Organize the engine/ directory, take 2

Renamed `game` to `games` and `menu` to `menus`.
Moved some functions from `engine/routines/` to their fitting subdirectories.

Made two new subdirectories:
* engine/rtc: Contains all RTC-related things. Menus, hardware, misc
functions.
* engine/items: Contains all item-related things. Pack, item effects,
other item handlers.

engine/items/buy_sell_toss.asm

@@ -0,0 +1,235 @@
+SelectQuantityToToss: ; 24fbf
+	ld hl, TossItem_MenuHeader
+	call LoadMenuHeader
+	call Toss_Sell_Loop
+	ret
+; 24fc9
+
+SelectQuantityToBuy: ; 24fc9
+	farcall GetItemPrice
+RooftopSale_SelectQuantityToBuy: ; 24fcf
+	ld a, d
+	ld [wBuffer1], a
+	ld a, e
+	ld [wBuffer2], a
+	ld hl, BuyItem_MenuHeader
+	call LoadMenuHeader
+	call Toss_Sell_Loop
+	ret
+; 24fe1
+
+SelectQuantityToSell: ; 24fe1
+	farcall GetItemPrice
+	ld a, d
+	ld [wBuffer1], a
+	ld a, e
+	ld [wBuffer2], a
+	ld hl, SellItem_MenuHeader
+	call LoadMenuHeader
+	call Toss_Sell_Loop
+	ret
+; 24ff9
+
+Toss_Sell_Loop: ; 24ff9
+	ld a, 1
+	ld [wItemQuantityChangeBuffer], a
+.loop
+	call BuySellToss_UpdateQuantityDisplay ; update display
+	call BuySellToss_InterpretJoypad       ; joy action
+	jr nc, .loop
+	cp -1
+	jr nz, .nope ; pressed B
+	scf
+	ret
+
+.nope
+	and a
+	ret
+; 2500e
+
+BuySellToss_InterpretJoypad: ; 2500e
+	call JoyTextDelay_ForcehJoyDown ; get joypad
+	bit B_BUTTON_F, c
+	jr nz, .b
+	bit A_BUTTON_F, c
+	jr nz, .a
+	bit D_DOWN_F, c
+	jr nz, .down
+	bit D_UP_F, c
+	jr nz, .up
+	bit D_LEFT_F, c
+	jr nz, .left
+	bit D_RIGHT_F, c
+	jr nz, .right
+	and a
+	ret
+
+.b
+	ld a, -1
+	scf
+	ret
+
+.a
+	ld a, 0
+	scf
+	ret
+
+.down
+	ld hl, wItemQuantityChangeBuffer
+	dec [hl]
+	jr nz, .finish_down
+	ld a, [wItemQuantityBuffer]
+	ld [hl], a
+
+.finish_down
+	and a
+	ret
+
+.up
+	ld hl, wItemQuantityChangeBuffer
+	inc [hl]
+	ld a, [wItemQuantityBuffer]
+	cp [hl]
+	jr nc, .finish_up
+	ld [hl], 1
+
+.finish_up
+	and a
+	ret
+
+.left
+	ld a, [wItemQuantityChangeBuffer]
+	sub 10
+	jr c, .load_1
+	jr z, .load_1
+	jr .finish_left
+
+.load_1
+	ld a, 1
+
+.finish_left
+	ld [wItemQuantityChangeBuffer], a
+	and a
+	ret
+
+.right
+	ld a, [wItemQuantityChangeBuffer]
+	add 10
+	ld b, a
+	ld a, [wItemQuantityBuffer]
+	cp b
+	jr nc, .finish_right
+	ld b, a
+
+.finish_right
+	ld a, b
+	ld [wItemQuantityChangeBuffer], a
+	and a
+	ret
+; 25072
+
+BuySellToss_UpdateQuantityDisplay: ; 25072
+	call MenuBox
+	call MenuBoxCoord2Tile
+	ld de, SCREEN_WIDTH + 1
+	add hl, de
+	ld [hl], "×"
+	inc hl
+	ld de, wItemQuantityChangeBuffer
+	lb bc, PRINTNUM_LEADINGZEROS | 1, 2
+	call PrintNum
+	ld a, [wMenuDataPointer]
+	ld e, a
+	ld a, [wMenuDataPointer + 1]
+	ld d, a
+	ld a, [wMenuDataBank]
+	call FarCall_de
+	ret
+; 25097
+
+ret_25097: ; 25097
+	ret
+; 25098
+
+DisplayPurchasePrice: ; 25098
+	call BuySell_MultiplyPrice
+	call BuySell_DisplaySubtotal
+	ret
+; 2509f
+
+DisplaySellingPrice: ; 2509f
+	call BuySell_MultiplyPrice
+	call Sell_HalvePrice
+	call BuySell_DisplaySubtotal
+	ret
+; 250a9
+
+BuySell_MultiplyPrice: ; 250a9
+	xor a
+	ld [hMultiplicand + 0], a
+	ld a, [wBuffer1]
+	ld [hMultiplicand + 1], a
+	ld a, [wBuffer2]
+	ld [hMultiplicand + 2], a
+	ld a, [wItemQuantityChangeBuffer]
+	ld [hMultiplier], a
+	push hl
+	call Multiply
+	pop hl
+	ret
+; 250c1
+
+Sell_HalvePrice: ; 250c1
+	push hl
+	ld hl, hProduct + 1
+	ld a, [hl]
+	srl a
+	ld [hli], a
+	ld a, [hl]
+	rra
+	ld [hli], a
+	ld a, [hl]
+	rra
+	ld [hl], a
+	pop hl
+	ret
+; 250d1
+
+BuySell_DisplaySubtotal: ; 250d1
+	push hl
+	ld hl, hMoneyTemp
+	ld a, [hProduct + 1]
+	ld [hli], a
+	ld a, [hProduct + 2]
+	ld [hli], a
+	ld a, [hProduct + 3]
+	ld [hl], a
+	pop hl
+	inc hl
+	ld de, hMoneyTemp
+	lb bc, PRINTNUM_MONEY | 3, 6
+	call PrintNum
+	call WaitBGMap
+	ret
+; 250ed
+
+TossItem_MenuHeader: ; 0x250ed
+	db MENU_BACKUP_TILES ; flags
+	menu_coords 15, 9, SCREEN_WIDTH - 1, TEXTBOX_Y - 1
+	dw ret_25097
+	db 0 ; default option
+; 0x250f5
+
+BuyItem_MenuHeader: ; 0x250f5
+	db MENU_BACKUP_TILES ; flags
+	menu_coords 7, 15, SCREEN_WIDTH - 1, SCREEN_HEIGHT - 1
+	dw DisplayPurchasePrice
+	db -1 ; default option
+; 0x250fd
+
+SellItem_MenuHeader: ; 0x250fd
+	db MENU_BACKUP_TILES ; flags
+	menu_coords 7, 15, SCREEN_WIDTH - 1, SCREEN_HEIGHT - 1
+	dw DisplaySellingPrice
+	db 0 ; default option
+; 0x25105

engine/items/printitemdescription.asm

@@ -0,0 +1,31 @@
+PrintItemDescription: ; 0x1c8955
+; Print the description for item [wCurSpecies] at de.
+
+	ld a, [wCurSpecies]
+	cp TM01
+	jr c, .not_a_tm
+
+	ld [wCurItem], a
+	push de
+	farcall GetTMHMItemMove
+	pop hl
+	ld a, [wd265]
+	ld [wCurSpecies], a
+	predef PrintMoveDesc
+	ret
+
+.not_a_tm
+	push de
+	ld hl, ItemDescriptions
+	ld a, [wCurSpecies]
+	dec a
+	ld c, a
+	ld b, 0
+	add hl, bc
+	add hl, bc
+	ld e, [hl]
+	inc hl
+	ld d, [hl]
+	pop hl
+	jp PlaceString
+; 0x1c8987

engine/items/switch_items.asm

@@ -0,0 +1,274 @@
+SwitchItemsInBag: ; 2490c (9:490c)
+	ld a, [wSwitchItem]
+	and a
+	jr z, .init
+	ld b, a
+	ld a, [wScrollingMenuCursorPosition]
+	inc a
+	cp b
+	jr z, .trivial
+	ld a, [wScrollingMenuCursorPosition]
+	call ItemSwitch_GetNthItem
+	ld a, [hl]
+	cp -1
+	ret z
+	ld a, [wSwitchItem]
+	dec a
+	ld [wSwitchItem], a
+	call Function249a7
+	jp c, Function249d1
+	ld a, [wScrollingMenuCursorPosition]
+	ld c, a
+	ld a, [wSwitchItem]
+	cp c
+	jr c, .asm_2497a
+	jr .asm_2494a
+
+.init
+	ld a, [wScrollingMenuCursorPosition]
+	inc a
+	ld [wSwitchItem], a
+	ret
+
+.trivial
+	xor a
+	ld [wSwitchItem], a
+	ret
+
+.asm_2494a
+	ld a, [wSwitchItem]
+	call Function24a40
+	ld a, [wScrollingMenuCursorPosition]
+	ld d, a
+	ld a, [wSwitchItem]
+	ld e, a
+	call Function24a6c
+	push bc
+	ld a, [wSwitchItem]
+	call ItemSwitch_GetNthItem
+	dec hl
+	push hl
+	call ItemSwitch_ConvertSpacingToDW
+	add hl, bc
+	ld d, h
+	ld e, l
+	pop hl
+	pop bc
+	call Function24aab
+	ld a, [wScrollingMenuCursorPosition]
+	call Function24a4d
+	xor a
+	ld [wSwitchItem], a
+	ret
+
+.asm_2497a
+	ld a, [wSwitchItem]
+	call Function24a40
+	ld a, [wScrollingMenuCursorPosition]
+	ld d, a
+	ld a, [wSwitchItem]
+	ld e, a
+	call Function24a6c
+	push bc
+	ld a, [wSwitchItem]
+	call ItemSwitch_GetNthItem
+	ld d, h
+	ld e, l
+	call ItemSwitch_ConvertSpacingToDW
+	add hl, bc
+	pop bc
+	call CopyBytes
+	ld a, [wScrollingMenuCursorPosition]
+	call Function24a4d
+	xor a
+	ld [wSwitchItem], a
+	ret
+
+Function249a7: ; 249a7 (9:49a7)
+	ld a, [wSwitchItem]
+	call ItemSwitch_GetNthItem
+	ld d, h
+	ld e, l
+	ld a, [wScrollingMenuCursorPosition]
+	call ItemSwitch_GetNthItem
+	ld a, [de]
+	cp [hl]
+	jr nz, .asm_249cd
+	ld a, [wScrollingMenuCursorPosition]
+	call Function24a97
+	cp 99
+	jr z, .asm_249cd
+	ld a, [wSwitchItem]
+	call Function24a97
+	cp 99
+	jr nz, .asm_249cf
+.asm_249cd
+	and a
+	ret
+
+.asm_249cf
+	scf
+	ret
+
+Function249d1: ; 249d1 (9:49d1)
+	ld a, [wSwitchItem]
+	call ItemSwitch_GetNthItem
+	inc hl
+	push hl
+	ld a, [wScrollingMenuCursorPosition]
+	call ItemSwitch_GetNthItem
+	inc hl
+	ld a, [hl]
+	pop hl
+	add [hl]
+	cp 100
+	jr c, .asm_24a01
+	sub 99
+	push af
+	ld a, [wScrollingMenuCursorPosition]
+	call ItemSwitch_GetNthItem
+	inc hl
+	ld [hl], 99
+	ld a, [wSwitchItem]
+	call ItemSwitch_GetNthItem
+	inc hl
+	pop af
+	ld [hl], a
+	xor a
+	ld [wSwitchItem], a
+	ret
+
+.asm_24a01
+	push af
+	ld a, [wScrollingMenuCursorPosition]
+	call ItemSwitch_GetNthItem
+	inc hl
+	pop af
+	ld [hl], a
+	ld hl, wMenuData_ItemsPointerAddr
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	ld a, [wSwitchItem]
+	cp [hl]
+	jr nz, .asm_24a25
+	dec [hl]
+	ld a, [wSwitchItem]
+	call ItemSwitch_GetNthItem
+	ld [hl], $ff
+	xor a
+	ld [wSwitchItem], a
+	ret
+
+.asm_24a25
+	dec [hl]
+	call ItemSwitch_ConvertSpacingToDW
+	push bc
+	ld a, [wSwitchItem]
+	call ItemSwitch_GetNthItem
+	pop bc
+	push hl
+	add hl, bc
+	pop de
+.asm_24a34
+	ld a, [hli]
+	ld [de], a
+	inc de
+	cp $ff
+	jr nz, .asm_24a34
+	xor a
+	ld [wSwitchItem], a
+	ret
+
+Function24a40: ; 24a40 (9:4a40)
+	call ItemSwitch_GetNthItem
+	ld de, wd002
+	call ItemSwitch_ConvertSpacingToDW
+	call CopyBytes
+	ret
+
+Function24a4d: ; 24a4d (9:4a4d)
+	call ItemSwitch_GetNthItem
+	ld d, h
+	ld e, l
+	ld hl, wd002
+	call ItemSwitch_ConvertSpacingToDW
+	call CopyBytes
+	ret
+
+ItemSwitch_GetNthItem: ; 24a5c (9:4a5c)
+	push af
+	call ItemSwitch_ConvertSpacingToDW
+	ld hl, wMenuData_ItemsPointerAddr
+	ld a, [hli]
+	ld h, [hl]
+	ld l, a
+	inc hl
+	pop af
+	call AddNTimes
+	ret
+
+Function24a6c: ; 24a6c (9:4a6c)
+	push hl
+	call ItemSwitch_ConvertSpacingToDW
+	ld a, d
+	sub e
+	jr nc, .dont_negate
+	dec a
+	cpl
+.dont_negate
+	ld hl, 0
+	call AddNTimes
+	ld b, h
+	ld c, l
+	pop hl
+	ret
+
+ItemSwitch_ConvertSpacingToDW: ; 24a80 (9:4a80)
+; This function is absolutely idiotic.
+	push hl
+	ld a, [wMenuData_ScrollingMenuSpacing]
+	ld c, a
+	ld b, 0
+	ld hl, .spacing_dws
+	add hl, bc
+	add hl, bc
+	ld c, [hl]
+	inc hl
+	ld b, [hl]
+	pop hl
+	ret
+
+; 24a91 (9:4a91)
+
+.spacing_dws ; 24a91
+	dw 0, 1, 2
+; 24a97
+
+Function24a97: ; 24a97 (9:4a97)
+	push af
+	call ItemSwitch_ConvertSpacingToDW
+	ld a, c
+	cp 2
+	jr nz, .not_2
+	pop af
+	call ItemSwitch_GetNthItem
+	inc hl
+	ld a, [hl]
+	ret
+
+.not_2
+	pop af
+	ld a, $1
+	ret
+
+Function24aab: ; 24aab (9:4aab)
+.loop
+	ld a, [hld]
+	ld [de], a
+	dec de
+	dec bc
+	ld a, b
+	or c
+	jr nz, .loop
+	ret

engine/items/tmhm.asm

@@ -0,0 +1,49 @@
+CanLearnTMHMMove: ; 11639
+	ld a, [wCurPartySpecies]
+	ld [wCurSpecies], a
+	call GetBaseData
+	ld hl, wBaseTMHM
+	push hl
+
+	ld a, [wPutativeTMHMMove]
+	ld b, a
+	ld c, 0
+	ld hl, TMHMMoves
+.loop
+	ld a, [hli]
+	and a
+	jr z, .end
+	cp b
+	jr z, .asm_11659
+	inc c
+	jr .loop
+
+.asm_11659
+	pop hl
+	ld b, CHECK_FLAG
+	push de
+	ld d, 0
+	predef SmallFarFlagAction
+	pop de
+	ret
+
+.end
+	pop hl
+	ld c, 0
+	ret
+; 1166a
+
+GetTMHMMove: ; 1166a
+	ld a, [wd265]
+	dec a
+	ld hl, TMHMMoves
+	ld b, 0
+	ld c, a
+	add hl, bc
+	ld a, [hl]
+	ld [wd265], a
+	ret
+; 1167a
+
+
+INCLUDE "data/moves/tmhm_moves.asm"

engine/items/updateitemdescription.asm

@@ -0,0 +1,13 @@
+UpdateItemDescription: ; 0x244c3
+	ld a, [wMenuSelection]
+	ld [wCurSpecies], a
+	hlcoord 0, 12
+	ld b, 4
+	ld c, SCREEN_WIDTH - 2
+	call TextBox
+	ld a, [wMenuSelection]
+	cp -1
+	ret z
+	decoord 1, 14
+	farcall PrintItemDescription
+	ret