using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Xml;
using Newtonsoft.Json.Linq;
using RestSharp;

namespace ConsoleApplication3
{
    public class ApplicationInfo
    {
        public string ID { get; set; }
        public string AppTitle { get; set; }
        public string AppLaunchURL { get; set; }
        public string AppIcon { get; set; }
        public string AppDesc { get; set; }
    }

    public class AuthCredential
    {
        public string AuthToken { get; set; }
        public string SessionID { get; set; }
        public string CSRFToken { get; set; }
    }

    public class Proxy
    {
        public static AuthCredential Authenticate(string storeFrontUrl, string username, string password, string domain)
        {
            var isSsl = storeFrontUrl.ToLower().IndexOf("https:", StringComparison.Ordinal) != -1;
            var csrfToken = Guid.NewGuid().ToString();
            var aspnetSessionId = Guid.NewGuid().ToString();
            
            var request = new RestRequest("/PostCredentialsAuth/Login", Method.POST);
            request.AddHeader("X-Citrix-IsUsingHTTPS", isSsl ? "Yes" : "No");
            request.AddHeader("Content-Type", "application/x-www-form-urlencoded");
            request.AddHeader("Csrf-Token", csrfToken);
            request.AddCookie("csrtoken", csrfToken);
            request.AddCookie("asp.net_sessionid", aspnetSessionId);

            var authenticationBody = string.Format("username={0}\\{1}&password={2}", domain, username, password);
            request.AddParameter("application/x-www-form-urlencoded", authenticationBody, ParameterType.RequestBody);

            var client = new RestClient(storeFrontUrl);
            //set the cookie container
            client.CookieContainer = new System.Net.CookieContainer();
            var response = client.Execute(request);
            if (response.ResponseStatus == ResponseStatus.Error)
            {
                throw new Exception(string.Format("Error: {0}", response.ErrorMessage));
            }

            //parse cookie values
            var returnedContent = response.Content;
            var doc = new XmlDocument();
            doc.LoadXml(returnedContent);

            var statusNodeList = doc.GetElementsByTagName("Result");
            if (statusNodeList.Count != 1) return null;
            if (statusNodeList[0].InnerText.ToLower() != "success") return null;

            //Restsharp is not returning the headers correctly. So let's parse them manually through the header property
            var returnedValues = new Dictionary<string, string>();
            foreach (var header in response.Headers.Where(i => i.Name == "Set-Cookie"))
            {
                var cookieValues = header.Value.ToString().Split(',');
                foreach (string cookieValue in cookieValues)
                {
                    var cookieElements = cookieValue.Split(';');
                    var keyValueElements = cookieElements[0].Split('=');
                    returnedValues.Add(keyValueElements[0], keyValueElements[1]);
                }
            }

            var credentials = new AuthCredential
            {
                AuthToken = returnedValues["CtxsAuthId"],
                CSRFToken = returnedValues["CsrfToken"],
                SessionID = returnedValues["ASP.NET_SessionId"]
            };
            return credentials;
        }
        
        public static List<ApplicationInfo> GetResources(string storeFrontUrl, AuthCredential credentials)
        {
            var isSsl = storeFrontUrl.ToLower().IndexOf("https:", StringComparison.Ordinal) != -1;
            var request = new RestRequest(@"Resources/List", Method.POST);
            request.AddHeader("X-Citrix-IsUsingHTTPS", isSsl ? "Yes" : "No");
            request.AddHeader("Accept", "application/json");
            request.AddHeader("Csrf-Token", credentials.CSRFToken);
            request.AddCookie("csrftoken", credentials.CSRFToken);
            request.AddCookie("asp.net_sessionid", credentials.SessionID);
            request.AddCookie("CtxsAuthId", credentials.AuthToken);

            var client = new RestClient(storeFrontUrl);
            var resourceList = client.Execute(request);
            var json = resourceList.Content;
            var jsonObject = JObject.Parse(json);
            var resources = (JArray)jsonObject["resources"];

            var applicationList = new List<ApplicationInfo>();
            foreach (var resource in resources)
            {
                var appInfo = new ApplicationInfo();
                appInfo.AppTitle = resource["name"].ToString();
                try
                {
                    appInfo.AppDesc = resource["description"].ToString();
                }
                catch (Exception)
                {
                    appInfo.AppDesc = "";
                }
                appInfo.AppIcon = resource["iconurl"].ToString();
                appInfo.AppLaunchURL = resource["launchurl"].ToString();
                appInfo.ID = resource["id"].ToString();
                applicationList.Add(appInfo);
            }

            return applicationList;
        }

        public static string GetIca(string storeFrontUrl, AuthCredential credentials, ApplicationInfo appInfo)
        {
            var isSsl = storeFrontUrl.ToLower().IndexOf("https:", StringComparison.Ordinal) != -1;
            var request = new RestRequest(Method.GET);
            request.AddHeader("X-Citrix-IsUsingHTTPS", isSsl ? "Yes" : "No");
            request.AddHeader("Accept", "application/octet-stream");
            request.AddHeader("Csrf-Token", credentials.CSRFToken);
            request.AddCookie("csrftoken", credentials.CSRFToken);
            request.AddCookie("asp.net_sessionid", credentials.SessionID);
            request.AddCookie("CtxsAuthId", credentials.AuthToken);

            var applicationUrl = string.Format("{0}/{1}", storeFrontUrl, appInfo.AppLaunchURL);
            var client = new RestClient(applicationUrl);
            var icaResponse = client.Execute(request);
            var icaFile = icaResponse.Content;
            return icaFile;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            var storeFrontUrl = @"http://YourStoreFrontServerURL/Citrix/StoreWeb";
            var username = "YourUserName";
            var password = "YourPassword";
            var domain = "YourDomain";
            // Logs in to Citrix store front
            var credentials = Proxy.Authenticate(storeFrontUrl, username, password, domain);
            // Gets the list of resources for the user
            var _applications = Proxy.GetResources(storeFrontUrl, credentials);
            // Pick the first application in the list
            var app = _applications.First();
            // Generate the ICA File
            var _ica = Proxy.GetIca(storeFrontUrl, credentials, app);
            // Save the ICA file to disk
            var path = @"D:\temp";
            string _icaFile = string.Format(@"{0}/{1}.ica", path, app.AppTitle);
            if (File.Exists(_icaFile))
            {
                File.Delete(_icaFile);
            }
            File.WriteAllText(_icaFile, _ica, Encoding.UTF8);
        }
    }
}