#!/usr/bin/env python2
# vim:fileencoding=UTF-8:ts=4:sw=4:sta:et:sts=4:ai
from __future__ import (unicode_literals, division, absolute_import,
                        print_function)

__license__   = 'GPL v3'
__copyright__ = '2011, Kovid Goyal <kovid@kovidgoyal.net>'
__docformat__ = 'restructuredtext en'



from calibre.ebooks.metadata import check_isbn
from calibre.ebooks.metadata.sources.base import Source, Option
from calibre.utils.icu import lower
from calibre.ebooks.metadata.book.base import Metadata

BASE_URL = 'http://isbndb.com/api/books.xml?access_key=%s&page_number=1&results=subjects,authors,texts&'


class ISBNDB(Source):

    name = 'ISBNDB'
    description = _('Downloads metadata from isbndb.com')

    capabilities = frozenset(['identify'])
    touched_fields = frozenset(['title', 'authors',
        'identifier:isbn', 'comments', 'publisher'])
    supports_gzip_transfer_encoding = True
    # Shortcut, since we have no cached cover URLS
    cached_cover_url_is_reliable = False

    options = (
            Option('isbndb_key', 'string', None, _('IsbnDB key:'),
                _('To use isbndb.com you have to sign up for a free account '
                    'at isbndb.com and get an access key.')),
            )

    config_help_message = '<p>'+_('To use metadata from isbndb.com you must sign'
            ' up for a free account and get an isbndb key and enter it below.'
            ' Instructions to get the key are '
            '<a href="http://isbndb.com/docs/api/30-keys.html">here</a>.')


    def __init__(self, *args, **kwargs):
        Source.__init__(self, *args, **kwargs)

        prefs = self.prefs
        prefs.defaults['key_migrated'] = False
        prefs.defaults['isbndb_key'] = None

        if not prefs['key_migrated']:
            prefs['key_migrated'] = True
            try:
                from calibre.customize.ui import config
                key = config['plugin_customization']['IsbnDB']
                prefs['isbndb_key'] = key
            except:
                pass

    @property
    def isbndb_key(self):
        return self.prefs['isbndb_key']

    def is_configured(self):
        return self.isbndb_key is not None

    def create_query(self, title=None, authors=None, identifiers={}): # {{{
        from urllib import quote
        base_url = BASE_URL%self.isbndb_key
        isbn = check_isbn(identifiers.get('isbn', None))
        q = ''
        if isbn is not None:
            q = 'index1=isbn&value1='+isbn
        elif title or authors:
            tokens = []
            title_tokens = list(self.get_title_tokens(title))
            tokens += title_tokens
            author_tokens = self.get_author_tokens(authors,
                    only_first_author=True)
            tokens += author_tokens
            tokens = [quote(t.encode('utf-8') if isinstance(t, unicode) else t) for t in tokens]
            q = '+'.join(tokens)
            q = 'index1=combined&value1='+q

        if not q:
            return None
        if isinstance(q, unicode):
            q = q.encode('utf-8')
        return base_url + q
    # }}}

    def identify(self, log, result_queue, abort, title=None, authors=None, # {{{
            identifiers={}, timeout=30):
        if not self.is_configured():
            return
        query = self.create_query(title=title, authors=authors,
                identifiers=identifiers)
        if not query:
            err = 'Insufficient metadata to construct query'
            log.error(err)
            return err

        results = []
        try:
            results = self.make_query(query, abort, title=title, authors=authors,
                    identifiers=identifiers, timeout=timeout)
        except:
            err = 'Failed to make query to ISBNDb, aborting.'
            log.exception(err)
            return err

        if not results and identifiers.get('isbn', False) and title and authors and \
                not abort.is_set():
            return self.identify(log, result_queue, abort, title=title,
                    authors=authors, timeout=timeout)

        for result in results:
            self.clean_downloaded_metadata(result)
            result_queue.put(result)

    def parse_feed(self, feed, seen, orig_title, orig_authors, identifiers):
        from lxml import etree

        def tostring(x):
            if x is None:
                return ''
            return etree.tostring(x, method='text', encoding=unicode).strip()

        orig_isbn = identifiers.get('isbn', None)
        title_tokens = list(self.get_title_tokens(orig_title))
        author_tokens = list(self.get_author_tokens(orig_authors))
        results = []

        def ismatch(title, authors):
            authors = lower(' '.join(authors))
            title = lower(title)
            match = not title_tokens
            for t in title_tokens:
                if lower(t) in title:
                    match = True
                    break
            amatch = not author_tokens
            for a in author_tokens:
                if lower(a) in authors:
                    amatch = True
                    break
            if not author_tokens: amatch = True
            return match and amatch

        bl = feed.find('BookList')
        if bl is None:
            err = tostring(feed.find('errormessage'))
            raise ValueError('ISBNDb query failed:' + err)
        total_results = int(bl.get('total_results'))
        shown_results = int(bl.get('shown_results'))
        for bd in bl.xpath('.//BookData'):
            isbn = check_isbn(bd.get('isbn', None))
            isbn13 = check_isbn(bd.get('isbn13', None))
            if not isbn and not isbn13:
                continue
            if orig_isbn and orig_isbn not in {isbn, isbn13}:
                continue
            title = tostring(bd.find('Title'))
            if not title:
                continue
            authors = []
            for au in bd.xpath('.//Authors/Person'):
                au = tostring(au)
                if au:
                    if ',' in au:
                        ln, _, fn = au.partition(',')
                        au = fn.strip() + ' ' + ln.strip()
                authors.append(au)
            if not authors:
                continue
            comments = tostring(bd.find('Summary'))
            id_ = (title, tuple(authors))
            if id_ in seen:
                continue
            seen.add(id_)
            if not ismatch(title, authors):
                continue
            publisher = tostring(bd.find('PublisherText'))
            if not publisher: publisher = None
            if publisher and 'audio' in publisher.lower():
                continue
            mi = Metadata(title, authors)
            mi.isbn = isbn
            mi.publisher = publisher
            mi.comments = comments
            results.append(mi)
        return total_results, shown_results, results

    def make_query(self, q, abort, title=None, authors=None, identifiers={},
            max_pages=10, timeout=30):
        from lxml import etree
        from calibre.ebooks.chardet import xml_to_unicode
        from calibre.utils.cleantext import clean_ascii_chars

        page_num = 1
        parser = etree.XMLParser(recover=True, no_network=True)
        br = self.browser

        seen = set()

        candidates = []
        total_found = 0
        while page_num <= max_pages and not abort.is_set():
            url = q.replace('&page_number=1&', '&page_number=%d&'%page_num)
            page_num += 1
            raw = br.open_novisit(url, timeout=timeout).read()
            feed = etree.fromstring(xml_to_unicode(clean_ascii_chars(raw),
                strip_encoding_pats=True)[0], parser=parser)
            total, found, results = self.parse_feed(
                    feed, seen, title, authors, identifiers)
            total_found += found
            candidates += results
            if total_found >= total or len(candidates) > 9:
                break

        return candidates
    # }}}

if __name__ == '__main__':
    # To run these test use:
    # calibre-debug -e src/calibre/ebooks/metadata/sources/isbndb.py
    from calibre.ebooks.metadata.sources.test import (test_identify_plugin,
            title_test, authors_test)
    test_identify_plugin(ISBNDB.name,
        [


            (
                {'title':'Great Gatsby',
                    'authors':['Fitzgerald']},
                [title_test('The great gatsby', exact=True),
                    authors_test(['F. Scott Fitzgerald'])]
            ),

            (
                {'title': 'Flatland', 'authors':['Abbott']},
                [title_test('Flatland', exact=False)]
            ),
    ])

