// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the Apache 2.0 License.
// See the LICENSE file in the project root for more information. 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace System.Linq
{
    public static partial class AsyncEnumerable
    {
        public static Task<int> Sum(this IAsyncEnumerable<int> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate(0, (x, y) => x + y, cancellationToken);
        }

        public static Task<long> Sum(this IAsyncEnumerable<long> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate(0L, (x, y) => x + y, cancellationToken);
        }

        public static Task<double> Sum(this IAsyncEnumerable<double> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate(0.0, (x, y) => x + y, cancellationToken);
        }

        public static Task<float> Sum(this IAsyncEnumerable<float> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate(0f, (x, y) => x + y, cancellationToken);
        }

        public static Task<decimal> Sum(this IAsyncEnumerable<decimal> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate(0m, (x, y) => x + y, cancellationToken);
        }

        public static Task<int?> Sum(this IAsyncEnumerable<int?> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate((int?)0, (x, y) => x + y.GetValueOrDefault(), cancellationToken);
        }

        public static Task<long?> Sum(this IAsyncEnumerable<long?> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate((long?)0, (x, y) => x + y.GetValueOrDefault(), cancellationToken);
        }

        public static Task<double?> Sum(this IAsyncEnumerable<double?> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate((double?)0, (x, y) => x + y.GetValueOrDefault(), cancellationToken);
        }

        public static Task<float?> Sum(this IAsyncEnumerable<float?> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate((float?)0, (x, y) => x + y.GetValueOrDefault(), cancellationToken);
        }

        public static Task<decimal?> Sum(this IAsyncEnumerable<decimal?> source, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));

            return source.Aggregate((decimal?)0, (x, y) => x + y.GetValueOrDefault(), cancellationToken);
        }

        public static Task<int> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, int> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<long> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, long> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<double> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, double> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<float> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, float> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<decimal> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, decimal> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<int?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, int?> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<long?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, long?> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<double?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, double?> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }


        public static Task<int> Sum(this IAsyncEnumerable<int> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<long> Sum(this IAsyncEnumerable<long> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<double> Sum(this IAsyncEnumerable<double> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<float> Sum(this IAsyncEnumerable<float> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<decimal> Sum(this IAsyncEnumerable<decimal> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<int?> Sum(this IAsyncEnumerable<int?> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<long?> Sum(this IAsyncEnumerable<long?> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<double?> Sum(this IAsyncEnumerable<double?> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<float?> Sum(this IAsyncEnumerable<float?> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<decimal?> Sum(this IAsyncEnumerable<decimal?> source)
        {
            if (source == null)
                throw new ArgumentNullException("source");

            return Sum(source, CancellationToken.None);
        }

        public static Task<int> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, int> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<long> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, long> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<double> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, double> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<float> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, float> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<decimal> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, decimal> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<int?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, int?> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<long?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, long?> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<double?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, double?> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<float?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, float?> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }

        public static Task<decimal?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, decimal?> selector)
        {
            if (source == null)
                throw new ArgumentNullException("source");
            if (selector == null)
                throw new ArgumentNullException("selector");

            return Sum(source, selector, CancellationToken.None);
        }


        public static Task<float?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, float?> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }

        public static Task<decimal?> Sum<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, decimal?> selector, CancellationToken cancellationToken)
        {
            if (source == null)
                throw new ArgumentNullException(nameof(source));
            if (selector == null)
                throw new ArgumentNullException(nameof(selector));

            return source.Select(selector)
                         .Sum(cancellationToken);
        }
    }
}