using System.Net;
using Lagrange.Core;
using Lagrange.Core.Common.Interface.Api;

namespace Lagrange.OneBot.Core.Notify;

public class TicketService
{
    private readonly BotContext _context;

    private readonly HttpClient _client;

    private readonly CookieContainer _container;

    private readonly Dictionary<string, (string PsSey, DateTime ExpireTime)> _psKeys;

    private (string SKey, DateTime ExpireTime) _sKey;

    public TicketService(BotContext context)
    {
        _container = new CookieContainer();
        _context = context;

        var handler = new HttpClientHandler
        {
            CookieContainer = _container
        };
        _client = new HttpClient(handler);
        _psKeys = new Dictionary<string, (string, DateTime)>();
    }

    public async Task<HttpResponseMessage> SendAsync(HttpRequestMessage message, string? domain = null)
    {
        if (!message.Headers.Contains("Cookie")) message.Headers.Add("Cookie", await GetCookies(domain ?? message.RequestUri?.Host ?? ""));
        return await _client.SendAsync(message);
    }

    public async Task<int> GetCsrfToken()
    {
        string? sKey = await GetSKey();
        if (sKey == null) throw new InvalidDataException();

        int hash = 5381;
        for (int i = 0, len = sKey.Length; i < len; ++i)
        {
            hash += (hash << 5) + sKey[i];
        }
        return hash & 2147483647;
    }

    private async Task<string?> GetSKey()
    {
        if (DateTime.Now < _sKey.ExpireTime) return _sKey.SKey;

        const string jump = "https%3A%2F%2Fh5.qzone.qq.com%2Fqqnt%2Fqzoneinpcqq%2Ffriend%3Frefresh%3D0%26clientuin%3D0%26darkMode%3D0&keyindex=19&random=2599";
        string url = $"https://ssl.ptlogin2.qq.com/jump?ptlang=1033&clientuin={_context.BotUin}&clientkey={await _context.GetClientKey()}&u1={jump}";
        await _client.GetAsync(url);

        var cookies = _container.GetAllCookies();
        string sKey = cookies["skey"]?.Value ?? "";
        _sKey = (sKey, DateTime.Now.AddDays(1));

        return sKey;
    }

    public async Task<string> GetCookies(string domain)
    {
        string? skey = await GetSKey();
        string token;
        if (_psKeys.TryGetValue(domain, out var tokenTime))
        {
            if (DateTime.Now > tokenTime.ExpireTime)
            {
                token = (await _context.FetchCookies([domain]))[0];
                _psKeys[domain] = (token, DateTime.Now.AddDays(1)); // update pskey
            }
            else
            {
                token = tokenTime.PsSey;
            }
        }
        else
        {
            token = (await _context.FetchCookies([domain]))[0];
            _psKeys[domain] = (token, DateTime.Now.AddDays(1)); // get pskey
        }

        return $"p_uin=o{_context.BotUin}; p_skey={token}; skey={skey}; uin=o{_context.BotUin}";
    }
}