;Hook code

 include "settings.inc"
 include "ti83plus.inc"
 include "equates.inc" 
 SEGMENT Main
 GLOBALS ON

 EXTERN PutSApp,IGetKey,DispHexA,DispHexArray,loadAppVar,IPutS,DispHexHL,translatePage,VPutSApp,DoLog
 EXTERN varNameBackup

lockdownLinkHook:
       add a,e
       ld hl,silentLinkHandler
       call APP_PUSH_ERRORH
doLockdown:
;       B_CALL GetSmallPacket
       ld e,0
       in a,(0)
       set 0,(iy+3Eh)
       B_CALL RejectCommand
       jr exitSilentLinkHook

;(appData):
;0 = Respond normally
;1 = Ignore all communication
;2 = Reject all communication
;3 = Stealth mode
;4 = When activity, run program
;5 = Alternate remote program
;appData+1:
; zero-terminated program name

silentLinkHook:
       add a,e
       ld hl,silentLinkHandler
       call APP_PUSH_ERRORH
;       call loadAppVar
;       ld hl,appData+1
;       rst 20h
;       ld a,(appData)
;       dec a
;       jr z,exitSilentLinkHook
;       dec a
;       jr z,doLockdown
;       dec a
;       dec a
;       jr z,executeProgram
       xor a
       ld (appData),a
       ld (iy+linkFlags),0
       B_CALL ContinueGetByte
       B_CALL Get3Bytes
       ld a,(header+1)
       ld hl,linkHandlerTable
       ld b,NUMBER_OF_PACKETS
$$:    cp (hl)
       jr z,$F
       inc hl
       inc hl
       djnz $B
exitSilentLinkHook:
       call APP_POP_ERRORH
silentLinkHandler:
       res indicOnly,(iy+indicFlags)
       xor a
       ret
$$:    B_CALL ldhlind
       jp (hl)
readyPacket:
;       ld b,68h
;       call DoLog
       B_CALL SendAck
       jr exitSilentLinkHook
enableKeyEcho:
       ld a,(appData)
       cp 3
       jr z,$F
       set 5,(iy+33h)
$$:    B_CALL SendAck
       jr exitSilentLinkHook
disableKeyEcho:
       ld a,(appData)
       cp 3
       jr z,$F
       res 5,(iy+33h)
$$:    B_CALL SendAck
       jr exitSilentLinkHook
enableLockdown:
       ld a,(appData)
       cp 3
       jr z,$F
       ld hl,lockdownLinkHook
       in a,(6)
       B_CALL EnableLinkActivityHook
$$:    B_CALL SendAck
       jr exitSilentLinkHook
disableLockdown:
       ld a,(appData)
       cp 3
       jr z,$F
       res 4,(iy+33h)
$$:    B_CALL SendAck
       jr exitSilentLinkHook
getDeviceInfo:
       call sendDeviceInfo
       jr exitSilentLinkHook
remoteControl:
       B_CALL SendAck
       B_CALL SendAck
       call APP_POP_ERRORH
       ld a,(appData)
       cp 3
       jr z,exitSilentLinkHook
       ld a,(header+3)
       ld (keyExtend),a
       ld a,(header+2)
       B_JUMP JForceCmd
getScreenContents:
       ld a,(appData)
       cp 3
       jr z,$F
       B_CALL SendScreenContents
       jr exitSilentLinkHook
$$:    ld hl,ioData
       ld (hl),00h
       inc hl
       ld (hl),03h
       inc hl
       ld (hl),12h
       ld hl,ioData
       ld de,3
       ld a,06h
       ld (sndRecState),a ;needs to not be 08h
       B_CALL SendRAMCmd
       B_CALL Get4BytesNC
       B_CALL SendAck
       ld hl,savesscreen
       ld bc,768
       B_CALL MemClear
       ld hl,savesscreen
       ld de,768
       ld a,15h
       B_CALL SendRAMCmd
       jr exitSilentLinkHook
receiveVarAndRun:
       set executeAfter,(iy+linkmanFlags)
       jr $F
receiveVar:
receiveVarNormal:
receiveRAMVar:
       res executeAfter,(iy+linkmanFlags)
$$:    B_CALL GetSmallPacket
       ld a,(appData)
       cp 3
       jr z,receiveVarStealth
       ld hl,ioData+2
       ld de,varNameBackup
       ld bc,9
       ldir
       xor a
       ld (de),a
       ld a,15h
       ld (sndRecState),a
       B_CALL ReceiveVar
       bit executeAfter,(iy+linkmanFlags)
       jr z,exitSilentLinkHook
       B_CALL CloseEditEqu
       ld hl,varNameBackup
       rst 20h
       ld hl,$F
       call APP_PUSH_ERRORH
       B_CALL ParseInp
       call APP_POP_ERRORH
       call APP_POP_ERRORH
       B_JUMP JForceCmdNoChar
$$:    B_CALL ExecutePrgm
       call APP_POP_ERRORH
       B_JUMP JForceCmdNoChar
receiveVarStealth:
       ld h,09h
       B_CALL Send4BytePacket
       ld de,0000h
       xor a
       ld (arcInfo),a
       B_CALL GetDataPacket
       B_CALL Get4BytesNC
       ld a,(header+1)
       cp 92h
       jr nz,receiveVar
       B_CALL SendAck
       jr exitSilentLinkHook
sendVar:
       B_CALL GetSmallPacket
       B_CALL ZeroOP1
       ld hl,ioData+2
       rst 20h
       ld a,0Ah
       ld (sndRecState),a
       B_CALL SendVariable
       ld h,92h
       B_CALL Send4BytePacket
       jr exitSilentLinkHook
getCalcID:
       B_CALL SendAck
       B_CALL GetCalcSerial
       ld hl,ioData
       ld bc,9
       B_CALL MemClear
       ld hl,OP4
       ld de,ioData
       ld bc,5
       ldir
       ld a,15h
       ld hl,ioData
       ld de,9
       B_CALL SendRAMCmd
       jr exitSilentLinkHook
testguard2Packet:
       B_CALL GetSmallPacket
       ld h,09h
       B_CALL Send4BytePacket
       B_CALL Get4BytesNC
       ld a,(header+1)
       cp 92h
       jr nz,testguard2Packet
       B_CALL SendAck
       call APP_POP_ERRORH
       ld hl,(curRow)
       push hl
       call displayResetAndPause
       ld hl,0
       ld (curRow),hl
       ld hl,textShadow
       ld b,128
$$:    ld a,(hl)
       inc hl
       B_CALL PutC
       djnz $B
       pop hl
       ld (curRow),hl
       B_JUMP JForceCmdNoChar
displayResetAndPause:
       B_CALL ClrLCDFull
       B_CALL CursorOff
       ld hl,sTransferComplete
       B_CALL SStringLength
       ld a,96
       sub b
       srl a
       ld (penCol),a
       ld a,8
       ld (penRow),a
       ld hl,sTransferComplete+1
       call VPutSApp
       ld hl,2800h
       ld (penCol),hl
       ld hl,sConfirmationCode
       call VPutSApp
       ld hl,0C05h
       ld (curRow),hl
       ld hl,ioData
       res appTextSave,(iy+appFlags)
       call PutSApp
       B_CALL RunIndicOff
       res indicOnly,(iy+indicFlags)
       B_CALL GetKeyRetOff
       ret
unknown47h:
       ld hl,86B7h
       ld (iMathPtr5),hl
       ld hl,(header+2)
       ld de,32
       B_CALL cphlde
       jr nz,throwError
       B_CALL GetVariableData
       jr exitSilentLinkHook
unknown74h:
       ld a,47h
       ld hl,86B7h
       ld de,32
       B_CALL SendRAMCmd
       jr exitSilentLinkHook
deleteVar:
       B_CALL GetSmallPacket
       ld a,(appData)
       cp 3
       jr z,varDeleted
       ld hl,ioData+2
       rst 20h
       ld a,(OP1)
       cp 14h
       jr z,$F
       B_CALL ChkFindSym
       jr c,exitSilentLinkHook
       B_CALL DelVarArc
       B_CALL SendAck
       jr exitSilentLinkHook
$$:    B_CALL FindApp
       jr c,exitSilentLinkHook
       B_CALL DeleteApp
varDeleted:
       B_CALL SendAck
       jr exitSilentLinkHook
memoryDump:
       B_CALL GetSmallPacket
       ld bc,(ioData)
       ld a,b
       or a
       jr nz,throwError
       ld hl,(pagedCount)
       push hl
       ld hl,(pagedGetPtr)
       push hl
       ld hl,(pagedPutPtr)
       push hl
       ld hl,dumpErrorHandler
       call APP_PUSH_ERRORH
       ld bc,(ioData)
       ld b,c
       ld de,(ioData+2)
       B_CALL SetupPagedPtr
       ld de,(ioData+4)
       ld (header+2),de
       ld a,15h
       ld (header+1),a
       B_CALL Send4Bytes
       ld de,0
       ld (header+4),de
       ld de,(header+2)
$$:    push de
       ld c,(hl)
       B_CALL PagedGet
       ld c,a
       B_CALL SendDataByte
       pop de
       dec de
       ld a,d
       or e
       jr nz,$B
       call APP_POP_ERRORH
       pop de
       pop de
       pop bc
       B_CALL SetupPagedPtr
       ei
       ld a,(header+4)
       B_CALL SendAByte
       ld a,(header+5)
       B_CALL SendAByte
       B_CALL Get4BytesNC
       jr exitSilentLinkHook
dumpErrorHandler:
       pop de
       pop de
       pop bc
       B_CALL SetupPagedPtr
       jr throwError
remoteExecution:
       B_CALL GetSmallPacket
       B_CALL SendAck
       ld a,(appData)
       cp 3
       jr z,exitSilentLinkHook
       ld hl,ioData+2
       rst 20h
       ld a,(OP1)
       cp 14h
       jr z,isFlashApplication
       ld a,(appData)
       cp 5
       jr nz,$F
       ld hl,appData+1
       rst 20h
       jr $F
executeProgram:
       call APP_POP_ERRORH
$$:    ld hl,$F
       call APP_PUSH_ERRORH
       set 1,(iy+08h)
       B_CALL ParseInp
       call APP_POP_ERRORH
       B_JUMP JForceCmdNoChar
$$:    B_CALL ExecutePrgm
       B_JUMP JForceCmdNoChar
isFlashApplication:
       ld hl,OP1+1
       ld de,progToEdit
       ld bc,8
       ldir
       B_CALL ExecuteApp
       B_JUMP JForceCmdNoChar ;some apps are dumb and need this
throwError:
       B_JUMP ErrLinkXmit
sendDeviceInfo:
       B_CALL SendAck
       B_CALL Get4BytesNC
       cp 09h
       jr nz,throwError
       B_CALL SendAck
       B_CALL GetBaseVer
       ld hl,ioData
       ld (hl),a
       inc hl
       ld (hl),b
       inc hl
       B_CALL GetBootVer
       ld (hl),a
       inc hl
       ld (hl),b
       inc hl
       push hl
       B_CALL Chk_Batt_Low
       ld a,2
       jr nz,$F
       ld a,3
$$:    pop hl
       inc hl
       ld (hl),a
       ld (sndRecState),a ;needs to not be 08h
       B_CALL GetHWVer
       inc hl
       ld (hl),a
       ld de,(localLanguage)
       inc hl
       ld (hl),e
       inc hl
       ld (hl),d
       inc hl
       ld (hl),0
       inc hl
       ld (hl),0
       inc hl
       ld (hl),0
       ld a,15h
       ld hl,ioData
       ld de,11
       B_CALL SendRAMCmd
       ret
linkHandlerTable:
       DB 68h
       DW readyPacket
       DB 2Bh
       DW enableKeyEcho
       DB 2Ch
       DW disableKeyEcho
       DB 29h
       DW enableLockdown
       DB 2Ah
       DW disableLockdown
       DB 2Dh
       DW getDeviceInfo
       DB 70h
       DW testguard2Packet
       DB 47h
       DW unknown47h
       DB 74h
       DW unknown74h
       DB 87h
       DW remoteControl
       DB 6Eh
       DW getCalcID
       DB 6Fh
       DW memoryDump
       DB 6Dh
       DW getScreenContents
       DB 0C9h
       DW receiveVar
       DB 0CAh
       DW receiveVarAndRun
       DB 0A2h
       DW sendVar
       DB 88h
       DW deleteVar
       DB 89h
       DW remoteExecution
       DB 0B7h
       DW receiveRAMVar
       DB 06h
       DW receiveVarNormal
linkHandlerTableEnd:

NUMBER_OF_PACKETS EQU (linkHandlerTableEnd-linkHandlerTable)/3

sTransferComplete:
       DB 17h,"TRANSFER",06h,"COMPLETE",0
sConfirmationCode:
       DB "CONFIRMATION",06h,"CODE:",0
       COMMENT ~
       call loadAppVar
       ld a,(appData)
       or a
       jr nz,$F
       or 1
       ret
$$:    cp 1
       jr z,silentLinkHandler
       ld hl,silentLinkHandler
       call APP_PUSH_ERRORH
       res 1,(iy+1Bh)
       res 2,(iy+1Bh)
       res 3,(iy+1Bh)
       res 4,(iy+1Bh)
       cp 2
       jr nz,$F
       ld e,0
       in a,(0)
       set 0,(iy+3Eh)
       B_CALL RejectCommand
       jr abortSilentLink
$$:    cp 3
       jr z,startTransfer
       cp 5
       jr z,startTransfer_1
       in a,(0)
       B_CALL ContinueGetByte
runProgramFromAppVar:
       B_CALL CloseEditEqu
       ld hl,appData
       rst 20h
       ld a,ProgObj
       ld (OP1),a
;       B_CALL ChkFindSym
;       jr c,abortSilentLink
;       ld a,b
;       or a
;       jr nz,abortSilentLink
;       ex de,hl
;       B_CALL ldhlind
;       push hl
;       B_CALL EnoughMem
;       pop hl
;       jr c,abortSilentLink
;       ld de,userMem
;       push hl
;       B_CALL InsertMem
;       call userMem
;       pop de
;       ld hl,userMem
;       B_CALL DelMem
       B_JUMP JForceCmdNoChar
startTransfer:
       in a,(0)
       B_CALL ContinueGetByte
startTransfer_1:
       B_CALL Get3Bytes
startTransfer_2:
       ld a,(header+1)
       cp 29h
       jr z,setLockdown
       cp 2Ah
       jr z,resetLockdown
       cp 2Bh
       jr z,setKeyEcho
       cp 2Ch
       jr z,resetKeyEcho
       cp 92h
       jr z,sendAckAndEnd
       cp 6Dh
       jr z,sendScreenshot
       cp 87h
       jr z,forceKeyPress
       cp 89h
       jr z,remoteProgramExecution
       cp 06h
       jr z,receiveVarHeader
       cp 68h
       jr nz,abortSilentLink
ackAndGetNextPacket:
       B_CALL SendAck
       B_CALL Get4BytesNC
       jr startTransfer_2
setKeyEcho:
       set 5,(iy+33h)
       jr sendAckAndEnd
resetKeyEcho:
       res 5,(iy+33h)
       jr sendAckAndEnd
setLockdown:
       res 4,(iy+33h)
       jr sendAckAndEnd
resetLockdown:
       ld a,7Bh
       call translatePage
       ld hl,_RejectCommand
       ld de,OP1
       ld bc,3
       B_CALL FlashToRam
       ld hl,(OP1)
       ld (9B78h),hl
       ld a,(OP1+2)
       ld (9B7Ah),a
       set 3,(iy+33h)
       set 4,(iy+33h)
       jr sendAckAndEnd
sendScreenshot:
       B_CALL SendScreenContents
       jr abortSilentLink
FinishReceivingDataPacket:
       ld bc,(header+2)
$$:    push bc
       B_CALL RecAByteIO
       pop bc
       dec bc
       ld a,b
       or c
       jr nz,$B
       B_CALL RecAByteIO
       B_CALL RecAByteIO
       ret
remoteProgramExecution:
       B_CALL GetSmallPacket
       B_CALL SendAck
       ld a,(appData)
       cp 5
       jr nz,abortSilentLink ;actually, run the program it sent
       jr runProgramFromAppVar
forceKeyPress:
       ld a,(header+2)
       B_JUMP JForceCmd
receiveVarHeader:
       B_CALL GetSmallPacket
       ld h,09h
       B_CALL Send4BytePacket
       B_CALL Get4BytesNC
       call FinishReceivingDataPacket
       jr ackAndGetNextPacket
sendAckAndEnd:
       B_CALL SendAck
abortSilentLink:
       call APP_POP_ERRORH
silentLinkHandler:
       res indicOnly,(iy+indicFlags)
       xor a
       ret
       ~