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;;Edits By: Chdata/Fakescaper (Works in air)
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	RAM_AirMeter = $7F8827

	;; Where to place the meter relative to the screen boarder
	MeterPositionX = $E8
	MeterPositionY = $1E
	
	;; Possible values for the below variables:
	;;   (fast) $00, $01, $03, $07, $0f, $1f, $3f, $7f, $ff (slow)
	CountDownFrequency = $03
	CountUpFrequency = $00

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;; INIT and MAIN routines
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	DCB "INIT"
	LDA #$FF
	STA RAM_AirMeter
	RTL

        DCB "MAIN"
        PHB
        PHK
        PLB
        JSR MainSub
        PLB
        RTL
        
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;; Sprite Main
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MainSub:
	LDA RAM_AirMeter	; Play warning sounds

	CMP #$1C
	BEQ Sound
	CMP #$14
	BEQ Sound
	CMP #$0C
	BNE NoSound
Sound:	
	LDA #$2a
	STA $1DFC
NoSound:
	
	;; 	LDA RAM_AirMeter	; Change Mario's face blue
	;; 	CMP #$30
	;; 	BCS NoChangePal
	;; 	
	;;      LDY #$86              
	;;  	STY $2121             
	;; 	
	;; 	LDA #$31
	;; 	STA $2122
	;; 	LDA #$7e
	;; 	STA $2122	
	;; 	
	;; 	LDY #$8e              
	;;  	STY $2121             
	;; 	
	;; 	LDA #$ad
	;; 	STA $2122
	;; 	LDA #$6d
	;; 	STA $2122
	;; NoPalChange:
	
	LDA RAM_AirMeter	; If the meter is full...
	CMP #$FF		;  
	BNE Gfx			; ...and it has been for some time...
	LDA $1540,x		;
	BEQ NoGfx		; ...then skip the graphics routine
Gfx:	
	JSR SubGfx		; Draw the sprite
NoGfx:	

	LDA $9D			; Return if sprites are locked
	BNE Return0

LDA $1493			;If level end, do nothing to the meter
BNE SkipMeter

	LDA $75
	;BEQ CountUp
CountDown:
	LDA $13
	AND #CountDownFrequency
	BNE SkipMeter

	LDA RAM_AirMeter
	DEC A
	BNE SetMeter
	BRA KillMario
CountUp:
	LDA $13
	AND #CountUpFrequency
	BNE SkipMeter
	
	LDA RAM_AirMeter
	CMP #$FF
	BEQ SkipMeter

	LDA #$48
	STA $1540,x
	
	LDA RAM_AirMeter
	INC A
	;; 	LDA #$FF		; NOTE: Reinstate to make the meter instantly reset when not in water
SetMeter:	
	STA RAM_AirMeter
	
SkipMeter:		
	LDA $1a			; Position = Screen boundary
	CLC
	ADC #$80
	STA $E4,x		; This is done so the sprite stays on screen
	LDA $1b
	ADC #$00
	STA $14E0,x
	LDA $1c
	STA $D8,x
	LDA $1d
	STA $14D4,x
Return0:	
	RTS

KillMario:
	LDA #$90
	STA $7D
	LDA #$09		; Set death animation
	STA $71
	STA $1DFB		; Set death music
	LDA #$01
	STA $0DDA
	LDA #$30		; Set time until we return to the OW
	STA $1496
	STA $9D
	STZ $140D
	STZ $1407
	STZ $188A
	RTS


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; Graphics Routine
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	NumTiles = $05
	
SpriteTileDispX:    dcb $00,$08,$10,$18,$20,$27
SpriteTileDispY:    dcb $28,$20,$18,$10,$08,$01
SpriteGfxProp:	    dcb $80,$00,$00,$00,$00,$00

Palettes:           dcb $09,$05,$0B
	
SubGfx:
	JSR GetPalette
	;; 	LDA $15F6,x		; NOTE: Reinstate to use the palette from the cfg file
	STA $02
	
	LDA RAM_AirMeter	; Load address to be timed
	LSR
	LSR
	LSR
	STA $03
	
        LDY $15EA,x             ; get offset to sprite OAM                           

        PHX
        LDX #NumTiles
GfxLoopStart:

        LDA #MeterPositionX
        STA $0300,Y
	
	LDA #MeterPositionY
	CLC
	ADC SpriteTileDispY,x
        STA $0301,Y

	LDA $03
	JSR CalculateTile
        STA $0302,Y
	
        LDA $02
        ORA SpriteGfxProp,x
	ORA #$20
        STA $0303,Y
	
        INY    
        INY                     
        INY                     
        INY                     

	DEX
        BPL GfxLoopStart
	PLX

        LDY #$00
        LDA #NumTiles
        JSL $01B7B3
        RTS                       

GetPalette:
	LDY #$00
	LDA RAM_AirMeter
	CMP #$55
	BCC LoadPalette
	INY
	CMP #$AA
	BCC LoadPalette
	INY
LoadPalette:
	LDA Palettes,y
	RTS	
		
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;; 
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CalculateTile:
	CPX #$00
	BEQ EndPiece
	CPX #NumTiles
	BEQ EndPiece

	PHA
	TXA
	DEC A
	ASL
	ASL
	ASL
	STA $00
	PLA

	SEC
	SBC $00
	BMI EmptyTile
	
	CMP #$08 	
	BCS FullTile

	AND #$07
	CLC
	ADC #$47
	CMP #$4B
	BCC Return
	CLC
	ADC #$0C
Return:	
	RTS

FullTile:
	LDA #$46
	RTS
EmptyTile:
	LDA #$47
	RTS
EndPiece:
	LDA #$56
	RTS