#!/usr/bin/env python
##
# Wilfredo Sanchez, wsanchez@wsanchez.net
#
# iTunes Music Store RSS Feed parser
# http://www.wsanchez.net/itms/
##
# Copyright (c) 2002 Wilfredo Sanchez Vega.
# All rights reserved.
#
# 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 AUTHORS DISCLAIM ALL
# WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
# AUTHORS 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.
##

__version__ = "1.0"

import types
import time
import feedparser

query_new_releases    = "newreleases"
query_just_added      = "justadded"
query_top_songs       = "topsongs"
query_top_albums      = "topalbums"
query_featured_albums = "featuredalbums"

query_types = (query_new_releases,
               query_just_added,
               query_top_songs,
               query_top_albums,
               query_featured_albums)

def get(limit=None, query_type=None):
    """
    Get data from the iTunes Music Store RSS feed.

    The limit option, if given, specifies the maximum number of items
    to fetch from the feed.  The limit must be a positive integer.
    If unspecified or None, the limit defaults to 10.

    The query_type option, if given, specifies the query time, which
    may be one of the constants in query_types.
    If unspecified or None, the query_type defaults to
    query_new_releases.

    Returns a dictionary with the following keys:
    url,          URL for the feed;
    title,        Feed title;
    description,  Feed description;
    copyright,    Feed copyright;
    time-to-live, Time to live for this data;
    date,         Generation date for this data (time.struct_time object);
    items,        List of data items.

    Data items are dictionaries with the following keys:
    
    """
    if not limit     : limit      = 10
    if not query_type: query_type = query_new_releases

    if type(limit) != types.IntType or limit < 1:
        raise ValueError("limit '" + str(limit) + "' is not a positive integer")

    if query_type not in query_types:
        raise ValueError("query_type '" + str(query_type) + "' is not one of " + query_types)

    data = {}

    feed_server        = "ax.phobos.apple.com.edgesuite.net"
    feed_direct_action = "WebObjects/MZStore.woa/wpa/MRSS/" + query_type

    feed_url = ("http://" + feed_server + "/" + feed_direct_action +
                "/limit=" + str(limit) +
                "/rss.xml")

    feed = feedparser.parse(feed_url)

    if feed["status"] != 200:
        # FIXME: All 2xx codes are probably fine
        raise HTTPError("Unexpected HTTP response code (" + feed["status"] + ")")

    if feed["encoding"] != "utf-8":
        # FIXME: convert to UTF-8 rather than whine
        raise UnicodeError("Response encoding is not UTF-8 (" + feed["encoding"] + ")")

    items = []

    for feed_item in feed["items"]:
        item = {}

        genres = []
        for genre in feed_item["categories"]:
            genres.append({ "url":genre[0], "name":genre[1] })

        item["artist_name"       ] = feed_item["itms_artist"     ]
        item["artist_url"        ] = feed_item["itms_artistlink" ]
        item["album_title"       ] = feed_item["itms_album"      ]
        item["album_url"         ] = feed_item["itms_albumlink"  ]
        item["album_price"       ] = feed_item["itms_albumprice" ]
        item["album_copyright"   ] = feed_item["itms_rights"     ]
        item["album_release_date"] = feed_item["itms_releasedate"]
        item["album_art_url"     ] = feed_item["itms_coverart"   ]
        item["genres"            ] = tuple(genres)

        items.append(item)

    data["url"         ] = feed["url"]
    data["date"        ] = feed["modified"]
    data["title"       ] = feed["channel"]["title"      ]
    data["description" ] = feed["channel"]["description"]
    data["copyright"   ] = feed["channel"]["rights"     ]
    data["time-to-live"] = feed["channel"]["ttl"        ]
    data["items"       ] = tuple(items)

    return data

class HTTPError(OSError): pass

def generate_response_page(itms_data,
                           stylesheet  = None,
                           title       = None,
                           description = None):
    """
    Generate a full response page.
    """
    if not title: title = itms_data["title"]

    print 'Content-type: text/html; charset=UTF-8'
    print ''
    print '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">'
    print '<html xmlns="http://www.w3.org/1999/xhtml">'
    print '<head>'
    print ' <title>' + title + '</title>'
    print ' <link rel="alternate" type="application/rss+xml" title="RSS" href="' + itms_data["url"] + '" />'
    if stylesheet: print ' <link rel="stylesheet" href="' + stylesheet + '" type="text/css" />'
    print '</head>'
    print ''
    print ' <body>'
    generate_html_include(itms_data,
                          title       = title,
                          description = description)
    print ' </body>'
    print '</html>'

def generate_html_include(itms_data,
                          title       = None,
                          description = None):
    """
    Generate an SSI include snippet.
    """
    if not title      : title       = itms_data["title"      ]
    if not description: description = itms_data["description"]

    print ' <div id="itms-feed">'
    print '  <h1 class="title">' + title + '</h1>'
    print '  <p class="description">' + description + '</p>'
    print '  <ol class="item-list">'
    c = 0
    for item in itms_data["items"]:
        c = c + 1
        if c == 1: first = 'id="itms-first-item"'
        else: first = ''

        print '   <li class="item" ' + first + '>'
        print '    <div class="tidbit"><a href="' + item["album_url"] + '"><img class="art" src="' + item["album_art_url"] + '" /></a>'
        print '                            <a    class="album"  href="' + item["album_url"    ]      + '">' + item["album_title"       ] + '</a>   </div>'
        print '    <div class="tidbit">by  <a    class="artist" href="' + item["artist_url"   ]      + '">' + item["artist_name"       ] + '</a>   </div>'
        print '    <div class="tidbit">in  <a    class="genre"  href="' + item["genres"][0]["url"  ] + '">' + item["genres"][0]["name"]  + '</a>   </div>'
        print '    <div class="tidbit">on  <span class="release-date">'                                     + item["album_release_date"] + '</span></div>'
        print '    <div class="tidbit">for <span class="price"       >'                                     + item["album_price"       ] + '</span></div>'
        print '   </li>'
    print '   </ol>'
    print '  <div class="date">' + time.strftime("%a, %d %b %Y %H:%M:%S %Z", itms_data["date"]) + '</div>'
    print '  <div class="copyright">' + itms_data["copyright"] + '</div>'
    print ' </div>'

def run_cgi():
    """
    Run as a CGI program.
    """
    import cgi
    import cgitb; cgitb.enable()

    # State
    errors = []

    # Process form input
    form = cgi.FieldStorage()

    limit       = None
    format      = None
    stylesheet  = None
    title       = None
    description = None
    query_type  = None
    
    if form.has_key("limit"):
        try: limit = int(form["limit"].value)
        except ValueError: errors.append("Invalid size limit: " + form["limit"].value)
    
    if not len(errors):
        if form.has_key("format"     ): format      = form["format"     ].value
        if form.has_key("stylesheet" ): stylesheet  = form["stylesheet" ].value
        if form.has_key("title"      ): title       = form["title"      ].value
        if form.has_key("description"): description = form["description"].value
        if form.has_key("query"      ): query_type  = form["query"      ].value

        if query_type and query_type not in query_types:
            errors.append("Invalid query type: " + query_type)

    if not len(errors):
        try:
            # Get data
            itms_data = get(limit=limit, query_type=query_type)
        
            # Generate response
            if not format or format == "page":
                generate_response_page(itms_data,
                                       stylesheet  = stylesheet,
                                       title       = title,
                                       description = description)
            elif format == "include":
                generate_html_include(itms_data,
                                      title       = title,
                                      description = description)
            else:
                errors.append("Unknown format: " + format)

        except Exception, e:
            errors.append(e)

    if len(errors):
        print 'Content-type: text/plain; charset=UTF-8'
        print ''
        for error in errors: print str(error)

##
# Run
##

if __name__ == '__main__':
    import os
    if os.environ.has_key("GATEWAY_INTERFACE") and os.environ["GATEWAY_INTERFACE"][:4] == "CGI/":
        run_cgi()