jump    .nodeEntry920e33a5-99c2-429c-9214-3776f169051d
$cover.png DC8 "cover.png", 8
$quelle_destination.mp3 DC8 "quelle_destination.mp3", 8
$mediaChoice920e33a5-99c2-429c-9214-3776f169051d DC32, 2, .nodeEntryea561fb0-994b-4777-80f3-58860eda97d6, .nodeEntry45fb3875-38aa-4683-abba-06868c8e109c

$saturne.png DC8 "saturne.png", 8
$saturne.mp3 DC8 "saturne.mp3", 8
$mediaChoice45fb3875-38aa-4683-abba-06868c8e109c DC32, 1, .nodeEntry42abccda-d683-409d-aed9-7727df3d6974

$mars.png DC8 "mars.png", 8
$mars.mp3 DC8 "mars.mp3", 8
$mediaChoiceea561fb0-994b-4777-80f3-58860eda97d6 DC32, 1, .nodeEntryca6a2e13-f4f0-4d1e-a64c-11acacfb97c0

$sature_story.mp3 DC8 "sature_story.mp3", 8
$mediaChoice42abccda-d683-409d-aed9-7727df3d6974 DC32, 0, 
$mars_story.mp3 DC8 "mars_story.mp3", 8
$mediaChoiceca6a2e13-f4f0-4d1e-a64c-11acacfb97c0 DC32, 0, 
; ---------------------------- Default node Type: Choice
.nodeEntry920e33a5-99c2-429c-9214-3776f169051d:
lcons r0, $cover.png
lcons r1, $quelle_destination.mp3
syscall 1
lcons r0, 0b10000000000
syscall 2
lcons r0, $mediaChoice920e33a5-99c2-429c-9214-3776f169051d
jump .media ; no return possible, so a jump is enough
; ---------------------------- Default node Type: Transition
.nodeEntry45fb3875-38aa-4683-abba-06868c8e109c:
lcons r0, $saturne.png
lcons r1, $saturne.mp3
syscall 1
lcons r0, .nodeEntry42abccda-d683-409d-aed9-7727df3d6974
ret

; ---------------------------- Default node Type: Transition
.nodeEntryea561fb0-994b-4777-80f3-58860eda97d6:
lcons r0, $mars.png
lcons r1, $mars.mp3
syscall 1
lcons r0, .nodeEntryca6a2e13-f4f0-4d1e-a64c-11acacfb97c0
ret

; ---------------------------- Default node Type: End
.nodeEntry42abccda-d683-409d-aed9-7727df3d6974:
lcons r0, 0
lcons r1, $sature_story.mp3
syscall 1
ret

; ---------------------------- Default node Type: End
.nodeEntryca6a2e13-f4f0-4d1e-a64c-11acacfb97c0:
lcons r0, 0
lcons r1, $mars_story.mp3
syscall 1
ret

; Generic media choice manager
.media:
    ; Les adresses des différents medias sont dans la stack
; Arguments:
    ; r0: address d'une structure de type "media choice"
; Local:
    ; t0: current media address
    ; t1: increment 4
    ; t3: address of the first element in the choice array
    ; t4: address of the last element in the choice array
    ; t5: where to jump when OK button is pressed
    
    mov t3, r0  ; copie de R0 pour travailler dessus
    mov t2, r0  ; sauvegarde de R0
    load r0, @t3, 4 ; Le premier élément est le nombre de choix possibles, ex: r0 = 12
    lcons t1, 4
    mul r0, t1  ; on calcule l'offset: r0 = nb_elements * 4 = 48
    mov t4, t3  ; t4 = t3
    add t4, r0  ; t4 pointe maintenant sur le dernier élément de la structure
    add t3, t1  ; t3 pointe maintenant sur le premier élément
    mov t0, t3      ; on commence sur le premier élément
    
.media_loop:

    ; --------- We call a media transition node
    load r0, @t0, 4 ; Get the address located at memory T0
    call r0 ; call subroutine   
    ; Return argument in R0: the address of the node to call whe OK is pressed
    mov t5, r0  ; save it
    
    ; wait for event
    lcons r0, 0b100111 ; mask for OK, previous and next buttons, home button
    syscall 2
    ; Event is stored in R0

    ; -----  Test if event is OK button
    lcons r1, 1 ; mask for OK button
    and r1, r0 ; r1 = r1 AND r0
    skipz r1 ; not OK, skip jump
    jump .media_wait_event
    
    ; test previous event
    lcons r1, 2 ; mask for previous button
    and r1, r0 ; r1 = r1 AND r0
    skipz r1 ; not OK, skip jump
    jump .media_previous

    lcons r1, 0b100000 ; mask for home button
    and r1, r0 ; r1 = r1 AND r0
    skipz r1 ; not Home, skip jump
    jump .media_exit

    ; all other events mean: next node
    eq  r0, t0, t4   ;  t4 est le dernier élément
    skipz r0   ;  zéro, on peut incrémenter l'adresse
    jump .media_set_first
    add  t0, t1 ; t0 += 4
    jump .media_loop
 
 .media_set_first:  ; on reboucle sur le premier élément de la structure
    mov t0, t3
    jump .media_loop

.media_previous:
    eq r0, t0, t3   ; on teste si on est au premier élément
    skipz r0   ;  zéro, on peut décrémenter l'adresse
    jump .media_set_last
    sub  t0, t1 ; t0 += 4
    jump .media_loop
 
 .media_set_last:  ; on reboucle sur le dernier élément de la structure
    mov t0, t4
    jump .media_loop

.media_wait_event:
    call t5 ; jump to the node
    lcons r0, 0b10000100001 ; mask for end of audio, Ok, and home buttons
    syscall 2 ; wait for event (OK, home or end of audio), return to choice loop
    jump .media_loop

.media_exit:
    lcons r0, 1 ; Home button pressed, send signal to exit story
    syscall 3 ; exit story, we should never return from this call
    halt ; just in case