NimYAML/private/tagLibrary.nim

#            NimYAML - YAML implementation in Nim
#        (c) Copyright 2015 Felix Krause
#
#    See the file "copying.txt", included in this
#    distribution, for details about the copyright.

proc `$`*(id: TagId): string =
  case id
  of yTagQuestionMark: "?"
  of yTagExclamationMark: "!"
  of yTagString: "!!str"
  of yTagSequence: "!!seq"
  of yTagMapping: "!!map"
  of yTagNull: "!!null"
  of yTagBoolean: "!!bool"
  of yTagInteger: "!!int"
  of yTagFloat: "!!float"
  of yTagOrderedMap: "!!omap"
  of yTagPairs: "!!pairs"
  of yTagSet: "!!set"
  of yTagBinary: "!!binary"
  of yTagMerge: "!!merge"
  of yTagTimestamp: "!!timestamp"
  of yTagValue: "!!value"
  of yTagYaml: "!!yaml"
  of yTagNimField: "!nim:field"
  else: "<" & $cast[int](id) & ">"

proc initTagLibrary*(): TagLibrary =
  new(result)
  result.tags = initTable[string, TagId]()
  result.secondaryPrefix = yamlTagRepositoryPrefix
  result.nextCustomTagId = yFirstCustomTagId

proc registerUri*(tagLib: TagLibrary, uri: string): TagId =
  tagLib.tags[uri] = tagLib.nextCustomTagId
  result = tagLib.nextCustomTagId
  tagLib.nextCustomTagId = cast[TagId](cast[int](tagLib.nextCustomTagId) + 1)
    
proc uri*(tagLib: TagLibrary, id: TagId): string =
  for iUri, iId in tagLib.tags.pairs:
    if iId == id: return iUri
  raise newException(KeyError, "Unknown tag id: " & $id)

proc initFailsafeTagLibrary(): TagLibrary =
  result = initTagLibrary()
  result.tags["!"] = yTagExclamationMark
  result.tags["?"] = yTagQuestionMark
  result.tags["tag:yaml.org,2002:str"] = yTagString
  result.tags["tag:yaml.org,2002:seq"] = yTagSequence
  result.tags["tag:yaml.org,2002:map"] = yTagMapping

proc initCoreTagLibrary(): TagLibrary =
  result = initFailsafeTagLibrary()
  result.tags["tag:yaml.org,2002:null"]  = yTagNull
  result.tags["tag:yaml.org,2002:bool"]  = yTagBoolean
  result.tags["tag:yaml.org,2002:int"]   = yTagInteger
  result.tags["tag:yaml.org,2002:float"] = yTagFloat

proc initExtendedTagLibrary(): TagLibrary =
  result = initCoreTagLibrary()
  result.tags["tag:yaml.org,2002:omap"]      = yTagOrderedMap
  result.tags["tag:yaml.org,2002:pairs"]     = yTagPairs
  result.tags["tag:yaml.org,2002:binary"]    = yTagBinary
  result.tags["tag:yaml.org,2002:merge"]     = yTagMerge
  result.tags["tag:yaml.org,2002:timestamp"] = yTagTimestamp
  result.tags["tag:yaml.org,2002:value"]     = yTagValue
  result.tags["tag:yaml.org,2002:yaml"]      = yTagYaml

proc initSerializationTagLibrary(): TagLibrary =
  result = initTagLibrary()
  result.tags["!"] = yTagExclamationMark
  result.tags["?"] = yTagQuestionMark
  result.tags["tag:yaml.org,2002:str"]       = yTagString
  result.tags["tag:yaml.org,2002:null"]      = yTagNull
  result.tags["tag:yaml.org,2002:bool"]      = yTagBoolean
  result.tags["tag:yaml.org,2002:float"]     = yTagFloat
  result.tags["tag:yaml.org,2002:timestamp"] = yTagTimestamp
  result.tags["tag:yaml.org,2002:value"]     = yTagValue
  result.tags["tag:yaml.org,2002:binary"]    = yTagBinary
  result.tags["!nim:field"]                  = yTagNimField
  result.tags["!nim:nil:string"]             = yTagNimNilString
  result.tags["!nim:nil:seq"]                = yTagNimNilSeq