.model small
.486

.data

; -----
;  Constants

CR		equ	13
LF		equ	10
NULL		equ	0

TRUE		equ	1
FALSE		equ	0


; -----
;  Variables for main.

month		dw	?
date		dw	?
year		dw	?

day		dw	?

hdr		db	CR, LF, "CSC218 - Date Formatter"
		db	CR, LF, NULL


; -----
;  Variables for get_date procedure.


pmt_month	db	CR, LF, "Enter Month (1-12): ", NULL
pmt_date	db	CR, LF, "Enter Date (1-31): ", NULL
pmt_year	db	CR, LF, "Enter Year (yyyy): ", NULL

inbuff		db	5
rd		db	?
chrs		db	5 dup (0)

bad_month	db	"Invalid Month, Please Re-Enter"
		db	CR, LF, NULL
bad_date	db	"Invalid Date, Please Re-Enter"
		db	CR, LF, NULL
bad_year	db	"Invalid Year, Please Re-Enter"
		db	CR, LF, NULL

mn_num		dw	?
dt_num		dw	?
yr_num		dw	?
ok_flag		db	?

chk_date	db	0			; n/a
		db	31			; january
		db	29			; february
		db	31			; march
		db	30			; april
		db	31			; may
		db	30			; june
		db	31			; july
		db	31			; august
		db	30			; september
		db	31			; october
		db	30			; november
		db	31			; december


; -----
;  Variables for find_day procedure.

a		dw	?
m		dw	?
y		dw	?


; -----
;  Variables for wrt_date procedure.

dat_str		db	CR, LF, CR, LF, "Date: ", NULL

days		db	"Sunday, ", NULL, "   "
		db	"Monday, ", NULL, "   "
		db	"Tuesday, ", NULL, "  "
		db	"Wednesday, ", NULL
		db	"Thursday, ", NULL, " "
		db	"Friday, ", NULL, "   "
		db	"Saturday, ", NULL, " "
days_size	dw	12

months		db	"January ", NULL, "  "
		db	"February ", NULL, " "
		db	"March ", NULL, "    "
		db	"April ", NULL, "    "
		db	"May ", NULL, "      "
		db	"June ", NULL, "     "
		db	"July ", NULL, "     "
		db	"August ", NULL, "   "
		db	"September ", NULL
		db	"October ", NULL, "  "
		db	"November ", NULL, " "
		db	"December ", NULL, " "
months_size	dw	11

tmp_str		db	10 dup (?)

n_line		db	CR, LF, NULL


; -----
;  Variables for a_to_i and i_to_a procedure.

ten		dw	10

; ------------------------------------------------

.stack

.code

extrn	get_date:near
extrn	find_day:near
extrn	wrt_date:near


; ------------------------------------------------
;  General process:

;	* Prompt user for month, date, and year.
;	   includes performing basic error checking.

;	* Determine the day of week using month/date/year.

;	* Display the day of week, month date, and year
;	   in the required format.


main	proc	far
	mov	ax, @data
	mov	ds, ax

	lea	dx, hdr			; display simple header
	push	dx
	call	prt_string


	push	month
	push	date
	push	year
	call	get_date

	push	month			; calculate day of week
	push	date
	push	year
	push	day
	call	find_day

	push	month			; display formatting date
	push	date
	push	year
	push	day
	call	wrt_date

	mov	ah, 4ch
	int	21h
main	endp


prt_string	proc	near
	push	bp
	mov	bp, sp
	push	ax
	push	bx
	push	dx
	
	mov	bx, word ptr 4[bp]

prt_chr_lp:
	mov	dl, byte ptr [bx]
	cmp	dl, NULL
	je	prt_done

	mov	ah, 02h
	int	21h

	inc	bx
	jmp	prt_chr_lp

prt_done:
	pop	dx
	pop	bx
	pop	ax
	leave
	ret
prt_string	endp

end	main


get_date	proc	near


	push	bp
	mov	bp, sp
	push	ax
	push	dx

	lea	ax
	push	ax
	call	prt_string
	mov	ah, 0ah
	lea	dx, ybuff
	int	21h
	cmp	yrd, 4
	
	pop	dx
	pop	ax
	leave
	ret
	

get_date	endp


find_day	proc	near


	push	bp
	mov	bp, sp

	leave
	ret
	

find_day	endp


wrt_date	proc	near


	push	bp
	mov	bp, sp
	
	leave
	ret
	

wrt_date	endp