path: root/engine/pokemon/evolve.asm

EvolvePokemon:
	ld hl, wEvolvableFlags
	xor a
	ld [hl], a
	ld a, [wCurPartyMon]
	ld c, a
	ld b, SET_FLAG
	call EvoFlagAction
EvolveAfterBattle:
	xor a
	ld [wMonTriedToEvolve], a
	dec a
	ld [wCurPartyMon], a
	push hl
	push bc
	push de
	ld hl, wPartyCount

	push hl

EvolveAfterBattle_MasterLoop:
	ld hl, wCurPartyMon
	inc [hl]

	pop hl

	inc hl
	ld a, [hl]
	cp $ff
	jp z, .ReturnToMap

	ld [wEvolutionOldSpecies], a

	push hl
	ld a, [wCurPartyMon]
	ld c, a
	ld hl, wEvolvableFlags
	ld b, CHECK_FLAG
	call EvoFlagAction
	ld a, c
	and a
	jp z, EvolveAfterBattle_MasterLoop

	ld a, [wEvolutionOldSpecies]
	dec a
	ld b, 0
	ld c, a
	ld hl, EvosAttacksPointers
	add hl, bc
	add hl, bc
	ld a, [hli]
	ld h, [hl]
	ld l, a

	push hl
	xor a
	ld [wMonType], a
	predef CopyMonToTempMon
	pop hl

.loop
	ld a, [hli]
	and a
	jr z, EvolveAfterBattle_MasterLoop

	ld b, a

	cp EVOLVE_TRADE
	jr z, .trade

	ld a, [wLinkMode]
	and a
	jp nz, .dont_evolve_2

	ld a, b
	cp EVOLVE_ITEM
	jp z, .item

	ld a, [wForceEvolution]
	and a
	jp nz, .dont_evolve_2

	ld a, b
	cp EVOLVE_LEVEL
	jp z, .level

	cp EVOLVE_HAPPINESS
	jr z, .happiness

; EVOLVE_STAT
	ld a, [wTempMonLevel]
	cp [hl]
	jp c, .dont_evolve_1

	call IsMonHoldingEverstone
	jp z, .dont_evolve_1

	push hl
	ld de, wTempMonAttack
	ld hl, wTempMonDefense
	ld c, 2
	call CompareBytes
	ld a, ATK_EQ_DEF
	jr z, .got_tyrogue_evo
	ld a, ATK_LT_DEF
	jr c, .got_tyrogue_evo
	ld a, ATK_GT_DEF
.got_tyrogue_evo
	pop hl

	inc hl
	cp [hl]
	jp nz, .dont_evolve_2

	inc hl
	jr .proceed

.happiness
	ld a, [wTempMonHappiness]
	cp HAPPINESS_TO_EVOLVE
	jp c, .dont_evolve_2

	call IsMonHoldingEverstone
	jp z, .dont_evolve_2

	ld a, [hli]
	cp TR_ANYTIME
	jr z, .proceed
	cp TR_MORNDAY
	jr z, .happiness_daylight

; TR_NITE
	ld a, [wTimeOfDay]
	cp NITE_F
	jp nz, .dont_evolve_3
	jr .proceed

.happiness_daylight
	ld a, [wTimeOfDay]
	cp NITE_F
	jp z, .dont_evolve_3
	jr .proceed

.trade
	ld a, [wLinkMode]
	and a
	jp z, .dont_evolve_2

	call IsMonHoldingEverstone
	jp z, .dont_evolve_2

	ld a, [hli]
	ld b, a
	inc a
	jr z, .proceed

	ld a, [wLinkMode]
	cp LINK_TIMECAPSULE
	jp z, .dont_evolve_3

	ld a, [wTempMonItem]
	cp b
	jp nz, .dont_evolve_3

	xor a
	ld [wTempMonItem], a
	jr .proceed

.item
	ld a, [hli]
	ld b, a
	ld a, [wCurItem]
	cp b
	jp nz, .dont_evolve_3

	ld a, [wForceEvolution]
	and a
	jp z, .dont_evolve_3
	ld a, [wLinkMode]
	and a
	jp nz, .dont_evolve_3
	jr .proceed

.level
	ld a, [hli]
	ld b, a
	ld a, [wTempMonLevel]
	cp b
	jp c, .dont_evolve_3
	call IsMonHoldingEverstone
	jp z, .dont_evolve_3

.proceed
	ld a, [wTempMonLevel]
	ld [wCurPartyLevel], a
	ld a, $1
	ld [wMonTriedToEvolve], a

	push hl

	ld a, [hl]
	ld [wEvolutionNewSpecies], a
	ld a, [wCurPartyMon]
	ld hl, wPartyMonNicknames
	call GetNick
	call CopyName1
	ld hl, EvolvingText
	call PrintText

	ld c, 50
	call DelayFrames

	xor a
	ldh [hBGMapMode], a
	hlcoord 0, 0
	lb bc, 12, 20
	call ClearBox

	ld a, $1
	ldh [hBGMapMode], a
	call ClearSprites
	call EvolutionAnimation

	push af
	call ClearSprites
	pop af
	jp c, CancelEvolution

	ld hl, CongratulationsYourPokemonText
	call PrintText

	pop hl

	ld a, [hl]
	ld [wCurSpecies], a
	ld [wTempMonSpecies], a
	ld [wEvolutionNewSpecies], a
	ld [wNamedObjectIndexBuffer], a
	call GetPokemonName

	push hl
	ld hl, EvolvedIntoText
	call PrintTextboxText
	push de

	ld de, MUSIC_NONE
	call PlayMusic
	ld de, SFX_CAUGHT_MON
	call PlaySFX
	call WaitSFX

	pop de
	ld c, 40
	call DelayFrames

	call ClearTilemap
	call UpdateSpeciesNameIfNotNicknamed
	call GetBaseData

	ld hl, wTempMonExp + 2
	ld de, wTempMonMaxHP
	ld b, TRUE
	predef CalcMonStats

	ld a, [wCurPartyMon]
	ld hl, wPartyMons
	ld bc, PARTYMON_STRUCT_LENGTH
	call AddNTimes
	ld e, l
	ld d, h
	ld bc, MON_MAXHP
	add hl, bc
	ld a, [hli]
	ld b, a
	ld c, [hl]
	ld hl, wTempMonMaxHP + 1
	ld a, [hld]
	sub c
	ld c, a
	ld a, [hl]
	sbc b
	ld b, a
	ld hl, wTempMonHP + 1
	ld a, [hl]
	add c
	ld [hld], a
	ld a, [hl]
	adc b
	ld [hl], a

	ld hl, wTempMonSpecies
	ld bc, PARTYMON_STRUCT_LENGTH
	call CopyBytes

	ld a, [wCurSpecies]
	ld [wTempSpecies], a
	xor a
	ld [wMonType], a
	call LearnLevelMoves
	ld a, [wTempSpecies]
	dec a
	call SetSeenAndCaughtMon

	ld a, [wTempSpecies]
	cp UNOWN
	jr nz, .skip_unown

	ld hl, wTempMonDVs
	predef GetUnownLetter
	callfar UpdateUnownDex

.skip_unown
	pop de
	pop hl
	ld a, [wTempMonSpecies]
	ld [hl], a
	push hl
	ld l, e
	ld h, d
	jp EvolveAfterBattle_MasterLoop

.dont_evolve_1
	inc hl
.dont_evolve_2
	inc hl
.dont_evolve_3
	inc hl
	jp .loop

; unused
	pop hl
.ReturnToMap:
	pop de
	pop bc
	pop hl
	ld a, [wLinkMode]
	and a
	ret nz
	ld a, [wBattleMode]
	and a
	ret nz
	ld a, [wMonTriedToEvolve]
	and a
	call nz, RestartMapMusic
	ret

UpdateSpeciesNameIfNotNicknamed:
	ld a, [wCurSpecies]
	push af
	ld a, [wBaseDexNo]
	ld [wNamedObjectIndexBuffer], a
	call GetPokemonName
	pop af
	ld [wCurSpecies], a
	ld hl, wStringBuffer1
	ld de, wStringBuffer2
.loop
	ld a, [de]
	inc de
	cp [hl]
	inc hl
	ret nz
	cp "@"
	jr nz, .loop

	ld a, [wCurPartyMon]
	ld bc, MON_NAME_LENGTH
	ld hl, wPartyMonNicknames
	call AddNTimes
	push hl
	ld a, [wCurSpecies]
	ld [wNamedObjectIndexBuffer], a
	call GetPokemonName
	ld hl, wStringBuffer1
	pop de
	ld bc, MON_NAME_LENGTH
	jp CopyBytes

CancelEvolution:
	ld hl, StoppedEvolvingText
	call PrintText
	call ClearTilemap
	pop hl
	jp EvolveAfterBattle_MasterLoop

IsMonHoldingEverstone:
	push hl
	ld a, [wCurPartyMon]
	ld hl, wPartyMon1Item
	ld bc, PARTYMON_STRUCT_LENGTH
	call AddNTimes
	ld a, [hl]
	cp EVERSTONE
	pop hl
	ret

CongratulationsYourPokemonText:
	text_far _CongratulationsYourPokemonText
	text_end

EvolvedIntoText:
	text_far _EvolvedIntoText
	text_end

StoppedEvolvingText:
	text_far _StoppedEvolvingText
	text_end

EvolvingText:
	text_far _EvolvingText
	text_end

LearnLevelMoves:
	ld a, [wTempSpecies]
	ld [wCurPartySpecies], a
	dec a
	ld b, 0
	ld c, a
	ld hl, EvosAttacksPointers
	add hl, bc
	add hl, bc
	ld a, [hli]
	ld h, [hl]
	ld l, a

.skip_evos
	ld a, [hli]
	and a
	jr nz, .skip_evos

.find_move
	ld a, [hli]
	and a
	jr z, .done

	ld b, a
	ld a, [wCurPartyLevel]
	cp b
	ld a, [hli]
	jr nz, .find_move

	push hl
	ld d, a
	ld hl, wPartyMon1Moves
	ld a, [wCurPartyMon]
	ld bc, PARTYMON_STRUCT_LENGTH
	call AddNTimes

	ld b, NUM_MOVES
.check_move
	ld a, [hli]
	cp d
	jr z, .has_move
	dec b
	jr nz, .check_move
	jr .learn
.has_move

	pop hl
	jr .find_move

.learn
	ld a, d
	ld [wPutativeTMHMMove], a
	ld [wNamedObjectIndexBuffer], a
	call GetMoveName
	call CopyName1
	predef LearnMove
	pop hl
	jr .find_move

.done
	ld a, [wCurPartySpecies]
	ld [wTempSpecies], a
	ret

FillMoves:
; Fill in moves at de for wCurPartySpecies at wCurPartyLevel

	push hl
	push de
	push bc
	ld hl, EvosAttacksPointers
	ld b, 0
	ld a, [wCurPartySpecies]
	dec a
	add a
	rl b
	ld c, a
	add hl, bc
	ld a, [hli]
	ld h, [hl]
	ld l, a
.GoToAttacks:
	ld a, [hli]
	and a
	jr nz, .GoToAttacks
	jr .GetLevel

.NextMove:
	pop de
.GetMove:
	inc hl
.GetLevel:
	ld a, [hli]
	and a
	jp z, .done
	ld b, a
	ld a, [wCurPartyLevel]
	cp b
	jp c, .done
	ld a, [wEvolutionOldSpecies]
	and a
	jr z, .CheckMove
	ld a, [wceed]
	cp b
	jr nc, .GetMove

.CheckMove:
	push de
	ld c, NUM_MOVES
.CheckRepeat:
	ld a, [de]
	inc de
	cp [hl]
	jr z, .NextMove
	dec c
	jr nz, .CheckRepeat
	pop de
	push de
	ld c, NUM_MOVES
.CheckSlot:
	ld a, [de]
	and a
	jr z, .LearnMove
	inc de
	dec c
	jr nz, .CheckSlot
	pop de
	push de
	push hl
	ld h, d
	ld l, e
	call ShiftMoves
	ld a, [wEvolutionOldSpecies]
	and a
	jr z, .ShiftedMove
	push de
	ld bc, wPartyMon1PP - (wPartyMon1Moves + NUM_MOVES - 1)
	add hl, bc
	ld d, h
	ld e, l
	call ShiftMoves
	pop de

.ShiftedMove:
	pop hl

.LearnMove:
	ld a, [hl]
	ld [de], a
	ld a, [wEvolutionOldSpecies]
	and a
	jr z, .NextMove
	push hl
	ld a, [hl]
	ld hl, MON_PP - MON_MOVES
	add hl, de
	push hl
	dec a
	ld hl, Moves + MOVE_PP
	ld bc, MOVE_LENGTH
	call AddNTimes
	ld a, BANK(Moves)
	call GetFarByte
	pop hl
	ld [hl], a
	pop hl
	jr .NextMove

.done
	pop bc
	pop de
	pop hl
	ret

ShiftMoves:
	ld c, NUM_MOVES - 1
.loop
	inc de
	ld a, [de]
	ld [hli], a
	dec c
	jr nz, .loop
	ret

EvoFlagAction:
	push de
	ld d, $0
	predef SmallFarFlagAction
	pop de
	ret

EvolutionAnimation:
	push hl
	push de
	push bc
	ld a, [wCurSpecies]
	push af
	ldh a, [rOBP0]
	push af
	ld a, %11100100
	ldh [rOBP0], a

	ld de, MUSIC_NONE
	call PlayMusic

	callfar ClearSpriteAnims

	ld de, .GFX
	ld hl, vTiles0
	lb bc, BANK(.GFX), 8
	call Request2bpp
	xor a
	ld [wLowHealthAlarm], a

	ld a, 1
	ldh [hBGMapMode], a

	call WaitBGMap
	xor a
	ldh [hBGMapMode], a

	ld a, [wEvolutionOldSpecies]
	ld [wPlayerHPPal], a
	ld c, 0
	call .GetSGBLayout

	ld a, [wEvolutionNewSpecies]
	ld [wCurPartySpecies], a
	ld [wCurSpecies], a
	call .PlaceFrontpic

	ld de, vTiles2
	ld hl, vTiles2 tile $31
	ld bc, 7 * 7
	call Request2bpp

	ld a, [wEvolutionOldSpecies]
	ld [wCurPartySpecies], a
	ld [wCurSpecies], a
	call .PlaceFrontpic

	ld a, 1
	ldh [hBGMapMode], a

	ld a, [wEvolutionOldSpecies]
	call PlayMonCry

	ld de, MUSIC_EVOLUTION
	call PlayMusic

	ld c, 80
	call DelayFrames

	ld c, 1
	call .GetSGBLayout

.AnimationSequence:
	call ClearJoypad
	lb bc, 1, 16 ; flash b times, wait c frames in between
.loop
	push bc
	call .WaitFrames_CheckPressedB
	jr c, .cancel
	call .Flash
	pop bc
	inc b
	dec c
	dec c
	jr nz, .loop

	xor a
	ld [wEvolutionCanceled], a

	ld a, 49
	ld [wEvolutionPicOffset], a
	call .ReplaceFrontpic

	ld a, [wEvolutionNewSpecies]
.return:
	ld [wPlayerHPPal], a

	ld c, 0
	call .GetSGBLayout
	call .PlayEvolvedSFX

	callfar ClearSpriteAnims

	ld a, [wPlayerHPPal]
	call PlayMonCry

	pop af
	ldh [rOBP0], a
	pop af
	ld [wCurSpecies], a
	pop bc
	pop de
	pop hl

	ld a, [wEvolutionCanceled]
	and a
	ret z

	scf
	ret

.cancel:
	pop bc
	ld a, 1
	ld [wEvolutionCanceled], a

	ld a, [wEvolutionOldSpecies]
	jr .return

.GetSGBLayout:
	ld b, SCGB_EVOLUTION
	jp GetSGBLayout

.PlaceFrontpic:
	call GetBaseData
	hlcoord 7, 2
	jp PrepMonFrontpic

.Flash:
	ld a, 7 * 7 ; previous stage
	ld [wEvolutionPicOffset], a
	call .ReplaceFrontpic
	ld a, -7 * 7 ; new stage
	ld [wEvolutionPicOffset], a
	call .ReplaceFrontpic
	dec b
	jr nz, .Flash
	ret

.ReplaceFrontpic:
	push bc
	xor a
	ldh [hBGMapMode], a
	hlcoord 7, 2
	lb bc, 7, 7
	ld de, SCREEN_WIDTH - 7
.loop1
	push bc
.loop2
	ld a, [wEvolutionPicOffset]
	add [hl]
	ld [hli], a
	dec c
	jr nz, .loop2
	pop bc
	add hl, de
	dec b
	jr nz, .loop1
	ld a, $1
	ldh [hBGMapMode], a
	call WaitBGMap
	pop bc
	ret

.WaitFrames_CheckPressedB:
	call DelayFrame
	push bc
	call JoyTextDelay
	ldh a, [hJoyDown]
	pop bc
	and B_BUTTON
	jr nz, .pressed_b
.loop3
	dec c
	jr nz, .WaitFrames_CheckPressedB
	and a
	ret

.pressed_b
	ld a, [wForceEvolution]
	and a
	jr nz, .loop3
	scf
	ret

.PlayEvolvedSFX:
	ld a, [wEvolutionCanceled]
	and a
	ret nz
	ld de, SFX_EVOLVED
	call PlaySFX
	ld hl, wJumptableIndex
	ld a, [hl]
	push af
	ld [hl], $0
.loop4
	call .balls_of_light
	jr nc, .done
	call .AnimateBallsOfLight
	jr .loop4

.done
	ld c, 32
.loop5
	call .AnimateBallsOfLight
	dec c
	jr nz, .loop5
	pop af
	ld [wJumptableIndex], a
	ret

.balls_of_light
	ld hl, wJumptableIndex
	ld a, [hl]
	cp 32
	ret nc
	ld d, a
	inc [hl]
	and $1
	jr nz, .done_balls
	ld e, $0
	call .GenerateBallOfLight
	ld e, $10
	call .GenerateBallOfLight

.done_balls
	scf
	ret

.GenerateBallOfLight:
	push de
	depixel 9, 11
	ld a, SPRITE_ANIM_INDEX_EVOLUTION_BALL_OF_LIGHT
	call InitSpriteAnimStruct
	ld hl, SPRITEANIMSTRUCT_JUMPTABLE_INDEX
	add hl, bc
	ld a, [wJumptableIndex]
	and %1110
	sla a
	pop de
	add e
	ld [hl], a
	ld hl, SPRITEANIMSTRUCT_TILE_ID
	add hl, bc
	ld [hl], $0
	ld hl, SPRITEANIMSTRUCT_0C
	add hl, bc
	ld [hl], $10
	ret

.AnimateBallsOfLight:
	push bc
	callfar PlaySpriteAnimations
	; a = (([hVBlankCounter] + 4) / 2) % NUM_PALETTES
	ldh a, [hVBlankCounter]
	and %1110
	srl a
	inc a
	inc a
	and $7
	ld b, a
	ld hl, wVirtualOAMSprite00Attributes
	ld c, NUM_SPRITE_OAM_STRUCTS
.loop6
	ld a, [hl]
	or b
	ld [hli], a ; attributes
rept SPRITEOAMSTRUCT_LENGTH - 1
	inc hl
endr
	dec c
	jr nz, .loop6
	pop bc
	call DelayFrame
	ret

.GFX:
INCBIN "gfx/evo/bubble_large.2bpp"
INCBIN "gfx/evo/bubble.2bpp"

GetPreEvolution:
; Find the first mon to evolve into wCurPartySpecies.

; Return carry and the new species in wCurPartySpecies
; if a pre-evolution is found.

	ld c, 0
.loop ; For each Pokemon...
	ld hl, EvosAttacksPointers
	ld b, 0
	add hl, bc
	add hl, bc
	ld a, [hli]
	ld h, [hl]
	ld l, a
.loop2 ; For each evolution...
	ld a, [hli]
	and a
	jr z, .no_evolve ; If we jump, this Pokemon does not evolve into wCurPartySpecies.
	cp EVOLVE_STAT ; This evolution type has the extra parameter of stat comparison.
	jr nz, .not_tyrogue
	inc hl

.not_tyrogue
	inc hl
	ld a, [wCurPartySpecies]
	cp [hl]
	jr z, .found_preevo
	inc hl
	ld a, [hl]
	and a
	jr nz, .loop2

.no_evolve
	inc c
	ld a, c
	cp NUM_POKEMON
	jr c, .loop
	and a
	ret

.found_preevo
	inc c
	ld a, c
	ld [wCurPartySpecies], a
	scf
	ret