using System;
using System.Collections.Generic;
using System.Linq.Expressions;

using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Query.SqlExpressions;

namespace ASC.Core.Common.EF.Model
{
    public class ModelBuilderWrapper
    {
        private ModelBuilder ModelBuilder { get; set; }
        private Provider Provider { get; set; }

        private ModelBuilderWrapper(ModelBuilder modelBuilder, Provider provider)
        {
            ModelBuilder = modelBuilder;
            Provider = provider;
        }

        public static ModelBuilderWrapper From(ModelBuilder modelBuilder, Provider provider)
        {
            return new ModelBuilderWrapper(modelBuilder, provider);
        }

        public ModelBuilderWrapper Add(Action<ModelBuilder> action, Provider provider)
        {
            if (provider == Provider)
            {
                action(ModelBuilder);
            }

            return this;
        }

        public ModelBuilderWrapper HasData<T>(params T[] data) where T : class
        {
            ModelBuilder.Entity<T>().HasData(data);

            return this;
        }

        public void AddDbFunction()
        {
            ModelBuilder
                .HasDbFunction(typeof(JsonExtensions).GetMethod(nameof(JsonExtensions.JsonValue)))
                .HasTranslation(e =>
                {
                    var res = new List<SqlExpression>();
                    if (e is List<SqlExpression> list)
                    {
                        if (list[0] is SqlConstantExpression key)
                        {
                            res.Add(new SqlFragmentExpression($"`{key.Value}`"));
                        }

                        if (list[1] is SqlConstantExpression val)
                        {
                            res.Add(new SqlConstantExpression(Expression.Constant($"$.{val.Value}"), val.TypeMapping));
                        }
                    }

                    return SqlFunctionExpression.Create("JSON_EXTRACT", res, typeof(string), null);
                });
        }
    }
}