// ClassicalSharp copyright 2014-2016 UnknownShadow200 | Licensed under MIT
using System;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;

namespace Launcher.Web {

	/// <summary> Represents a task that performs a series of GET or POST requests asynchronously. </summary>
	public abstract class IWebTask {
		
		public virtual void ResetSession() {
			Username = null;
			cookies = new CookieContainer();
		}
		
		/// <summary> Whether this web task is still performing GET or POST requests asynchronously. </summary>
		public bool Working;
		
		/// <summary> Whether this web task has finished. </summary>
		public bool Done;
		
		/// <summary> Whether the web task finished with an error or not. </summary>
		public bool Success;
		
		/// <summary> Handled exception that was generated by the last GET or POST request. </summary>
		public WebException Exception;
		
		/// <summary> Current status of this web task (e.g. downloading page X) </summary>
		public string Status;
		
		/// <summary> Username used when performing GET or POST requests, can be left null. </summary>
		public string Username;
		
		protected void Finish(bool success, WebException ex, string status) {
			if (!success) 
				Username = null;
			Working = false;
			Done = true;
			Success = success;
			
			Exception = ex;
			Status = status;
		}
		
		protected CookieContainer cookies = new CookieContainer();
		
		protected HttpWebResponse MakeRequest(string uri, string referer, string data) {
			WebRequest.DefaultWebProxy = null;
			HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
			request.UserAgent = Program.AppName;
			request.ReadWriteTimeout = 90 * 1000;
			request.Timeout = 90 * 1000;
			request.Referer = referer;
			request.KeepAlive = true;
			request.CookieContainer = cookies;
			
			request.AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate;
			if (data != null) {
				request.Method = "POST";
				request.ContentType = "application/x-www-form-urlencoded; charset=UTF-8;";
				byte[] encodedData = Encoding.UTF8.GetBytes(data);
				request.ContentLength = encodedData.Length;
				using (Stream stream = request.GetRequestStream()) {
					stream.Write(encodedData, 0, encodedData.Length);
				}
			}
			return (HttpWebResponse)request.GetResponse();
		}
		
		protected IEnumerable<string> GetHtml(string uri, string referer) {
			HttpWebResponse response = MakeRequest(uri, referer, null);
			return GetResponseLines(response);
		}

		protected IEnumerable<string> PostHtml(string uri, string referer, string data) {
			HttpWebResponse response = MakeRequest(uri, referer, data);
			return GetResponseLines(response);
		}
		
		protected string GetHtmlAll(string uri, string referer) {
			HttpWebResponse response = MakeRequest(uri, referer, null);
			return GetResponseAll(response);
		}
		
		protected string PostHtmlAll(string uri, string referer, string data) {
			HttpWebResponse response = MakeRequest(uri, referer, data);
			return GetResponseAll(response);
		}
		
		protected IEnumerable<string> GetResponseLines(HttpWebResponse response) {
			using (Stream stream = response.GetResponseStream()) {
				using (StreamReader reader = new StreamReader(stream)) {
					string line;
					while ((line = reader.ReadLine()) != null) {
						yield return line;
					}
				}
			}
		}
		
		protected string GetResponseAll(HttpWebResponse response) {
			using (Stream stream = response.GetResponseStream()) {
				using (StreamReader reader = new StreamReader(stream)) {
					return reader.ReadToEnd();
				}
			}
		}
		
		protected static void Log(string text) {
			Console.WriteLine(text);
		}
	}
}