#
# Copyright (C) 2007 Mobio Networks, Inc.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#

=begin
Some summary should go here
=end
 
#require 'rexml/document'
require 'open-uri' 
require 'hpricot'

module Rmobio
  module Utils

    #== cachControl
    #=== Adding cache control to response header 
    def cacheControl(cacheStr='priority=P3;max-age=604800')  
      headers.delete("Cache-Control");
      headers["Cache-Control"] = cacheStr;   
    end
     
    
    #== cacheloader
    #=== A utility method to add cache control to images, styles and files
    # To add a cache control, edit the configuration file 'cachehints.txt' with 
    # filename and header. Here is a ample configuration:
    # 
    # 
    #<tt>logo.png: priority=P2;max-age=1296000</tt>
    #
    #<tt>base.rhtml: priority=P2;max-age=1296000</tt>
    #
    #   
    # The utility assumes base directory for images files in RAILS_ROOT/public/images 
    # and other files in RAILS_ROOT/apps/views.
    # 
    # 
    # To access the image in your xform, use the following pattern:
    #<tt><icon>recipe/loader?name=logo.png</icon></tt>
    # To access the style in your xform, use the following pattern:
    #<tt><style xmlns="http://www.mobio.com/ext" src="recipe/loader?name=layouts/base.rhtml"/></tt>
    #
    # where the controller 'recipe' should provide a method 'loader' that calls this
    # utility:
    #  def loader
    #    cacheloader
    #  end
    # 
    def cacheloader 
      if (name=params[:name]).nil?
        # Can't do anything, just return empty content so we don't get 
        # 'no template' error.
        render :text => ''
        return
      end

      # Default cache configuration file
      cache_hints = File::join RAILS_ROOT, 'public/cachehints.txt' 

      # Add cache header
      headers.delete("Cache-Control")  
      if File.file?(cache_hints)
        file = File.new(cache_hints,"r")
        hintsTxt = file.read(File.size(cache_hints))
        file.close()
        hintsTxt.each_line do |line|
          if line.index(name) == 0
            line.scan(/(.*):(.*)/) do |garbage, ccheader|
              headers["Cache-Control"] = ccheader.strip
            end
            break
          end
        end
      end

      if name=~ /.png$/
        # for now hardcode the image directory
        filePath = File::join RAILS_ROOT, 'public/images/', name 
        file = File.new(filePath,"r")
        filecontents = file.read(File.size(filePath))
        file.close()

        headers["Content-Type"] = "image/png"

        render :text => filecontents
        return
      elsif name =~ /.xfs$/ or name =~ /.rxf/ 
        headers["Content-Type"] = "application/mform" 
      else 
        headers["Content-Type"] = "application/xml"
      end 

      render :template => name   
    end

    #== cacheimg
    #=== A utility method to add cache control to images
    #=== This utility is deprecated, use cacheloader instead
    # To add a cache control for an image file in RAILS_ROOT/public/images, edit
    # the configuration file "cachehints.txt with image name and header. Ex:
    # 
    # logo.png: priority=P2;max-age=1296000
    # 
    # To access the image in your xforms, use the following pattern:
    # <icon>img?name=logo.png</icon>
    # Where the controller should provide an img method that just call this cacheimg utility.
    #  
    # Sample cachehints.txt:
    # Skins_176A2-a.png: priority=P2;max-age=1296000
    # logo.png: priority=P2;max-age=1296000
    # 
    def cacheimg
      public_folder = File::join RAILS_ROOT, "public/images"
      filePath = File::join RAILS_ROOT, "public/images", params['name'] 
      file = File.new(filePath,"r")
      filecontents = file.read(File.size(filePath))
      file.close()


      headers["Content-Type"] = "image/png"
      headers.delete("Cache-Control")
      fileDir = File.dirname(filePath)
      fileName = File.basename(filePath)
      hints = File::join fileDir, "cachehints.txt"
      if File.file?(hints)
        file = File.new(hints,"r")
        hintsTxt = file.read(File.size(hints))
        file.close()
        hintsTxt.each_line do |line|
          if line.index(fileName) == 0
            line.scan(/(.*):(.*)/) do |garbage, ccheader|
              headers["Cache-Control"] = ccheader.strip
            end
            break
          end
        end
      end
      render :text => filecontents
    end

    #== backURL(key)
    # This utility handles back url to GLP if page is cached. 
    # It expects params[:burl] or a session key and renders 
    # the following xml data back to the caller: 
    # 
    # <data xmlns="">
    #  <burl>blah blah url</burl>
    # </data>
    #  
    # The returned instance data <burl> is determined by the following rules:
    #* params[:burl] if parameter exists, the url in the session is also updated
    #* session[:key] if params[:burl] is nil
    #* empty string if none of the above
    # 
    #
    # To access the backurl from your xfroms, use the following pattern:
    # 
    #   <xf:instance id="homepage" src="storeBackurl?burl=SOMEURL" />  
    #   
    # Where the controller should provide a "storeBackurl" method that just call this backURL utility:
    #   def storeBackurl
    #     backURL("recipe_burl")
    #   end  
    # 
    #=== Parameter
    # key  =>  a unique session key to store the burl for the app
    # 
    def backURL(key) 
      url = backurl_xml(key)
      headers['Content-Type']='application/xml' 
      render :text => "<data xmlns=\"\">" + url  + "</data>"
    end  # end backURLg

    # if you want to just return partial backurl without headers and no rendering
    def backurl_xml(key)
      if params[:burl]
        url =  params[:burl].gsub(/&/,'&amp;')
        session[key] = url
      elsif session[key]
        url = session[key]
      else 
        # don't know what to do, just return an empty url
        url = ''
      end 
      logger.debug('back url ' + key + ': ' + url)
      "<burl>" + url  + "</burl>"
    end # end backurl_xml
      
    def logHeaders
      logger.debug( "Logging Headers...")
      request.env.keys.each do |header|
        logger.debug( header.to_s + ': ' + request.env[header].to_s)
      end
      logger.debug("End of Headers...")
    end
    

  end #end Utils
end  #end Mobio