JSONDecoder {.importc: "json_decoder", header: "pd_api.h".} = object
  decodeError* {.importc: "decodeError".}: proc (decoder: ptr JSONDecoder;
      error: cstring; linenum: cint) {.cdecl.} ## the following functions are each optional
  willDecodeSublist* {.importc: "willDecodeSublist".}: proc (
      decoder: ptr JSONDecoder; name: cstring; type: JSONValueType) {.cdecl.}
  shouldDecodeTableValueForKey* {.importc: "shouldDecodeTableValueForKey".}: proc (
      decoder: ptr JSONDecoder; key: cstring): cint {.cdecl.}
  didDecodeTableValue* {.importc: "didDecodeTableValue".}: proc (
      decoder: ptr JSONDecoder; key: cstring; value: JSONValue) {.cdecl.}
  shouldDecodeArrayValueAtIndex* {.importc: "shouldDecodeArrayValueAtIndex".}: proc (
      decoder: ptr JSONDecoder; pos: cint): cint {.cdecl.}
  didDecodeArrayValue* {.importc: "didDecodeArrayValue".}: proc (
      decoder: ptr JSONDecoder; pos: cint; value: JSONValue) {.cdecl.} ## if pos==0, this was a bare value at the root of the file
  didDecodeSublist* {.importc: "didDecodeSublist".}: proc (
      decoder: ptr JSONDecoder; name: cstring; type: JSONValueType): pointer {.
      cdecl.}
  userdata* {.importc: "userdata".}: pointer
  returnString* {.importc: "returnString".}: cint ## when set, the decoder skips parsing and returns the current subtree as a string
  path* {.importc: "path".}: cstring ## updated during parsing, reflects current position in tree

JSONEncoder {.importc: "json_encoder", header: "pd_api.h".} = object
  writeStringFunc* {.importc: "writeStringFunc".}: ptr WriteFunc
  userdata* {.importc: "userdata".}: pointer
  pretty* {.importc: "pretty".}: cint
  startedTable* {.importc: "startedTable".}: cint
  startedArray* {.importc: "startedArray".}: cint
  depth* {.importc: "depth".}: cint
  startArray* {.importc: "startArray".}: proc (encoder: ptr JSONEncoder) {.cdecl.}
  addArrayMember* {.importc: "addArrayMember".}: proc (encoder: ptr JSONEncoder) {.
      cdecl.}
  endArray* {.importc: "endArray".}: proc (encoder: ptr JSONEncoder) {.cdecl.}
  startTable* {.importc: "startTable".}: proc (encoder: ptr JSONEncoder) {.cdecl.}
  addTableMember* {.importc: "addTableMember".}: proc (encoder: ptr JSONEncoder;
      name: cstring; len: cint) {.cdecl.}
  endTable* {.importc: "endTable".}: proc (encoder: ptr JSONEncoder) {.cdecl.}
  writeNull* {.importc: "writeNull".}: proc (encoder: ptr JSONEncoder) {.cdecl.}
  writeFalse* {.importc: "writeFalse".}: proc (encoder: ptr JSONEncoder) {.cdecl.}
  writeTrue* {.importc: "writeTrue".}: proc (encoder: ptr JSONEncoder) {.cdecl.}
  writeInt* {.importc: "writeInt".}: proc (encoder: ptr JSONEncoder; num: cint) {.
      cdecl.}
  writeDouble* {.importc: "writeDouble".}: proc (encoder: ptr JSONEncoder;
      num: cdouble) {.cdecl.}
  writeString* {.importc: "writeString".}: proc (encoder: ptr JSONEncoder;
      str: cstring; len: cint) {.cdecl.}

JSONReader {.importc: "json_reader", header: "pd_api.h".} = object
  read* {.importc: "read".}: proc (userdata: pointer; buf: ptr uint8;
                                   bufsize: cint): cint {.cdecl.} ## fill buffer, return bytes written or -1 on end of data
  userdata* {.importc: "userdata".}: pointer ## passed back to the read function above

JSONValue {.importc: "json_value", header: "pd_api.h".} = object
  data* {.importc: "data".}: JSONValueUnion

JSONValueType {.size: 1.} = enum
  kJSONNull, kJSONTrue, kJSONFalse, kJSONInteger, kJSONFloat, kJSONString,
  kJSONArray, kJSONTable

JSONValueUnion {.importc: "json_value::no_name", header: "pd_api.h", bycopy,
                 union.} = object
  intval* {.importc: "intval".}: cint
  floatval* {.importc: "floatval".}: cfloat
  stringval* {.importc: "stringval".}: cstring
  arrayval* {.importc: "arrayval".}: pointer
  tableval* {.importc: "tableval".}: pointer

PlaydateJSON {.importc: "const struct playdate_json", header: "pd_api.h".} = object

WriteFunc = proc (userdata: pointer; str: cstring; len: cint) {.cdecl.}