;license:MIT
;(c) 2018-9 by 4am
;
; generic key/value text parser
;
; Public functions:
; - ParseKeyValueList
; - IncAndGetChar
;

;------------------------------------------------------------------------------
; ParseKeyValueList
; parse buffer with KEY=VALUE lines of a text file into an okvs
; keys and values limited to 127 characters, which should be enough for anyone
; if '=' is missing, key is kept and value is a 0-length string
; blank lines are ignored
; '#' character at beginning of line is a comment, entire line is ignored
; '[' character at beginning of line exits the parser
;
; in:    stack contains 5 bytes of parameters:
;          +1 [word] handle to storage space for okvs
;          +3 [word] handle to buffer containing contents of text file
;          +5 [byte] max length for okvs records (or 0)
; out:   all registers and flags clobbered
;        $1F00..$1FFF clobbered
;        $00/$01 clobbered
;        $02/$03 clobbered
;        $04/$05 has the address of the next available byte after the okvs
;        $FE/$FF clobbered
;------------------------------------------------------------------------------
ParseKeyValueList
         +PARAMS_ON_STACK 5

         +LDPARAM 1                  ; not LDPARAMPTR, SetKeyPtr requires A/Y!
         +ST16 @store2
         jsr   SetKeyPtr
         ldy   #5
         lda   (PARAM),y
         sta   @maxLength

         ldy   #$00                  ; index into ($FE) pointing to current character
@newkey  ldx   #$00                  ; X = index into current key
         stx   gValLen               ; initialize value length (in case this line has no value)
         beq   @emptyline            ; always branches
@skipLine                            ; skip to CR
         jsr   IncAndGetChar
         cmp   #$0A                  ; CR
         bne   @skipLine
@emptyline
         jsr   IncAndGetChar
         cmp   #$0A                  ; CR in first position (blank line) -> no key
         beq   @emptyline
         cmp   #$23                  ; '#' starts a comment -> no key, skip to CR
         beq   @skipLine
         cmp   #$5B                  ; '[' ends the parsing
         beq   .parseKeyValueDone
         bne   @appendToKey
@gatherKey
         jsr   IncAndGetChar
         cmp   #$0A                  ; CR -> finalize key, no value
         beq   @finalizeKey
         cmp   #$3D                  ; '=' -> finalize key, start gathering value
         beq   @finalizeKey
@appendToKey
         sta   gKey,x
         inx
         bpl   @gatherKey
@finalizeKey
         stx   gKeyLen
         cmp   #$0A
         beq   @storeInOKVS
         ldx   #$00                  ; now X = index into the current value
@gatherValue
         jsr   IncAndGetChar
         cmp   #$0A                  ; CR -> finalize value
         beq   @finalizeValue
         sta   gVal,x
         inx
         bpl   @gatherValue
@finalizeValue
         stx   gValLen
@storeInOKVS
         tya
         pha                         ; okvs functions clobber everything but we need Y
         jsr   okvs_append
@store2  !word $FDFD                 ; SMC
         !word gKeyLen
         !word gValLen
@maxLength
         !byte $FD                   ; SMC
         pla
         tay
         clc
         bcc   @newkey               ; always branches

;------------------------------------------------------------------------------
; SetKeyPtr
;
; in:    PARAM set
; out:   okvs initialised
;        ($FE) -> buffer
;------------------------------------------------------------------------------
SetKeyPtr
         jsr   okvs_init             ; reset key/value store

         +LDPARAMPTR 3, $FE

         ldy   #0
         lda   ($FE),y
         tax
         bne   +
         iny
         lda   ($FE),y
         sta   $FF
         dec   $FF
+        dex
         stx   $FE
         rts

;------------------------------------------------------------------------------
; IncAndGetChar
;
; in:    Y = index into ($FE)
;        ($FE) -> buffer
; out:   A contains next byte from buffer
;        Y incremented
;        $FF possibly incremented
;------------------------------------------------------------------------------
IncAndGetChar
         iny
         bne   +
         inc   $FF
+        lda   ($FE),y
         cmp   #$0D                  ; CR - hide it
         beq   IncAndGetChar
.parseKeyValueDone
         rts

;------------------------------------------------------------------------------
; okvs_append
;
; in:    stack contains 7 bytes of parameters:
;          +1 [word] handle to storage space
;          +3 [word] address of key
;          +5 [word] address of value
;          +7 [byte] maximum length of value (or 0 to fit)
; out:   (new record count is not returned because no one cares)
;        all registers clobbered
;        $00/$01 clobbered
;        $02/$03 clobbered
;        $04/$05 has the address of the next available byte after the new record
;        $08/$09 clobbered
;------------------------------------------------------------------------------
okvs_append
         +PARAMS_ON_STACK 7
         jsr   GetStoreAddress
                                     ; PTR -> store
                                     ; Y = 0
         lda   (PTR),y               ; A = number of keys in store
         sta   WINDEX
         iny
         lda   (PTR), y
         sta   WINDEX+1
         inc   WINDEX
         bne   +
         inc   WINDEX+1
+
         dey
         lda   WINDEX
         sta   (PTR),y               ; increment number of keys
         lda   WINDEX+1
         iny
         sta   (PTR),y
         iny
         lda   (PTR),y               ; get address of next free space
         tax
         iny
         lda   (PTR),y
         sta   PTR+1
         sta   SAVE+1
         stx   PTR
         stx   SAVE
                                     ; PTR -> new record
                                     ; SAVE -> new record
         jsr   incptr
                                     ; PTR -> space for new key
         +LDPARAMPTR 3, SRC          ; SRC -> new key to copy
         ldy   #0
         lda   (SRC),y
         tay
         tax
-        lda   (SRC),y               ; copy new key
         sta   (PTR),y
         dey
         cpy   #$FF
         bne   -

         ;;sec
         txa
         adc   PTR                   ; update PTR to byte after copied key
         sta   PTR
         bcc   +
         inc   PTR+1
+                                    ; PTR -> space for new value
         +LDPARAMPTR 5, SRC          ; SRC -> new value to copy
         iny ;;ldy   #7
         lda   (PARAM),y             ; get max length of value
         tax
         bne   +
         tay
         lda   (SRC),y               ; no max, use actual length instead
         tax
+        inx
         tay
-        lda   (SRC),y
         sta   (PTR),y
         dey
         cpy   #$FF
         bne   -

         txa
         clc
         adc   PTR
         tax
         lda   PTR+1
         adc   #0
         pha
+        jsr   GetStoreAddress
                                     ; PTR -> store
         pla
         ldy   #3
         sta   (PTR),y               ; update next-free-space pointer in head
         dey
         txa
         sta   (PTR),y
         sec
         sbc   SAVE
         ldy   #0
         sta   (SAVE),y              ; set record length
         rts