From f64d31c557eb15dfdba54b17576603621f0ed834 Mon Sep 17 00:00:00 2001
From: Kurt <kaphotics@gmail.com>
Date: Sun, 5 Feb 2017 10:57:42 -0800
Subject: [PATCH] Faster G7TID generation

#823

generate a random T7SID instead of brute forcing a pair
---
 .../Save Editors/Gen7/SAV_Trainer7.cs         | 32 ++-----------------
 PKHeX/Saves/SaveUtil.cs                       | 27 ++++++++++++++++
 2 files changed, 30 insertions(+), 29 deletions(-)

diff --git a/PKHeX.WinForms/Subforms/Save Editors/Gen7/SAV_Trainer7.cs b/PKHeX.WinForms/Subforms/Save Editors/Gen7/SAV_Trainer7.cs
index f33f69a6a..06cbe8684 100644
--- a/PKHeX.WinForms/Subforms/Save Editors/Gen7/SAV_Trainer7.cs	
+++ b/PKHeX.WinForms/Subforms/Save Editors/Gen7/SAV_Trainer7.cs	
@@ -389,35 +389,9 @@ namespace PKHeX.WinForms
 
         private void B_GenTID_Click(object sender, EventArgs e)
         {
-            B_GenTID.Text = "Generating";
-            B_GenTID.Enabled = false;
-            int final, i_TID, i_SID;
-            Random random = new Random();
-            i_TID = random.Next(0, 65535);
-            bool matchFound = false;
-
-            while (!matchFound)
-            {
-                i_SID = 0;
-
-                while (i_SID < 65535 && !matchFound)
-                {
-                    final = i_TID + (i_SID * 65536) % 1000000;
-
-                    if (final == int.Parse(MT_G7TID.Text))
-                    {
-                        MT_TID.Text = i_TID.ToString();
-                        MT_SID.Text = i_SID.ToString();
-                        matchFound = true;
-                        B_GenTID.Text = "Generate";
-                        B_GenTID.Enabled = true;
-                    }
-
-                    i_SID++;
-                }
-
-                i_TID = (i_TID == 65535) ? 0 : i_TID + 1;
-            }
+            var tuple = SaveUtil.getTIDSID(Util.ToUInt32(MT_G7TID.Text), ModifierKeys == Keys.Control);
+            MT_TID.Text = tuple.Item1.ToString("D5");
+            MT_SID.Text = tuple.Item2.ToString("D5");
         }
 
         private readonly Dictionary<int, string> RecordList = new Dictionary<int, string>
diff --git a/PKHeX/Saves/SaveUtil.cs b/PKHeX/Saves/SaveUtil.cs
index 48282469c..67648f2c9 100644
--- a/PKHeX/Saves/SaveUtil.cs
+++ b/PKHeX/Saves/SaveUtil.cs
@@ -975,5 +975,32 @@ namespace PKHeX.Core
 
             return keys;
         }
+
+        /// <summary>
+        /// Creates a 16bit TID/SID tuple for a given G7TID.
+        /// </summary>
+        /// <param name="G7TID">Desired G7TID</param>
+        /// <param name="minimizeSID">Optional param to yield minimum SID.</param>
+        /// <returns>16bit TID/SID tuple</returns>
+        public static Tuple<uint, uint> getTIDSID(uint G7TID, bool minimizeSID = false)
+        {
+            // 32 bit number = 4294 967295
+            // lowest 6 digits G7TID
+
+            // Bare minimum 32bit value to get ID, yields min SID
+            uint val = G7TID;
+            if (!minimizeSID) // randomize SID
+            {
+                uint s7 = 4294;
+                if (val > 967295)
+                    s7 -= 1;
+                s7 = (uint)Util.rand.Next(0, (int)s7);
+                val += s7 * 1000000;
+            }
+            uint TID = val & 0xFFFF;
+            uint SID = val >> 16;
+
+            return new Tuple<uint, uint>(TID, SID);
+        }
     }
 }