using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Infrastructure;
using Microsoft.EntityFrameworkCore.Metadata;
using Microsoft.Extensions.DependencyInjection;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.Configuration.Entities;

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

/// <summary>
///     Verifies the Phase 7 Stream E entities (<see cref="Script"/>, <see cref="VirtualTag"/>,
///     <see cref="ScriptedAlarm"/>) register correctly in the EF model, map to the expected
///     tables/columns/indexes, and carry the check constraints the plan decisions call for.
///     Introspection only — no SQL Server required.
/// </summary>
[Trait("Category", "Unit")]
public sealed class ScriptingEntitiesTests
{
    private static OtOpcUaConfigDbContext BuildCtx()
    {
        var options = new DbContextOptionsBuilder<OtOpcUaConfigDbContext>()
            .UseSqlServer("Server=(local);Database=dummy;Integrated Security=true") // not connected
            .Options;
        return new OtOpcUaConfigDbContext(options);
    }

    private static Microsoft.EntityFrameworkCore.Metadata.IModel DesignModel(OtOpcUaConfigDbContext ctx)
        => ctx.GetService<IDesignTimeModel>().Model;

    /// <summary>Verifies that the Script entity is registered with the expected table name and columns.</summary>
    [Fact]
    public void Script_entity_registered_with_expected_table_and_columns()
    {
        using var ctx = BuildCtx();
        var entity = ctx.Model.FindEntityType(typeof(Script)).ShouldNotBeNull();

        entity.GetTableName().ShouldBe("Script");
        entity.FindProperty(nameof(Script.ScriptRowId)).ShouldNotBeNull();
        entity.FindProperty(nameof(Script.ScriptId)).ShouldNotBeNull()
            .GetMaxLength().ShouldBe(64);
        entity.FindProperty(nameof(Script.SourceCode)).ShouldNotBeNull()
            .GetColumnType().ShouldBe("nvarchar(max)");
        entity.FindProperty(nameof(Script.SourceHash)).ShouldNotBeNull()
            .GetMaxLength().ShouldBe(64);
        entity.FindProperty(nameof(Script.Language)).ShouldNotBeNull()
            .GetMaxLength().ShouldBe(16);
    }

    /// <summary>Verifies that the Script entity has a unique logical ID constraint.</summary>
    [Fact]
    public void Script_has_unique_logical_id()
    {
        // v2 live-edit dropped the per-generation qualifier; Script.ScriptId is globally unique.
        using var ctx = BuildCtx();
        var entity = ctx.Model.FindEntityType(typeof(Script)).ShouldNotBeNull();
        entity.GetIndexes().Any(i => i.IsUnique).ShouldBeTrue("Script needs at least one unique index");
    }

    /// <summary>Verifies that the VirtualTag entity is registered with the expected trigger check constraint.</summary>
    [Fact]
    public void VirtualTag_entity_registered_with_trigger_check_constraint()
    {
        using var ctx = BuildCtx();
        var entity = DesignModel(ctx).FindEntityType(typeof(VirtualTag)).ShouldNotBeNull();
        entity.GetTableName().ShouldBe("VirtualTag");

        var checks = entity.GetCheckConstraints().Select(c => c.Name).ToArray();
        checks.ShouldContain("CK_VirtualTag_Trigger_AtLeastOne");
        checks.ShouldContain("CK_VirtualTag_TimerInterval_Min");
    }

    /// <summary>Verifies that the VirtualTag entity has a unique index on its logical key.</summary>
    [Fact]
    public void VirtualTag_has_unique_index_on_logical_key()
    {
        // v2 live-edit dropped the per-generation qualifier on VirtualTag's uniqueness.
        using var ctx = BuildCtx();
        var entity = ctx.Model.FindEntityType(typeof(VirtualTag)).ShouldNotBeNull();
        entity.GetIndexes().Any(i => i.IsUnique).ShouldBeTrue("VirtualTag needs at least one unique index");
    }

    /// <summary>Verifies that the VirtualTag entity has ChangeTriggered, Historize, and TimerIntervalMs properties.</summary>
    [Fact]
    public void VirtualTag_has_ChangeTriggered_and_Historize_flags()
    {
        using var ctx = BuildCtx();
        var entity = ctx.Model.FindEntityType(typeof(VirtualTag)).ShouldNotBeNull();
        entity.FindProperty(nameof(VirtualTag.ChangeTriggered)).ShouldNotBeNull()
            .ClrType.ShouldBe(typeof(bool));
        entity.FindProperty(nameof(VirtualTag.Historize)).ShouldNotBeNull()
            .ClrType.ShouldBe(typeof(bool));
        entity.FindProperty(nameof(VirtualTag.TimerIntervalMs)).ShouldNotBeNull()
            .ClrType.ShouldBe(typeof(int?));
    }

    /// <summary>Verifies that the ScriptedAlarm entity is registered with severity and type check constraints.</summary>
    [Fact]
    public void ScriptedAlarm_entity_registered_with_severity_and_type_checks()
    {
        using var ctx = BuildCtx();
        var entity = DesignModel(ctx).FindEntityType(typeof(ScriptedAlarm)).ShouldNotBeNull();
        entity.GetTableName().ShouldBe("ScriptedAlarm");

        var checks = entity.GetCheckConstraints().Select(c => c.Name).ToArray();
        checks.ShouldContain("CK_ScriptedAlarm_Severity_Range");
        checks.ShouldContain("CK_ScriptedAlarm_AlarmType");
    }

    /// <summary>Verifies that ScriptedAlarm has HistorizeToAveva defaulted to true per plan decision 15.</summary>
    [Fact]
    public void ScriptedAlarm_has_HistorizeToAveva_default_true_per_plan_decision_15()
    {
        // Defaults live on the CLR default assignment — verify the initializer.
        var alarm = new ScriptedAlarm
        {
            ScriptedAlarmId = "a1",
            EquipmentId = "eq1",
            Name = "n",
            AlarmType = "LimitAlarm",
            MessageTemplate = "m",
            PredicateScriptId = "s1",
        };
        alarm.HistorizeToAveva.ShouldBeTrue();
        alarm.Retain.ShouldBeTrue();
        alarm.Severity.ShouldBe(500);
        alarm.Enabled.ShouldBeTrue();
    }

    // The ConfigDb-backed ScriptedAlarmState entity + table were retired in per-cluster mesh Phase 4
    // (Task 9): scripted-alarm condition state lives in the replicated LocalDb store. The entity-model
    // tests that covered it are gone with it.

    /// <summary>Verifies that all new Phase 7 entities are exposed via DbSet properties.</summary>
    [Fact]
    public void All_new_entities_exposed_via_DbSet()
    {
        using var ctx = BuildCtx();
        ctx.Scripts.ShouldNotBeNull();
        ctx.VirtualTags.ShouldNotBeNull();
        ctx.ScriptedAlarms.ShouldNotBeNull();
    }

    /// <summary>Verifies that the squashed V3Initial migration exists in the assembly.</summary>
    [Fact]
    public void V3Initial_migration_exists_in_assembly()
    {
        // v3 WP1 squashed every prior migration into V3Initial. The migration type carries the
        // design-time snapshot + Up/Down (incl. the scripting tables) EF uses to apply the schema.
        var t = typeof(Migrations.V3Initial);
        t.ShouldNotBeNull();
    }
}