CBDOS directory output tweaks

src/dos_m65/utils/util_dir_filesize.s

@@ -2,8 +2,96 @@
 ; Adapt the file size for displaying in a directory list
 
 
-util_dir_filesize:
+util_dir_filesize_bytes: ; preserves .X
 
-	; XXX provide implementation
+	; Convert file size in bytes (32-bit value) to blocks, afterwards
+	; continue processing in 'util_dir_filesize_blocks'
 
+	; XXX temporary - calculate size in 254-byte blocks
+
+	lda PAR_FSIZE_BYTES+1
+	sta PAR_FSIZE_BLOCKS+0
+	lda PAR_FSIZE_BYTES+2
+	sta PAR_FSIZE_BLOCKS+1
+
+	; FALLTROUGH
+
+util_dir_filesize_blocks: ; preserves .X
+
+	; Take file size in blocks (16-bit value), clip to max 9999,
+	; return in .Y the amount of spaces needed for indentation
+	
+	lda PAR_FSIZE_BLOCKS+1
+	cmp #>9999
+	beq @cmp_9999_p2
+	bcs util_dir_filesize_max
+	bcc @size_ok
+
+@cmp_9999_p2:
+
+	lda PAR_FSIZE_BLOCKS+0
+	cmp #<9999
+	bcs util_dir_filesize_max
+
+@size_ok:
+	
+	lda PAR_FSIZE_BLOCKS+1
+	beq @size_123
+
+@size_34:  ; file size is 256 or above (3 or 4 digits)
+
+	cmp #>1000
+	beq @cmp_1000_p2
+	bcs util_dir_filesize_4
+	bra util_dir_filesize_3
+
+@cmp_1000_p2:
+
+	lda PAR_FSIZE_BLOCKS+0
+	cmp #<1000
+	bcs util_dir_filesize_4
+	bra util_dir_filesize_3
+
+@size_123: ; file size is 255 or below (1, 2, or 3 digits)
+
+	lda PAR_FSIZE_BLOCKS+0
+	cmp #10
+	bcs util_dir_filesize_23
+
+	; FALLTROUGH
+
+util_dir_filesize_1:  ; file size needs 1 digit
+
+	ldy #$03
+	rts
+
+util_dir_filesize_23: ; file size needs 2 or 3 digits, size in .A
+
+	cmp #100
+	bcs util_dir_filesize_3
+
+	; FALLTROUGH
+
+util_dir_filesize_2:  ; file size needs 2 digits
+
+	ldy #$02
+	rts
+
+util_dir_filesize_3: ; file size needs 3 digits
+
+	ldy #$01
+	rts
+
+util_dir_filesize_max:
+
+	lda #<9999
+	sta PAR_FSIZE_BLOCKS+0
+	lda #>9999
+	sta PAR_FSIZE_BLOCKS+1
+
+	; FALLTROUGH
+
+util_dir_filesize_4: ; file size needs 4 digits
+
+	ldy #$00
 	rts