;license:MIT
;(c) 2018-2021 by 4am & qkumba
;
; HGR title and action slideshows
;
; Public functions
; - HGRTitleSlideshow
; - HGRActionSlideshow
; - HGRSingle
;

;------------------------------------------------------------------------------
; HGRTitleSlideshow
; execute a slideshow of hi-res title screenshots
;
; in:    none
; out:   everything clobbered
;        graphics mode still displaying hi-res screen with last picture visible
;------------------------------------------------------------------------------
HGRTitleSlideshow
         jsr   LoadHGRTransition     ; load transition effect code at $6000
         jsr   okvs_iter             ; cycle through all listed HGR files
         !word gSlideshowStore
         !word HGRTitleCallback      ; address of callback (called on each file)
         rts                         ; exit with last picture still visible

;------------------------------------------------------------------------------
; HGRActionSlideshow
; execute a slideshow of hi-res action screenshots
;
; in:    none
; out:   everything clobbered
;        graphics mode still displaying hi-res screen with last picture visible
;------------------------------------------------------------------------------
HGRActionSlideshow
         jsr   LoadHGRTransition     ; load transition effect code at $6000
         jsr   okvs_iter             ; cycle through all listed HGR files
         !word gSlideshowStore
         !word HGRActionCallback     ; address of callback (called on each file)
         rts                         ; exit with last picture still visible

;------------------------------------------------------------------------------
; HGRSingle
; display a single hi-res screenshot, with transition effect
;
; in:    none
; out:   everything clobbered
;        graphics mode still displaying hi-res screen with last picture visible
;------------------------------------------------------------------------------
HGRSingle
         +ST16 IndexedHGRFilename
         jsr   LoadIndexedHGRFile
         jsr   DecompressHGR
         jsr   LoadHGRTransition     ; load transition effect code at $6000
         jmp   ExecuteTransitionAt6000AndWait

;------------------------------------------------------------------------------
; LoadHGRTransition [private]
; looks up name of next HGR transition effect in FX.CONF and loads that file
; at $6000

; in:    gGlobalPrefsStore has been initialized
; out:   all registers and flags clobbered
;        $6000..$BFFF contains transition effect code
;------------------------------------------------------------------------------
LoadHGRTransition
         jsr   LoadIndexedFile       ; load HGR transition effects list into $6000
-        !word $6000
         !word kFXIndexRecord

         jsr   pref_get              ; get HGR transition effect from prefs
         !word kNextFX
         !word -
         +ST16 @indexRecordPtr       ; A/Y = filename (don't load file yet)
                                     ; $WINDEX = index of the transition in FX store
         +LDADDR -
         jsr   okvs_next             ; get transition after this one
         +ST16 +

         jsr   pref_set              ; update prefs store and save to disk
         !word kNextFX
+        !word $FDFD                 ; SMC

         jsr   LoadIndexedFile
         !word $6000
@indexRecordPtr
         !word $FDFD                 ; SMC
HGRRTS   rts

;------------------------------------------------------------------------------
; HGRTitleCallback [private]
; callback called by okvs_iter on gSlideshowStore
; to load and display a single HGR title screenshot

; in:    A/Y contains address of filename (name only, path is always /TITLE.HGR/)
;        $WINDEX contains 0-based index of the current record in gSlideshowStore (word)
; out:   all registers and flags clobbered
;        $0800..$1EFF preserved (this contains the gSlideshowStore OKVS data)
;        $2000..$BFFF clobbered by graphics data and transition code
;------------------------------------------------------------------------------
HGRTitleCallback
         bit   KBD
         bmi   HGRRTS

         +ST16 @fname
         +ST16 gLastMegaAttractGame

         jsr   FindGame
         ; if game is not found (C will be set here), it means it can't be played on
         ; this machine due to memory or joystick requirements, so we don't display
         ; it in slideshows
         bcs   HGRRTS

         +LD16 WINDEX                ; save game index in case user hits RETURN
         +ST16 gGameToLaunch         ; while it's visible (we'll launch it)

         jsr   LoadIndexedFile       ; load index file into $4000
-        !word $4000
         !word kHGRTitleIndexRecord

         jsr   okvs_find
         !word -
@fname   !word $FDFD                 ; SMC
         +ST16 @indexRecordPtr

         lda   #$00
         sta   $5FFD

         jsr   LoadIndexedFile       ; load HGR graphic at $4000
         !word $4000
@indexRecordPtr
         !word $FDFD                 ; SMC

         lda   $5FFD
         cmp   #$4C                  ; Check if screen hole now contains a JMP
         beq   @noUnpack             ; if so, file was not packed, so skip unpack
         jsr   UnpackHGRTitle
@noUnpack
         jmp   ExecuteTransitionAt6000AndWait

;------------------------------------------------------------------------------
; HGRActionCallback [private]
; callback called by okvs_iter on gSlideshowStore
; to load and display a single HGR action screenshot

; in:    A/Y contains address of filename (name only, path is always /ACTION.HGR/)
;        $WINDEX contains 0-based index of the current record in gSlideshowStore (word)
; out:   all registers and flags clobbered
;        $0800..$1EFF preserved (this contains the gSlideshowStore OKVS data)
;        $2000..$BFFF clobbered by graphics data and transition code
;------------------------------------------------------------------------------
HGRActionCallback
         bit   KBD
         bmi   HGRRTS

         +ST16 IndexedHGRFilename

         jsr   FindGame
         ; if game name is not found (C will be set here), it means the game
         ; can't be played due to memory or joystick requirements, so we hide
         ; it from slideshows
         bcs   HGRRTS

         jsr   LoadIndexedHGRFile
         jsr   DecompressHGR
         jmp   DrawGameTitleInActionSlideshow

LoadIndexedHGRFile
; in:    caller has set IndexedHGRFilename
; out:   all flags & registers clobbered
         +LD16 IndexedHGRFilename
         +ST16 PTR
         ldy   #1
         lda   (PTR), y
         sec
         sbc   #$41                  ; A in [0..25]
         lsr                         ; A in [0..15]
         lsr                         ; A in [0..7]
         tax
         lda   kHGRActionIndexLo, x
         sta   HGRActionIndexRecord
         lda   kHGRActionIndexHi, x
         sta   HGRActionIndexRecord+1

         jsr   LoadIndexedFile       ; load index file into $4000
HGRActionIndexPtr
         !word $4000
HGRActionIndexRecord
         !word $FDFD                 ; SMC

         jsr   okvs_find
         !word HGRActionIndexPtr
IndexedHGRFilename
         !word $FDFD                 ; SMC
         +ST16 @indexRecordPtr

         jsr   LoadIndexedFile       ; load compressed HGR screenshot at $3FF8
         !word $3FF8
@indexRecordPtr
         !word $FDFD                 ; SMC
         rts