NejCommon.NET/Utils/Extensions.cs

using System.Globalization;
using System.Linq.Expressions;
using AutoMapPropertyHelper;
using EntityFrameworkCore.Projectables;
using EntityFrameworkCore.Projectables.Extensions;
using Microsoft.EntityFrameworkCore;
using NejCommon.Controllers;
using NejCommon.Models;

namespace NejCommon.Utils;

public static class Extensions
{
    public static IQueryable<TType> ApplyPagination<TType>(this IQueryable<TType> query, Pagination pag)
    {
        query = query.Skip(pag.Offset);
        query = query.Take(pag.Count);
        return query;
    }

    public static async Task<PaginationResponse<TResponseType>> ApplyPaginationRes<TType, TResponseType>(this IQueryable<TType> query, IServiceProvider providers, Pagination pag) where TResponseType : IAutomappedAttribute<TType, TResponseType>, new()
    {
        var totalCount = await query.CountAsync();
        query = query.Skip(pag.Offset);
        query = query.Take(pag.Count);
        var projector = new TResponseType().GetProjectorFrom(providers);

        return new PaginationResponse<TResponseType>
        {
            TotalCount = totalCount,
            Offset = pag.Offset,
            Count = pag.Count,
            Data = query.Select(projector).AsAsyncEnumerable()
        };
    }

    public static async Task<PaginationResponse<TResponseType>> ApplySearchPaginationRes<TType, TResponseType, TEntityBinder>(this IQueryable<TType> query, string? search, IServiceProvider providers, Pagination pag, List<Expression<Func<TType, string, bool>>> matchers)
        where TType : class
        where TResponseType : IAutomappedAttribute<TType, TResponseType>, new()
        where TEntityBinder : EntityBinder<TType>
    {
        if (search != null)
        {
            var searchers = new List<Expression<Func<TType, bool>>>();
            foreach (var matcher in matchers)
            {
                //reduce expression from TType, string, bool to TType, bool by passing the search string

                var par = Expression.Parameter(typeof(TType));
                var exp = Expression.Invoke(matcher, par, Expression.Constant(search));
                var redExp = exp.Reduce();
                var reducedMatcher = Expression.Lambda<Func<TType, bool>>(redExp, par);

                searchers.Add(reducedMatcher);
            }

            var extPar = Expression.Parameter(typeof(TType));

            using (var scope = providers.CreateScope())
            {
                var binder = scope.ServiceProvider.GetRequiredService<TEntityBinder>();
                var idMatcher = binder.RouteValues.First(x => x.Primary).Expression;
                var reducedIdMatcher = Expression.Lambda<Func<TType, bool>>(Expression.Invoke(idMatcher, extPar, Expression.Constant(search)).Reduce(), extPar);
                //Console.Writeline(reducedIdMatcher);
                searchers.Add(reducedIdMatcher);

                // Create an expression that ORs all the searchers
                var agrPar = Expression.Parameter(typeof(TType));

                var orExp = searchers.Aggregate((Expression)null, (current, searcher) =>
                {
                    var body = Expression.Invoke(searcher, agrPar);
                    if (current == null)
                    {
                        return body;
                    }
                    return Expression.OrElse(current, body);
                });

                //reduce the epxression as much as possible
                while (orExp.CanReduce)
                {
                    orExp = orExp.Reduce();
                }

                var orLambda = Expression.Lambda<Func<TType, bool>>(orExp, agrPar);
                //Console.Writeline(orLambda);
                query = query.Where(orLambda);
            }
        }

        return await query.ApplyPaginationRes<TType, TResponseType>(providers, pag);
    }

    [Projectable]
    public static IQueryable<TType> ApplyDateOnlyFrameQ<TType>(this IQueryable<TType> query, Func<TType, DateOnly> dateAcessor, DateOnlyFrame frame) => query.Where(e => dateAcessor(e) >= frame.fromDate && dateAcessor(e) <= frame.toDate);
    [Projectable]
    public static IEnumerable<TType> ApplyDateOnlyFrameE<TType>(this ICollection<TType> query, Func<TType, DateOnly> dateAcessor, DateOnlyFrame frame) => query.Where(e => dateAcessor(e) >= frame.fromDate && dateAcessor(e) <= frame.toDate);

    [Projectable]
    public static IQueryable<TType> ApplyDateTimeFrameQ<TType>(this IQueryable<TType> query, string datePropery, DateTimeFrame frame) => query.Where(e => EF.Property<DateTime>(e, datePropery) >= frame.FromDate && EF.Property<DateTime>(e, datePropery) <= frame.ToDate);
    [Projectable]
    public static IEnumerable<TType> ApplyDateTimeFrameE<TType>(this ICollection<TType> query, Func<TType, DateTime> dateAcessor, DateTimeFrame frame) => query.Where(e => dateAcessor(e) >= frame.FromDate && dateAcessor(e) <= frame.ToDate);

    [Projectable]
    public static DateOnly ToDateOnly(this DateTime date) => new DateOnly(date.Year, date.Month, date.Day);
    [Projectable]
    public static DateTime ToDateTime(this DateOnly date) => new DateTime(date.Year, date.Month, date.Day);
    [Projectable]
    public static decimal Round(this decimal value, int decimals = 2) => Math.Round(value, decimals);
    [Projectable]
    public static decimal Floor(this decimal value, int decimals = 2) => Math.Floor(value * (decimal)Math.Pow(10, decimals)) / (decimal)Math.Pow(10, decimals);
    [Projectable]
    public static int RountToInt(this decimal value) => (int)Math.Round(value);

    [Projectable]
    public static int GetInt(this string value, NumberStyles? style = null, CultureInfo? culture = null) => int.Parse(value, style ?? NumberStyles.Number, culture ?? CultureInfo.InvariantCulture);
    [Projectable]
    public static decimal GetDecimal(this string value, NumberStyles? style = null, CultureInfo? culture = null) => decimal.Parse(value, style ?? NumberStyles.Number, culture ?? CultureInfo.InvariantCulture);
    [Projectable]
    public static float GetFloat(this string value, NumberStyles? style = null, CultureInfo? culture = null) => float.Parse(value, style ?? NumberStyles.Number, culture ?? CultureInfo.InvariantCulture);
}