using Microsoft.EntityFrameworkCore;
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.AdminUI.Tests.Uns;

/// <summary>
/// Shared in-memory fixture for <c>UnsTreeService</c> structural tests. Builds an
/// <see cref="OtOpcUaConfigDbContext"/> over a named InMemory database and seeds a small,
/// deterministic UNS hierarchy: enterprise "zb" across two clusters (MAIN populated,
/// SITE-A intentionally empty), plus tags and a virtual tag on one equipment node so
/// the per-equipment count joins can be exercised.
/// </summary>
internal static class UnsTreeTestDb
{
    /// <summary>The equipment that carries the seeded tags and virtual tag.</summary>
    public const string SeededEquipmentId = "EQ-000000000001";

    /// <summary>The cluster that has no areas, used to cover the empty-cluster case.</summary>
    public const string EmptyClusterId = "SITE-A";

    /// <summary>The populated cluster with the area→line→equipment path.</summary>
    public const string PopulatedClusterId = "MAIN";

    /// <summary>Creates a context over a fresh, uniquely-named InMemory database.</summary>
    public static OtOpcUaConfigDbContext Create() => CreateNamed($"uns-{Guid.NewGuid():N}");

    /// <summary>Creates a context bound to the supplied InMemory database name.</summary>
    public static OtOpcUaConfigDbContext CreateNamed(string name) =>
        new(new DbContextOptionsBuilder<OtOpcUaConfigDbContext>()
            .UseInMemoryDatabase(name)
            .Options);

    /// <summary>
    /// Returns an <see cref="IDbContextFactory{TContext}"/> whose contexts all share the
    /// supplied InMemory database name, so data seeded by <see cref="SeedNamed"/> is visible
    /// to the service under test.
    /// </summary>
    public static IDbContextFactory<OtOpcUaConfigDbContext> Factory(string name) => new NamedFactory(name);

    /// <summary>Seeds the fixture into the supplied (already-bound) context and saves.</summary>
    public static void Seed(OtOpcUaConfigDbContext db)
    {
        // Two clusters under the same enterprise; only MAIN gets a hierarchy.
        db.ServerClusters.Add(new ServerCluster
        {
            ClusterId = PopulatedClusterId,
            Name = "Main",
            Enterprise = "zb",
            Site = "warsaw-west",
            RedundancyMode = RedundancyMode.None,
            CreatedBy = "test",
        });
        db.ServerClusters.Add(new ServerCluster
        {
            ClusterId = EmptyClusterId,
            Name = "Site A",
            Enterprise = "zb",
            Site = "site-a",
            RedundancyMode = RedundancyMode.None,
            CreatedBy = "test",
        });

        // MAIN: one area → one line → one equipment.
        db.UnsAreas.Add(new UnsArea
        {
            UnsAreaId = "AREA-1",
            ClusterId = PopulatedClusterId,
            Name = "assembly",
        });
        db.UnsLines.Add(new UnsLine
        {
            UnsLineId = "LINE-1",
            UnsAreaId = "AREA-1",
            Name = "line-a",
        });
        db.Equipment.Add(new Equipment
        {
            EquipmentId = SeededEquipmentId,
            EquipmentUuid = Guid.NewGuid(),
            UnsLineId = "LINE-1",
            Name = "machine-1",
            MachineCode = "machine_001",
        });

        // Two driver tags + one virtual tag on the seeded equipment → ChildCount 3.
        db.Tags.Add(new Tag
        {
            TagId = "TAG-1",
            DriverInstanceId = "DRV-1",
            EquipmentId = SeededEquipmentId,
            Name = "speed",
            DataType = "Float",
            AccessLevel = TagAccessLevel.Read,
            TagConfig = "{}",
        });
        db.Tags.Add(new Tag
        {
            TagId = "TAG-2",
            DriverInstanceId = "DRV-1",
            EquipmentId = SeededEquipmentId,
            Name = "running",
            DataType = "Boolean",
            AccessLevel = TagAccessLevel.Read,
            TagConfig = "{}",
        });
        // A tag with no equipment must be ignored by the count query.
        db.Tags.Add(new Tag
        {
            TagId = "TAG-ORPHAN",
            DriverInstanceId = "DRV-1",
            EquipmentId = null,
            Name = "orphan",
            DataType = "Int32",
            AccessLevel = TagAccessLevel.Read,
            TagConfig = "{}",
        });
        db.VirtualTags.Add(new VirtualTag
        {
            VirtualTagId = "VTAG-1",
            EquipmentId = SeededEquipmentId,
            Name = "computed",
            DataType = "Double",
            ScriptId = "SCRIPT-1",
        });

        db.SaveChanges();
    }

    /// <summary>Seeds the fixture into a context bound to the supplied InMemory database name.</summary>
    public static void SeedNamed(string name)
    {
        using var db = CreateNamed(name);
        Seed(db);
    }

    /// <summary>
    /// Minimal <see cref="IDbContextFactory{TContext}"/> that hands back contexts sharing a
    /// single InMemory database name — the test-side stand-in for the runtime pooled factory.
    /// </summary>
    private sealed class NamedFactory(string name) : IDbContextFactory<OtOpcUaConfigDbContext>
    {
        public OtOpcUaConfigDbContext CreateDbContext() => CreateNamed(name);

        public Task<OtOpcUaConfigDbContext> CreateDbContextAsync(CancellationToken cancellationToken = default) =>
            Task.FromResult(CreateNamed(name));
    }
}