouldBeNull();
    }

    [Fact]
    public async Task GetAsync_joins_host_status_rows_for_the_instance()
    {
        using var ctx = NewContext();
        ctx.DriverInstances.Add(NewInstance("drv-focas", "Focas", "{}"));
        ctx.DriverHostStatuses.Add(new DriverHostStatus
        {
            NodeId = "node-A",
            DriverInstanceId = "drv-focas",
            HostName = "focas://10.0.0.1:8193",
            State = DriverHostState.Running,
            StateChangedUtc = DateTime.UtcNow.AddMinutes(-5),
            LastSeenUtc = DateTime.UtcNow.AddSeconds(-3),
        });
        await ctx.SaveChangesAsync();

        var svc = new FocasDriverDetailService(ctx);
        var detail = await svc.GetAsync("drv-focas", CancellationToken.None);

        detail.ShouldNotBeNull();
        detail.HostStatuses.Count.ShouldBe(1);
        detail.HostStatuses[0].HostName.ShouldBe("focas://10.0.0.1:8193");
        detail.HostStatuses[0].State.ShouldBe("Running");
    }

    [Fact]
    public async Task GetAsync_picks_latest_generation_when_multiple_rows_exist()
    {
        using var ctx = NewContext();
        ctx.DriverInstances.Add(NewInstance("drv-focas", "Focas", "{\"Tags\":[]}", generationId: 1));
        ctx.DriverInstances.Add(NewInstance("drv-focas", "Focas", """{"Tags":[{"Name":"later"}]}""", generationId: 2));
        await ctx.SaveChangesAsync();

        var svc = new FocasDriverDetailService(ctx);
        var detail = await svc.GetAsync("drv-focas", CancellationToken.None);

        detail.ShouldNotBeNull();
        detail.Config!.Tags!.Single().Name.ShouldBe("later");
    }

    private static DriverInstance NewInstance(
        string driverInstanceId, string driverType, string driverConfigJson, long generationId = 1) => new()
    {
        GenerationId = generationId,
        DriverInstanceId = driverInstanceId,
        ClusterId = "cluster-1",
        NamespaceId = "ns-1",
        Name = driverInstanceId,
        DriverType = driverType,
        DriverConfig = driverConfigJson,
    };

    private static OtOpcUaConfigDbContext NewContext()
    {
        var opts = new DbContextOptionsBuilder<OtOpcUaConfigDbContext>()
            .UseInMemoryDatabase(Guid.NewGuid().ToString())
            .Options;
        return new OtOpcUaConfigDbContext(opts);
    }
}