module ForumHelper

  def wrap(s, n)
    Wraptools.wrap_ff(s, n)
  end

  # Calculates the difference between time and sysdate, and rewrites it as text, 
  # e.g. "3 days ago"
  # At present, this is not used anywhere in the code. There is an intention to use it in 
  # forum/show action ('this topis was edited 4 centuries ago')
  def format_relative_time(time)
    interval = (Time.now - time)
    seconds = (interval).to_i
    minutes = (interval / 60).to_i
    hours = (interval / (60*60)).to_i
    days = (interval / (60*60*24)).to_i

    if days == 0
      if hours == 0
        if minutes == 0
          return l(:seconds_ago, seconds)
        end
        return l(:minutes_ago, minutes)
      end
      return l(:hours_ago, hours)
    end
    
    if days == 1
      return l(:yesterday)
    else
      return l(:days_ago, days)
    end
  end

  # Extract a small part of the text to show in the search results.
  def searchresult_text_excerpt(text, query)
    excerpt = h(text[0,100])
    if text.size > 100
      excerpt << '...'
    end

    # hilight searched words
    words = query.split
    words.each do |word|
      begin
        excerpt[word] =  '<em>' + word + '</em>'
      rescue
      end
    end
    excerpt
  end

  # Color quoting levels in a string. Use CGI::escapeHTML before doing this.
  def color_quoting(s)
    s.gsub(/\r\n/, "\n").gsub(/(^)((&gt;)+)(.*?)$/m) do |match|
      '<span class="quoting-level-' + ($2.size / 4).to_s + '">' + $2 + $4 + '</span>'
    end
  end
  
  def format_post_text_new(s)
    #color_quoting(h(s))
    s = h(Wraptools::unwrap_quoted(s))

    parts = []
    s.gsub(/\r\n/, "\n").scan(/(^)((&gt;)*)(.*?)$/m) do |match|
      line = $4
      level = $2.size / 4
      if level > 0
        # remove leading space after ">" is removed
        line.sub!(/^ /, '')
      end
      
      # convert leading spaces to &nbsp;
      line.sub!(/^( *)/, '')
      line = '&nbsp;' * $1.size + line
      
      parts << [line, level]
    end

    cur_level = -1
    s = ''
    parts.each do |line, level|
      if level > cur_level
        while level > cur_level do
          cur_level += 1
          s << '<div class="quoting level-' + cur_level.to_s + '">'
        end
      elsif level < cur_level
        while level < cur_level do
          s << '</div>'
          cur_level -= 1
        end
      end

      if line =~ /schrieb:$/
        line = '<span class="author-level-' +
          (cur_level + 1).to_s + '">' + line + '</span>'
      end
      
      s << line
      s << "<br />"
    end

    while 0 <= cur_level do
      s << '</div>' 
      cur_level -= 1
    end 
    
    s
  end
  
  # Converts urls in a string to links.
  # The string has to be html-escaped (CGI::escapeHTML)
  def url_to_link(s)
    url_regex= /(http:\/\/[^)\s]+[^.?!\)\]\s])/is
    s.gsub(url_regex) do |match|
      url = $1
      '<a href="' +
      ('http://' if url =~ /^www/).to_s + 
      url +
      '" rel="nofollow">' +
      url + 
      '</a>'
    end
  end
  
end