Decomp GetExclusiveItemOffsetEnsureValid

asm/include/main_0200CAFC.inc

@@ -25,6 +25,7 @@
 .public CopyBitsFrom
 .public CopyBitsTo
 .public GetDungeonGroup
+.public GetExclusiveItemOffsetEnsureValid
 .public GetItemActionName
 .public GetItemBuyPrice
 .public GetItemCategory

asm/main_0200CAFC.s

@@ -1889,27 +1889,3 @@ GetExclusiveItemType: ; 0x0200E760
 	.align 2, 0
 _0200E778: .word ITEM_DATA_TABLE_PTRS
 	arm_func_end GetExclusiveItemType
-
-	arm_func_start GetExclusiveItemOffsetEnsureValid
-GetExclusiveItemOffsetEnsureValid: ; 0x0200E77C
-	stmdb sp!, {r4, lr}
-	mov r4, r0
-	cmp r4, #0x1bc
-	blt _0200E798
-	ldr r1, _0200E7BC ; =0x00000578
-	cmp r4, r1
-	blt _0200E7A0
-_0200E798:
-	mov r0, #0x55
-	ldmia sp!, {r4, pc}
-_0200E7A0:
-	bl IsItemValid
-	cmp r0, #0
-	subne r0, r4, #0x1bc
-	movne r0, r0, lsl #0x10
-	movne r0, r0, asr #0x10
-	moveq r0, #0x55
-	ldmia sp!, {r4, pc}
-	.align 2, 0
-_0200E7BC: .word 0x00000578
-	arm_func_end GetExclusiveItemOffsetEnsureValid

include/item_util_1.h

@@ -3,6 +3,8 @@
 
 #include "util.h"
 
+s16 GetExclusiveItemOffsetEnsureValid(s16 item_id);
+
 // Checks if an item is valid given its ID.
 // In particular, checks if the "is valid" flag is set on its item_p.bin entry.
 bool8 IsItemValid(s16 item_id);

src/item_util_1.c

@@ -3,6 +3,16 @@
 
 extern struct item_data_entry *ITEM_DATA_TABLE_PTRS[3];
 
+s16 GetExclusiveItemOffsetEnsureValid(s16 item_id) {
+    if (item_id < ITEM_PRISM_RUFF || item_id >= NUM_ITEM_IDS) {
+        return ITEM_PLAIN_SEED;
+    }
+    if (IsItemValid(item_id)) {
+        return (s16)(item_id - ITEM_PRISM_RUFF);
+    }
+    return ITEM_PLAIN_SEED;
+}
+
 bool8 IsItemValid(s16 item_id)
 {
     if (ITEM_DATA_TABLE_PTRS[ITEM_DATA_TABLE_PTRS_INDEX][item_id].flags & ITEM_DATA_FLAG_VALID)