using System;
using System.Buffers;
using System.Collections.Generic;
using System.Linq;
using System.Net.Http;
using System.Threading;
using System.Threading.Tasks;
using Wabbajack.RateLimiter;

namespace Wabbajack.Networking.Http
{
    public static class HttpClientExtensions
    {
        public static IEnumerable<(string Key, string Value)> GetSetCookies(this HttpResponseMessage response)
        {
            if (!response.Headers.TryGetValues("set-cookie", out var values))
                return Array.Empty<(string, string)>();

            return values
                .SelectMany(h => h.Split(";"))
                .Select(h => h.Split("="))
                .Where(h => h.Length == 2)
                .Select(h => (h[0], h[1]));
        }

        public static async Task<IMemoryOwner<byte>> ReadAsByteArrayAsync(this HttpContent content, IJob job, CancellationToken token)
        {
            await using var stream = await content.ReadAsStreamAsync(token);
            var memory = MemoryPool<byte>.Shared.Rent((int)(job.Size));

            while (job.Current < job.Size)
            {
                var read = await stream.ReadAsync(memory.Memory[(int)job.Current..(int)job.Size], token);
                await job.Report(read, token);
            }

            if (job.Current != job.Size)
                throw new Exception("Overread error");

            return memory;
        }
    }
}