Disassembled additional Inventory methods

1 files changed, 88 insertions, 46 deletions

diff --git a/engine/items/inventory.asm b/engine/items/inventory.asm
index 1f468d4..eb0ff51 100755
--- a/engine/items/inventory.asm
+++ b/engine/items/inventory.asm
@@ -4,12 +4,12 @@ SECTION "AddItemToInventory_", ROMX[$4AA1], BANK[$03]
 

 _ReceiveItem: ; 03:4AA1

 	call DoesHLEqualwNumBagItems

-	jp nz, PutItemInPocket ; not bag (so it's the pc)

+	jp nz, PutItemInPocket ; If its not bag, then its the PC, so jump down

 	push hl

 	ld hl, CheckItemPocket

 	ld a, BANK( CheckItemPocket )

 	call FarCall_hl

-	ld a, [wItemAttributeParamBuffer]

+	ld a, [wItemAttributeParamBuffer] ; a = PocketType

 	dec a

 	ld hl, .Pockets

 	jp CallJumptable

@@ -39,17 +39,17 @@ _ReceiveItem: ; 03:4AA1
 	pop hl

 	ld a, [wCurItem]

 	ld c, a

-	call GetTMHMNumber

-	jp ReceiveTMHM

+	call GetTMHMNumber ; get the index of the TMHM being added

+	jp ReceiveTMHM ; increase the quantity at that index

 	

 _TossItem: ; 03:4AE0

 	call DoesHLEqualwNumBagItems

-	jr nz, .removeItem

+	jr nz, .removeItem ; If its not bag, then its the PC, so jump down

 	push hl

 	ld hl, CheckItemPocket

 	ld a, BANK( CheckItemPocket )

 	call FarCall_hl

-	ld a, [wItemAttributeParamBuffer]

+	ld a, [wItemAttributeParamBuffer] ; a = PocketType

 	dec a

 	ld hl, .Pockets

 	jp CallJumptable

@@ -60,32 +60,72 @@ _TossItem: ; 03:4AE0
 	dw .Ball

 	dw .TMHM

 	

-.Ball

+.Ball ; 03:4B00

 	pop hl

 	ld a, [wCurItem]

 	ld c, a

-	call GetBallIndex

-	jp TossBall

+	call GetBallIndex ; get the index of the ball being removed

+	jp TossBall ; and decrease the quantity at that index

 	

-.TMHM

+.TMHM ; 03:4B0B

 	pop hl

 	ld a, [wCurItem]

 	ld c, a

-	call GetTMHMNumber

-	jp TossTMHM

+	call GetTMHMNumber ; get the index of the TMHM being removed

+	jp TossTMHM ; and decrease the quantity at that index

 	

-.KeyItem

+.KeyItem ; 03:4B16

 	pop hl

 	jp TossKeyItem

 	

-.Item

+.Item ; 03:4B1A

 	pop hl

 

-.removeItem

+.removeItem ; 03:4B1B

 	jp RemoveItemFromPocket

 

-SECTION "DoesHLEqualwNumBagItems", ROMX[$4B5C], BANK[$03]

+_CheckItem:: ; 03:4B1E

+	call DoesHLEqualwNumBagItems

+	jr nz, .checkItem ; If its not bag, then its the PC, so jump down

+	push hl

+	ld hl, CheckItemPocket

+	ld a, BANK( CheckItemPocket )

+	call FarCall_hl

+	ld a, [wItemAttributeParamBuffer] ; a = PocketType

+	dec a

+	ld hl, .Pockets

+	jp CallJumptable

+	

+.Pockets ; 03:4B36

+	dw .Item

+	dw .KeyItem

+	dw .Ball

+	dw .TMHM

+	

+.Ball ; 03:4B3E

+	pop hl

+	ld a, [wCurItem]

+	ld c, a

+	call GetBallIndex ; get the index of the ball being checked

+	jp CheckBall ; and check that index

+

+.TMHM ; 03:4B49

+	pop hl

+	ld a, [wCurItem]

+	ld c, a

+	call GetTMHMNumber ; get the index of the TMHM being checked

+	jp CheckTMHM ; and check that index

 	

+.KeyItem ; 03:4B54

+	pop hl

+	jp CheckKeyItems

+	

+.Item ; 03:4B58

+	pop hl

+	

+.checkItem

+	jp CheckTheItem

+

 ; Zero flag is set if hl = wNumBagItems

 DoesHLEqualwNumBagItems: ; 03:4B5C

 	ld a, l

@@ -97,36 +137,37 @@ DoesHLEqualwNumBagItems: ; 03:4B5C
 

 PutItemInPocket: ; 03:4B64

 	ld d, h

-	ld e, l ; de = pc inventory address

+	ld e, l ; de = address of start of inventory

 	inc hl

 	ld a, [wCurItem]

 	ld c, a

-	ld b, 0

+	ld b, 0 ; b = available space for slots already containing this item, initialize to 0

 	

 .findItemLoop

 	ld a, [hli]

 	cp $FF ; was the end of the list reached?

-	jr z, .checkIfInventoryFull ; if so, check if it can be added to the end

+	jr z, .checkIfInventoryFull ; if so, see if there are empty slots

 	cp c ; does the item match?

 	jr nz, .checkNextItem ; if not, move to the next item

 	ld a, 99 ; max amount of an item

-	sub [hl] ; subtract the current amount of items, so a = max number that can be added

-	add b ; ? why is this done? b = 0

-	ld b, a ; b = max number of items which can be added

-	ld a, [wItemQuantity]

-	cp b ; compare the to-add quantity to the max quantity

-	jr z, .itemCanBeAdded  ; if the number is equal, then add the item

-	jr c, .itemCanBeAdded  ; if the number is less than the max, then add the item

+	sub [hl] ; subtract the current amount of items, so a = the available space for this item slot

+	add b ; combine with the available space from previous slots for this item, so a = the total available space in all slots for this item

+	ld b, a ; store the total available space into b (for future iterations)

+	ld a, [wItemQuantity] ; a = quantity to add

+	cp b ; compare the quantity to add to the available space

+	jr z, .itemCanBeAdded  ; if the numbers are equal, then add the item

+	jr c, .itemCanBeAdded  ; if the number to add is less than the available space, then add the item

 

 .checkNextItem

 	inc hl ; move to the next item in the list

 	jr .findItemLoop

 	

 .checkIfInventoryFull

-	call GetPocketCapacity

+	call GetPocketCapacity ; c = maximum size for this inventory

 	ld a, [de] ; get the current size of the inventory

 	cp c ; compare to the maximum

 	jr c, .itemCanBeAdded ; if its not at the maximum, then an item can be added

+	

 	and a ; unset the carry flag to indicate failure

 	ret

 	

@@ -148,7 +189,7 @@ PutItemInPocket: ; 03:4B64
 	add [hl] ; a = new item quantity

 	cp a, 100 ; does it exceed 99?

 	jr nc, .setMax ; if it exceeds, then only increase quantity to the max

-	ld [hl], a ; store the new item quantity

+	ld [hl], a ; otherwise, store the new item quantity

 	jr .success

 

 ; set the inventory quantity to 99, and then add the remainder to the list

@@ -197,12 +238,12 @@ RemoveItemFromPocket: ;03:4BCF
 	add hl, bc ; hl = address of item at given index

 	inc hl

 	ld a, [wItemQuantity]

-	ld b, a ; b = to-remove amount

+	ld b, a ; b = amount to remove

 	ld a, [hl] ; a = current amount

-	sub b ; a = new amount

+	sub b ; a = remaining amount

 	jr c, .fail ; if trying to remove too many, then fail

 	

-	ld [hl],a ; store new amount

+	ld [hl], a ; store new amount

 	ld [wItemQuantityBuffer], a

 	and a ; is the new amount 0?

 	jr nz, .success ; if not, then dont shift items upwards

@@ -218,7 +259,7 @@ RemoveItemFromPocket: ;03:4BCF
 	ld [bc], a

 	inc bc ; overwrite the previous item value with the next item value

 	cp $FF ; reached the end of the list?

-	jr nz, .shift ; if not, shift the next row

+	jr nz, .shift ; if not, shift the next value

 	

 	ld h, d

 	ld l, e ; hl = inventory size

@@ -260,7 +301,7 @@ ReceiveKeyItem: ; 03:4C0E
 	jr nc, .fail ; then fail

 	ld c, a

 	ld b, 0

-	add hl, bc ; hl = address to store the item, end if the list

+	add hl, bc ; hl = address to store the item ( the end of the list )

 	ld a, [wCurItem]

 	ld [hli], a ; store item ID

 	ld [hl], $FF ; store terminator

@@ -364,8 +405,8 @@ BallItems: ; 03:4C73
 	

 

 ; To empty out the ball pocket

-; TODO - Is this buggy?

-; The ball pocket just is a set length, not $FF terminated

+; Note - Is this buggy?

+; The ball pocket is a fixed length, not $FF terminated

 EmptyBallPocket: ; 03:4C78

 	ld hl, wNumBallItems

 	xor a

@@ -373,7 +414,7 @@ EmptyBallPocket: ; 03:4C78
 	ld [hl], $FF ; add terminator

 	ret

 	

-; The Ball pocket is just a list of quantities, which directly map to BallItems

+; The Ball pocket is a list of quantities, which directly map to BallItems

 ; c = item index in table

 ; wItemQuantity = amount to add

 ; Sets carry flag if successful

@@ -381,13 +422,13 @@ ReceiveBall: ; 03:4C80
 	ld hl, wBallQuantities

 	ld b, 0

 	add hl, bc ; hl = address of item quantity in table

-	ld a, [wItemQuantity]

-	add [hl] ; add the current item quantity to the to-add quantity

+	ld a, [wItemQuantity] ; a = quantity to add

+	add [hl] ; combine with the current quantity, so a = new quantity

 	cp 100 ; does it exceed 99?

 	jr nc, .fail ; if so, fail

 	ld b, a ; b = new quantity

-	ld a, [hl] ; a = old quantity

-	and a ; is old quantity zero?

+	ld a, [hl] ; a = current quantity

+	and a ; is current quantity zero?

 	jr nz, .dontIncreaseInventorySize ; if not, dont increase the inventory size

 	ld a, [wNumBallItems]

 	inc a

@@ -411,11 +452,12 @@ TossBall: ; 03:4C9F
 	ld b, 0

 	add hl, bc ; hl = index for this item

 	ld a, [wItemQuantity]

-	ld b, a ; b = to-remove quantity

-	ld a, [hl] ; a = old quantity 

-	sub b ; a = new quantity

-	jr c, .fail ; if to-remove exceeds the current quantity, then fail

+	ld b, a ; b = quantity to remove

+	ld a, [hl] ; a = current quantity 

+	sub b ; a = remaining quantity

+	jr c, .fail ; if quantity to remove exceeds the current quantity, then fail

 	jr nz, .dontDecreaseInventorySize ; if the new quantity is not 0, then dont decrease the inventory size

+	

 	ld b, a

 	ld a, [wNumBallItems]

 	dec a

@@ -435,7 +477,7 @@ TossBall: ; 03:4C9F
 ; Inputs

 ; c = index of item

 ; Outputs

-; carry if item is in list

+; carry if ball has a non zero quantity

 CheckBall: ; 03:4CC0

 	ld hl, wBallQuantities

 	ld b, 0

@@ -472,7 +514,7 @@ TossTMHM: ; 03:4CDE
 	ld a, [wItemQuantity]

 	ld b, a ; b = amount to remove

 	ld a, [hl] ; a = current amount

-	sub b ; get the new amount

+	sub b ; a = remaining amount

 	jr c, .fail ; if the amount to remove exceeds the current amount, then fail

 	ld [hl], a ; store the new item count

 	ld [wItemQuantityBuffer], a