Key of C should use flats for accidentals.

- Non-diatonic pitches are supported using Nashville numbers (#5).
- When using Nashville numbers chord variants with non-diatonic roots
  are now recognized (e.g. b7)
- Pitch rendering is now aware of key centers. For example, F# is F#
  rendered as F# when in the key of G but Gb when in the key of Ab.

pco_chords.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version       = "0.5.0"
+version       = "0.5.2"
 author        = "Jonathan Bernard"
 description   = "Chord chart formatter compatible with Planning Center Online"
 license       = "MIT"

src/pco_chordspkg/ast.nim

@@ -23,7 +23,7 @@ type
     ccnkRedefineKey,
     ccnkNone
 
-  ChordChartPitch* = enum Af, A, Bf, B, C, Df, D, Ef, E, F, Fs, G
+  ChordChartPitch* = enum Af, A, Bf, B, C, Df, D, Ef, E, F, Gf, G
 
   ChordChartChord* = object
     original*: Option[string]
@@ -77,20 +77,60 @@ iterator pairs*(ccmd: ChordChartMetadata): tuple[key, value: string] =
 
 func kind*(ccn: ChordChartNode): ChordChartNodeKind = ccn.kind
 
-func `$`*(pitch: ChordChartPitch): string =
-  case pitch
-  of Af: "Ab"
-  of A: "A"
-  of Bf: "Bb"
-  of B: "B"
-  of C: "C"
-  of Df: "Db"
-  of D: "D"
-  of Ef: "Eb"
-  of E: "E"
-  of F: "F"
-  of Fs: "F#"
-  of G: "G"
+func `$`(pitch: ChordChartPitch): string =
+  ["A♭", "A", "B♭", "B", "C", "D♭", "D", "E♭", "E", "F", "G♭", "G"][ord(pitch)]
+
+func renderPitchInKey*(
+    pitch: ChordChartPitch,
+    key: ChordChartPitch,
+    useSharps: Option[bool] = none[bool]()): string =
+
+  var scaleNames: array[(ord(high(ChordChartPitch)) + 1), string]
+  if useSharps.isNone:
+    scaleNames = case key
+    of A, B, D, E, G:
+      ["G#", "A", "A#", "B", "C", "C#", "D", "D#", "E", "F", "F#", "G"]
+    of Af, Bf, C, Df, Ef, F:
+      ["A♭", "A", "B♭", "B", "C", "D♭", "D", "E♭", "E", "F", "G♭", "G"]
+    of Gf:
+      ["A♭", "A", "B♭", "C♭", "C", "D♭", "D", "E♭", "E", "F", "G♭", "G"]
+
+  elif useSharps.isSome and useSharps.get:
+    scaleNames = case key
+    of A, B, C, D, E, G:
+      ["G#", "A", "A#", "B", "C", "C#", "D", "D#", "E", "F", "F#", "G"]
+    of Af:
+      ["G#", "A", "A#", "B", "B#", "C#", "D", "D#", "E", "E#", "F#", "F𝄪"]
+    of Bf:
+      ["G#", "G𝄪", "A#", "B", "B#", "C#", "C𝄪", "D#", "E", "E#", "F#", "F𝄪"]
+    of Df:
+      ["G#", "A", "A#", "B", "B#", "C#", "D", "D#", "E", "E#", "F#", "G"]
+    of Ef:
+      ["G#", "A", "A#", "B", "B#", "C#", "C𝄪", "D#", "E", "E#", "F#", "F𝄪"]
+    of Gf:
+      ["G#", "A", "A#", "B", "C", "C#", "D", "D#", "E", "E#", "F#", "G"]
+    of F:
+      ["G#", "G𝄪", "A#", "B", "B#", "C#", "C𝄪", "D#", "D𝄪", "E#", "F#", "F𝄪"]
+
+  else: # useSharps.isSome and not useSharps.get
+    scaleNames = case key
+    of C, Af, Bf, Df, Ef, F:
+      ["A♭", "A", "B♭", "B", "C", "D♭", "D", "E♭", "E", "F", "G♭", "G"]
+    of A:
+      ["A♭", "B𝄫", "B♭", "C♭", "C", "D♭", "E𝄫", "E♭", "F♭", "F", "G♭", "G"]
+    of B:
+      ["A♭", "A", "B♭", "C♭", "C", "D♭", "D", "E♭", "F♭", "F", "G♭", "G"]
+    of D:
+      ["A♭", "B𝄫", "B♭", "C♭", "C", "D♭", "E𝄫", "E♭", "F♭", "F", "G♭", "A𝄫"]
+    of E:
+      ["A♭", "B𝄫", "B♭", "C♭", "C", "D♭", "D", "E♭", "F♭", "F", "G♭", "G"]
+    of G:
+      ["A♭", "B𝄫", "B♭", "C♭", "D𝄫", "D♭", "E𝄫", "E♭", "F♭", "F", "G♭", "A𝄫"]
+    of Gf:
+      ["A♭", "A", "B♭", "C♭", "C", "D♭", "D", "E♭", "E", "F", "G♭", "G"]
+
+
+  return scaleNames[ord(pitch)]
 
 func `+`*(pitch: ChordChartPitch, steps: int): ChordChartPitch =
   cast[ChordChartPitch]((ord(pitch) + steps) mod 12)
@@ -193,29 +233,34 @@ proc parsePitch*(ctx: ParserContext, keyValue: string): ChordChartPitch =
   of "gs", "gis", "g#", "ab", "a♭", "af", "aes": return ChordChartPitch.Af
   of "g𝄪", "a", "a♮", "b𝄫": return ChordChartPitch.A
   of "as", "ais", "a#", "bf", "bb", "b♭", "bes", "c𝄫": return ChordChartPitch.Bf
-  of "a𝄪", "b", "cb", "ces", "cf": return ChordChartPitch.B
+  of "a𝄪", "b", "c♭", "cb", "ces", "cf": return ChordChartPitch.B
   of "bs", "bis", "b#", "c", "d𝄫": return ChordChartPitch.C
-  of "b𝄪", "cs", "cis", "c#", "df", "db", "des": return ChordChartPitch.Df
+  of "b𝄪", "cs", "cis", "c#", "d♭", "df", "db", "des": return ChordChartPitch.Df
   of "c𝄪", "d", "e𝄫": return ChordChartPitch.D
-  of "ds", "dis", "d#", "ef", "eb", "ees", "f𝄫": return ChordChartPitch.Ef
-  of "d𝄪", "e", "fes", "ff": return ChordChartPitch.E
+  of "ds", "dis", "d#", "ef", "e♭", "eb", "ees", "f𝄫": return ChordChartPitch.Ef
+  of "d𝄪", "e", "f♭", "fes", "ff": return ChordChartPitch.E
   of "es", "eis", "e#", "f", "g𝄫": return ChordChartPitch.F
-  of "e𝄪", "fs", "fis", "f#", "gf", "gb", "ges": return ChordChartPitch.Fs
+  of "e𝄪", "fs", "fis", "f#", "g♭", "gf", "gb", "ges": return ChordChartPitch.Gf
   of "f𝄪", "g", "a𝄫": return ChordChartPitch.G
-  of "1": return ctx.curKeyCenter
-  of "2": return ctx.curKeyCenter + 2
-  of "3": return ctx.curKeyCenter + 4
-  of "4": return ctx.curKeyCenter + 5
-  of "5": return ctx.curKeyCenter + 7
-  of "6": return ctx.curKeyCenter + 9
-  of "7": return ctx.curKeyCenter + 11
+  of "#7", "1", "𝄫2": return ctx.curKeyCenter
+  of "𝄪7", "#1", "b2", "♭2": return ctx.curKeyCenter + 1
+  of "𝄪1", "2", "𝄫3": return ctx.curKeyCenter + 2
+  of "#2", "b3", "♭3", "𝄫4": return ctx.curKeyCenter + 3
+  of "𝄪2", "3", "b4", "♭4": return ctx.curKeyCenter + 4
+  of "#3", "4", "𝄫5": return ctx.curKeyCenter + 5
+  of "𝄪3", "#4", "b5", "♭5": return ctx.curKeyCenter + 6
+  of "𝄪4", "5", "𝄫6": return ctx.curKeyCenter + 7
+  of "#5", "b6", "♭6": return ctx.curKeyCenter + 8
+  of "𝄪5", "6", "𝄫7": return ctx.curKeyCenter + 9
+  of "#6", "b7", "♭7", "𝄫1": return ctx.curKeyCenter + 10
+  of "7", "b1", "♭1": return ctx.curKeyCenter + 11
   else: raise ctx.makeError(keyValue.strip & " is not a recognized key.")
 
 # see regexr.com/70nv1
 let CHORD_REGEX =
-  "([A-G1-7][b#♭♮𝄫𝄪]?)" &               #      chord root
+  "([b#♭♮𝄫𝄪]?[A-G1-7][b#♭♮𝄫𝄪]?)" &               #      chord root
   "(([mM1-9#b♭♮𝄫𝄪Δ+oøoø][0-9]?|min|maj|aug|dim|sus|6\\/9|\\([1-9#b♭]+\\))*)" &  # chord flavor/type
-  "(\\/([A-G1-7][b#♭♮𝄫𝄪]?))?"             # optional bass
+  "(\\/([b#♭♮𝄫𝄪]?[A-G1-7][b#♭♮𝄫𝄪]?))?"             # optional bass
 let CHORD_PAT = re(CHORD_REGEX)
 
 proc parseChord*(
@@ -413,7 +458,7 @@ proc parseBody(ctx: var ParserContext): seq[ChordChartNode] =
     m = line.match(REDEFINE_KEY_PAT)
     if m.isSome:
       let newKeyInt = (
-          cast[int](ctx.curKeyCenter) +
+          ord(ctx.curKeyCenter) +
           parseInt(m.get.captures[0])
         ) mod 12
 

src/pco_chordspkg/cliconstants.nim

@@ -1,4 +1,4 @@
-const PCO_CHORDS_VERSION* = "0.5.0"
+const PCO_CHORDS_VERSION* = "0.5.2"
 
 const USAGE* = """Usage:
   pco_chords [options]

src/pco_chordspkg/html.nim

@@ -113,9 +113,9 @@ func scaleDegree(root: ChordChartPitch, p: ChordChartPitch): string =
   else: raise newException(Exception, "Impossible")
 
 func format(ctx: FormatContext, chord: ChordChartChord, useNumber = false): string =
-  if not useNumber and chord.original.isSome: return chord.original.get
+  ##if not useNumber and chord.original.isSome: return chord.original.get
 
-  elif useNumber:
+  if useNumber:
     result = "<span class=root>" &
       ctx.currentKey.scaleDegree(chord.rootPitch) & "</span>"
 
@@ -127,11 +127,15 @@ func format(ctx: FormatContext, chord: ChordChartChord, useNumber = false): stri
         ctx.currentKey.scaleDegree(chord.bassPitch.get) & "</span>"
 
   else:
-    result = $chord.rootPitch
-    if chord.flavor.isSome: result &= chord.flavor.get
-    if chord.bassPitch.isSome: result &= "/" & $chord.bassPitch.get
-    #debug "transposed " & $ctx.sourceKey & " -> " & $ctx.currentKey &
-    #  " (distance " & $distance & ")\p\tchord: " & $chord & " to " & result
+    result = "<span class=root>" &
+      renderPitchInKey(chord.rootPitch, ctx.currentKey) & "</span>"
+
+    if chord.flavor.isSome:
+      result &= "<span class=flavor>" & chord.flavor.get & "</span>"
+
+    if chord.bassPitch.isSome:
+      result &= "<span class=bass>/" &
+        renderPitchInKey(chord.bassPitch.get, ctx.currentKey) & "</span>"
 
 proc transpose(ctx: FormatContext, chord: ChordChartChord): ChordChartChord =
   result = chord