; The OS/K Team licenses this file to you under the MIT license.
; See the LICENSE file in the project root for more information.

#define N 11

.handle_DIR:
    push ebp
    mov ebp, esp

    push nx0, nx1
    push nx2, nx3

    nul nx0     ; no. of files found
    nul nx1     ; no. of directories found
    nul nx2     ; total amount of bytes found

    call print, .dirmsg

.dir_first:
    mov eax, Sys.FindFirst
    mov ax0, .dir_buf
    mov ax1, FNAME_MAX
    trap 0

    jmp .dir_list

.dir_next:
    mov eax, Sys.FindNext
    mov ax0, .dir_buf
    mov ax1, FNAME_MAX
    trap 0

.dir_list:
    jeaxz .dir_end

    mov nx3, ecx ; file size
    add nx2, ecx

    ; directory?
    bnz edx, .dir_is_dir

    ; found a file
    inc nx0

    ; separate extension from file name
    mov ecx, FNAME_MAX
    mov esi, .dir_buf
    mov edi, esi
    scasb esi, '.'

    ; print file name
    sub ax1, esi, edi
    dec ax1
    call nprint, edi

    ; calculate where to put extension
    sub edi, esi, .dir_buf
    dec edi

.dir_ext_pad:
    ; print at least N non-space characters before extension
    blte N, edi, .dir_print_ext
    prn ' '
    inc edi
    jmp .dir_ext_pad

.dir_print_ext:
    prn ' '
    ; here we print at least 4 characters excluding '.'
    mov ecx, 4

    bne b[esi], '.', .dir_print_ext.1
    inc esi

.dir_print_ext.1:
    bzr b[esi], .dir_print_ext.2

    ; print and decrease ecx, unless it's already 0
    prn b[esi]
    inc esi
    jecxz .dir_print_ext.1

    dec ecx
    jmp .dir_print_ext.1

.dir_print_ext.2:
    ; did we print at least 4 bytes?
    jecxz .dir_print_bytes    ; yes, carry on

.dir_pe2.l:
    prn ' '
    loop .dir_pe2.l

.dir_print_bytes:
    ; print file size in bytes
    prn ' '
    prn ' '
    prn ' '

    shr eax, nx3, 10
    and nx3, 1023

    push nx3, eax
    call printf, .dir_bytesstr
    add esp, 16

.dir_prepare_next:
    ; go find next entry
    prn 10
    jmp .dir_next

.dir_end:
    shr eax, nx2, 10
    shr edx, eax, 10
    and eax, 1023
    and nx2, 1023

    push nx2, eax, edx
    call printf, .dir_endstr0
    add esp, 24

    push nx1, nx0
    call printf, .dir_endstr1
    add esp, 16

    pop nx3, nx2
    pop nx1, nx0

    leave
    jmp .print_prompt

    ; special case: direcory
.dir_is_dir:
    inc nx1

    ; use printf instead of print
    ; because it returns the # of
    ; printed characters
    call printf, .dir_buf

    blte N, eax, .dir_no_pad
    sub ecx, N, eax
    dec ecx

.dir.l:
    prn ' '
    loop .dir.l

.dir_no_pad:
    call print, .dir_ext

    jmp .dir_print_bytes

.dir_buf = [FNAME_MAX]
.dir_ext = " <DIR> "
.dir_endstr0 = "             total %dMB + %dKB + %dB\n"
.dir_endstr1 = "             found %d file(s), %d dir(s)\n"
.dirmsg = "Directory of C:\\\n\n"

.dir_bytesstr = "%d kilobytes + %d bytes"
; .dir_bytesstr = "%dMB + %dKB + %dB" # too soon

#undef N