define_structure :Url, :channel, :nick, :time, :url, :info

class ::UrlLinkError < RuntimeError
end

class UrlPlugin < Plugin
  TITLE_RE = /<\s*?title\s*?>(.+?)<\s*?\/title\s*?>/im
  LINK_INFO = "[Link Info]"

  BotConfig.register BotConfigIntegerValue.new('url.max_urls',
    :default => 100, :validate => Proc.new{|v| v > 0},
    :desc => "Maximum number of urls to store. New urls replace oldest ones.")
  BotConfig.register BotConfigBooleanValue.new('url.display_link_info',
    :default => false,
    :desc => "Get the title of any links pasted to the channel and display it (also tells if the link is broken or the site is down)")
  BotConfig.register BotConfigBooleanValue.new('url.titles_only',
    :default => false,
    :desc => "Only show info for links that have <title> tags (in other words, don't display info for jpegs, mpegs, etc.)")
  BotConfig.register BotConfigBooleanValue.new('url.first_par',
    :default => false,
    :desc => "Also try to get the first paragraph of a web page")
  BotConfig.register BotConfigBooleanValue.new('url.info_on_list',
    :default => false,
    :desc => "Show link info when listing/searching for urls")


  def initialize
    super
    @registry.set_default(Array.new)
  end

  def help(plugin, topic="")
    "urls [<max>=4] => list <max> last urls mentioned in current channel, urls search [<max>=4] <regexp> => search for matching urls. In a private message, you must specify the channel to query, eg. urls <channel> [max], urls search <channel> [max] <regexp>"
  end

  def get_title_from_html(pagedata)
    return unless TITLE_RE.match(pagedata)
    $1.ircify_html
  end

  def get_title_for_url(uri_str)

    url = uri_str.kind_of?(URI) ? uri_str : URI.parse(uri_str)
    return if url.scheme !~ /https?/

    title = nil
    extra = String.new

    begin
      debug "+ getting #{url.request_uri}"
      @bot.httputil.get_response(url) { |resp|
        case resp
        when Net::HTTPSuccess

          debug resp.to_hash

          if resp['content-type'] =~ /^text\/|(?:x|ht)ml/
            # The page is text or HTML, so we can try finding a title and, if
            # requested, the first par.
            #
            # We act differently depending on whether we want the first par or
            # not: in the first case we download the initial part and the parse
            # it; in the second case we only download as much as we need to find
            # the title
            #
            if @bot.config['url.first_par']
              partial = resp.partial_body(@bot.config['http.info_bytes'])
              title = get_title_from_html(partial)
              first_par = Utils.ircify_first_html_par(partial, :strip => title)
              extra << ", #{Bold}text#{Bold}: #{first_par}" unless first_par.empty?
              return "#{Bold}title#{Bold}: #{title}#{extra}" if title
            else
              resp.partial_body(@bot.config['http.info_bytes']) { |part|
                title = get_title_from_html(part)
                return "#{Bold}title#{Bold}: #{title}" if title
              }
            end
          # if nothing was found, provide more basic info, as for non-html pages
          else
            resp.no_cache = true
          end

          enc = resp['content-encoding']

          extra << ", #{Bold}encoding#{Bold}: #{enc}" if enc

          unless @bot.config['url.titles_only']
            # content doesn't have title, just display info.
            size = resp['content-length'].gsub(/(\d)(?=\d{3}+(?:\.|$))(\d{3}\..*)?/,'\1,\2') rescue nil
            size = size ? ", #{Bold}size#{Bold}: #{size} bytes" : ""
            return "#{Bold}type#{Bold}: #{resp['content-type']}#{size}#{extra}"
          end
        else
          raise UrlLinkError, "getting link (#{resp.code} - #{resp.message})"
        end
      }
      return nil
    rescue Exception => e
      case e
      when UrlLinkError
        raise e
      else
        error e
        raise "connecting to site/processing information (#{e.message})"
      end
    end
  end

  def listen(m)
    return unless m.kind_of?(PrivMessage)
    return if m.address?
    # TODO support multiple urls in one line
    if m.message =~ /(f|ht)tps?:\/\//
      if m.message =~ /((f|ht)tps?:\/\/.*?)(?:\s+|$)/
        urlstr = $1
        list = @registry[m.target]

        title = nil
        if @bot.config['url.display_link_info']
          Thread.start do
            debug "Getting title for #{urlstr}..."
            begin
              title = get_title_for_url urlstr
              if title
                m.reply "#{LINK_INFO} #{title}", :overlong => :truncate
                debug "Title found!"
              else
                debug "Title not found!"
              end
            rescue => e
              m.reply "Error #{e.message}"
            end
          end
        end

        # check to see if this url is already listed
        return if list.find {|u| u.url == urlstr }

        url = Url.new(m.target, m.sourcenick, Time.new, urlstr, title)
        debug "#{list.length} urls so far"
        if list.length > @bot.config['url.max_urls']
          list.pop
        end
        debug "storing url #{url.url}"
        list.unshift url
        debug "#{list.length} urls now"
        @registry[m.target] = list
      end
    end
  end

  def reply_urls(opts={})
    list = opts[:list]
    max = opts[:max]
    channel = opts[:channel]
    m = opts[:msg]
    return unless list and max and m
    list[0..(max-1)].each do |url|
      disp = "[#{url.time.strftime('%Y/%m/%d %H:%M:%S')}] <#{url.nick}> #{url.url}"
      if @bot.config['url.info_on_list']
        title = url.info || get_title_for_url(url.url) rescue nil
        # If the url info was missing and we now have some, try to upgrade it
        if channel and title and not url.info
          ll = @registry[channel]
          debug ll
          if el = ll.find { |u| u.url == url.url }
            el.info = title
            @registry[channel] = ll
          end
        end
        disp << " --> #{title}" if title
      end
      m.reply disp, :overlong => :truncate
    end
  end

  def urls(m, params)
    channel = params[:channel] ? params[:channel] : m.target
    max = params[:limit].to_i
    max = 10 if max > 10
    max = 1 if max < 1
    list = @registry[channel]
    if list.empty?
      m.reply "no urls seen yet for channel #{channel}"
    else
      reply_urls :msg => m, :channel => channel, :list => list, :max => max
    end
  end

  def search(m, params)
    channel = params[:channel] ? params[:channel] : m.target
    max = params[:limit].to_i
    string = params[:string]
    max = 10 if max > 10
    max = 1 if max < 1
    regex = Regexp.new(string, Regexp::IGNORECASE)
    list = @registry[channel].find_all {|url|
      regex.match(url.url) || regex.match(url.nick) ||
        (@bot.config['url.info_on_list'] && regex.match(url.info))
    }
    if list.empty?
      m.reply "no matches for channel #{channel}"
    else
      reply_urls :msg => m, :channel => channel, :list => list, :max => max
    end
  end
end

plugin = UrlPlugin.new
plugin.map 'urls search :channel :limit :string', :action => 'search',
                          :defaults => {:limit => 4},
                          :requirements => {:limit => /^\d+$/},
                          :public => false
plugin.map 'urls search :limit :string', :action => 'search',
                          :defaults => {:limit => 4},
                          :requirements => {:limit => /^\d+$/},
                          :private => false
plugin.map 'urls :channel :limit', :defaults => {:limit => 4},
                          :requirements => {:limit => /^\d+$/},
                          :public => false
plugin.map 'urls :limit', :defaults => {:limit => 4},
                          :requirements => {:limit => /^\d+$/},
                          :private => false