# -*- ruby -*-
#
# Copyright (C) 2009 Cathal Mc Ginley
#
# Alexandria 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 2 of the
# License, or (at your option) any later version.
#
# Alexandria 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 Alexandria; see the file COPYING.  If not,
# write to the Free Software Foundation, Inc., 51 Franklin Street,
# Fifth Floor, Boston, MA 02110-1301 USA.

# author Sun Ning <classicning@gmail.com>, http://sunng.info/
# Douban.com book repository.
# see http://book.douban.com/
#

require 'cgi'
require 'alexandria/net'
require 'json'

module Alexandria
	class BookProviders
		class DoubanProvider < GenericProvider
			include Alexandria::Logging
			
			BASE_URL = "http://api.douban.com/book/subjects?q=%s&max-results=5&alt=json"

			def initialize()
				super("Douban", "Douban (China)")
			end
			
			def search(criterion, type)
				keyword = criterion
				request_url = BASE_URL % CGI.escape(keyword)
				
				search_response = transport.get_response(URI.parse(request_url))
				
				results = parse_search_result(search_response.body)
				if results.length == 0
					raise NoResultsError
				end

				if type == SEARCH_BY_ISBN
					return results.first
				else
					return results
				end
			end


			def parse_search_result(response)
				book_search_results = []
				begin
					dbresult = JSON.parse(response)
					if(dbresult['opensearch:totalResults']['$t'].to_i > 0)
						for item in dbresult['entry']
							name = item['title']['$t']
							isbn = nil
							publisher = nil
							pubdate = nil
							binding = nil
							for av in item['db:attribute']:
								if av['@name'] == 'isbn13':
									isbn = av['$t']
								end
								if av['@name'] == 'publisher':
									publisher = av['$t']
								end
								if av['@name'] == 'pubdate':
									pubdate = av['$t']
								end
								if av['@name'] == 'binding':
									binding = av['$t']
								end
							end
							authors = item['author'].map{ |a| a['name']['$t'] }
							image_url = nil
							for av in item['link']:
								if av['@rel'] == 'image':
									image_url = av['@href']
								end
							end
							book = Book.new(name, authors, isbn, publisher, pubdate, binding)
							book_search_results << [ book, image_url ]
						end
					end
				rescue Exception => ex
					log.warn(ex.backtrace.join('\n'))
				end
				book_search_results
			end
		end
	end
end