server_parser:

; Commands are always 3 numbers and followed by a space
; If a server decides it needs multiline output,
; first lines will have a dash instead of space after numbers,
; thus they are simply ignored in this simple command parser.

        cmp     dword[buf_cmd], "150 "
        je      data_loop

        cmp     dword[buf_cmd], "220 "
        je      welcome

;        cmp     dword[buf_cmd], "226 "
;        je      transfer_ok

        cmp     dword[buf_cmd], "227 "
        je      pasv_ok

        cmp     dword[buf_cmd], "230 "
        je      login_ok

;        cmp     dword[buf_cmd], "250"
;        je      op_ok

        cmp     dword[buf_cmd], "331 "
        je      pass

;        cmp     dword[buf_cmd], "421 "
;        je      timeout

        cmp     dword[buf_cmd], "503 "         ; login first
        je      welcome

        cmp     dword[buf_cmd], "530 "         ; password incorrect
        mov     [use_params], 0
        je      welcome

        cmp     dword[buf_cmd], "550 "
        je      close_datacon

        cmp     byte[buf_cmd+3], "-"
        je      wait_for_servercommand
        jmp     wait_for_usercommand


welcome:

        mov     [status], STATUS_CONNECTED
        jmp     wait_for_usercommand


pass:

        mov     [status], STATUS_NEEDPASSWORD
        jmp     wait_for_usercommand


login_ok:

        mov     [status], STATUS_LOGGED_IN
        cmp     [use_params], 0
        je      wait_for_usercommand

        cmp     [param_path+4], 0
        je      wait_for_usercommand
        ; copy path to buf_cmd and execute CWD
        mov     edi, buf_cmd
        mov     esi, param_path
  @@:
        lodsb
        stosb
        cmp     byte[esi-1], 0
        jne     @b
        jmp     cmd_cwd

pasv_ok:

        sub     ecx, 4
        jb      .fail
        mov     al, "("
        mov     edi, buf_cmd + 4
        repne   scasb

        mcall   socket, AF_INET4, SOCK_STREAM, 0
        cmp     eax, -1
        jne     @f
        mov     eax, str_err_socket
        jmp     error
    @@: mov     [datasocket], eax

        mov     esi, edi
        call    ascii_dec
        mov     byte[sockaddr2.ip+0], bl
        call    ascii_dec
        mov     byte[sockaddr2.ip+1], bl
        call    ascii_dec
        mov     byte[sockaddr2.ip+2], bl
        call    ascii_dec
        mov     byte[sockaddr2.ip+3], bl

        call    ascii_dec
        mov     byte[sockaddr2.port+0], bl
        call    ascii_dec
        mov     byte[sockaddr2.port+1], bl

        invoke  con_write_asciiz, str_open
        mcall   connect, [datasocket], sockaddr2, 18
        cmp     eax, -1
        jne     @f
        mov     eax, str_err_connect
        jmp     error
    @@: jmp     wait_for_servercommand

  .fail:
        invoke  con_write_asciiz, str_unknown
        jmp     wait_for_servercommand


data_loop:

        invoke  con_write_asciiz, str_dot

        cmp     [operation], OPERATION_STOR
        je      .stor

; we are receiving data
        mcall   recv, [datasocket], buf_buffer2, BUFFERSIZE, 0
        test    ebx, ebx
        jnz     .done
        mov     byte[buf_buffer2 + eax], 0

        cmp     [operation], OPERATION_RETR
        je      .retr

        cmp     [operation], OPERATION_RDIR
        je      .rdir
        
; not retreiving, just print to console
        invoke  con_write_asciiz, buf_buffer2
        jmp     data_loop

; retreiving, save to file
  .retr:
        mov     [filestruct.ptr], buf_buffer2
        mov     [filestruct.size], eax
        push    eax
        mcall   70, filestruct
        pop     eax
        add     [filestruct.offset], eax
        jmp     data_loop

; storing, send all data
  .stor:
        mcall   70, filestruct
        cmp     eax, 6          ; end of file
        je      .last_call
        test    eax, eax        ; error
;        jne     .fileerror
        add     [filestruct.offset], ebx
        mov     esi, ebx
        mcall   send, [datasocket], buf_buffer2, , 0
        jmp     .stor

  .last_call:
        mov     esi, ebx
        mcall   send, [datasocket], buf_buffer2, , 0

  .done:
        invoke  con_write_asciiz, str_close
        mcall   close, [datasocket]
        mov     [operation], OPERATION_NONE
        jmp     wait_for_servercommand

  .rdir:
        ; alloc/realloc memory block to store filenames
        mov     ecx, eax                        ; eax is size of buffer received
        inc     ecx
        add     ecx, [size_fname]               ; added old size to form new required size
        mcall   68, 20, , [ptr_fname]           ; realloc
        test    eax, eax
        je      error_heap
        mov     [ptr_fname], eax                ; eax contains the new block now
        mov     [ptr_queue], eax

        ; copy filenames into fname buffer
        mov     esi, buf_buffer2
        mov     edi, eax
        add     edi, [size_fname]
  .copy_buf:
        lodsb
        cmp     al, 13                          ; ignore any carriage return character
        je      .copy_buf
        stosb
        cmp     al, 10                          ; linefeed marks end of filename
        je      @f
        inc     [queued]
  @@:
        test    al, al                          ; 0 marks end of buffer
        jne     .copy_buf

        ; All received filenames have been copied, calculate new size of fname buffer
        dec     edi                             ; dont count the trailing 0 byte
        sub     edi, [ptr_fname]
        mov     [size_fname], edi       
        jmp     data_loop


close_datacon:
        cmp     [operation], OPERATION_NONE
        je      wait_for_usercommand
        invoke  con_write_asciiz, str_close
        mcall   close, [datasocket]
        jmp     wait_for_usercommand


ascii_dec:

        xor     ebx, ebx
        mov     cl, 4                   ; max length is 3 digits + 1 separator
  .loop:
        lodsb
        sub     al, '0'
        jb      .done
        cmp     al, 9
        ja      .done
        lea     ebx, [ebx*4+ebx]        ; ebx *5
        shl     ebx, 1                  ; ebx *2
        add     bl, al
        dec     cl
        jnz     .loop

  .done:
        ret