;;; General ;;;
{
Gunship. Brings Samus to Zebes, acts as a save and recharge station, takes Samus from Zebes

Enemy ID:
    $D07F: Gunship top
    $D0BF: Gunship bottom / entrance pad
Bank: $A2
Enemy projectiles:
    $A379: Gunship liftoff dust clouds

; Gunship top
Parameter 0: Unused
Parameter 1: Unused
Parameter 2: Unused

; Gunship bottom
Parameter 0: Unused
Parameter 1: Unused
Parameter 2: Gunship part
{
    0: Gunship bottom
    1: Entrance pad
}

Uses palette 7 regardless of enemy set
Gunship top must be first enemy in room, followed by gunship bottom, then entrance pad
Gunship top must be first enemy in enemy set during escape, due to hardcoding the location of the liftoff dust clouds in VRAM ($A2:ABC7)

The initial Y position of gunship top enemy is moved 25px upwards, gunship bottom is moved 15px upwards
If landing on Zebes from Ceres or if a demo not in set 0 is playing, gunship top/bottom Y position is set to 17px above Samus
Entrance pad Y position is set to gunship top's Y position  1
If a demo in set 0 is playing, Samus' Y position is set to 472h

If landing on Zebes:
    Gunship moves itself and Samus down at a rate of 4.5 px/frame until Y position 300h;
    then 2.5 px/frame until gunship top Y position is 45Fh
    Note that Samus' initial position is set by Crateria load station 12h,
    once the ship lands it will teleport Samus to the enemy's X position (+ 1)

Spawns a palette FX object that modifies sprite palette 7 colour Fh
Uses load station 0 (hardcoded) for both post-landing save and manual save,
Crateria load station 0 has a hardcoded ship icon spawned over the usual save icon in the map (see $82:B6BC)
}


;;; Behaviour ;;;
{
Gunship bottom and entrance pad are primarily driven by the gunship top and only serve to run an instruction list for graphics with no main AI


}


;;; WRAM ;;;
{
; Gunship top
$0FA8: Function timer
$0FAC: Hover index. Cycles between 0..3. Indexes $A2:A7CF hover movement table. Initialised to 0.
$0FAE: Hover timer. Enemy processes next hover movement when this reaches zero. Initialised to 1. Reset value is 10h.
$0FB0: Brakes timer in braking (0..10h). Enemy fixed Y position, initialised to enemy Y position when ejecting Samus, used as reference point for Samus entering/exiting transitions.
$0FB2: Function. Initialised to $A80C if landing on Zebes, $AB60 if demo set 0 is playing, $A9BD otherwise.
{
    $A80C: Landing on Zebes - descending
    $A8D0: Landing on Zebes - apply brakes
    $A942: Landing on Zebes - wait for gunship entrance to open
    $A950: Landing on Zebes - eject Samus
    $A987: Landing on Zebes - wait for gunship entrance to close, then unlock Samus and save
    $A9BD: Idle - handle letting Samus enter
    $AA4F: Samus entering - wait for entrance pad to open
    $AA5D: Samus entering - lower Samus
    $AA94: Samus entering - wait for entrance pad to close
    $AAA2: Samus entered - go to liftoff or restore Samus health / ammo
    $AB1F: Samus entered - handle save confirmation
    $AB60: Samus exiting - wait for entrance pad to open
    $AB6E: Samus exiting - raise Samus
    $ABA5: Samus exiting - wait for entrance pad to close, then unlock Samus
    $ABC7: Liftoff - load dust cloud tiles
    $AC1B: Liftoff - fire up engines and spawn dust clouds
    $ACD7: Liftoff - steady rise
    $AD0E: Liftoff - accelerating / set game state
    $AD2D: Liftoff - accelerating
}

; Gunship bottom / entrance pad
$0FAE: Hover sound effect timer (if gunship bottom) (0..47h)
$0FB0: Liftoff timer (if gunship bottom) (0..80h)
$0FB2: Initialised to $A7D7 (RTL). Gunship Y velocity * 100h during liftoff (if gunship bottom)
}


;;; Enemy population ;;;
{
 ________________________________________ Enemy ID
|      __________________________________ X position
|     |     _____________________________ Y position
|     |    |      _______________________ Initialisation parameter
|     |    |     |      _________________ Properties. 2000h = process instructions, 400h = intangible
|     |    |     |     |     ____________ Extra properties
|     |    |     |     |    |      ______ Parameter 1
|     |    |     |     |    |     |     _ Parameter 2
|     |    |     |     |    |     |    |
; Room $91F8, state $9213. Landing site - default
; Room $91F8, state $922D. Landing site - event "Zebes is awake" is set
; Room $91F8, state $9247. Landing site - power bombs have been collected
D07F, 0480,0478, 0000, 2400,0000, 0000,0000 ; Gunship top
D0BF, 0480,0478, 0000, 2400,0000, 0000,0000 ; Gunship bottom / entrance pad
D0BF, 0480,0478, 0000, 2400,0000, 0000,0001 ; Gunship bottom / entrance pad

; Room $91F8, state $9261. Landing site - event "Zebes timebomb set" is set
D07F, 0480,0478, 0000, 2400,0000, 0000,0000 ; Gunship top
D0BF, 0480,0478, 0000, 2400,0000, 0000,0000 ; Gunship bottom / entrance pad
D0BF, 0480,0478, 0000, 2400,0000, 0000,0001 ; Gunship bottom / entrance pad
}


;;; Enemy header ;;;
{
 __________ Gunship top
|       ___ Gunship bottom / entrance pad
|      |
1000   0200    ; 0: Tile data size
A59E   A59E    ; 2: Palette
0014   0014    ; 4: Health
0028   0028    ; 6: Damage
005C   0060    ; 8: Width
0028   0028    ; Ah: Height
A2     A2      ; Ch: Bank
00     00      ; Dh: Hurt AI time
0000   0000    ; Eh: Cry
0000   0000    ; 10h: Boss ID
A644   A6D2    ; 12h: Initialisation AI
0001   0001    ; 14h: Number of parts
A759   804C    ; 18h: Main AI
800F   800F    ; 1Ah: Grapple AI
804C   804C    ; 1Ch: Hurt AI
8041   804C    ; 1Eh: Frozen AI
0000   0000    ; 20h: Time is frozen AI
0000   0000    ; 22h: Death animation
804C   804C    ; 28h: Power bomb reaction
0000   0000    ; 2Ah: Sidehopper variant index
804C   804C    ; 30h: Enemy touch
804C   804C    ; 32h: Enemy shot
ADB600 ADB600  ; 36h: Tile data
02     02      ; 39h: Layer
F3C2   F3C2    ; 3Ah: Drop chances ($B4)
EC1C   EC1C    ; 3Ch: Vulnerabilities ($B4)
0000   0000    ; 3Eh: Enemy name ($B4)
}


;;; Enemy vulnerabilities ;;;
{
; Default
}


;;; Enemy drop chances ;;;
{
00 ;        Small health
00 ;        Big health
00 ;        Missiles
FF ; 100.0% Nothing
00 ;        Super missiles
00 ;        Power bombs
}