1 files changed, 288 insertions, 0 deletions
diff --git a/packages/docutils/rstast.nim b/packages/docutils/rstast.nim
new file mode 100644
index 000000000..23233fd39
--- /dev/null
+++ b/packages/docutils/rstast.nim
@@ -0,0 +1,288 @@
+#
+#
+#            Nimrod's Runtime Library
+#        (c) Copyright 2012 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+## This module implements an AST for the `reStructuredText`:idx parser.
+
+import strutils
+
+type
+  TRstNodeKind* = enum        ## the possible node kinds of an PRstNode
+    rnInner,                  # an inner node or a root
+    rnHeadline,               # a headline
+    rnOverline,               # an over- and underlined headline
+    rnTransition,             # a transition (the ------------- <hr> thingie)
+    rnParagraph,              # a paragraph
+    rnBulletList,             # a bullet list
+    rnBulletItem,             # a bullet item
+    rnEnumList,               # an enumerated list
+    rnEnumItem,               # an enumerated item
+    rnDefList,                # a definition list
+    rnDefItem,                # an item of a definition list consisting of ...
+    rnDefName,                # ... a name part ...
+    rnDefBody,                # ... and a body part ...
+    rnFieldList,              # a field list
+    rnField,                  # a field item
+    rnFieldName,              # consisting of a field name ...
+    rnFieldBody,              # ... and a field body
+    rnOptionList, rnOptionListItem, rnOptionGroup, rnOption, rnOptionString, 
+    rnOptionArgument, rnDescription, rnLiteralBlock, rnQuotedLiteralBlock,
+    rnLineBlock,              # the | thingie
+    rnLineBlockItem,          # sons of the | thing
+    rnBlockQuote,             # text just indented
+    rnTable, rnGridTable, rnTableRow, rnTableHeaderCell, rnTableDataCell,
+    rnLabel,                  # used for footnotes and other things
+    rnFootnote,               # a footnote
+    rnCitation,               # similar to footnote
+    rnStandaloneHyperlink, rnHyperlink, rnRef, rnDirective, # a directive
+    rnDirArg, rnRaw, rnTitle, rnContents, rnImage, rnFigure, rnCodeBlock,
+    rnRawHtml, rnRawLatex,
+    rnContainer,              # ``container`` directive
+    rnIndex,                  # index directve:
+                              # .. index::
+                              #   key
+                              #     * `file#id <file#id>`_
+                              #     * `file#id <file#id>'_
+    rnSubstitutionDef,        # a definition of a substitution
+    rnGeneralRole,            # Inline markup:
+    rnSub, rnSup, rnIdx, 
+    rnEmphasis,               # "*"
+    rnStrongEmphasis,         # "**"
+    rnTripleEmphasis,         # "***"
+    rnInterpretedText,        # "`"
+    rnInlineLiteral,          # "``"
+    rnSubstitutionReferences, # "|"
+    rnSmiley,                 # some smiley
+    rnLeaf                    # a leaf; the node's text field contains the
+                              # leaf val
+
+
+  PRSTNode* = ref TRstNode    ## an RST node
+  TRstNodeSeq* = seq[PRstNode]
+  TRSTNode* {.acyclic, final.} = object ## an RST node's description
+    kind*: TRstNodeKind       ## the node's kind
+    text*: string             ## valid for leafs in the AST; and the title of
+                              ## the document or the section
+    level*: int               ## valid for some node kinds
+    sons*: TRstNodeSeq        ## the node's sons
+
+proc len*(n: PRstNode): int = 
+  result = len(n.sons)
+
+proc newRstNode*(kind: TRstNodeKind): PRstNode = 
+  new(result)
+  result.sons = @[]
+  result.kind = kind
+
+proc newRstNode*(kind: TRstNodeKind, s: string): PRstNode = 
+  result = newRstNode(kind)
+  result.text = s
+
+proc lastSon*(n: PRstNode): PRstNode = 
+  result = n.sons[len(n.sons)-1]
+
+proc add*(father, son: PRstNode) =
+  add(father.sons, son)
+
+proc addIfNotNil*(father, son: PRstNode) = 
+  if son != nil: add(father, son)
+
+
+type
+  TRenderContext {.pure.} = object
+    indent: int
+    verbatim: int
+
+proc renderRstToRst(d: var TRenderContext, n: PRstNode, result: var string)
+
+proc renderRstSons(d: var TRenderContext, n: PRstNode, result: var string) = 
+  for i in countup(0, len(n) - 1): 
+    renderRstToRst(d, n.sons[i], result)
+  
+proc renderRstToRst(d: var TRenderContext, n: PRstNode, result: var string) =
+  # this is needed for the index generation; it may also be useful for
+  # debugging, but most code is already debugged...
+  const 
+    lvlToChar: array[0..8, char] = ['!', '=', '-', '~', '`', '<', '*', '|', '+']
+  if n == nil: return
+  var ind = repeatChar(d.indent)
+  case n.kind
+  of rnInner: 
+    renderRstSons(d, n, result)
+  of rnHeadline:
+    result.add("\n")
+    result.add(ind)
+    
+    let oldLen = result.len
+    renderRstSons(d, n, result)
+    let HeadlineLen = result.len - oldLen
+
+    result.add("\n")
+    result.add(ind)
+    result.add repeatChar(HeadlineLen, lvlToChar[n.level])
+  of rnOverline:
+    result.add("\n")
+    result.add(ind)
+
+    var headline = ""
+    renderRstSons(d, n, headline)
+    
+    let lvl = repeatChar(headline.Len - d.indent, lvlToChar[n.level])
+    result.add(lvl)
+    result.add("\n")
+    result.add(headline)
+    
+    result.add("\n")
+    result.add(ind)
+    result.add(lvl)
+  of rnTransition: 
+    result.add("\n\n")
+    result.add(ind)
+    result.add repeatChar(78-d.indent, '-')
+    result.add("\n\n")
+  of rnParagraph:
+    result.add("\n\n")
+    result.add(ind)
+    renderRstSons(d, n, result)
+  of rnBulletItem: 
+    inc(d.indent, 2)
+    var tmp = ""
+    renderRstSons(d, n, tmp)
+    if tmp.len > 0: 
+      result.add("\n")
+      result.add(ind)
+      result.add("* ")
+      result.add(tmp)
+    dec(d.indent, 2)
+  of rnEnumItem:
+    inc(d.indent, 4)
+    var tmp = ""
+    renderRstSons(d, n, tmp)
+    if tmp.len > 0: 
+      result.add("\n")
+      result.add(ind)
+      result.add("(#) ")
+      result.add(tmp)
+    dec(d.indent, 4)
+  of rnOptionList, rnFieldList, rnDefList, rnDefItem, rnLineBlock, rnFieldName, 
+     rnFieldBody, rnStandaloneHyperlink, rnBulletList, rnEnumList: 
+    renderRstSons(d, n, result)
+  of rnDefName: 
+    result.add("\n\n")
+    result.add(ind)
+    renderRstSons(d, n, result)
+  of rnDefBody:
+    inc(d.indent, 2)
+    if n.sons[0].kind != rnBulletList: 
+      result.add("\n")
+      result.add(ind)
+      result.add("  ")
+    renderRstSons(d, n, result)
+    dec(d.indent, 2)
+  of rnField:
+    var tmp = ""
+    renderRstToRst(d, n.sons[0], tmp)
+    
+    var L = max(tmp.len + 3, 30)
+    inc(d.indent, L)
+    
+    result.add "\n"
+    result.add ind
+    result.add ':'
+    result.add tmp
+    result.add ':'
+    result.add repeatChar(L - tmp.len - 2)
+    renderRstToRst(d, n.sons[1], result)
+    
+    dec(d.indent, L)
+  of rnLineBlockItem: 
+    result.add("\n")
+    result.add(ind)
+    result.add("| ")
+    renderRstSons(d, n, result)
+  of rnBlockQuote:
+    inc(d.indent, 2)
+    renderRstSons(d, n, result)
+    dec(d.indent, 2)
+  of rnRef: 
+    result.add("`")
+    renderRstSons(d, n, result)
+    result.add("`_")
+  of rnHyperlink: 
+    result.add('`')
+    renderRstToRst(d, n.sons[0], result)
+    result.add(" <")
+    renderRstToRst(d, n.sons[1], result)
+    result.add(">`_")
+  of rnGeneralRole:
+    result.add('`')
+    renderRstToRst(d, n.sons[0],result)
+    result.add("`:")
+    renderRstToRst(d, n.sons[1],result)
+    result.add(':')
+  of rnSub: 
+    result.add('`')
+    renderRstSons(d, n, result)
+    result.add("`:sub:")
+  of rnSup: 
+    result.add('`')
+    renderRstSons(d, n, result)
+    result.add("`:sup:")
+  of rnIdx: 
+    result.add('`')
+    renderRstSons(d, n, result)
+    result.add("`:idx:")
+  of rnEmphasis: 
+    result.add("*")
+    renderRstSons(d, n, result)
+    result.add("*")
+  of rnStrongEmphasis: 
+    result.add("**")
+    renderRstSons(d, n, result)
+    result.add("**")
+  of rnTripleEmphasis:
+    result.add("***")
+    renderRstSons(d, n, result)
+    result.add("***")
+  of rnInterpretedText: 
+    result.add('`')
+    renderRstSons(d, n, result)
+    result.add('`')
+  of rnInlineLiteral: 
+    inc(d.verbatim)
+    result.add("``")
+    renderRstSons(d, n, result)
+    result.add("``")
+    dec(d.verbatim)
+  of rnSmiley:
+    result.add(n.text)
+  of rnLeaf:
+    if d.verbatim == 0 and n.text == "\\":
+      result.add("\\\\") # XXX: escape more special characters!
+    else:
+      result.add(n.text)
+  of rnIndex: 
+    result.add("\n\n")
+    result.add(ind)
+    result.add(".. index::\n")
+    
+    inc(d.indent, 3)
+    if n.sons[2] != nil: renderRstSons(d, n.sons[2], result)
+    dec(d.indent, 3)
+  of rnContents:
+    result.add("\n\n")
+    result.add(ind)
+    result.add(".. contents::")
+  else:
+    result.add("Error: cannot render: " & $n.kind)
+  
+proc renderRstToRst*(n: PRstNode, result: var string) =
+  ## renders `n` into its string representation and appends to `result`.
+  var d: TRenderContext
+  renderRstToRst(d, n, result)
+