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-rw-r--r--FireBase/FirebaseKeyGenerator.cs92
1 files changed, 0 insertions, 92 deletions
diff --git a/FireBase/FirebaseKeyGenerator.cs b/FireBase/FirebaseKeyGenerator.cs
deleted file mode 100644
index acad399..0000000
--- a/FireBase/FirebaseKeyGenerator.cs
+++ /dev/null
@@ -1,92 +0,0 @@
-namespace Firebase.Database
-{
- using System;
- using System.Text;
-
- /// <summary>
- /// Offline key generator which mimics the official Firebase generators.
- /// Credit: https://github.com/bubbafat/FirebaseSharp/blob/master/src/FirebaseSharp.Portable/FireBasePushIdGenerator.cs
- /// </summary>
- public class FirebaseKeyGenerator
- {
- // Modeled after base64 web-safe chars, but ordered by ASCII.
- private const string PushCharsString = "-0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz";
- private static readonly char[] PushChars;
- private static readonly DateTimeOffset Epoch = new DateTimeOffset(1970, 1, 1, 0, 0, 0, 0, TimeSpan.Zero);
-
- private static readonly Random random = new Random();
- private static readonly byte[] lastRandChars = new byte[12];
-
- // Timestamp of last push, used to prevent local collisions if you push twice in one ms.
- private static long lastPushTime;
-
- static FirebaseKeyGenerator()
- {
- PushChars = Encoding.UTF8.GetChars(Encoding.UTF8.GetBytes(PushCharsString));
- }
-
- /// <summary>
- /// Returns next firebase key based on current time.
- /// </summary>
- /// <returns>
- /// The <see cref="string"/>. </returns>
- public static string Next()
- {
- // We generate 72-bits of randomness which get turned into 12 characters and
- // appended to the timestamp to prevent collisions with other clients. We store the last
- // characters we generated because in the event of a collision, we'll use those same
- // characters except "incremented" by one.
- var id = new StringBuilder(20);
- var now = (long)(DateTimeOffset.Now - Epoch).TotalMilliseconds;
- var duplicateTime = now == lastPushTime;
- lastPushTime = now;
-
- var timeStampChars = new char[8];
- for (int i = 7; i >= 0; i--)
- {
- var index = (int)(now % PushChars.Length);
- timeStampChars[i] = PushChars[index];
- now = (long)Math.Floor((double)now / PushChars.Length);
- }
-
- if (now != 0)
- {
- throw new Exception("We should have converted the entire timestamp.");
- }
-
- id.Append(timeStampChars);
-
- if (!duplicateTime)
- {
- for (int i = 0; i < 12; i++)
- {
- lastRandChars[i] = (byte)random.Next(0, PushChars.Length);
- }
- }
- else
- {
- // If the timestamp hasn't changed since last push, use the same random number,
- // except incremented by 1.
- var lastIndex = 11;
- for (; lastIndex >= 0 && lastRandChars[lastIndex] == PushChars.Length - 1; lastIndex--)
- {
- lastRandChars[lastIndex] = 0;
- }
-
- lastRandChars[lastIndex]++;
- }
-
- for (int i = 0; i < 12; i++)
- {
- id.Append(PushChars[lastRandChars[i]]);
- }
-
- if (id.Length != 20)
- {
- throw new Exception("Length should be 20.");
- }
-
- return id.ToString();
- }
- }
-}