SF2 Siel's Lifesteal hack

; =============== S U B R O U T I N E =======================================
; ASM FILE code\gameflow\battle\battleactions\battleactionsengine_4.asm
; 0xAAB6..0xAAFB
;There is 121 free bytes between 0x8000..0x10000 so the attack_new script could technically be placed here


WriteBattlesceneScript_Attack:

		jsr	WriteBattlesceneScript_Attack_New
		rts

; End of function WriteBattlesceneScript_Attack


; =============== S U B R O U T I N E =======================================
;NOTE: If using the standard patch: EXPANDED_ITEMS_AND_SPELLS
;Change $FFF6B0 to $FFF730

WriteBattlesceneScript_Attack_New:

                move.b  (a5),d0			;pointer to target
		jsr	GetCurrentHP
		move.w	d1,$FFF6B0		;store CurrentHP in RAM for later
		jsr	WriteBattlesceneScript_DetermineDodge
                tst.b   dodge(a2)
		bne.s   @DoubleAndCounter
		jsr	WriteBattlesceneScript_CalculateDamage
		jsr	WriteBattlesceneScript_DetermineCriticalHit
		jsr	WriteBattlesceneScript_InflictDamage
		tst.b   targetDies(a2)
		beq.s	@Continue
		jsr	WriteBattlesceneScript_DeathMessage
		bra.s	@CheckDodge

@Continue:
		jsr	WriteBattlesceneScript_InflictAilment
		tst.b	targetDies(a2)
		beq.s	@DoubleAndCounter
		exg     a4,a5
		jsr	WriteBattlesceneScript_DeathMessage
		exg     a4,a5
		bra.s	@CheckDodge

@DoubleAndCounter:

		jsr	WriteBattlesceneScript_DetermineDoubleAndCounter

@CheckDodge:
		tst.b	dodge(a2)
		bne.s	@Return
		bsr.s	Lifesteal_Effect
;		jsr	WriteBattlesceneScript_InflictCurseDamage   ;re-write, remove or set chance to 0% because bugs

@Return:
		clr.w	$FFF6B0
		rts

    ; End of function WriteBattlesceneScript_Attack_New

; =============== S U B R O U T I N E =======================================

Lifesteal_Effect:

		exg     a4,a5
		lsr.w	#1,d6			;leeches 1/2 of damage output.
		move.b (a5), d0
                jsr     GetEquippedWeapon
                cmpi.w  #ITEM_EVIL_KNUCKLES,d1
		beq.s	@TargetCurrentHPCap
                cmpi.w  #ITEM_EVIL_AXE,d1
		beq.s	@TargetCurrentHPCap
                cmpi.w  #ITEM_EVIL_SHOT,d1
		beq.s	@TargetCurrentHPCap
                cmpi.w  #ITEM_EVIL_LANCE,d1
		beq.s	@TargetCurrentHPCap
                cmpi.w  #ITEM_DARK_SWORD,d1
		beq.s	@TargetCurrentHPCap
                cmpi.w  #ITEM_DEMON_ROD,d1
		beq.s	@TargetCurrentHPCap
		bra.w	@Return

@TargetCurrentHPCap:

		move.b	(a4),d0			;pointer to target
		jsr	GetCurrentHP
		tst.w	d1			;checks if target dies
		bne.s	@MissingHPCap
		move.w	$FFF6B0,d6
		lsr.w	#1,d6			;leeches 1/2 of targets CurrentHP

@MissingHPCap:

		move.b	(a5),d0			;pointer to attacker
		jsr	GetMaxHP
		move.w	d1,d2
		jsr	GetCurrentHP
		sub.w	d1,d2
		cmp.w	d6,d2
		bcc.s	@AttackerAllyOrEnemy
		move.w	d2,d6			;cap recovery amount if missing HP is lower than leeched hp


@AttackerAllyOrEnemy:
		tst.w	d6			;check if leech amount equals 0
		beq.s	@Return			;rts if 0
		jsr	GetStatusEffects
		btst	#COMBATANT_BIT_ENEMY,d0
		bne.s	@EnemyAttacker
		executeAllyReaction d6,#0,d1,#2
		bra.s	@CheckDoubleAttack

@EnemyAttacker:
		executeEnemyReaction d6,#0,d1,#2
		bscHideTextBox

@CheckDoubleAttack:
		tst.b	doubleattack(a2)
		beq.s	@DisplayMessage
		move.w	d6,d1
		jsr	IncreaseCurrentHP	;second attack compensates the HP leeched on first hit (for missing hp recovery cap calculation)

@DisplayMessage:
                displayMessage #MESSAGE_BATTLE_RECOVERED_HIT_POINTS,d0,#0,d6
		exg     a4,a5

@Return:
		rts

		; End of function Lifesteal_Effect