//------------------------------------------------------------------------
//                        Decimal Output Library
//
// Purpose: Display BYTE and WORD values as decimal numbers
//
// Functions:
//   lib_decout_decoutb({BYTE value})  - Print BYTE (0-255) as decimal
//   lib_decout_decoutw({WORD value})  - Print WORD (0-65535) as decimal
//
// Dependencies: cbmiolib.c65 (for lib_cbmio_print)
// No ZP usage required
//
// Algorithm: Repeated subtraction per decimal place
//   - decoutb: max 7 iterations (2+5+0 for 255)
//   - decoutw: max 19 iterations (6+5+5+3+0 for 65535)
//   No division needed, self-contained, ~5-6x faster than general div
//------------------------------------------------------------------------

#IFNDEF __LIB_DECOUT
#DEFINE __LIB_DECOUT = 1

GOTO lib_decout_skip

//-----------------------------------------------------------
// Output string buffer (5 digits + null terminator = 6 bytes)
//-----------------------------------------------------------
ASM
lib_decout_buf
  !8 0,0,0,0,0,0
ENDASM

//-----------------------------------------------------------
// Pointer for building the output string
// Non-ZP: compiler uses self-modifying code for POKE
//-----------------------------------------------------------
WORD lib_decout_ptr

//-----------------------------------------------------------
// decoutb - Display BYTE (0-255) as decimal with leading zero
//           suppression
//-----------------------------------------------------------
FUNC lib_decout_decoutb ( {BYTE value} )
  BYTE digit
  BYTE leading
  BYTE ch

  POINTER lib_decout_ptr TO lib_decout_buf
  leading = 0

  // Hundreds place
  digit = 0
  WHILE value >= 100
    value = value - 100
    digit++
  WEND
  IF digit != 0
    ch = digit + $30
    POKE lib_decout_ptr , ch
    INC lib_decout_ptr
    leading = 1
  ENDIF

  // Tens place
  digit = 0
  WHILE value >= 10
    value = value - 10
    digit++
  WEND
  IF digit != 0
    ch = digit + $30
    POKE lib_decout_ptr , ch
    INC lib_decout_ptr
    leading = 1
  ENDIF
  IF leading != 0
    IF digit == 0
      ch = digit + $30
      POKE lib_decout_ptr , ch
      INC lib_decout_ptr
    ENDIF
  ENDIF

  // Ones place
  ch = value + $30
  POKE lib_decout_ptr , ch
  INC lib_decout_ptr
  POKE lib_decout_ptr , 0

  CALL lib_cbmio_print ( @lib_decout_buf )
FEND

//-----------------------------------------------------------
// decoutw - Display WORD (0-65535) as decimal with leading
//           zero suppression
//-----------------------------------------------------------
FUNC lib_decout_decoutw ( {WORD value} )
  BYTE digit
  BYTE leading
  BYTE ch

  POINTER lib_decout_ptr TO lib_decout_buf
  leading = 0

  // Ten-thousands place
  digit = 0
  WHILE value >= 10000
    value = value - 10000
    digit++
  WEND
  IF digit != 0
    ch = digit + $30
    POKE lib_decout_ptr , ch
    INC lib_decout_ptr
    leading = 1
  ENDIF

  // Thousands place
  digit = 0
  WHILE value >= 1000
    value = value - 1000
    digit++
  WEND
  IF digit != 0
    ch = digit + $30
    POKE lib_decout_ptr , ch
    INC lib_decout_ptr
    leading = 1
  ENDIF
  IF leading != 0
    IF digit == 0
      ch = digit + $30
      POKE lib_decout_ptr , ch
      INC lib_decout_ptr
    ENDIF
  ENDIF

  // Hundreds place
  digit = 0
  WHILE value >= 100
    value = value - 100
    digit++
  WEND
  IF digit != 0
    ch = digit + $30
    POKE lib_decout_ptr , ch
    INC lib_decout_ptr
    leading = 1
  ENDIF
  IF leading != 0
    IF digit == 0
      ch = digit + $30
      POKE lib_decout_ptr , ch
      INC lib_decout_ptr
    ENDIF
  ENDIF

  // Tens place
  digit = 0
  WHILE value >= 10
    value = value - 10
    digit++
  WEND
  IF digit != 0
    ch = digit + $30
    POKE lib_decout_ptr , ch
    INC lib_decout_ptr
    leading = 1
  ENDIF
  IF leading != 0
    IF digit == 0
      ch = digit + $30
      POKE lib_decout_ptr , ch
      INC lib_decout_ptr
    ENDIF
  ENDIF

  // Ones place
  ch = value + $30
  POKE lib_decout_ptr , ch
  INC lib_decout_ptr
  POKE lib_decout_ptr , 0

  CALL lib_cbmio_print ( @lib_decout_buf )
FEND


LABEL lib_decout_skip
#IFEND