__license__ = 'GPL v3'
__copyright__ = '2010, Kovid Goyal <kovid@kovidgoyal.net>'
__docformat__ = 'restructuredtext en'

# All fields must have a NULL value represented as None for simple types,
# an empty list/dictionary for complex types and (None, None) for cover_data
SOCIAL_METADATA_FIELDS = frozenset((
    'tags',             # Ordered list
    'rating',           # A floating point number between 0 and 10
    'comments',         # A simple HTML enabled string
    'series',           # A simple string
    'series_index',     # A floating point number
    # Of the form { scheme1:value1, scheme2:value2}
    # For example: {'isbn':'123456789', 'doi':'xxxx', ... }
    'identifiers',
))

# The list of names that convert to identifiers when in get and set.
TOP_LEVEL_IDENTIFIERS = frozenset((
    'isbn',
))

PUBLICATION_METADATA_FIELDS = frozenset((
    'title',            # title must never be None. Should be 'Unknown'
    # Pseudo field that can be set, but if not set is auto generated
    # from title and languages
    'title_sort',
    'authors',          # Ordered list. Must never be None, can be ['Unknown']
    'author_sort_map',  # Map of sort strings for each author
    # Pseudo field that can be set, but if not set is auto generated
    # from authors and languages
    'author_sort',
    'book_producer',
    'timestamp',        # Dates and times must be timezone aware
    'pubdate',
    'last_modified',
    'rights',
    # So far only known publication type is periodical:calibre
    # If None, means book
    'publication_type',
    'uuid',             # A UUID usually of type 4
    'languages',        # ordered list of languages in this publication
    'publisher',        # Simple string, no special semantics
    # Absolute path to image file encoded in filesystem_encoding
    'cover',
    # Of the form (format, data) where format is, for e.g. 'jpeg', 'png', 'gif'...
    'cover_data',
    # Either thumbnail data, or an object with the attribute
    # image_path which is the path to an image file, encoded
    # in filesystem_encoding
    'thumbnail',
))

BOOK_STRUCTURE_FIELDS = frozenset((
    # These are used by code, Null values are None.
    'toc', 'spine', 'guide', 'manifest',
))

USER_METADATA_FIELDS = frozenset((
    # A dict of dicts similar to field_metadata. Each field description dict
    # also contains a value field with the key #value#.
    'user_metadata',
))

DEVICE_METADATA_FIELDS = frozenset((
    'device_collections',   # Ordered list of strings
    'lpath',                # Unicode, / separated
    'size',                 # In bytes
    'mime',                 # Mimetype of the book file being represented
))

CALIBRE_METADATA_FIELDS = frozenset((
    'application_id',   # An application id, currently set to the db_id.
    'db_id',            # the calibre primary key of the item.
    'formats',          # list of formats (extensions) for this book
    # a dict of user category names, where the value is a list of item names
    # from the book that are in that category
    'user_categories',
    # a dict of author to an associated hyperlink
    'author_link_map',
))

ALL_METADATA_FIELDS =      SOCIAL_METADATA_FIELDS.union(
                           PUBLICATION_METADATA_FIELDS).union(
                           BOOK_STRUCTURE_FIELDS).union(
                           USER_METADATA_FIELDS).union(
                           DEVICE_METADATA_FIELDS).union(
                           CALIBRE_METADATA_FIELDS)

# All fields except custom fields
STANDARD_METADATA_FIELDS = SOCIAL_METADATA_FIELDS.union(
                           PUBLICATION_METADATA_FIELDS).union(
                           BOOK_STRUCTURE_FIELDS).union(
                           DEVICE_METADATA_FIELDS).union(
                           CALIBRE_METADATA_FIELDS)

# Metadata fields that smart update must do special processing to copy.
SC_FIELDS_NOT_COPIED =     frozenset(('title', 'title_sort', 'authors',
                                      'author_sort', 'author_sort_map',
                                      'cover_data', 'tags', 'languages',
                                      'identifiers'))

# Metadata fields that smart update should copy only if the source is not None
SC_FIELDS_COPY_NOT_NULL =  frozenset(('device_collections', 'lpath', 'size', 'comments', 'thumbnail'))

# Metadata fields that smart update should copy without special handling
SC_COPYABLE_FIELDS =       SOCIAL_METADATA_FIELDS.union(
                           PUBLICATION_METADATA_FIELDS).union(
                           BOOK_STRUCTURE_FIELDS).union(
                           DEVICE_METADATA_FIELDS).union(
                           CALIBRE_METADATA_FIELDS) - \
                           SC_FIELDS_NOT_COPIED.union(
                           SC_FIELDS_COPY_NOT_NULL)

SERIALIZABLE_FIELDS =      SOCIAL_METADATA_FIELDS.union(
                           USER_METADATA_FIELDS).union(
                           PUBLICATION_METADATA_FIELDS).union(
                           CALIBRE_METADATA_FIELDS).union(
                           DEVICE_METADATA_FIELDS) - \
                           frozenset(('device_collections', 'formats',
                                      'cover_data'))
# these are rebuilt when needed