Integration of the Mojang API (#1709)

* Add Mojang API integration

* Addition in MinecraftClient.csproj

* Move Mojang API to Protocol namespace

* Add changes of MinecraftClient.csproj

* Add rate limit warning

* Improve rate limit warning

MinecraftClient/Protocol/MojangAPI.cs

@@ -0,0 +1,146 @@
+using System;
+using System.Collections.Generic;
+using System.Net;
+
+/// !!! ATTENTION !!!
+/// By using these functions you agree to the ToS of the Mojang API.
+/// You should note that all public APIs are rate limited so you are expected to cache the results. 
+/// This is currently set at 600 requests per 10 minutes but this may change.
+/// !!! ATTENTION !!!
+
+namespace MinecraftClient.Protocol
+{
+    /// <summary>
+    /// Provides methods to easily interact with the Mojang API.
+    /// </summary>
+    public static class MojangAPI
+    {
+        // Initialize webclient for all functions
+        private static readonly WebClient wc = new WebClient();
+
+        // Can be removed in newer C# versions.
+        // Replace with DateTimeOffset.FromUnixTimeMilliseconds()
+        /// <summary>
+        /// Converts a Unix time to a normal Datetime
+        /// </summary>
+        /// <param name="unixTimeStamp">A unix timestamp as double</param>
+        /// <returns>Datetime of unix timestamp</returns>
+        private static DateTime unixTimeStampToDateTime(double unixTimeStamp)
+        {
+            // Unix timestamp is seconds past epoch
+            DateTime dateTime = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
+            dateTime = dateTime.AddMilliseconds(unixTimeStamp).ToLocalTime();
+            return dateTime;
+        }
+        // Can be removed in newer C# versions.
+
+        /// <summary>
+        /// Obtain the UUID of a Player through its name
+        /// </summary>
+        /// <param name="name">Playername</param>
+        /// <returns>UUID as string</returns>
+        public static string NameToUuid(string name)
+        {
+            try
+            {
+                return Json.ParseJson(wc.DownloadString("https://api.mojang.com/users/profiles/minecraft/" + name)).Properties["id"].StringValue;
+            }
+            catch (Exception) { return string.Empty; }
+        }
+
+        /// <summary>
+        /// Obtain the Name of a player through its UUID
+        /// </summary>
+        /// <param name="uuid">UUID of a player</param>
+        /// <returns>Players UUID</returns>
+        public static string UuidToCurrentName(string uuid)
+        {
+            // Perform web request
+            try
+            {
+                var nameChanges = Json.ParseJson(wc.DownloadString("https://api.mojang.com/user/profiles/" + uuid + "/names")).DataArray;
+
+                // Names are sorted from past to most recent. We need to get the last name in the list
+                return nameChanges[nameChanges.Count - 1].Properties["name"].StringValue;
+            }
+            catch (Exception) { return string.Empty; }
+        }
+
+        /// <summary>
+        /// Get the name history from a UUID
+        /// </summary>
+        /// <param name="uuid">UUID of a player</param>
+        /// <returns>Name history, as a dictionary</returns>
+        public static Dictionary<string, DateTime> UuidToNameHistory(string uuid)
+        {
+            Dictionary<string, DateTime> tempDict = new Dictionary<string, DateTime>();
+            List<Json.JSONData> jsonDataList;
+
+            // Perform web request
+            try
+            {
+                jsonDataList = Json.ParseJson(wc.DownloadString("https://api.mojang.com/user/profiles/" + uuid + "/names")).DataArray;
+            }
+            catch (Exception) { return tempDict; }
+
+            foreach (Json.JSONData jsonData in jsonDataList)
+            {
+                if (jsonData.Properties.Count > 1)
+                {
+                    // Time is saved as long in the Unix format.
+                    // Convert it to normal time, before adding it to the dictionary.
+                    //
+                    // !! FromUnixTimeMilliseconds does not exist in the current version. !!
+                    // DateTimeOffset creationDate = DateTimeOffset.FromUnixTimeMilliseconds(Convert.ToInt64(jsonData.Properties["changedToAt"].StringValue));
+                    //
+
+                    // Workaround for converting Unix time to normal time
+                    DateTimeOffset creationDate = unixTimeStampToDateTime(Convert.ToDouble(jsonData.Properties["changedToAt"].StringValue));
+
+                    // Add Keyvaluepair to dict.
+                    tempDict.Add(jsonData.Properties["name"].StringValue, creationDate.DateTime);
+                }
+                // The first entry does not contain a change date.
+                else if (jsonData.Properties.Count > 0)
+                {
+                    // Add an undefined time to it.
+                    tempDict.Add(jsonData.Properties["name"].StringValue, new DateTime());
+                }
+            }
+
+            return tempDict;
+        }
+
+        /// <summary>
+        /// Get the Mojang API status
+        /// </summary>
+        /// <returns>Dictionary of the Mojang services</returns>
+        public static Dictionary<string, string> GetMojangServiceStatus()
+        {
+            Dictionary<string, string> tempDict = new Dictionary<string, string>();
+            List<Json.JSONData> jsonDataList;
+
+            // Perform web request
+            try
+            {
+                jsonDataList = Json.ParseJson(wc.DownloadString("https://status.mojang.com/check")).DataArray;
+            }
+            catch (Exception) { return tempDict; }
+
+            // Convert JSONData to string and parse it to a dictionary.
+            foreach (Json.JSONData jsonData in jsonDataList)
+            {
+                if (jsonData.Properties.Count > 0)
+                {
+                    foreach (KeyValuePair<string, Json.JSONData> keyValuePair in jsonData.Properties)
+                    {
+                        // Service name to status
+                        tempDict.Add(keyValuePair.Key, keyValuePair.Value.StringValue);
+                    }
+                }
+            }
+
+            return tempDict;
+        }
+    }
+}