Checkout of Instiki Trunk 1/21/2007.

lib/chunks/wiki.rb

@@ -0,0 +1,143 @@
+require 'wiki_words'
+require 'chunks/chunk'
+require 'chunks/wiki'
+require 'cgi'
+
+# Contains all the methods for finding and replacing wiki related links.
+module WikiChunk
+  include Chunk
+
+  # A wiki reference is the top-level class for anything that refers to
+  # another wiki page.
+  class WikiReference < Chunk::Abstract
+
+    # Name of the referenced page
+    attr_reader :page_name
+    
+    # the referenced page
+    def refpage
+      @content.web.page(@page_name)
+    end
+  
+  end
+
+  # A wiki link is the top-level class for links that refers to
+  # another wiki page.
+  class WikiLink < WikiReference
+ 
+    attr_reader :link_text, :link_type
+
+    def initialize(match_data, content)
+      super
+      @link_type = :show
+    end
+
+    def self.apply_to(content)
+      content.gsub!( self.pattern ) do |matched_text|
+        chunk = self.new($~, content)
+        if chunk.textile_url?
+          # do not substitute
+          matched_text
+        else
+          content.add_chunk(chunk)
+          chunk.mask
+        end
+      end
+    end
+
+    def textile_url?
+      not @textile_link_suffix.nil?
+    end
+
+    # replace any sequence of whitespace characters with a single space
+    def normalize_whitespace(line)
+      line.gsub(/\s+/, ' ')
+    end
+  
+  end
+
+  # This chunk matches a WikiWord. WikiWords can be escaped
+  # by prepending a '\'. When this is the case, the +escaped_text+
+  # method will return the WikiWord instead of the usual +nil+.
+  # The +page_name+ method returns the matched WikiWord.
+  class Word < WikiLink
+
+    attr_reader :escaped_text
+    
+    unless defined? WIKI_WORD
+      WIKI_WORD = Regexp.new('(":)?(\\\\)?(' + WikiWords::WIKI_WORD_PATTERN + ')\b', 0, "utf-8")
+    end
+
+    def self.pattern
+      WIKI_WORD
+    end
+
+    def initialize(match_data, content)
+      super
+      @textile_link_suffix, @escape, @page_name = match_data[1..3]
+      if @escape 
+        @unmask_mode = :escape
+        @escaped_text = @page_name
+      else
+        @escaped_text = nil
+      end
+      @link_text = WikiWords.separate(@page_name)
+      @unmask_text = (@escaped_text || @content.page_link(@page_name, @link_text, @link_type))
+    end
+
+  end
+
+  # This chunk handles [[bracketted wiki words]] and 
+  # [[AliasedWords|aliased wiki words]]. The first part of an
+  # aliased wiki word must be a WikiWord. If the WikiWord
+  # is aliased, the +link_text+ field will contain the
+  # alias, otherwise +link_text+ will contain the entire
+  # contents within the double brackets.
+  #
+  # NOTE: This chunk must be tested before WikiWord since
+  #       a WikiWords can be a substring of a WikiLink. 
+  class Link < WikiLink
+    
+    unless defined? WIKI_LINK
+      WIKI_LINK = /(":)?\[\[\s*([^\]\s][^\]]+?)\s*\]\]/
+      LINK_TYPE_SEPARATION = Regexp.new('^(.+):((file)|(pic))$', 0, 'utf-8')
+      ALIAS_SEPARATION = Regexp.new('^(.+)\|(.+)$', 0, 'utf-8')
+    end    
+        
+    def self.pattern() WIKI_LINK end
+
+    def initialize(match_data, content)
+      super
+      @textile_link_suffix = match_data[1]
+      @link_text = @page_name = normalize_whitespace(match_data[2])
+      separate_link_type
+      separate_alias
+      @unmask_text = @content.page_link(@page_name, @link_text, @link_type)
+    end
+
+    private
+
+    # if link wihin the brackets has a form of [[filename:file]] or [[filename:pic]], 
+    # this means a link to a picture or a file
+    def separate_link_type
+      link_type_match = LINK_TYPE_SEPARATION.match(@page_name)
+      if link_type_match
+        @link_text = @page_name = link_type_match[1]
+        @link_type = link_type_match[2..3].compact[0].to_sym
+      end
+    end
+
+    # link text may be different from page name. this will look like [[actual page|link text]]
+    def separate_alias
+      alias_match = ALIAS_SEPARATION.match(@page_name)
+      if alias_match
+        @page_name = normalize_whitespace(alias_match[1])
+        @link_text = alias_match[2]
+      end
+      # note that [[filename|link text:file]] is also supported
+    end  
+  
+  end
+
+  
+end