using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Net;
using System.Text;
using System.Xml.Linq;
using System.Xml.XPath;
using LibGit2Sharp;

namespace TCBuildConfigSync
{
    /// <summary>
    /// Syncs TeamCity build configurations with Git branches.
    /// 
    /// Uses libgit2sharp to read the list of branches from Git, the TeamCity REST API and HTTP POSTs to the TeamCity dashboard URLs.
    ///
    /// libgit2sharp: https://github.com/libgit2/libgit2sharp
    /// </summary>
    class Program
    {
        private const string TeamCityUrl = "http://bob/httpAuth";

        static void Main(string[] args)
        {
            using (var repo = new Repository(args[0]))
            {
                // Collect all the TeamCity build configurations
                Dictionary<string, string> tcBranches = new Dictionary<string, string>(); // Name to Id map
                List<string> tcBranchesToDelete = new List<string>();
                using (WebClient webClient = GetWebClient())
                {
                    XDocument doc = XDocument.Parse(webClient.DownloadString(TeamCityUrl + "/app/rest/projects/id:project9"));

                    foreach (XElement buildTypeEl in doc.Root.XPathSelectElements("buildTypes/buildType"))
                    {
                        string id = buildTypeEl.Attribute("id").Value;
                        string name = buildTypeEl.Attribute("name").Value;
                        tcBranches.Add(name, id);
                        tcBranchesToDelete.Add(name);
                    }
                }

                // Collect all the branches in this repo
                foreach (Branch branch in repo.Branches)
                {
                    // Only look at remote branches
                    if (!branch.IsRemote) continue;

                    // Only look at private branches
                    if (!branch.Name.StartsWith("origin/private/")) continue;

                    string gitBranchName = branch.Name.Substring("origin/".Length);
                    string tcConfigName = branch.Name.Substring("origin/private/".Length).Replace('/', '-');

                    if (!tcBranches.ContainsKey(tcConfigName))
                    {
                        Console.ForegroundColor = ConsoleColor.Yellow;
                        Console.WriteLine("+" + tcConfigName);
                        Console.ResetColor();

                        // Create a new configuration for this branch
                        using (WebClient webClient = GetWebClient())
                        {
                            NameValueCollection parameters = new NameValueCollection();
                            parameters.Add("buildTypeName", tcConfigName);
                            parameters.Add("createFromTemplate", "Create");
                            parameters.Add("templateId", "btTemplate6");
                            parameters.Add("param:BRANCH_NAME", gitBranchName);
                            byte[] responseArray = webClient.UploadValues(TeamCityUrl + "/admin/action.html", "POST", parameters);
                            string response = Encoding.ASCII.GetString(responseArray);
                            Console.WriteLine(" ->" + response);
                        }
                    }
                    else
                    {
                        Console.ForegroundColor = ConsoleColor.Green;
                        Console.WriteLine(" " + tcConfigName);
                        Console.ResetColor();

                        // Remove branch from deletion list, there is a matching Git branch
                        tcBranchesToDelete.Remove(tcConfigName);
                    }
                }

                // Delete build configurations without Git branches
                foreach (string tcConfigName in tcBranchesToDelete)
                {
                    Console.ForegroundColor = ConsoleColor.Red;
                    Console.WriteLine("-" + tcConfigName);
                    Console.ResetColor();

                    // Delete this dead configuration
                    using (WebClient webClient = GetWebClient())
                    {
                        NameValueCollection parameters = new NameValueCollection();
                        parameters.Add("buildTypeId", tcBranches[tcConfigName]);
                        parameters.Add("removeBuildType", "1");
                        byte[] responseArray = webClient.UploadValues(TeamCityUrl + "/admin/action.html", "POST", parameters);
                        string response = Encoding.ASCII.GetString(responseArray);
                        Console.WriteLine(" -> " + response);
                    }
                }
            }
        }

        private static WebClient GetWebClient()
        {
            WebClient webClient = new WebClient();
            webClient.Credentials = new NetworkCredential("user", "password");
            return webClient;
        }
    }
}