using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Diagnostics;
using Microsoft.EntityFrameworkCore.Infrastructure;
using Microsoft.EntityFrameworkCore.Migrations.Internal;
using Microsoft.EntityFrameworkCore.Migrations;
using System.Reflection;
using Elsa.EntityFrameworkCore.Common.Contracts;

namespace Elsa.EntityFrameworkCore.Common;

/// <summary>
/// Class That enable Schema change for Migration
/// </summary>
public class DbSchemaAwareMigrationAssembly : MigrationsAssembly
{
    private readonly DbContext _context;

    public DbSchemaAwareMigrationAssembly(ICurrentDbContext currentContext,
          IDbContextOptions options, IMigrationsIdGenerator idGenerator,
          IDiagnosticsLogger<DbLoggerCategory.Migrations> logger)
      : base(currentContext, options, idGenerator, logger)
    {
        _context = currentContext.Context;
    }

    public override Migration CreateMigration(TypeInfo migrationClass,
          string activeProvider)
    {
        if (activeProvider == null)
            throw new ArgumentNullException(nameof(activeProvider));

        var hasCtorWithSchema = migrationClass
                .GetConstructor(new[] { typeof(IElsaDbContextSchema) }) != null;

        if (hasCtorWithSchema && _context is IElsaDbContextSchema schema)
        {
            var instance = (Migration)Activator.CreateInstance(migrationClass.AsType(), schema);
            instance.ActiveProvider = activeProvider;
            return instance;
        }

        return base.CreateMigration(migrationClass, activeProvider);
    }
}