using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using ln.http.content;
using ln.json;
using ln.type;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace ln.http
{
    public class HttpRequest : IDisposable
    {
        public string RequestMethodName { get; }
        public Uri RequestUri { get; private set; }
        public HttpVersion HttpVersion { get; }
        public HeaderContainer Headers { get; }
        
        public HttpMethod Method { get; private set; }
        public String Host { get; private set; }
        public int Port { get; private set; }
        public bool ViaTLS { get; private set; }
        
        public QueryStringParameters Query { get; private set; }
        public Uri BaseUri { get; private set; }
        
        
        Dictionary<String, String> requestCookies;
        public HttpContentStream ContentStream { get; }
        
        public HttpRequest(string requestMethodName, Uri requestUri, HttpVersion httpVersion, bool viaTLS, HeaderContainer headerContainer, HttpContentStream contentStream)
        {
            RequestMethodName = requestMethodName;
            RequestUri = requestUri;
            HttpVersion = httpVersion;
            Headers = headerContainer;
            ViaTLS = viaTLS;
            ContentStream = contentStream;

            Initialize();
        }

        //private static Regex reHostPort = new Regex("(?<host>(\\w[^:]*|\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}|\\[\\]]+))(:(?<port>\\d+))?");

        void Initialize()
        {
            if (Enum.TryParse(RequestMethodName, out HttpMethod httpMethod))
                Method = httpMethod;
            else
                Method = HttpMethod.NONE;

            if (Headers.TryGetValue("Host", out string host))
            {
                int colon = host.LastIndexOf(':');
                if (colon != -1)
                {
                    Host = host.Substring(0, colon).Trim();
                    Port = int.Parse(host.Substring(colon + 1).Trim());
                }
                else
                {
                    Host = host.Trim();
                }
            } else
            {
                Host = RequestUri.Host;
                Port = RequestUri.Port;
            }

/*
            if (Headers.TryGetValue("X-Forwarded-Host", out string forwardedHost))
                host = forwardedHost;
            if (Headers.TryGetValue("X-Forwarded-For", out string forwardedFor))
                ClientAddress = IPAddress.Parse(forwardedFor.ReadToken(','));
            if (Headers.TryGetValue("X-Forwarded-Proto", out string forwardedProto))
                TLS = forwardedProto.Equals("https");

            if (Headers.TryGetValue("Forwarded", out string forwarded))
            {
                // ToDo: Implement parser
            }
*/
            BaseUri = new UriBuilder(ViaTLS ? "https:" : "http:", Host, Port).Uri;
            RequestUri = new Uri(BaseUri, RequestUri);
            Query = new QueryStringParameters(RequestUri.Query);
            
            requestCookies = new Dictionary<string, string>();
            
            if (Headers.TryGetValue("Cookie", out string cookies))
                SetupCookies(cookies);
        }
        
        private void SetupCookies(string cookies)
        {
            foreach (String cookie in cookies.Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries))
            {
                string[] c = cookie.Split(new char[] { '=' }, 2);
                string cn, cv;
                cn = c[0].Trim();
                if (c.Length > 1)
                    cv = c[1].Trim();
                else
                    cv = "";

                if (!this.requestCookies.ContainsKey(cn))
                    this.requestCookies.Add(cn, cv);
            }
        }

        public override string ToString() =>
            $"[HttpRequest: Host={Host} Port={Port} HttpVersion={HttpVersion} Method={Method} URI={RequestUri} Query={Query}]";

        public String GetRequestHeader(String name)
        {
            return GetRequestHeader(name, "");
        }

        public String GetRequestHeader(String name, String def)
        {
            if (Headers.TryGetValue(name, out string value))
                return value;
            return def;
        }

        public String[] CookieNames => requestCookies.Keys.ToArray();
        public bool ContainsCookie(String name) => this.requestCookies.ContainsKey(name);
        public String GetCookie(String name) => requestCookies[name];

        public bool TryGetCookie(string cookieName, out string cookieValue) =>
            requestCookies.TryGetValue(cookieName, out cookieValue);
        
        public HttpResponse Redirect(string location, params object[] p) => Redirect(HttpStatusCode.SeeOther, location, p);

        public HttpResponse Redirect(HttpStatusCode statusCode, string location, params object[] p)
        {
            if (p?.Length > 0)
                location = string.Format(location, p);

            HttpResponse response = new HttpResponse(statusCode);
            response.SetHeader("Location", location);
            return response;
        }

        public JSONValue ToJsonValue()
        {
            long p = ContentStream.Position;
            try
            {
                using (TextReader reader = new StreamReader(ContentStream))
                    return JSONParser.Parse(reader);
            }
            finally
            {
                ContentStream.Position = p;
            }
        }

        private string? _bodyText;
        public string Text
        {
            get
            {
                if (_bodyText is null)
                    _bodyText = Encoding.UTF8.GetString(ContentStream.ReadToEnd());
                return _bodyText;
            }
        }
        
        private JObject? _jobject;
        public JObject Json()
        {
            if (_jobject is null)
                _jobject = JObject.Load(new JsonTextReader(new StringReader(Text)));
            return _jobject;
        }

        public T Json<T>() => JsonConvert.DeserializeObject<T>(Text);
        public object Json(Type nativeType) => JsonConvert.DeserializeObject(Text, nativeType);


        public void Dispose() => ContentStream?.Dispose();
    }
}