1 files changed, 91 insertions, 2 deletions

diff --git a/src/battle_tower.c b/src/battle_tower.c
index e70d4af91..a6983897f 100644
--- a/src/battle_tower.c
+++ b/src/battle_tower.c
@@ -4,16 +4,24 @@
 #include "overworld.h"
 #include "random.h"
 #include "battle_tower.h"
+#include "battle_frontier_1.h"
+#include "constants/battle_frontier.h"
 
 extern void sub_81A3ACC(void);
+extern u8 GetFrontierEnemyMonLevel(u8);
 
 extern const u32 gUnknown_085DF9AC[][2];
 extern const u32 gUnknown_085DF9CC[][2];
 extern void (* const gUnknown_085DF96C[])(void);
+extern const u8 gUnknown_085DF9F6[];
+extern const u8 gUnknown_085DF9EC[];
 
 // This file's functions.
 void sub_8164ED8(void);
-u16 sub_8164FCC(u8, u8);
+void sub_8163E90(void);
+void sub_8165B20(void);
+u16 GetCurrentBattleTowerWinStreak(u8 lvlMode, u8 battleMode);
+void sub_816534C(void *);
 
 // code
 void sub_8161F74(void)
@@ -49,7 +57,7 @@ void sub_8162054(void)
     case 0:
         break;
     case 1:
-        gSpecialVar_Result = sub_8164FCC(lvlMode, battleMode);
+        gSpecialVar_Result = GetCurrentBattleTowerWinStreak(lvlMode, battleMode);
         break;
     case 2:
         gSpecialVar_Result = ((gSaveBlock2Ptr->frontier.field_CDC & gUnknown_085DF9AC[battleMode][lvlMode]) != 0);
@@ -83,3 +91,84 @@ void sub_81620F4(void)
         break;
     }
 }
+
+void sub_81621C0(void)
+{
+    if (gTrainerBattleOpponent_A == 500)
+        sub_816534C(&gSaveBlock2Ptr->frontier.filler_BEC);
+
+    if (gSaveBlock2Ptr->frontier.field_D04 < 9999)
+        gSaveBlock2Ptr->frontier.field_D04++;
+
+    gSaveBlock2Ptr->frontier.field_CB2++;
+    sub_8163E90();
+    gSpecialVar_Result = gSaveBlock2Ptr->frontier.field_CB2;
+}
+
+bool8 ChooseSpecialBattleTowerTrainer(void)
+{
+    s32 i, j, validMons;
+    s32 trainerIds[9];
+    s32 idsCount = 0;
+    s32 winStreak = 0;
+    u8 lvlMode = gSaveBlock2Ptr->frontier.lvlMode;
+    u8 battleMode = VarGet(VAR_FRONTIER_BATTLE_MODE);
+
+    if (VarGet(VAR_FRONTIER_FACILITY) != FRONTIER_FACILITY_TOWER)
+        return FALSE;
+
+    winStreak = GetCurrentBattleTowerWinStreak(lvlMode, battleMode);
+    for (i = 0; i < 5; i++)
+    {
+        u32 *record = (u32*)(&gSaveBlock2Ptr->frontier.records[i]);
+        u32 recordHasData = 0;
+        u32 checksum = 0;
+        for (j = 0; j < (sizeof(struct EmeraldBattleTowerRecord) - 4) / 4; j++) // - 4, because of the last field being the checksum itself.
+        {
+            recordHasData |= record[j];
+            checksum += record[j];
+        }
+        validMons = 0;
+        for (j = 0; j < 4; j++)
+        {
+            if (gSaveBlock2Ptr->frontier.records[i].party[j].species != 0
+                && gSaveBlock2Ptr->frontier.records[i].party[j].level <= GetFrontierEnemyMonLevel(lvlMode))
+                validMons++;
+        }
+
+        if (validMons >= gUnknown_085DF9F6[battleMode]
+            && gSaveBlock2Ptr->frontier.records[i].winStreak == winStreak
+            && gSaveBlock2Ptr->frontier.records[i].lvlMode == lvlMode
+            && recordHasData
+            && gSaveBlock2Ptr->frontier.records[i].checksum == checksum)
+        {
+            trainerIds[idsCount] = i + BATTLE_TOWER_RECORD_MIXING_TRAINER_BASE_ID;
+            idsCount++;
+        }
+    }
+
+    if (battleMode == FRONTIER_MODE_SINGLES)
+    {
+        sub_8165B20();
+        for (i = 0; i < 4; i++)
+        {
+            if (gSaveBlock2Ptr->apprentices[i].lvlMode != 0
+                && gUnknown_085DF9EC[gSaveBlock2Ptr->apprentices[i].field_1] == winStreak
+                && gSaveBlock2Ptr->apprentices[i].lvlMode - 1 == lvlMode)
+            {
+                trainerIds[idsCount] = i + BATTLE_TOWER_RECORD_APPRENTICE_BASE_ID;
+                idsCount++;
+            }
+        }
+    }
+
+    if (idsCount != 0)
+    {
+        gTrainerBattleOpponent_A = trainerIds[Random() % idsCount];
+        return TRUE;
+    }
+    else
+    {
+        return FALSE;
+    }
+}