;
;  PROGRAM NAME:  HELP
;  AUTHOR:  RICHARD CONN
;  DATE:  18 MAY 84
;  VERSION:  5.0
;  PREVIOUS VERSIONS:  None
;  DERIVATION:  HELP2.ASM 4.1 (23 MAY 83)
;  NOTE:  FOR USE WITH ZCPR3 ONLY
;
VERS	EQU	50
Z3ENV	SET	0F400H

;
;	HELP supports an online documentation system under ZCPR3.  Refer
; to the file HELP.HLP for more details.
;

FALSE		EQU	0
TRUE		EQU	NOT FALSE

;
; USER EQUATES:
;  Set this to TRUE if all files must be of type HLP
;
FORCEHLP		EQU	TRUE 	; TRUE IF FILES MUST BE OF TYPE HLP

;
;  Directory of Help Files if HELP Directory not found
;
HDISK			EQU	'A'-'A'	; DISK
HUSER			EQU	15	; USER

;
;  Enter/Exit Standout Mode (Recommended that these values not be changed)
;
DIM			EQU	'A'-'@'	; ^A TO ENTER STANDOUT
NOTDIM			EQU	'B'-'@'	; ^B TO EXIT STANDOUT

;
;  SYSLIB ROUTINES
;
	EXT	Z3VINIT,CLS,STNDOUT,STNDEND
	EXT	GETCRT,GETPRT,PFIND,Z3LOG,DIRTDU
	EXT	CODEND
	EXT	LOGUD,RETUD,PUTUD,GETUD
	EXT	EPSTR,EPRINT,COUT,CIN,CAPS,PFN2,PAFDC
	EXT	INITFCB,F$EXIST,F$OPEN,F$READ,F$CLOSE

;
;  CP/M Constants
;
UDFLAG		EQU	4	; ADDRESS OF USER/DISK FLAG
BDOS		EQU	5	; ADDRESS OF BDOS ENTRY POINT
FCB		EQU	5CH	; ADDRESS OF FILE CONTROL BLOCK
BUFF		EQU	80H	; ADDRESS OF DMA BUFFER

CR		EQU	0DH	; <CR>
LF		EQU	0AH	; <LF>
BEL		EQU	'G'-'@'	; ^G
FF		EQU	'L'-'@'	; ^L = FORM FEED
CTRLZ		EQU	'Z'-'@'	; ^Z
CTRLC		EQU	'C'-'@'	; ^C

;
;  HELP Control Characters
;
IHCHAR		EQU	';'	; FLAG INDICATING INDEXED BY USER
SECTCHAR	EQU	':'	; DEFINED TO BE COLON
BACKUPCHAR	EQU	'L'	; BACK UP TO PREVIOUS FRAME CHAR
STRTCHAR	EQU	'S'	; JUMP TO START OF INFORMATION CHAR
MENUCHAR	EQU	'M'	; CHAR TO ABORT TO MENU
CPMABORTCHAR	EQU	CTRLC	; CHAR TO EXIT
LRCHAR		EQU	'^'	; RETURN TO PREVIOUS HELP LEVEL
ROOTCHAR	EQU	'.'	; RETURN TO ROOT OF HELP
PRCHAR		EQU	'P'	; PRINT CURRENT FRAME
CPRCHAR		EQU	'P'-'@'	; PRINT CURRENT INFORMATION SECTION

;
; Environment Definition
;
	if	z3env ne 0
;
; External ZCPR3 Environment Descriptor
;
	jmp	start
	db	'Z3ENV'	;This is a ZCPR3 Utility
	db	1	;External Environment Descriptor
z3eadr:
	dw	z3env
start:
	lhld	z3eadr	;pt to ZCPR3 environment
;
	else
;
; Internal ZCPR3 Environment Descriptor
;
	MACLIB	Z3BASE.LIB
	MACLIB	SYSENV.LIB
z3eadr:
	jmp	start
	SYSENV
start:
	lxi	h,z3eadr	;pt to ZCPR3 environment
	endif

;
; Start of Program -- Initialize ZCPR3 Environment
;
	call	z3vinit	;initialize the ZCPR3 Env and the VLIB Env
	jmp	startx
;
;  DEFAULT FILE NAME
;
HELPDIR:
DEFFN:
	DB	'HELP    '	; BOTH HELP FILE AND HELP DIR SAME NAME
DEFTYP:
	DB	'HLP'

;
;  Start of Program
;
STARTX:
	LXI	H,0	; GET SP
	DAD	SP
	SHLD	STACK
	CALL	CODEND	; DETERMINE FREE MEMORY SPACE
	SHLD	HLPNSTK	; SET PTR TO HELP NAME STACK
	LXI	D,200H	; ALLOW 25+ ELEMENT HELP NAME STACK AND LARGE STACK
	DAD	D
	SHLD	HLPBUF
	SPHL		; SET STACK

	LDA	BDOS+2	; BASE PAGE OF BDOS
	SUI	10	; 2K + 2 PAGES
	STA	TPAEND

	XRA	A	; A=0
	STA	HLPLVL	; SET HELP LEVEL TO 0 (NO RETURN FILE)

	LXI	D,FCB	; PT TO FCB
	CALL	Z3LOG	; LOG INTO IT FOR DEFAULT
	CALL	PUTUD	; SAVE HOME

	LXI	H,FCB+1	; CHECK FOR FILE NAME
	MOV	A,M
	CPI	'/'	; OPTION CAUGHT?
	JZ	STRT0
	CPI	' '	; NONE?
	JNZ	STRT1
;
;  INSERT 'HELP.HLP' INTO FCB OR CLEAR FCB
;
STRT0:
	LXI	D,DEFFN	; PT TO DEFAULT NAME
	MVI	B,11	; 11 BYTES
	XCHG
	CALL	MOVE	; MOVE (HL) TO (DE) FOR (B) BYTES

;
;  START/RESTART HELP PROGRAM (START ON INITIAL ENTRY, RESTART ON NODE LOAD)
;
STRT1:
	LHLD	HLPBUF	; RESET STACK
	SPHL
;
;  CHECK FOR WILD CARDS IN FILE NAME -- ERROR IF SO
;
	LXI	H,FCB+1	; PT TO FIRST BYTE OF FILE NAME
	MVI	B,11	; 11 BYTES
FCBWCK:
	MOV	A,M	; GET BYTE
	ANI	7FH	; MASK
	CPI	'?'	; WILD?
	JZ	FCBWERR
	INX	H	; PT TO NEXT
	DCR	B
	JNZ	FCBWCK
;
;  CHECK FOR FILE TYPE
;
	LXI	H,FCB+9	; CHECK FOR FILE TYPE

	IF	NOT FORCEHLP
	MOV	A,M	; CHECK FOR FILE TYPE SPECIFIED
	CPI	' '	; NONE?
	JNZ	STRT2
	ENDIF
;
;  PLACE DEFAULT FILE TYPE OF '.HLP' IN FCB
;
	LXI	D,DEFTYP	; DEFAULT FILE TYPE
	MVI	B,3
	XCHG
	CALL	MOVE	; MOVE (HL) TO (DE) FOR (B) BYTES

;
;  FIND FILE
;
STRT2:
;
;  LOOK INTO DIRECTORY PTED TO BY USER (OR CURRENT IF USER DID NOT SPEC ONE)
;
	LXI	D,FCB		; PT TO FCB
;	CALL	Z3LOG		; LOG INTO DIRECTORY
	CALL	INITFCB		; RESET FCB
	CALL	RETUD		; GET HOME LOCATION
	CALL	F$EXIST		; IS FILE THERE?
	JNZ	STRT3
;
;  LOOK ALONG PATH FROM CURRENT DIR (NOT INCLUDING CURRENT)
;
	CALL	GETUD		; RETURN HOME
	LXI	D,FCB		; PT TO FCB
	MVI	A,0		; DON'T SEARCH CURRENT DIR ALSO
	CALL	PFIND		; SEARCH FOR FILE
	JNZ	STRT3		; FILE FOUND, SO PROCESS
;
;  LOOK IN HELP FILE DIRECTORY
;
	LXI	H,HELPDIR	; LOOK FOR HELP DIRECTORY
	CALL	DIRTDU		; CONVERT TO DU IN BC
	JNZ	LOGHLP		; LOG INTO DU IN BC IF FOUND
	MVI	B,HDISK		; LOG INTO HELP DIRECTORY
	MVI	C,HUSER
LOGHLP:
	CALL	LOGUD
	LXI	D,FCB		; PT TO FCB
	CALL	F$EXIST		; LOOK FOR FILE
	JNZ	STRT3		; FILE FOUND
;
;  FILE NOT FOUND
;
	CALL	EPRINT
	DB	CR,LF,' File Not Found',0
	JMP	HLPEXIT

;
;  FILE CONTAINS WILD CARDS
;
FCBWERR:
	CALL	EPRINT
	DB	CR,LF,' AFN Not Allowed',0
	JMP	HLPEXIT

;
;  LOAD HELP FILE INFORMATION
;	ON INPUT, BC=DIRECTORY
;
STRT3:
	CALL	LOGUD		; LOG INTO DIRECTORY
	LXI	D,FCB		; OPEN FILE
	CALL	F$OPEN
	LHLD	HLPBUF	; PT TO BUFFER
	SHLD	NEXTADR	; SET PTR
;
;  READ RECORDS UNTIL EOF
;
STRT4:
	CALL	READ	; READ INFO
	JZ	STRT4	; NOT DONE IF ZERO RETURN
	LXI	D,FCB	; CLOSE FILE
	CALL	F$CLOSE
	CALL	GETUD	; RESTORE CURRENT DISK AND USER IF CHANGED

;
;  START OF HELP PROGRAM
;
HELP:
	LHLD	HLPBUF	; PT TO BUFFER
	SPHL		; SET STACK
	MVI	A,0	; SET NO FRAME
	STA	FRNUM
	MOV	A,M	; NO HEADER SECTION?
	ANI	7FH	; MASK OUT MSB
	CPI	SECTCHAR
	JNZ	HELP1	; HEADER SECTION EXISTS
	CALL	CLS	; NEW SCREEN
	CALL	PRINFO	; PRINT HELP INFO PTED TO BY HL
	LDA	HLPLVL	; CHECK TO SEE IF WE ARE NOT AT LEVEL 0
	ORA	A	; 0=LEVEL 0
	JZ	HLPEXIT	; ABORT IF SO
	JMP	LRURN	; GO TO PREVIOUS LEVEL IF NOT

;
;  EXIT POINT FOR ANY EXIT FROM THE REST OF THE HELP PROGRAM
;
HLPEXIT:
	CALL	GETUD	; RESET CALLING DISK/USER NUMBER
	LHLD	STACK	; GET CP/M SP
	SPHL
	RET		; DONE

;
;  PRINT HEADER INFORMATION AND SELECT AN OPTION
;
HELP1:
	CALL	PRHEADER	; PRINT HEADER
	PUSH	B		; SAVE C (NUMBER OF VALID SELECTIONS)
	CALL	CRLF1		; NEW LINE
	CALL	STNDOUT		; GOTO DIM
	CALL	PRLEVEL		; PRINT LEVEL NUMBER
	CALL	EPRINT
	DB	'Enter Selection  ',0
	CALL	PRP1		; PRINT LEVEL MOVEMENT PROMPT
	CALL	STNDEND		; GOTO BRIGHT
	POP	B		; GET C
	CALL	CIN		; GET RESPONSE
	CALL	CAPS		; CAPITALIZE
	PUSH	PSW
	CALL	CLS		; CLEAR SCREEN
	POP	PSW
	CPI	CTRLC		; EXIT
	JZ	HLPEXIT
	CPI	ROOTCHAR	; GO TO ROOT
	JZ	GOROOT
	CPI	LRCHAR		; RETURN TO PREVIOUS LEVEL
	JZ	LRURN
	MOV	B,A		; USER INPUT IN B
	LDA	HTYPE		; TYPE OF HELP FILE
	CPI	IHCHAR		; INDEXED BY USER?
	JZ	HELP5		; FIND INFORMATION SECTION VIA INDEX SCAN
	MOV	A,B		; FIND INFORMATION SECITON VIA COUNT
	SUI	'A'-1		; ADJUST FOR COUNT
	MOV	B,A		; SAVE COUNT
	JZ	BADRESPONSE
	JNC	HELP2
;
;  INVALID RESPONSE
;
BADRESPONSE:
	CALL	SAK		; RING BELL
	JMP	HELP1

;
;  VALID RESPONSE -- LOOK FOR AND PRINT INFORMATION SECTION
;
HELP2:
	INR	C		; 1 MORE THAN NUMBER OF POSSIBLE SELECTIONS
	CMP	C		; GREATER THAN NUMBER OF POSSIBLE SELECTIONS?
	JNC	BADRESPONSE
	LHLD	FIRSTENTRY	; GET PTR TO FIRST ENTRY

;
;  PRINT INFORMATION WHEN COUNT IS ZERO
;
HELP3:
	DCR	B	; COUNT DOWN SELECTIONS
	JNZ	HELP4
	CALL	PRINFO	; PRINT INFO PTED TO BY HL
	JMP	HELP1
;
;  LOCATE NEXT INFORMATION SECTION
;
HELP4:
	CALL	FINDI	; SKIP TO NEXT INFORMATION SECTION
	CPI	CTRLZ	; END OF FILE?
	JNZ	HELP3	; CONTINUE LOOPING IF NOT ELSE FALL THRU TO HELPERR
;
;  ERROR -- REACHED END OF HELP FILE
;
HELPERR:
	CALL	EPRINT
	DB	CR,LF,' EOF on Help File',0
	JMP	HELP1

;
;  LOCATE NEXT INFORMATION SECTION VIA INDEX SCAN
;
HELP5:
	LHLD	FIRSTENTRY	; PT TO FIRST ENTRY
;
;  LOOK FOR USER INDEX
;
HELP6:
	PUSH	H		; SAVE PTR TO THIS LINE
HELP7:
	INX	H		; SKIP OVER SECTION CHAR
	MOV	A,M		; GET CHAR
	ANI	7FH		; MASK OUT MSB
	CALL	CAPS		; CAPITALIZE
	CPI	' '		; SKIP SPACES
	JZ	HELP7
	CPI	SECTCHAR	; NEW SECTION?
	JZ	HELP8		; FIND NEXT SECTION
	CPI	CR		; END OF LINE?
	JZ	HELP8		; FIND NEXT SECTION
	CPI	CTRLZ		; EOF?
	JZ	HELP8
	CMP	B		; CHECK FOR USER INPUT
	JNZ	HELP7
	POP	H		; FOUND IT -- PRINT IT
	INX	H		; SKIP OVER SECTION CHAR
HELP7A:
	MOV	A,M		; SKIP TO BEGINNING FOR 1ST LINE
	INX	H		; PT TO NEXT
	ANI	7FH
	CPI	CTRLZ		; TRAP EOF
	JZ	BADRESPONSE
	CPI	SECTCHAR	; FILE SPECIFIED?
	JZ	HELP7B		; PROCESS IT
	CPI	LF		; BEGIN NEW LINE
	JZ	HELP7C
	CPI	CR		; AT END OF INDEX LINE?
	JNZ	HELP7A
	MOV	A,M		; GET LF
	ANI	7FH
	CPI	LF		; SKIP FOLLOWING LF IF ANY
	JNZ	HELP7C
	INX	H		; SKIP LF
	JMP	HELP7C
;
;  LOAD NEXT HELP LEVEL
;
HELP7B:
	DCX	H		; PT TO SECTION CHAR
	DCX	H		; PT TO BEFORE SECTION CHAR FOR PRINFO
;
;  PROCESS HELP LEVEL OR LOAD AND PROCESS NEXT LEVEL PTED TO BY HL
;
HELP7C:
	CALL	PRINFO		; PRINT INFORMATION SECTION
	JMP	HELP1		; RESUME
HELP8:
	POP	H		; PT TO INFO SECTION
	CALL	FINDI		; FIND NEXT INFO SECTION
	CPI	CTRLZ		; EOF?
	JNZ	HELP6		; KEEP LOOKING
	JMP	BADRESPONSE

;
;  SKIP TO NEXT INFORMATION SECTIONS
;    RETURN WITH A=SECTCHAR IF FOUND OR A=^Z IF NOT
;
FINDI:
	MOV	A,M	; <CTRL-Z>?
	ANI	7FH	; MASK OUT MSB
	INX	H	; PT TO NEXT BYTE
	CPI	CTRLZ
	RZ
	CPI	LF	; LINE FEED?
	JZ	FINDI1
	CPI	CR	; <CR>?
	JNZ	FINDI
	MOV	A,M	; MAKE SURE LF
	ANI	7FH
	CPI	LF
	JNZ	FINDI1
	INX	H	; SKIP OVER LF
FINDI1:
	MOV	A,M	; GET CHAR
	ANI	7FH	; MASK OUT MSB
	CPI	SECTCHAR	; NEW SECTION?
	JNZ	FINDI	; CONTINUE LOOPING
	RET

;
;  HELP SUPPORT ROUTINE SECTION
;

;
;  PRINT ERROR MSG PTED TO BY DE; ENDS IN 0
;
PRMSG:
	XCHG		; MSG PTED TO BY HL
	CALL	EPSTR
	XCHG
	RET

;
;  MOVE BYTES PTED TO BY HL TO AREA PTED TO BY DE; B BYTES TO MOVE
;
MOVE:
	MOV	A,M	; GET BYTE
	ANI	7FH	; MASK OFF MSB -- IN CASE A WS FILE
	STAX	D	; PUT BYTE
	INX	H	; PT TO NEXT
	INX	D
	DCR	B
	JNZ	MOVE
	RET

;
;  READ RECORD FROM DISK; NEXTADR CONTAINS ADDRESS TO READ TO
;	ON RETURN, BDOS ERROR CODE IS IN A (0=NO ERROR)
;
READ:
	LXI	D,FCB	; PT TO FCB
	CALL	F$READ	; READ NEXT RECORD
	PUSH	PSW	; SAVE RETURN CODE
	LHLD	NEXTADR	; PT TO LOAD ADDRESS
	LDA	TPAEND	; CHECK AGAINST END PAGE OF TPA
	CMP	H	; IF AT SAME PAGE, YES
	JZ	READERROR
	LXI	D,BUFF	; PT TO BUFFER TO LOAD FROM
	MVI	B,128	; NUMBER OF BYTES TO MOVE
	XCHG
	CALL	MOVE
	XCHG
	MVI	M,CTRLZ	; STORE ENDING CTRLZ IN CASE OF EOF
	POP	PSW	; GET RETURN CODE
	ORA	A	; DONE?  <>0 IF SO
;
;  READ DONE -- SAVE PTR TO NEXT BLOCK
;
	SHLD	NEXTADR	; SET NEXT ADDRESS
	RET

READERROR:
	CALL	EPRINT
	DB	CR,LF,' Mem Full',0
	JMP	HLPEXIT

;
;  PRINT ONE LINE OF INFO SECTION; HL PTS TO LINE UPON ENTRY;
;	HL PTS TO FIRST CHAR OF NEXT LINE UPON EXIT
;
PRLINE:
	MOV	A,M	; GET CHAR
	ANI	7FH	; MASK OUT MSB
	CPI	CR	; EOL?
	JZ	CRLF
	CPI	LF	; LINE FEED? (WS FILE)
	JZ	CRLF0
	CPI	CTRLZ	; END OF FILE?
	JZ	CRLFC	; DONE IF SO
	INX	H	; PT TO NEXT
	CPI	DIM	; GOTO STANDOUT MODE?
	JZ	PRLDIM
	CPI	NOTDIM	; GOTO NORMAL MODE?
	JZ	PRLNDIM
	CALL	COUT	; PRINT CHAR
	JMP	PRLINE
PRLDIM:
	CALL	STNDOUT	; ENTER STANDOUT MODE
	JMP	PRLINE
PRLNDIM:
	CALL	STNDEND	; END STANDOUT MODE
	JMP	PRLINE
;
;  PRINT CRLF, PT TO FIRST CHAR OF NEXT LINE, AND PAGE IF NECESSARY
;
CRLF:
	INX	H	; PT TO LF
CRLF0:
	INX	H	; PT TO 1ST CHAR OF NEXT LINE
CRLFC:
	CALL	CRLF1	; PRINT CRLF
	LDA	LCOUNT	; GET LINE COUNT
	DCR	A
	STA	LCOUNT
	RNZ		; OK -- CONTINUE
	MOV	A,M	; SET MSB OF FIRST CHAR OF NEXT LINE
	ORI	80H
	MOV	M,A	; MSB IS SET FOR LATER BACKUP
	CALL	PRPROMPT	; PRINT PROMPT AND PROCESS COMMON OPTIONS
	CPI	BACKUPCHAR	; BACK UP?
	JZ	FBACKUP
	CPI	STRTCHAR	; JUMP TO START OF INFO
	JZ	INFOSTRT
FRESUME:
	SHLD	STRTFRAME
	JMP	SETLCOUNT
;
;  PRINT PROMPT AND PROCESS COMMON OPTIONS
;
PRPROMPT:
	CALL	STNDOUT	; GOTO DIM
	CALL	PRLEVEL	; PRINT LEVEL NUMBER
	LDA	FRNUM	; INCREMENT FRAME NUMBER
	INR	A
	STA	FRNUM
	CALL	PRP1	; PRINT FUNDAMENTAL LEVEL DATA PROMPT
	CALL	EPRINT
	DB	MENUCHAR,'=Menu '	; ABORT TO MENU CHAR
	DB	STRTCHAR,'=Start '	; JUMP TO START OF INFORMATION CHAR
	DB	BACKUPCHAR,'=Last '	; BACK UP TO PREVIOUS FRAME CHAR
	DB	PRCHAR,'=Print '	; PRINT CURRENT FRAME
	DB	0
	CALL	STNDEND	; GOTO BRIGHT
	CALL	CIN	; GET RESPONSE
	CALL	CAPS
	PUSH	PSW
	CALL	CLS		; CLEAR SCREEN
	POP	PSW
	POP	D		; CLEAR STACK
	CPI	MENUCHAR	; ABORT?
	JZ	HELP		; START OVER IF SO
	CPI	CPMABORTCHAR	; ABORT TO OS
	JZ	HLPEXIT
	CPI	PRCHAR		; PRINT FRAME?
	JZ	LIST0INFO
	CPI	CPRCHAR		; PRINT INFORMATION SECTION?
	JZ	LIST1INFO
	CPI	ROOTCHAR	; GO TO ROOT
	JZ	GOROOT
	CPI	LRCHAR		; RETURN TO HIGHER LEVEL
	JZ	LRURN
	PUSH	D		; RESTORE STACK
	RET

;
;  PRINT FUNDAMENTAL LEVEL PROMPT
;
PRP1:
	LDA	HLPLVL		; DON'T PRINT IF AT LEVEL 0
	ORA	A
	RZ
	CALL	EPRINT
	DB	LRCHAR,'=Level '	; RETURN TO HIGHER NODE
	DB	ROOTCHAR,'=Root '		; RETURN TO ROOT
	DB	0
	RET

;
;  JUMP TO START OF INFORMATION
;
INFOSTRT:
	LHLD	STRTINFO	; PT TO START OF INFO
	MVI	A,1		; RESET FRAME COUNT
	STA	FRNUM
	JMP	FRESUME	; CONTINUE PROCESSING

;
;  BACK UP TO PREVIOUS FRAME
;
FBACKUP:
	CALL	BOICHECK	; AT BEGINNING OF INFORMATION?
	JZ	INFOSTRT
FB1:
	DCX	H	; BACK UP UNTIL BYTE WITH MSB SET IS FOUND
	MOV	A,M	; GET BYTE
	ANI	80H
	JZ	FB1
	LDA	FRNUM	; DECREMENT FRAME NUMBER
	DCR	A		; BACK UP TO CURRENT FRAME NUMBER
	DCR	A		; BACK UP TO PREVIOUS FRAME NUMBER
	STA	FRNUM
	JMP	FRESUME	; CONTINUE PROCESSING
;
;  PRINT CR AND LF ONLY
;
CRLF1:
	MVI	A,CR	; PRINT CR
	CALL	COUT
	MVI	A,LF	; PRINT LF
	JMP	COUT

;
;  SET LCOUNT VARIABLE TO SCREEN SIZE
;
SETLCOUNT:
	PUSH	H	; SAVE HL
	CALL	GETCRT	; GET CRT DATA
	INX	H	; PT TO LINE COUNT
	MOV	A,M	; GET LINE COUNT
	POP	H	; RESTORE HL
	DCR	A	; 1 LESS FOR PROMPT
	STA	LCOUNT
	RET

;
;  PRINT THE HEADER SECTION AND LOAD FIRSTENTRY PTR
;    ON RETURN, C=NUMBER OF POSSIBLE SELECTIONS
;
PRHEADER:
	MVI	A,0	; SET NO FRAME
	STA	FRNUM
	CALL	SETLCOUNT
	LDA	LCOUNT
	SUI	3	; -3 lines for top and bottom
	STA	LCOUNT
	MVI	A,'A'	; INIT SELECTION CHAR
	STA	SELCHAR
	CALL	CLS	; CLEAR SCREEN
	CALL	EPRINT
	DB	'HELP '
	db	(vers/10)+'0','.',(vers mod 10)+'0'
	DB	'    ',0
	LXI	D,FCB+1	; PT TO FCB
	CALL	PFN2	; PRINT WITH NO SPACES
	CALL	EPRINT
	db	' Index',CR,LF,CR,LF,0
	MVI	C,0	; COUNT NUMBER OF SELECTIONS
	LHLD	HLPBUF	; PT TO BUFFER
	MOV	A,M	; GET FIRST CHAR
	STA	HTYPE	; SET TYPE OF HELP FILE
	CPI	IHCHAR	; INDEXED HELP TYPE?
	JNZ	PH1
	INX	H	; SKIP OVER INDEX HELP TYPE FLAG
;
; PRINT LINE UNTIL FIRST INFORMATION SECTION FOUND
;
PH1:
	MOV	A,M	; GET CHAR
	ANI	7FH	; MASK OUT MSB
	CPI	SECTCHAR
	JZ	PH2
	CPI	CTRLZ	; EOF? -- ABORT
	JZ	HLPEXIT
	INR	C	; INCREMENT SELECTION COUNT
	LDA	HTYPE	; CHECK FOR INDEX
	CPI	IHCHAR
	JZ	PH1A	; SKIP LETTERS IF INDEXED
	LDA	SELCHAR	; DISPLAY SELECTION CHAR
	CALL	COUT
	INR	A	; INCR CHAR
	STA	SELCHAR
	CALL	EPRINT
	DB	'. ',0
PH1A:
	CALL	PRLINE	; PRINT HEADER LINE
	JMP	PH1
;
;  SAVE PTR TO FIRST ENTRY
;
PH2:
	SHLD	FIRSTENTRY
	LDA	LCOUNT		; GET COUNT OF REMAINING LINES
	MOV	B,A		; ... IN B
	ORA	A		; ANY LEFT?
	RZ
PH3:
	CALL	CRLF1		; NEW LINE
	DCR	B
	JNZ	PH3
	RET

;
;  PRINT AN INFORMATION SECTION
;    INFORMATION SECTION IS PTED TO BY HL
;
PRINFO:
	SHLD	STRTINFO	; SET START OF INFORMATION POINTER
	CALL	LDNOD	; LOAD NEW NODE IF DUAL SECTCHAR
	SHLD	STRTFRAME	; SET FRAME POINTER
	MOV	A,M	; SET MSB
	ORI	80H
	MOV	M,A
	CALL	SETLCOUNT
	MVI	A,1		; A=1
	STA	FRNUM	; SET FRAME NUMBER
PI1:
	CALL	PRLINE	; PRINT LINE FROM INFO FILE
	MOV	A,M	; DONE?
	ANI	7FH	; MASK OUT MSB
	CPI	CTRLZ	; EOF?
	JZ	PI2
	CPI	SECTCHAR	; NEXT SECTION
	JZ	PI2
	CPI	FF	; FORM FEED?
	JNZ	PI1
	INX	H	; PT TO CHAR AFTER FORM FEED
	CALL	FORMFEED	; FEED SCREEN
	JMP	PI1
;
;  FORM FEED SCREEN
;
FORMFEED:
	LDA	LCOUNT	; GET LINE COUNT
	MOV	B,A	; ... IN B
FEEDLOOP:
	PUSH	B	; SAVE B
	CALL	CRLFC	; NEW LINE
	POP	B	; GET B
	DCR	B
	JNZ	FEEDLOOP
	RET

;
;  END OF INFO
;
PI2:
	MOV	A,M	; SET MSB OF NEXT BYTE
	ORI	80H
	MOV	M,A
PI2A:
	CALL	CRLF1	; NEW LINE
	LDA	LCOUNT		; COUNT DOWN
	DCR	A
	STA	LCOUNT
	JNZ	PI2A
PI2MSG:
	CALL	EPRINT		; PRINT END OF INFORMATION INDICATOR
	DB	'EOI ',0
	CALL	PRPROMPT	; PRINT PROMPT AND PROCESS COMMON OPTIONS
	CPI	BACKUPCHAR	; BACK UP FROM EOI?
	JZ	PI2BACKUP
	CPI	STRTCHAR	; START OF INFO?
	JZ	PI2STRT
	JMP	SETLCOUNT	; RESET LINE COUNT IN CASE OF ALL

;
;  JUMP TO START OF INFO FROM EOI
;
PI2STRT:
	LHLD	STRTINFO	; PT TO START OF INFO
	CALL	FRESUME	; RESET POINTERS
	MVI	A,1		; RESET FRAME COUNT
	STA	FRNUM
	JMP	PI1		; CONTINUE PROCESSING

;
;  BACK UP TO PREVIOUS FRAME FROM EOI
;
PI2BACKUP:
	CALL	BOICHECK	; AT BEGINNING OF INFORMATION?
	JZ	PI2STRT
PI2BACK:
	CALL	FB1		; BACK UP TO PREVIOUS FRAME
	JMP	PI1		; CONTINUE PROCESSING

;
;  CHECK FOR POSITION AT BEGINNING OF INFORMATION SECTION
;    IF SO, PRINT BACKUP ERROR MSG AND RETURN W/ZERO SET
;
BOICHECK:
	LHLD	STRTINFO	; START ADDRESS
	XCHG			; ... IN DE
	LHLD	STRTFRAME	; FRAME ADDRESS
	MOV	A,D		; EQUAL?
	CMP	H
	RNZ
	MOV	A,E
	CMP	L
	RNZ
	CALL	SAK		; ERROR BELL
	XRA	A		; ZERO FLAG SET
	STA	FRNUM		; SET FRAME NUMBER
	RET

;
;  THIS BODY OF CODE LISTS INFORMATION FROM HELP2 TO THE
;  PRINTER
;

;
;  LIST ONE LINE OF INFO SECTION; HL PTS TO LINE UPON ENTRY;
;	HL PTS TO FIRST CHAR OF NEXT LINE UPON EXIT
;
LISTLINE:
	MOV	A,M	; GET CHAR
	ANI	7FH	; MASK OUT MSB
	CPI	CR	; EOL?
	JZ	LCRLF
	CPI	LF	; LINE FEED? (WS FILE)
	JZ	LCRLF0
	CPI	CTRLZ	; END OF FILE?
	JZ	LCRLFC	; DONE IF SO
	CALL	LSTOUT	; PRINT CHAR
	RZ		; ABORT
	INX	H	; PT TO NEXT
	JMP	LISTLINE

;
;  LIST CRLF, PT TO FIRST CHAR OF NEXT LINE, AND PAGE IF NECESSARY
;
LCRLF:
	INX	H	; PT TO LF
LCRLF0:
	INX	H	; PT TO 1ST CHAR OF NEXT LINE
LCRLFC:
	CALL	LCRLF1	; PRINT CRLF
	LDA	LCOUNT	; GET LINE COUNT
	DCR	A
	STA	LCOUNT
	JNZ	LNOABT	; OK -- CONTINUE
	CALL	LFORMFEED	; ADVANCE TO NEXT PAGE
SETPLC:
	PUSH	H	; SAVE HL
	CALL	GETPRT	; GET PRINTER DATA
	INX	H	; PT TO TEXT LINE COUNT
	INX	H
	MOV	A,M	; GET TEXT LINE COUNT
	STA	LCOUNT	; SET LINE COUNT
	POP	H	; RESTORE HL
	RET
LCRLF1:
	MVI	A,CR	; SEND <CRLF> TO PRINTER
	CALL	LSTOUT
	RZ		; ABORT
	MVI	A,LF	; FALL THRU TO LSTOUT

;
;  PRINT CHARACTER IN A ON PRINTER; AFFECT NO REGISTERS
;
LSTOUT:
	PUSH	H	; SAVE REGS
	PUSH	D
	PUSH	B
	MOV	E,A	; CHAR IN E
	MVI	C,5	; BDOS PRER OUTPUT ROUTINE
	CALL	BDOS
	MVI	E,0FFH	; CONDITIONAL INPUT
	MVI	C,6	; DIRECT CONSOLE I/O
	CALL	BDOS
	POP	B	; RESTORE REGS
	POP	D
	POP	H
	CPI	CTRLC	; ABORT?
	RET
LNOABT:
	MVI	A,0FFH	; SET NO ABORT RETURN
	ORA	A	; SET FLAGS
	RET

;
;  LIST THE CURRENT INFORMATION SECTION
;    INFORMATION SECTION IS PTED TO BY STRTINFO
;
;  LIST0INFO -- LIST CURRENT FRAME ONLY
;  LIST1INFO -- LIST CURRENT INFORMATION SECTION
;
LIST0INFO:
	LHLD	STRTFRAME	; LIST CURRENT FRAME ONLY
	MVI	A,0FFH		; SET FLAG
	STA	LFRFLAG		; LIST FRAME ONLY
	JMP	LIST2INFO
LIST1INFO:
	LHLD	STRTINFO	; PREPARE TO LIST ENTIRE INFO SECTION
	XRA	A		; CLEAR FRAME LIST FLAG
	STA	LFRFLAG
LIST2INFO:
	CALL	LISTINFO	; DO PRINT
	CALL	CLS		; CLEAR SCREEN
	CALL	LFORMFEED	; FORM FEED PRINTER
	LHLD	STRTFRAME	; RETURN TO FRAME WE WERE ON
	CALL	FRESUME
	LDA	FRNUM		; ADJUST FRAME NUMBERING
	DCR	A
	STA	FRNUM
	JMP	PI1		; RESUME AT PI1
;
;  MAIN PRINT ROUTINE
;
LISTINFO:
	CALL	CLS		; PRINT FRAME OR INFO SECTION
	CALL	EPRINT
	DB	CR,LF,' Printing ',0
	CALL	SETPLC		; SET PRINTER LINE COUNT
LI1:
	CALL	LISTLINE	; LIST LINE FROM INFO FILE
	CPI	CTRLC		; ABORT?
	RZ			; FEED PRINTER AND EXIT
	MOV	A,M		; DONE?
	ANI	7FH		; MASK OUT MSB
	CPI	CTRLZ		; EOF?
	RZ			; RESUME IF AT END OF INFO
	CPI	SECTCHAR	; NEXT SECTION
	RZ			; RESUME IF AT END OF INFO
	CPI	FF		; FORM FEED?
	JNZ	LI1
	LDA	LFRFLAG		; LIST FRAME ONLY?
	ORA	A		; 0=NO
	RNZ
	INX	H		; PT TO CHAR AFTER FORM FEED
	CALL	LCRLFC		; NEW LINE
	MVI	B,10		; PRINT SEPARATOR
LI2:
	MVI	A,'-'		; DASHES
	CALL	LSTOUT
	RZ			; ABORT?
	DCR	B		; COUNT DOWN
	JNZ	LI2
	CALL	LCRLFC		; 2 NEW LINES
	CALL	LCRLFC
	JMP	LI1

;
;  FORM FEED PRINTER
;
LFORMFEED:
	CALL	LCRLF1	; NEW LINE
	MVI	A,FF	; OUTPUT FORM FEED
	CALL	LSTOUT
	JMP	SETPLC	; RESET LINE COUNT

;
;  END OF BODY OF CODE WHICH LISTS INFORMATION FROM HELP2 TO
;  THE PRINTER
;

;
;  AT THE BEGINNING OF AN INFORMATION SECTION (HL PTS TO FIRST CHAR)
;    CHECK TO SEE IF ANOTHER SECTCHAR FOLLOWS, AND, IF SO, LOAD THE
;    SPECIFIED FILE AS A NEW NODE AND BEGIN PROCESSING IT
;
LDNOD:
	INX	H	; PT TO POSSIBLE 2ND SECTCHAR
	MOV	A,M	; GET IT
	DCX	H	; PREP FOR RETURN
	ANI	7FH	; MASK MSB
	CPI	SECTCHAR	; ANOTHER ONE?
	RNZ		; PROCESS NORMALLY IF NOT
;
;  WE HAVE A NEW NODE -- CHECK TO SEE IF WE CAN NEST AGAIN
;
	LDA	HLPLVL	; GET CURRENT HELP LEVEL
	CPI	25	; AT MAXIMUM?
	JNZ	LDNOD1
	CALL	CLS	; NEW SCREEN
	CALL	EPRINT
	db	cr,lf,' Node Level Limit',0
	JMP	HLPEXIT

;
;  WE HAVE NOT REACHED LEVEL LIMIT, SO CONTINUE
;  AT THIS TIME, A=HELP LEVEL INDEX AND HL = PTR TO CURRENT SECTION (::)
;
LDNOD1:
;
;  SAVE CURRENT HELP FILE NAME FOR RETURN
;
	INX	H	; PT TO SECTION SECTCHAR
	INX	H	; NOW POINTING TO FILE NAME
	PUSH	H	; SAVE PTR
	CALL	COMPTR	; HL=POINTER TO STACK ELT INDEXED BY A
	XCHG		; DE=ADDRESS OF NEXT ELEMENT
;
;  COPY CURRENT NODE ELEMENT NAME INTO NEXT STACK ELEMENT
;
	LXI	H,FCB+1	; PT TO FILE NAME
	MVI	B,11	; 11 BYTES
	CALL	MOVE
;
;  INCREMENT HELP LEVEL
;
	LDA	HLPLVL	; GET OLD LEVEL
	INR	A	; SET NEW LEVEL
	STA	HLPLVL
;
;  SET UP FCB FOR NEW FILE
;
	POP	H	; GET PTR TO NEW FILE NAME
	LXI	D,FCB+1	; PT TO FCB NAME
	MVI	B,8	; 8 CHARS MAX
	CALL	LDFCB	; PLACE INTO FCB WITH ERROR CHECKING
	MVI	B,3	; 3 CHARS MAX FOR TYPE
	CPI	'.'	; CONTINUE IF FILE TYPE PRESENT
	CZ	LDFCB	; PLACE INTO FCB WITH ERROR CHECKING
;
;  PRINT LOADING HELP FILE MESSAGE
;
PLHFM:
	CALL	EPRINT
	DB	CR,LF,' Loading HELP File ',0
	LXI	D,FCB+1	; PRINT FILE NAME
	CALL	PFN2
	JMP	STRT1	; LOAD NEW HELP FILE

;
;  LOAD FCB PTED TO BY DE WITH "NORMAL" FILE NAME PTED TO BY HL FOR B BYTES
;
LDFCB:
	MOV	A,M	; GET CHAR
	INX	H	; PT TO NEXT
	CPI	'.'	; DONE IF DECIMAL
	JZ	LDFCB2
	CPI	' '+1	; DONE IF <= <SP>
	JC	LDFCB2
	CALL	CAPS	; CAPITALIZE
	STAX	D	; STORE CHAR
	INX	D	; PT TO NEXT
	DCR	B
	JNZ	LDFCB
LDFCB1:
	MOV	A,M	; CHECK FOR ERROR
	ANI	7FH	; MASK MSB
	INX	H	; PT TO NEXT CHAR
	CPI	'.'	; OK IF '.'
	RZ
	CPI	' '+1	; OK IF <= <SP>
	RC
	JMP	LDFCB1
LDFCB2:
	MOV	C,A	; SAVE CHAR THAT TERMINATED STRING
LDFCB3:
	MVI	A,' '	; <SP> FILL REST OF FCB
	STAX	D	; STORE <SP>
	INX	D	; PT TO NEXT
	DCR	B
	JNZ	LDFCB3
	MOV	A,C	; GET CHAR THAT TERMINATED STRING
	RET

;
;  GO TO ROOT
;
GOROOT:
	LDA	HLPLVL	; AT ROOT?
	ORA	A	; 0=YES
	JZ	HELP	; RETURN TO HELP
	MVI	A,0	; SET ROOT INDEX
	JMP	GORET

;
;  RETURN TO PREVIOUS HELP LEVEL
;
LRURN:
	LDA	HLPLVL	; ARE WE AT THE LOWEST LEVEL?
	ORA	A	; 0=YES
	JNZ	LRET
	CALL	SAK	; ERROR BELL
	JMP	HELP

;
;  SET NEW HELP LEVEL
;
LRET:
	DCR	A	; DOWN 1 AND FALL THRU TO GORET

;
;  GO TO HELP LEVEL INDEXED IN A
;
GORET:
	STA	HLPLVL	; SET NEW HELP LEVEL
	CALL	COMPTR	; HL=POINTER TO TARGET HELP FILE NAME
	LXI	D,FCB+1	; COPY ELEMENT INTO FCB
	MVI	B,11	; 11 BYTES
	CALL	MOVE
	JMP	PLHFM	; PRINT LOADING MESSAGE AND LOAD

;
;  COMPUTE POINTER TO HELP NAME ENTRY INDEXED BY HELP LEVEL IN A
;
COMPTR:
	MOV	L,A	; VALUE IN HL
	MVI	H,0	; COMPUTE OFFSET AS INDEX*11
	MOV	E,L	; DE=HL
	MOV	D,H
	DAD	H	; *2
	DAD	H	; *4
	DAD	H	; *8
	DAD	D	; *9
	DAD	D	; *10
	DAD	D	; *11
	XCHG		; RESULT IN DE
	LHLD	HLPNSTK	; PT TO BASE OF HELP NAMES
	DAD	D	; ADD IN OFFSET
	RET

;
;  PRINT LEVEL NUMBER
;
PRLEVEL:
	LDA	HLPLVL	; DON'T PRINT LEVEL 0
	ORA	A	; 0?
	JZ	PRFRAME
	CALL	EPRINT
	DB	'Level ',0
	LDA	HLPLVL	; GET NUMBER
	CALL	PAFDC		; PRINT AS DECIMAL
	LDA	FRNUM	; GET FRAME NUMBER
	ORA	A	; SET FLAGS
	MVI	A,'/'	; PREP TO PRINT SLASH
	CNZ	COUT	; PRINT SLASH IF FRAME IS NON-ZERO
PRFRAME:
	LDA	FRNUM	; GET NUMBER
	ORA	A
	MVI	A,' '	; PREP TO PRINT SPACE ON EXIT
	JZ	COUT
	LDA	FRNUM	; GET FRAME NUMBER AGAIN
	CALL	PAFDC	; PRINT AS DECIMAL
	CALL	EPRINT
	DB	': ',0
	RET

;
;  RING ERROR BELL
;
SAK:
	MVI	A,BEL
	JMP	COUT

;
;  BUFFER SECTION
;
HTYPE:
	DS	1	; TYPE OF HELP FILE (IF = IHCHAR, IT IS INDEXED BY USR)
LFRFLAG:
	DS	1	; LIST FRAME ONLY FLAG (FOR PRINT FUNCTION)
TPAEND:
	DS	1	; END PAGE ADDRESS OF TPA
STRTINFO:
	DS	2	; PTR TO START OF CURRENT INFORMATION BLOCK
STRTFRAME:
	DS	2	; PTR TO START OF CURRENT FRAME
SELCHAR:
	DS	1	; SELECTION TABLE OPTION CHAR
FIRSTENTRY:
	DS	2	; PTR TO FIRST ENTRY OF INFORMATION SECTION
LCOUNT:
	DS	1	; LINE COUNT BUFFER
NEXTADR:
	DS	2	; NEXT LOAD ADDRESS
HLPLVL:
	DS	1	; NUMBER OF HELP LEVEL CURRENT NODE IS AT (0=BOTTOM)
FRNUM:
	DS	1	; NUMBER OF CURRENT FRAME
HLPNSTK:
	DS	2	; PTR TO STACK OF HELP FILE NAMES OF EACH LEVEL
HLPBUF:
	DS	2	; PTR TO HELP BUFFER
STACK:
	DS	2	; OPSYS STACK PTR

	END