#!/opt/local/bin/ruby

# $Id$
# $URL$

#
# Copyright (c) 2006 Ward Wouts <ward@wouts.nl>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#

@podcasts = {
	"distortedview" => {
		"rss" => 'http://www.distortedview.com/show/index.xml',
		"savedir" => '/Users/ward/ipod_sync/[books]/Distorted View',
		"rename" => [ /_(\d\d\d\d)(\d\d)/, '\2\1' ],
	},
	"tagesschau" => {
		"rss" => 'http://www.tagesschau.de/export/podcast',
		"savedir" => '/Users/ward/ipod_sync/[books]/Tagesschau',
		"delete" => true,
	},
}

require 'net/http'
require 'uri'
require 'rexml/document'

def fetch(uri_str, limit = 10)
	# You should choose better exception.
	raise ArgumentError, 'HTTP redirect too deep' if limit == 0

	response = Net::HTTP.get_response(URI.parse(uri_str))
	case response
	when Net::HTTPSuccess		then response
	when Net::HTTPRedirection	then fetch(response['location'], limit - 1)
	else
		response.error!
	end
end

def deleteold(podcast)
	Dir.open(@podcasts[podcast]["savedir"]).each {|entry|
		if File.file?("#{@podcasts[podcast]["savedir"]}/#{entry}") &&
		    ! @filelist[entry]
			puts "deleting #{entry}"
			File.unlink("#{@podcasts[podcast]["savedir"]}/#{entry}")
		end
	}
end

for podcast in @podcasts.keys.sort
	puts podcast
	res = fetch(@podcasts[podcast]["rss"])
	@filelist = {}

	xmldoc = REXML::Document.new(res.body)
	xmldoc.elements.each("rss/channel/*/enclosure") {|x|
		if ! x.attribute("url").nil?
			cast = x.attribute("url").to_s.dup
			filename = cast.dup
			filename.sub!(/^.*\//, "")
			if @podcasts[podcast]["rename"]
				filename.sub!(@podcasts[podcast]["rename"][0], @podcasts[podcast]["rename"][1])
			end
			@filelist[filename] = true
			if ! File.exists?("#{@podcasts[podcast]["savedir"]}/#{filename}")
				puts "gotta get #{@podcasts[podcast]["savedir"]}/#{filename}"
				response = fetch(cast)
				File.open("#{@podcasts[podcast]["savedir"]}/#{filename}", "w"){|f|
					f.print(response.body)
				}
			end
		end
	}
	if @podcasts[podcast]["delete"]
		deleteold(podcast)
	end
end