; Kira Swab
; Assembly Assignment #4
; March 28, 2001

; This editor program allows the user to control the color of text on the screen

.model small
.stack 100h
.data

goinghere      db  "going here",0
mousestring    db  "no mouse", 0
menu           db "0  Black |1  Blue  |2 Green  |3  Cyan  "
               db  "|4  Red   |5 Magenta|6  Brown |7 White  |",0
rowpix         dw     ?
colpix         dw     ?
char           db     20 dup (?)
attribute      db     ?
diffcolor      db     ?
c_row          db     ?
c_col          db     ?

GreenOnWhite   = 72h
CursorLocation = 0300h
MenuLocation   = 0000h
WhiteOnBlack   = 07h
BlackOnBlack   = 00h
BlueOnBlack    = 01h
GreenOnBlack   = 02h
CyanOnBlack    = 03h
RedOnBlack     = 04h
MagentaOnBlack = 05h
BrownOnBlack   = 06h
slash          db ?

.code
extern Clrscr:proc, Crlf:proc, Gotoxy:proc
extern Scroll:proc, Writestring:proc

main proc
  mov ax,               @data
  mov ds,               ax

SetColor:
  mov  ah,   0               ;set vid mode
  mov  al,   83h             ;mode 3 w/o clrscr
  int  10h

MenuSpot:
  call Clrscr                             ;clear screen
  mov  cx,    0               ;get left r/c
  mov  dh,    0               ;get right row
  mov  dl,   79               ;get right col
  mov  bh,  GreenOnWhite          ;sets vid. attr.
  call Scroll                 ;scroll whitescreen
  mov  dx,  MenuLocation      ;sets dx w/ r/c
  call Gotoxy                 ;moves cursor to r/c
  mov  dx,      offset menu   ;offset string
  call Writestring            ;writes menu in g/w
  jmp  Window
  mov  c_row, 3
  mov  c_col, 0

Window:
  mov  ch,  c_row
  mov  cl,  c_col
  mov  dx,  184eh             ;sets r/c for window
  mov  bh,  WhiteOnBlack      ;sets attributes
  mov  attribute, bh
  mov  dx, 0300h
  jmp MouseSetup
  jmp  Cursor

MouseSetup:
  push ax
  push bx
  push cx
  push dx
  mov  ax, 0000h
  int  33h
  cmp  ax, 0
  jne DisplayMouse
  mov dx, offset mousestring
  call writestring

DisplayMouse:
  mov ax, 0001h
  int 33h
  pop dx
  pop cx
  pop bx
  pop ax
  jmp Cursor

Cursor:
  call Gotoxy
  jmp WriteChar

WriteChar:
  mov  ah,    8           ;gets char
  int  21h
  mov  char,    al       ;saves char
  jmp  CheckChar

Attributes:
  mov ah, 8
  int 21h

OutputChar:
  mov  char, al
  mov  ah,    9          ;function code

  mov  bl, attribute     ;attribute
  mov  bh,    0          ;vid pg.
  mov  cx,    1          ;repetitions
  int  10h
  jmp  GetCursor

CheckChar:
  cmp  char,    7eh     ;hex for ~
  je   EndSpot
  cmp  char,    08h     ;hex for bspace
  je   GetCursor
  cmp  char,    5ch     ;hex for bslash
  mov  slash, al
  je   BackSlash
  jmp  OutputChar

BackSlash:
  mov  ah, 8
  int  21h
  mov  diffcolor, al
  cmp  diffcolor, "0"
  je   BlackSlash
  cmp  diffcolor, "1"
  je   BlueSlash
  cmp  diffcolor, "2"
  je   GreenSlash
  cmp  diffcolor, "3"
  je   CyanSlash
  cmp  diffcolor, "4"
  je   RedSlash
  cmp  diffcolor, "5"
  je   MagentaSlash
  cmp  diffcolor, "6"
  je   BrownSlash
  cmp  diffcolor, "7"
  je   WhiteSlash
  jmp  Attributes

BlackSlash:
  mov  attribute,  BlackOnBlack
  jmp  SetColorChar

BlueSlash:
  mov  attribute,  BlueOnBlack
  jmp  SetColorChar

GreenSlash:
  mov  attribute,  GreenOnBlack
  jmp  SetColorChar

CyanSlash:
  mov  attribute,  CyanOnBlack
  jmp  SetColorChar

RedSlash:
  mov  attribute,  RedOnBlack
  jmp  SetColorChar

MagentaSlash:
  mov  attribute,  MagentaOnBlack
  jmp  SetColorChar

BrownSlash:
  mov  attribute,  BrownOnBlack
  jmp  SetColorChar

WhiteSlash:
  mov  attribute,  WhiteOnBlack
  jmp  SetColorChar

SetColorChar:
  jmp  WriteChar

MoveBack:
  mov  ah,              2
  mov  dh,  c_row
  sub  c_col, 1
  mov  dl,  c_col
  mov  bh,              0
  int  10h
  jmp  WriteChar

GetCursor:
  mov  ah,    3        ;get cursor pos.
  mov  bh,    0        ;vid pg.
  int  10h             ;call BIOS
  mov  c_row, dh       ;save cur. row
  mov  c_col, dl       ;save cur. col

  cmp  char, 08h
  je   MoveBack
;  jmp  AdvanceCursor
  jmp  CheckRow

CheckRow:
  cmp c_col,    79
  je  CarriageReturn
  jne AdvanceCursor

CarriageReturn:
  cmp  c_row,   24
  je   PageScroll
  call Crlf
  jmp  WriteChar

PageScroll:
  push ax
  push bx
  push cx
  push dx

  mov  ah,     6      ;scroll wind. up
  mov  ch,     3
  mov  cl,     0
  mov  dh,     24
  mov  dl,     79
  mov  al,     1
  mov  bh,     attribute
  int  10h
  pop  dx
  pop  cx
  pop  bx
  pop  ax
  mov  dh,     24
  mov  dl,      0
  jmp Cursor

AdvanceCursor:
  mov  ah,   2        ;set cursor pos.
  mov  dh,   c_row
  add  c_col, 1
  mov  dl,   c_col
  mov  bh,   0
  int  10h
  jmp  Cursor

EndSpot:
  mov  ah, 2
  mov  dh, 23
  mov  dl, 0
  mov  bh, 0
  int 10h
  mov  ax, 4c00h
  int  21h

main endp

end  main