DOSSEG
.MODEL TINY
.STACK 100h
.DATA
inputFile DB 'input.txt',0
outputFile DB 'output.txt',0
error DB 'Error unable to open file.',0
text DB 2000 DUP('$')
buffer DB '2', '$'
.CODE
.386

file_write macro str
 mov ah, 40h
 push bx
 mov bx, di
 mov cx, 1
 lea si, buffer
 mov [si], str
 mov dx, si
 int 21h
 pop bx
endm

start:
mov ax, @Data
mov ds, ax
mov es, ax

; opening file
mov ah, 3Dh
mov al, 0
lea dx, inputFile
int 21h
jc error_no_file

mov si, ax

; reading
lea dx, text

reading_file:
 mov ah, 3Fh
 mov bx, si
 mov cx, 1
 int 21h
 inc dx
 cmp ax, 1
 je reading_file

; closing inputfile
 mov ah, 3Eh
 mov bx, si
 int 21h

; creating new file
mov al, 1h
mov ah, 3Ch
mov cx, 0
lea dx, outputFile
int 21h
mov di, ax

; main part
mov cx, 0
mov bx, OFFSET text
mov dx, bx

iter:
 cmp cx, 0
 je met
 add bx, 1
 met:
  mov cx, 1
 mov al, [bx]
 cmp al, 40h
 jbe nextword
 cmp al, 4Dh
 jbe print
 cmp al, 60h
 jbe nextword
 cmp al, 6Dh
 jbe print
 jmp nextword

print:
 mov ah, 2
 mov dl, al
 int 21h
 file_write al
 cmp al, 20h
 jz iter

znaki:
 cmp [bx + 1], ah
 jz printspace
 add ah, 1
 cmp ah, 30h
 jbe znaki
 add bx, 1
 mov al, [bx]
 cmp al, 13
 jz cancel
 jmp print

nextword:
 cmp al, 20h
 jz iter
 add bx, 1
 mov al, [bx]
 cmp al, 13
 jz cancel
 jmp nextword

printspace:
 mov ah, 2
 mov dl, 20h
 int 21h
 file_write 20h
 jmp iter

cancel:
 mov ah, 2
 mov dl, 10
 int 21h
; closing outputFile
 mov ah, 3Eh
 mov bx, di
 int 21h
 mov ah, 4ch
 int 21h

error_no_file:
 lea dx, error
 mov ah, 9h
 int 21h
 mov ah, 4ch
 int 21h

end start