; ==================================================
; TYPE.COM
;
; Disassembled by Romych,  2026-03-01
; ==================================================

    DEVICE  NOSLOT64K

    INCLUDE "equates.inc"

    OUTPUT  TYPE.COM

    MODULE  TYPE

    ORG     0x0100

; ---------------------------------------------------
; Entry point
; ---------------------------------------------------
start:
    LD        HL, t_start
    LD        SP, HL
    LD        DE, 0x0
    PUSH      DE
    JP        (HL)

    DB "roDOS TYPE FILE Utility(C) IRIMS, Moscow 1985"

t_start:
    CALL t_check_version
    ; unsupported bdos call
    LD   C, 49
    LD   DE, t_scb_1
    CALL jp_bdos_enter
    DEC  A
    DEC  A
    LD   (t_scb_mm), A

    ; At start command line params here
    LD   HL, p_cmd_line_len
    LD   (t_buff_addr), HL
    LD   A, (HL)
    LD   (cmd_par_len), A

    ; skip spaces before first parameter
.skip_sp_0:
    CALL t_get_cmdl_char
    JP   C, t_handle_error
    CP   ASCII_SP
    JP   Z, .skip_sp_0

    ; get filename
.get_next_ch:
    CALL t_get_cmdl_char
    JP   C, t_open_file
    CP   ASCII_SP
    JP   NZ, .get_next_ch

    ; get
.skip_sp_1:
    CALL t_get_cmdl_char
    JP   C, t_open_file
    CP   ASCII_SP
    JP   Z, .skip_sp_1
    CP   'P'
    JP   Z, t_param_P
    CP   'D'
    JP   NZ, t_param_no_PD
    LD   A, 1
    JP   t_param_cmn

t_param_no_PD:
    CP   'C'
    JP   NZ, t_param_no_D
    LD   A, 2
    JP   t_param_cmn

t_param_no_D:
    CP   'F'
    JP   NZ, t_param_unknown
    LD   A, 3

t_param_cmn:
    LD   (cmd_switch), A

.skip_sp_2:
    CALL t_get_cmdl_char
    JP   C, t_open_file
    CP   ASCII_SP
    JP   Z, .skip_sp_2

t_param_P:
    CP   'P'
    JP   NZ, t_param_unknown
    LD   A, 0xff
    LD   (flag1), A
    CALL get_numbr
    JP   C, t_open_file
    LD   A, L
    OR   A
    JP   Z, t_open_file
    LD   (t_scb_mm), A

t_open_file:
    LD   C, 15
    LD   DE, fcb1
    CALL jp_bdos_enter
    CP   0xff
    JP   Z, t_handle_error
    LD   HL, tpa
    LD   (t_buff_addr), HL

t_dump_part:
    LD   A, (t_scb_mm)
    LD   (cmd_par_len), A

print_next_byte:
    ; get next byte, return if error
    CALL t_get_nxt_byte
    RET  C
    ; return if end of text marker
    CP   ASCII_SUB
    RET  Z

    ; print character
    LD   (t_cut_byte), A
    LD   E, A
    CALL t_print

    LD   A, (t_cut_byte)
    CP   ASCII_LF
    JP   NZ, print_next_byte
    ; LF
    LD   A, (flag0)
    OR   A
    JP   Z, lo_ctr_0

    ; wait until keyboard key pressed
wait_for_key:
    CALL t_get_key_wo_echo
    OR   A
    JP   Z, wait_for_key

    ; check for Ctrl+C - interrupt
    CP   CTRL_C
    JP   Z, t_is_ctrl_c

    ; Space - fro continue
    CP   ASCII_SP
    JP   Z, print_next_byte

    CP   CTRL_P
    JP   NZ, is_no_ctrl_p

    ; Access the System Control Block (Unsupported!)
    ; get value at offset
    LD   C, 49
    LD   DE, t_scb_2
    CALL jp_bdos_enter
    XOR  0xff
    LD   (t_scb_3+2), A
    ; set new value an offset
    LD   C, 49
    LD   DE, t_scb_3
    CALL jp_bdos_enter
    ; and wait for next key
    JP   wait_for_key

is_no_ctrl_p:
    ; Return key
    CP   ASCII_CR
    JP   NZ, t_is_no_cr
    ; update hi counter
    LD   A, 0xff
    LD   (flag1), A
    ; zero to low counter
    XOR  A
    LD   (flag0), A
    ; and dump next part
    JP   t_dump_part

t_is_no_cr:
    ; other key - zero counters
    XOR  A
    LD   (flag0), A
    LD   (flag1), A
    JP   print_next_byte

lo_ctr_0:
    CALL t_get_key_wo_echo
    OR   A
    JP   Z, no_key_pressd

lo_ctr_set_ff:
    LD   A, 0xff
    LD   (flag0), A
    JP   wait_for_key

no_key_pressd:
    LD   A, (flag1)
    OR   A
    JP   Z, print_next_byte
    
    LD   A, (cmd_par_len)
    DEC  A
    LD   (cmd_par_len), A
    JP   NZ, print_next_byte
    JP   lo_ctr_set_ff

; ---------------------------------------------------
;
; ---------------------------------------------------
t_check_version
    LD   C, 12
    CALL jp_bdos_enter
    CP   0x26
    JP   C, t_ver_unsupported
    CP   0x30
    JP   NC, t_ver_unsupported
    RET

t_param_unknown:
    LD   E, 0x0
    JP   t_calc_msg_offset

t_handle_error:
    LD   E, 0x1
    JP   t_calc_msg_offset

t_is_ctrl_c:
    LD   E, 0x2

t_calc_msg_offset:
    LD   HL, t_message_tab
    LD   D, 0x0
    ADD  HL, DE
    ADD  HL, DE
    LD   E, (HL)
    INC  HL
    LD   D, (HL)
    ; C_WRITESTR - Output string
    LD   C, 9
    JP   jp_bdos_enter

; ---------------------------------------------------
; Print character
; Inp: E - charater to print
; ---------------------------------------------------
t_print:
    LD   A, (cmd_switch)
    OR   A
    JP   Z, t_con_output                        ; D
    CP   1
    JP   Z, t_get_key_echo                      ; C

    LD   A, E
    AND  0x7f                                   ; limit to 0..127 codes
    ; check for printable
    CP   ASCII_SP
    JP   NC, t_con_output
    CP   ASCII_CR
    JP   Z, t_con_output
    CP   ASCII_LF
    JP   Z, t_con_output
    CP   ASCII_TAB
    JP   Z, t_con_output
    CP   ASCII_SO                               ; ^N 0xe
    JP   Z, t_con_output
    CP   ASCII_SI                               ; ^O 0xf
    JP   Z, t_con_output
    LD   A, (cmd_switch)
    ; if param='F', and unprintable char, do not print
    CP   3
    RET  Z

    ; replace unprintable with '^'
    PUSH DE
    LD   E, '^'
    CALL t_con_output
    POP  DE

    ;
    LD   A, E
    OR   0x40
    LD   E, A
    JP   t_con_output

; --------------------------------------------------
; Return keyboard key if pressed
; Out: A - key code, 0 - no key
; --------------------------------------------------
t_get_key_wo_echo:
    LD   E, 0xff

t_get_key_echo:
    LD   C, 6
    JP   jp_bdos_enter

t_con_output:
    LD   C, 2
    JP   jp_bdos_enter

t_ver_unsupported:
    HALT

; ---------------------------------------------------
; Get next character from command line
; Out: A - character
;      CF is set if EOL
;      ZF is set if A=0
; ---------------------------------------------------
t_get_cmdl_char:
    ; there are still characters in the cmd line?
    LD   A, (cmd_par_len)
    OR   A
    JP   NZ, t_get_next_cmdc                        ; jump if not eol
    CCF
    RET

t_get_next_cmdc:
    ; decrement characters count
    DEC  A
    LD   (cmd_par_len), A
    ; get next character to A
    LD   HL, (t_buff_addr)
    INC  HL
    LD   A, (HL)
    ; update pointer
    LD   (t_buff_addr), HL
    OR   A
    RET

; ---------------------------------------------------
;
; ---------------------------------------------------
get_numbr:
    LD   C, 10
    CALL t_get_cmdl_char
    LD   HL, 0x0

t_do_nxt_lettr:
    JP   NC, t_has_a_lettr
    OR   A
    RET

t_has_a_lettr:
    CP   ASCII_SP
    RET  Z
    CALL t_is_digits
    RET  C
    CP   C
    CCF
    RET  C
    LD   D, H
    LD   E, L
    LD   L, A
    LD   H, 0
    LD   A, C
    CALL t_next_hl_de
    PUSH HL
    CALL t_get_cmdl_char
    POP  HL
    JP   t_do_nxt_lettr

; ---------------------------------------------------
;
; ---------------------------------------------------
t_is_digits:
    SBC  A, '0'
    RET  C
    CP   10
    JP   C, .digit
    SBC  A, 7
    CP   10
    RET  C
.digit:
    CP   16
    CCF
    RET

; ---------------------------------------------------
;
; ---------------------------------------------------
t_next_hl_de:
    OR   A
    RET  Z
    RRA
    JP   NC, .a0_is_0
    ADD  HL, DE
.a0_is_0:
    EX   DE, HL
    ADD  HL, HL
    EX   DE, HL
    JP   t_next_hl_de

; ---------------------------------------------------
;
; ---------------------------------------------------
t_get_nxt_byte:
    LD   HL, (t_buff_addr)
    LD   DE, 0xff00
    ADD  HL, DE
    LD   A, H
    OR   L
    CALL Z, t_read_next_128
    RET  C
    LD   HL, (t_buff_addr)
    LD   A, (HL)
    INC  HL
    LD   (t_buff_addr), HL
    RET

; ---------------------------------------------------
;
; ---------------------------------------------------
t_read_next_128:
    LD   DE, dma_buffer
    ;(F_DMAOFF) - Set DMA address
    LD   C, 26
    CALL jp_bdos_enter
    LD   DE, fcb1
    ;(F_READ) - read next record
    LD   C, 20
    CALL jp_bdos_enter
    RRA
    LD   HL, dma_buffer
    LD   (t_buff_addr), HL
    RET

; ---------------------------------------------------
; Variables
; ---------------------------------------------------

flag0:
    db   0x00
flag1:
    db   0x00

; Cmd line switch D-1,  C-2, F-3
cmd_switch:
    db   0x00

t_scb_mm:
    db   0x00

t_cut_byte:
    db   0x00

cmd_par_len:
    db   0x00

t_buff_addr:
    dw   0x0000

t_scb_1:
    db   0x1c   ; offset
    db   0      ; read byte at offset onto a, and word into hl
    db   0, 0

t_scb_2:
    db   0x38   ; offset
    db   0,     ; read byte at offset onto a, and word into hl
    db   0 ,0

t_scb_3:
    db   0x38   ; offset
    db   0xff   ; save next byte to SCB+offset
    db   0 , 0

;t_val_scb1
;   dw   0x0000

t_message_tab:
    dw   msg_err_cmdline
    dw   msg_no_file
    dw   msg_interrupted

msg_err_cmdline:
    db   "o{ibka komandnoj stroki. ispolxzujte\r\n"
    db   "TYPE UFN SWITCH   \t ili\r\n"
    db   "TYPE UFN SWITCH P \t ili\r\n"
    db   "TYPE UFN SWITCH P#\r\n\t"
    db   "s perekl`~atelem SWITCH:\tNO   D   C   F\r\n"
    db   "$"

msg_no_file:
    db   "net fajla$"


msg_interrupted:
    db   "\r\nTYPE prerwana$"

filler1:
    ds 88, 0x1A
filler2:
    ds 1024+start-filler2, 0xe5
    ENDMODULE