ref: 21c266b950e5f4379bb7c3f605689b9070c8f48d
dir: /engine/battle/move_effects/substitute.asm/
SubstituteEffect_:
ld c, 50
call DelayFrames
ld hl, wBattleMonMaxHP
ld de, wPlayerSubstituteHP
ld bc, wPlayerBattleStatus2
ldh a, [hWhoseTurn]
and a
jr z, .notEnemy
ld hl, wEnemyMonMaxHP
ld de, wEnemySubstituteHP
ld bc, wEnemyBattleStatus2
.notEnemy
ld a, [bc]
bit HAS_SUBSTITUTE_UP, a ; user already has substitute?
jr nz, .alreadyHasSubstitute
; quarter health to remove from user
; assumes max HP is 1023 or lower
push bc
ld a, [hli]
ld b, [hl]
srl a
rr b
srl a
rr b ; max hp / 4
push de
ld de, wBattleMonHP - wBattleMonMaxHP
add hl, de ; point hl to current HP low byte
pop de
ld a, b
ld [de], a ; save copy of HP to subtract in wPlayerSubstituteHP/wEnemySubstituteHP
ld a, [hld]
; subtract [max hp / 4] to current HP
sub b
ld d, a
ld a, [hl]
sbc 0
pop bc
jr c, .notEnoughHP ; underflow means user would be left with negative health
; bug: since it only branches on carry, it will possibly leave user with 0 HP
.userHasZeroOrMoreHP
ldi [hl], a ; save resulting HP after subtraction into current HP
ld [hl], d
ld h, b
ld l, c
set HAS_SUBSTITUTE_UP, [hl]
ld a, [wOptions]
bit 7, a ; battle animation is enabled?
ld hl, PlayCurrentMoveAnimation
ld b, BANK(PlayCurrentMoveAnimation)
jr z, .animationEnabled
ld hl, AnimationSubstitute
ld b, BANK(AnimationSubstitute)
.animationEnabled
call Bankswitch ; jump to routine depending on animation setting
ld hl, SubstituteText
call PrintText
jpfar DrawHUDsAndHPBars
.alreadyHasSubstitute
ld hl, HasSubstituteText
jr .printText
.notEnoughHP
ld hl, TooWeakSubstituteText
.printText
jp PrintText
SubstituteText:
text_far _SubstituteText
text_end
HasSubstituteText:
text_far _HasSubstituteText
text_end
TooWeakSubstituteText:
text_far _TooWeakSubstituteText
text_end