using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace HTTPServer
{
    public enum RequestMethod
    {
        GET,
        POST,
        HEAD
    }

    public enum HTTPVersion
    {
        HTTP10,
        HTTP11,
        HTTP09
    }

    class Request
    {
        string[] requestLines;
        RequestMethod method;
        public string relativeURI;
        Dictionary<string, string> headerLines;

        public Dictionary<string, string> HeaderLines
        {
            get { return headerLines; }
        }

        HTTPVersion httpVersion;
        string requestString;
        string[] contentLines;

        public Request(string requestString)
        {
            this.requestString = requestString;
        }
        /// <summary>
        /// Parses the request string and loads the request line, header lines and content, returns false if there is a parsing error
        /// </summary>
        /// <returns>True if parsing succeeds, false otherwise.</returns>
        public bool ParseRequest()
        {
            //TODO: parse the receivedRequest using the \r\n delimeter
            requestLines = requestString.Split('\n');   //Msh rady y-split xD

            // check that there is atleast 3 lines: Request line, Host Header, Blank line (usually 4 lines with the last empty line for empty content)


            // Validate blank line exists

            // Load header lines into HeaderLines dictionary
            return (ValidateBlankLine() && ParseRequestLine() && LoadHeaderLines());

        }

        private bool ParseRequestLine()
        {
            bool parsed = false;
            bool HTTP = false;
            string request = requestLines[0];
            string[] get = request.Split(' ');
            if (get[0] == "GET")
            {
                method = RequestMethod.GET;
                parsed = true;
            }
            else if (get[0] == "POST")
            {
                method = RequestMethod.POST;
                parsed = true;
            }
            else if (get[0] == "HEAD")
            {
                method = RequestMethod.HEAD;
                parsed = true;
            }

            // Parse Request line
            relativeURI = get[1];
            if (get[2] == "HTTP09")
            {
                httpVersion = HTTPVersion.HTTP09;
                HTTP = true;
            }
            else if (get[2] == "HTTP10")
            {
                httpVersion = HTTPVersion.HTTP10;
                HTTP = true;
            }
            else if (get[2] == "HTTP11")
            {
                httpVersion = HTTPVersion.HTTP11;
                HTTP = true;
            }
            return parsed & HTTP;
        }

        private bool ValidateIsURI(string uri)
        {
            return Uri.IsWellFormedUriString(uri, UriKind.RelativeOrAbsolute);
        }

        private bool LoadHeaderLines()
        {
            int counter = 1;
            bool Loaded = false;
            while (requestLines[counter] != "\r\n")
            {
                string[] headrs = requestLines[counter].Split(':');
                headerLines.Add(headrs[0], headrs[1]);
                counter++;
                Loaded = true;
            }
            return Loaded;
        }

        private bool ValidateBlankLine()
        {
            for(int i=0;i<requestLines.Length;i++)
            {
                if (requestLines[i] == "\r\n")
                    return true;
            }
            return false;
        }

    }
}