Better column support, redefine keys.

- Fix transposition bug (wrap around past G->A)
- Better chord parsing and handling (bass transposed correctly)
- Add column and page break support.

pco_chords.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version       = "0.3.0"
+version       = "0.3.1"
 author        = "Jonathan Bernard"
 description   = "Chord chart formatter compatible with Planning Center Online"
 license       = "MIT"

src/pco_chords.nim

@@ -40,5 +40,5 @@ when isMainModule:
 
  except:
   fatal getCurrentExceptionMsg()
-  debug getCurrentException().getStackTrace
+  debug getCurrentException().getStackTrace()
   quit(QuitFailure)

src/pco_chordspkg/ast.nim

@@ -20,14 +20,16 @@ type
     ccnkColBreak,
     ccnkPageBreak,
     ccnkTransposeKey,
-    ccnkRedefineKey
+    ccnkRedefineKey,
+    ccnkNone
 
   ChordChartPitch* = enum Af, A, Bf, B, C, Df, D, Ef, E, F, Fs, G
 
   ChordChartChord* = object
     original*: string
     rootPitch*: ChordChartPitch
-    flavor*: string
+    flavor*: Option[string]
+    bassPitch*: Option[ChordChartPitch]
 
   ChordChartNode* = ref object
     case kind: ChordChartNodeKind
@@ -39,8 +41,8 @@ type
     of ccnkWord:
       spaceBefore*: bool
       spaceAfter*: bool
-      chord*: ChordChartChord
+      chord*: Option[ChordChartChord]
-      word*: string
+      word*: Option[string]
     of ccnkNote:
       note*: string
       inclInLyrics*: bool
@@ -50,6 +52,7 @@ type
       transposeSteps*: int
     of ccnkRedefineKey:
       newKey*: ChordChartPitch
+    of ccnkNone: discard
 
   ParserContext = ref object
     lines: seq[string]
@@ -58,6 +61,8 @@ type
     curSection: ChordChartNode
     unparsedLineParts: seq[string]
 
+let EMPTY_CHORD_CHART_NODE* = ChordChartNode(kind: ccnkNone)
+
 func `[]`*(ccmd: ChordChartMetadata, key: string): string =
   ccmd.optionalProps[key]
 
@@ -89,7 +94,9 @@ func `$`*(pitch: ChordChartPitch): string =
 func `+`*(pitch: ChordChartPitch, steps: int): ChordChartPitch =
   cast[ChordChartPitch]((ord(pitch) + steps) mod 12)
 
-func `-`*(a, b: ChordChartPitch): int = ord(a) - ord(b)
+func `-`*(a, b: ChordChartPitch): int =
+  result = ord(a) - ord(b)
+  if result < 0: result += 12
 
 func dump*(m: ChordChartMetadata, indent = ""): string =
   return indent & "Metadata\p" & join(m.pairs --> map(indent & "  " & it.key & ": " & it.value), "\p")
@@ -121,11 +128,20 @@ func dump*(ccn: ChordChartNode, indent = ""): string =
   of ccnkWord:
     result = ""
     if ccn.spaceBefore: result &= " "
-    if ccn.chord.flavor.len > 0:
+
-      result &= "[" & $ccn.chord.rootPitch & "_" & ccn.chord.flavor & "]"
+    if ccn.chord.isSome:
-    elif ccn.chord.original.len > 0: result &= "[" & ccn.chord.original & "]"
+      let chord = ccn.chord.get
-    if ccn.chord.original.len > 0: result &= "[" & ccn.chord.original & "]"
+      result &= "["
-    result &= ccn.word
+      if chord.flavor.isNone and chord.bassPitch.isNone:
+        result &= chord.original
+      else:
+        if chord.flavor.isSome:
+          result &= $chord.rootPitch & "_" & chord.flavor.get
+        if chord.bassPitch.isSome:
+          result &= $chord.rootPitch & "/" & $chord.bassPitch.get
+      result &= "]"
+
+    if ccn.word.isSome: result &= ccn.word.get
     if ccn.spaceAfter: result &= " "
 
   of ccnkNote:
@@ -133,6 +149,9 @@ func dump*(ccn: ChordChartNode, indent = ""): string =
     if not ccn.inclInLyrics: result &= "(chords only) "
     result &= ccn.note
 
+  of ccnkNone:
+    result &= indent & "NONE"
+
 func `$`*(cc: ChordChart): string =
   result = "ChordChart\p" &
     dump(cc.metadata, "  ") & "\p" &
@@ -181,31 +200,35 @@ func parsePitch*(ctx: ParserContext, keyValue: string): ChordChartPitch =
   of "f𝄪", "g", "a𝄫": return ChordChartPitch.G
   else: raise ctx.makeError(keyValue.strip & " is not a recognized key.")
 
+# see regexr.com/70nv1
 let CHORD_REGEX =
-  "([[:upper:]][b#♭♮𝄫𝄪]?)" &                #      chord root
+  "([A-G1-7][b#♭♮𝄫𝄪]?)" &               #      chord root
-  "([mM1-9#b♭♮𝄫𝄪Δ+oøoø]|min|maj|aug|dim|sus|6\\/9)*" &  # chord flavor/type
+  "(([mM1-9#b♭♮𝄫𝄪Δ+oøoø][0-9]?|min|maj|aug|dim|sus|6\\/9|\\([1-9#b♭]+\\))*)" &  # chord flavor/type
-  "(\\/[[:upper:]])?"                               # optional bass
+  "(\\/([A-G1-7][b#♭♮𝄫𝄪]?))?"             # optional bass
 let CHORD_PAT = re(CHORD_REGEX)
 
-proc parseChord*(ctx: ParserContext, chordValue: string): ChordChartChord =
+proc parseChord*(
+    ctx: ParserContext, chordValue: string
+  ): Option[ChordChartChord] =
+
   let m = chordValue.match(CHORD_PAT)
-  if m.isNone:
+  if m.isNone: none[ChordChartChord]()
-    return ChordChartChord(
-      original: chordValue,
-      flavor: "")
   else:
     let flavor =
-      if m.get.captures.contains(1): m.get.captures[1]
+      if m.get.captures.contains(1) and m.get.captures[1].len > 0:
-      else: ""
+        some(m.get.captures[1])
+      else: none[string]()
 
-    let bass =
+    let bassPitch =
-      if m.get.captures.contains(2): m.get.captures[2]
+      if m.get.captures.contains(4) and m.get.captures[4].len > 0:
-      else: ""
+        some(ctx.parsePitch(m.get.captures[4]))
+      else: none[ChordChartPitch]()
 
-    return ChordChartChord(
+    return some(ChordChartChord(
       original: chordValue,
       rootPitch: ctx.parsePitch(m.get.captures[0]),
-      flavor: flavor & bass)
+      flavor: flavor,
+      bassPitch: bassPitch))
 
 let METADATA_LINE_PAT = re"^([^:]+):(.*)$"
 let METADATA_END_PAT = re"^-+$"
@@ -289,7 +312,7 @@ proc parseLineParts(ctx: ParserContext, parts: varargs[string]): seq[ChordChartN
         spaceAfter: true, #FIXME
         spaceBefore: true, #FIXME
         chord: ctx.parseChord(m.get.captures[0]),
-        word: m.get.captures[1]))
+        word: some(m.get.captures[1])))
       result &= ctx.parseLineParts(m.get.captures[2])
       continue
 
@@ -300,7 +323,7 @@ proc parseLineParts(ctx: ParserContext, parts: varargs[string]): seq[ChordChartN
         spaceAfter: false, #FIXME
         spaceBefore: false, #FIXME
         chord: ctx.parseChord(m.get.captures[0]),
-        word: ""))
+        word: none[string]()))
       continue
 
     if p.len > 0:
@@ -308,8 +331,8 @@ proc parseLineParts(ctx: ParserContext, parts: varargs[string]): seq[ChordChartN
         kind: ccnkWord,
           spaceAfter: true, #FIXME
           spaceBefore: true, #FIXME
-          chord: ChordChartChord(original: "", flavor: ""),
+          chord: none[ChordChartChord](),
-          word: p))
+          word: some(p)))
 
 proc parseLine(ctx: ParserContext, line: string): ChordChartNode =
   result = ChordChartNode(kind: ccnkLine)
@@ -322,7 +345,7 @@ proc parseLine(ctx: ParserContext, line: string): ChordChartNode =
         spaceAfter: false, #FIXME
         spaceBefore: false, #FIXME
         chord: ctx.parseChord(it.strip),
-        word: ""))
+        word: none[string]()))
 
   else: result.line = ctx.parseLineParts(line.splitWhitespace)
 
@@ -330,7 +353,7 @@ proc readNote(ctx: var ParserContext, endPat: Regex): string =
   let startLineNum = ctx.curLineNum
   result = ""
 
-  while ctx.lines.len > ctx.curLineNum:
+  while ctx.lines.len > ctx.curLineNum and ctx.hasNextLine:
     let line = ctx.nextLine
     let m = line.find(endPat)
     if m.isSome:
@@ -362,7 +385,7 @@ proc parseBody(ctx: var ParserContext): seq[ChordChartNode] =
         # if this is the first character of the line, then let's parse the note
         result.add(ChordChartNode(
           kind: ccnkNote,
-          inclInLyrics: m.get.match .len < 2,
+          inclInLyrics: m.get.match.len < 2,
           note: ctx.readNote(NOTE_END_PAT)))
 
     m = line.match(TRANSPOSE_PAT)
@@ -384,6 +407,16 @@ proc parseBody(ctx: var ParserContext): seq[ChordChartNode] =
         newKey: cast[ChordChartPitch](newKeyInt)))
       continue
 
+    m = line.match(COL_BREAK_PAT)
+    if m.isSome:
+      result.add(ChordChartNode(kind: ccnkColBreak))
+      continue
+
+    m = line.match(PAGE_BREAK_PAT)
+    if m.isSome:
+      result.add(ChordChartNode(kind: ccnkPageBreak))
+      continue
+
     m = line.match(SECTION_LINE_PAT)
     if m.isSome:
       let captures = m.get.captures.toSeq
@@ -397,18 +430,6 @@ proc parseBody(ctx: var ParserContext): seq[ChordChartNode] =
         ctx.curSection.sectionContents &= ctx.parseLineParts(captures[3].get)
       continue
 
-    # FIXME: as implemented, this will not allow column breaks within a section
-    m = line.match(COL_BREAK_PAT)
-    if m.isSome:
-      result.add(ChordChartNode(kind: ccnkColBreak))
-      continue
-
-    # FIXME: as implemented, this will not allow page breaks within a section
-    m = line.match(PAGE_BREAK_PAT)
-    if m.isSome:
-      result.add(ChordChartNode(kind: ccnkPageBreak))
-      continue
-
     else:
       addToCurSection(ctx.parseLine(line))
       continue
@@ -418,6 +439,7 @@ proc parseChordChart*(s: string): ChordChart =
   var parserCtx = ParserContext(
     lines: s.splitLines,
     curLineNum: -1,
+    curSection: EMPTY_CHORD_CHART_NODE,
     unparsedLineParts: @[])
 
   let metadata = parseMetadata(parserCtx)

src/pco_chordspkg/cliconstants.nim

@@ -1,4 +1,4 @@
-const PCO_CHORDS_VERSION* = "0.3.0"
+const PCO_CHORDS_VERSION* = "0.3.1"
 
 const USAGE* = """Usage:
   pco_chords [options]

src/pco_chordspkg/html.nim

@@ -1,4 +1,4 @@
-import std/logging, std/os, std/strutils
+import std/[logging, options, os, strutils]
 import zero_functional
 
 import ./ast
@@ -8,6 +8,7 @@ type
     chart: ChordChart
     currentKey: ChordChartPitch
     sourceKey: ChordChartPitch
+    currentSection: ChordChartNode
 
 const DEFAULT_STYLESHEET* = """
 <style>
@@ -19,9 +20,19 @@ const DEFAULT_STYLESHEET* = """
 
 html { font-family: sans-serif; }
 
+.page-contents {
+  column-width: 336px;
+  column-width: 3.5in;
+}
+
+.column-break { margin-bottom: auto; }
+
 h2 { font-size: 1.25em; }
 
-section { margin-top: 1em; }
+section {
+  break-inside: avoid;
+  padding-top: 1em;
+}
 
 h3 {
   font-size: 1.125rem;
@@ -54,18 +65,30 @@ h3 {
 @media screen {
   body { margin: 1em; }
 }
+
+@media print {
+  .page-contents { column-count: 2; }
+}
 </style>
 """
 
 proc transpose(ctx: FormatContext, chord: ChordChartChord): string =
   let distance = ctx.currentKey - ctx.sourceKey
-  if distance != 0: return $(chord.rootPitch + distance) & chord.flavor
+
-  else: return chord.original
+  if distance != 0:
+    result = $(chord.rootPitch + distance)
+    if chord.flavor.isSome: result &= chord.flavor.get
+    if chord.bassPitch.isSome: result &= "/" & $(chord.bassPitch.get + distance)
+    #debug "transposed " & $ctx.sourceKey & " -> " & $ctx.currentKey &
+    #  " (distance " & $distance & ")\p\tchord: " & $chord & " to " & result
+
+  else: result = chord.original
 
 proc toHtml(ctx: var FormatContext, node: ChordChartNode, indent: string): string =
   result = ""
   case node.kind
   of ccnkSection:
+    ctx.currentSection = node
     result &= indent & "<section>\p" &
       indent & "  " & "<h3>" & node.sectionName & "</h3>\p"
 
@@ -75,6 +98,7 @@ proc toHtml(ctx: var FormatContext, node: ChordChartNode, indent: string): strin
     result &= contents.join("\p")
 
     result &= indent & "</section>"
+    ctx.currentSection = EMPTY_CHORD_CHART_NODE
 
   of ccnkLine:
     result &= indent & "<div class=line>\p"
@@ -87,11 +111,11 @@ proc toHtml(ctx: var FormatContext, node: ChordChartNode, indent: string): strin
     if node.spaceAfter: result&=" space-after"
     result &= "'>"
 
-    if node.chord.original.len > 0:
+    if node.chord.isSome:
-      result &= "<span class=chord>" & ctx.transpose(node.chord) & "</span>"
+      result &= "<span class=chord>" & ctx.transpose(node.chord.get) & "</span>"
 
     result &= "<span class=lyric>"
-    if node.word.len > 0: result &= node.word
+    if node.word.isSome: result &= node.word.get
     else: result &= "&nbsp;"
     result &= "</span>"
 
@@ -100,16 +124,32 @@ proc toHtml(ctx: var FormatContext, node: ChordChartNode, indent: string): strin
   of ccnkNote:
     result &= indent & "<div class=note>" & node.note & "</div>"
 
-  of ccnkColBreak: discard #FIXME
+  of ccnkColBreak:
-  of ccnkPageBreak: discard #FIXME
+    result &= "<div class=column-break />"
+
+  of ccnkPageBreak:
+    result &= "</div><div class=page-contents>"
 
   of ccnkTransposeKey:
     ctx.currentKey = ctx.currentKey + node.transposeSteps
+    let headingVal = indent & "<h4 class=note>Key Change: " & $ctx.currentKey & "</h4>"
+    if ctx.currentSection.kind == ccnkNone: result &= headingVal
+    else:
+      result &= "</section><section>" & headingVal & "</section><section>"
 
   of ccnkRedefineKey:
-    ctx.sourceKey = ctx.currentKey + node.transposeSteps
+    let oldKey = ctx.sourceKey
+    ctx.sourceKey = node.newKey
     ctx.currentKey = ctx.sourceKey
 
+    if oldKey != ctx.currentKey:
+      let headingVal = indent & "<h4 class=note>Key Change: " & $ctx.currentKey & "</h4>"
+      if ctx.currentSection.kind == ccnkNone: result &= headingVal
+      else:
+        result &= "</section><section>" & headingVal & "</section><section>"
+
+  of ccnkNone: discard
+
 proc toHtml*(
     cc: ChordChart,
     stylesheets = @[DEFAULT_STYLESHEET],
@@ -118,7 +158,8 @@ proc toHtml*(
   var ctx = FormatContext(
     chart: cc,
     currentKey: cc.metadata.key,
-    sourceKey: cc.metadata.key)
+    sourceKey: cc.metadata.key,
+    currentSection: EMPTY_CHORD_CHART_NODE)
 
   result = """<!doctype html>
 <html>
@@ -142,10 +183,18 @@ proc toHtml*(
   # Title
   result &= indent & "<h1>" & cc.metadata.title & "</h1>\p"
 
-  result &= indent & "<h2>Key: " & $cc.metadata.key
+  var metadataPieces = @["Key: " & $cc.metadata.key]
-  if cc.metadata.contains("bpm"): result &= " " & cc.metadata["bpm"] & "bpm"
+  if cc.metadata.contains("time signature"):
-  result &= "</h2>\p"
+    metadataPieces.add(cc.metadata["time signature"])
+  if cc.metadata.contains("bpm"):
+    metadataPieces.add(cc.metadata["bpm"] & "bpm")
+  if cc.metadata.contains("tempo"):
+    metadataPieces.add(cc.metadata["tempo"])
 
+  result &= indent & "<h2>" & metadataPieces.join(" | ") & "</h2>\p"
+
+  result &= "<div class=page-contents>"
   result &= join(cc.nodes --> map(ctx.toHtml(it, indent & "  ")), "\p")
+  result &= "</div>"
 
   result &= "  </body>\p</html>"