using System;
using System.IO;
using System.Net;
using System.Text;
using ln.http.content;

namespace ln.http;

public class Http1XConnection : HttpConnection
{
    bool _keepAlive;
    
    public Http1XConnection(Listener listener, IPEndPoint remoteEndpoint, Stream connectionStream, string method, string requestUriLine, HttpVersion httpVersion) 
        : base(listener, remoteEndpoint, connectionStream, method, requestUriLine, httpVersion)
    {
        if (httpVersion == HttpVersion.HTTP11)
            _keepAlive = true;
    }

    public override void Run()
    {
        string _method = Method;
        HttpVersion _httpVersion = HttpVersion;
        HeaderContainer headerContainer = new HeaderContainer();
        string _requestUriLine = RequestUriLine;

        while (ConnectionStream.CanRead && ConnectionStream.CanWrite)
        {
            headerContainer.Clear();
            headerContainer.Read(ConnectionStream);
            
            Uri BaseURI = new Uri($"{(Listener is TlsListener ? "https" : "http")}://{headerContainer.Get("host")}");
            Uri RequestUri = new Uri(BaseURI, _requestUriLine);
            
            if (
                headerContainer.TryGetHeader("connection", out Header connectionHeader)
            )
            {
                switch (connectionHeader.Value)
                {
                    case "close":
                        _keepAlive = false;
                        break;
                    case "keep-alive":
                        _keepAlive = true;
                        break;
                }
            }

            HttpContentStream contentStream = null;
            if (headerContainer.TryGetInteger("content-length", out int contentLength))
            {
                if (headerContainer.TryGetValue("Expect", out string expectValue) && expectValue.Equals("100-continue"))
                {
                    string statusLine = $"{HttpVersionSupport.ToString(_httpVersion)} 417 expectation failed\r\n";
                    byte[] statusLineBytes = Encoding.ASCII.GetBytes(statusLine);
                    ConnectionStream.Write(statusLineBytes);
                    break;
                }
                contentStream = new HttpContentStream(ConnectionStream, contentLength);
            }

            HttpRequestContext requestContext = new HttpRequestContext(Listener, this, ConnectionStream, new HttpRequest(_method, RequestUri, _httpVersion, false, headerContainer, contentStream));
            Listener.Dispatch(requestContext);

            if (!ConnectionStream.CanWrite && !ConnectionStream.CanRead)
                break;

            SendResponse(requestContext);
            ConnectionStream.Flush();
            
            string responseConnectionHeader = requestContext.Response.GetHeader("connection");
            _keepAlive = responseConnectionHeader switch
            {
                "close" => false,
                "keep-alive" => true,
                _ => _keepAlive
            };

            requestContext.Dispose();

            if (!_keepAlive)
                break;

            if (!HttpConnection.ReadRequestLine(ConnectionStream, out _method, out _requestUriLine, out _httpVersion))
                break;
        }
    }
    
    public override void SendResponse(HttpRequestContext requestContext)
    {
        foreach (var httpCookie in requestContext.Response.Cookies)
            requestContext.Response.Headers.Add("Set-Cookie", httpCookie.ToString());

        string statusLine = $"{HttpVersionSupport.ToString(requestContext.Request.HttpVersion)} {(int)requestContext.Response.HttpStatusCode} {requestContext.Response.HttpStatusCode.ToString()}\r\n";
        byte[] statusLineBytes = Encoding.ASCII.GetBytes(statusLine);
        requestContext.ConnectionStream.Write(statusLineBytes, 0, statusLineBytes.Length);
        if (!requestContext.Response.Headers.Contains("content-type"))
            requestContext.Response.Headers.Set("content-type", requestContext.Response.HttpContent?.ContentType);
        requestContext.Response.Headers.Set("content-length", requestContext.Response.HttpContent?.Length.ToString() ?? "0");
        requestContext.Response.Headers.CopyTo(requestContext.ConnectionStream);
        requestContext.Response.HttpContent?.CopyTo(requestContext.ConnectionStream);
    }

}