# -*- coding: utf-8 -*-

#  This file is part of the Calibre-Web (https://github.com/janeczku/calibre-web)
#    Copyright (C) 2018-2019 OzzieIsaacs, cervinko, jkrehm, bodybybuddha, ok11,
#                            andy29485, idalin, Kyosfonica, wuqi, Kennyl, lemmsh,
#                            falgh1, grunjol, csitko, ytils, xybydy, trasba, vrabe,
#                            ruben-herold, marblepebble, JackED42, SiphonSquirrel,
#                            apetresc, nanu-c, mutschler
#
#  This program 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 3 of the License, or
#  (at your option) any later version.
#
#  This program 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 this program. If not, see <http://www.gnu.org/licenses/>.

from __future__ import division, print_function, unicode_literals
import os
from datetime import datetime
import json
from shutil import copyfile
from uuid import uuid4

from flask import Blueprint, request, flash, redirect, url_for, abort, Markup, Response
from flask_babel import gettext as _
from flask_login import current_user, login_required
from sqlalchemy.exc import OperationalError

from . import constants, logger, isoLanguages, gdriveutils, uploader, helper
from . import config, get_locale, ub, worker, db
from . import calibre_db
from .web import login_required_if_no_ano, render_title_template, edit_required, upload_required


editbook = Blueprint('editbook', __name__)
log = logger.create()


# Modifies different Database objects, first check if elements have to be added to database, than check
# if elements have to be deleted, because they are no longer used
def modify_database_object(input_elements, db_book_object, db_object, db_session, db_type):
    # passing input_elements not as a list may lead to undesired results
    if not isinstance(input_elements, list):
        raise TypeError(str(input_elements) + " should be passed as a list")
    changed = False
    input_elements = [x for x in input_elements if x != '']
    # we have all input element (authors, series, tags) names now
    # 1. search for elements to remove
    del_elements = []
    for c_elements in db_book_object:
        found = False
        if db_type == 'languages':
            type_elements = c_elements.lang_code
        elif db_type == 'custom':
            type_elements = c_elements.value
        else:
            type_elements = c_elements.name
        for inp_element in input_elements:
            if inp_element.lower() == type_elements.lower():
                # if inp_element == type_elements:
                found = True
                break
        # if the element was not found in the new list, add it to remove list
        if not found:
            del_elements.append(c_elements)
    # 2. search for elements that need to be added
    add_elements = []
    for inp_element in input_elements:
        found = False
        for c_elements in db_book_object:
            if db_type == 'languages':
                type_elements = c_elements.lang_code
            elif db_type == 'custom':
                type_elements = c_elements.value
            else:
                type_elements = c_elements.name
            if inp_element == type_elements:
                found = True
                break
        if not found:
            add_elements.append(inp_element)
    # if there are elements to remove, we remove them now
    if len(del_elements) > 0:
        for del_element in del_elements:
            db_book_object.remove(del_element)
            changed = True
            if len(del_element.books) == 0:
                db_session.delete(del_element)
    # if there are elements to add, we add them now!
    if len(add_elements) > 0:
        if db_type == 'languages':
            db_filter = db_object.lang_code
        elif db_type == 'custom':
            db_filter = db_object.value
        else:
            db_filter = db_object.name
        for add_element in add_elements:
            # check if a element with that name exists
            db_element = db_session.query(db_object).filter(db_filter == add_element).first()
            # if no element is found add it
            # if new_element is None:
            if db_type == 'author':
                new_element = db_object(add_element, helper.get_sorted_author(add_element.replace('|', ',')), "")
            elif db_type == 'series':
                new_element = db_object(add_element, add_element)
            elif db_type == 'custom':
                new_element = db_object(value=add_element)
            elif db_type == 'publisher':
                new_element = db_object(add_element, None)
            else:  # db_type should be tag or language
                new_element = db_object(add_element)
            if db_element is None:
                changed = True
                db_session.add(new_element)
                db_book_object.append(new_element)
            else:
                if db_type == 'custom':
                    if db_element.value != add_element:
                        new_element.value = add_element
                elif db_type == 'languages':
                    if db_element.lang_code != add_element:
                        db_element.lang_code = add_element
                elif db_type == 'series':
                    if db_element.name != add_element:
                        db_element.name = add_element
                        db_element.sort = add_element
                elif db_type == 'author':
                    if db_element.name != add_element:
                        db_element.name = add_element
                        db_element.sort = add_element.replace('|', ',')
                elif db_type == 'publisher':
                    if db_element.name != add_element:
                        db_element.name = add_element
                        db_element.sort = None
                elif db_element.name != add_element:
                    db_element.name = add_element
                # add element to book
                changed = True
                db_book_object.append(db_element)
    return changed


def modify_identifiers(input_identifiers, db_identifiers, db_session):
    """Modify Identifiers to match input information.
       input_identifiers is a list of read-to-persist Identifiers objects.
       db_identifiers is a list of already persisted list of Identifiers objects."""
    changed = False
    error = False
    input_dict = dict([(identifier.type.lower(), identifier) for identifier in input_identifiers])
    if len(input_identifiers) != len(input_dict):
        error = True
    db_dict = dict([(identifier.type.lower(), identifier) for identifier in db_identifiers ])
    # delete db identifiers not present in input or modify them with input val
    for identifier_type, identifier in db_dict.items():
        if identifier_type not in input_dict.keys():
            db_session.delete(identifier)
            changed = True
        else:
            input_identifier = input_dict[identifier_type]
            identifier.type = input_identifier.type
            identifier.val = input_identifier.val
    # add input identifiers not present in db
    for identifier_type, identifier in input_dict.items():
        if identifier_type not in db_dict.keys():
            db_session.add(identifier)
            changed = True
    return changed, error


@editbook.route("/delete/<int:book_id>/", defaults={'book_format': ""})
@editbook.route("/delete/<int:book_id>/<string:book_format>/")
@login_required
def delete_book(book_id, book_format):
    if current_user.role_delete_books():
        book = calibre_db.get_book(book_id)
        if book:
            try:
                result, error = helper.delete_book(book, config.config_calibre_dir, book_format=book_format.upper())
                if not result:
                    flash(error, category="error")
                    return redirect(url_for('editbook.edit_book', book_id=book_id))
                if error:
                    flash(error, category="warning")
                if not book_format:
                    # delete book from Shelfs, Downloads, Read list
                    ub.session.query(ub.BookShelf).filter(ub.BookShelf.book_id == book_id).delete()
                    ub.session.query(ub.ReadBook).filter(ub.ReadBook.book_id == book_id).delete()
                    ub.delete_download(book_id)
                    ub.session.commit()

                    # check if only this book links to:
                    # author, language, series, tags, custom columns
                    modify_database_object([u''], book.authors, db.Authors, calibre_db.session, 'author')
                    modify_database_object([u''], book.tags, db.Tags, calibre_db.session, 'tags')
                    modify_database_object([u''], book.series, db.Series, calibre_db.session, 'series')
                    modify_database_object([u''], book.languages, db.Languages, calibre_db.session, 'languages')
                    modify_database_object([u''], book.publishers, db.Publishers, calibre_db.session, 'publishers')

                    cc = calibre_db.session.query(db.Custom_Columns).\
                        filter(db.Custom_Columns.datatype.notin_(db.cc_exceptions)).all()
                    for c in cc:
                        cc_string = "custom_column_" + str(c.id)
                        if not c.is_multiple:
                            if len(getattr(book, cc_string)) > 0:
                                if c.datatype == 'bool' or c.datatype == 'integer' or c.datatype == 'float':
                                    del_cc = getattr(book, cc_string)[0]
                                    getattr(book, cc_string).remove(del_cc)
                                    log.debug('remove ' + str(c.id))
                                    calibre_db.session.delete(del_cc)
                                    calibre_db.session.commit()
                                elif c.datatype == 'rating':
                                    del_cc = getattr(book, cc_string)[0]
                                    getattr(book, cc_string).remove(del_cc)
                                    if len(del_cc.books) == 0:
                                        log.debug('remove ' + str(c.id))
                                        calibre_db.session.delete(del_cc)
                                        calibre_db.session.commit()
                                else:
                                    del_cc = getattr(book, cc_string)[0]
                                    getattr(book, cc_string).remove(del_cc)
                                    log.debug('remove ' + str(c.id))
                                    calibre_db.session.delete(del_cc)
                                    calibre_db.session.commit()
                        else:
                            modify_database_object([u''], getattr(book, cc_string), db.cc_classes[c.id],
                                                   calibre_db.session, 'custom')
                    calibre_db.session.query(db.Books).filter(db.Books.id == book_id).delete()
                else:
                    calibre_db.session.query(db.Data).filter(db.Data.book == book.id).\
                        filter(db.Data.format == book_format).delete()
                calibre_db.session.commit()
            except Exception as e:
                log.debug(e)
                calibre_db.session.rollback()
        else:
            # book not found
            log.error('Book with id "%s" could not be deleted: not found', book_id)
    if book_format:
        flash(_('Book Format Successfully Deleted'), category="success")
        return redirect(url_for('editbook.edit_book', book_id=book_id))
    else:
        flash(_('Book Successfully Deleted'), category="success")
        return redirect(url_for('web.index'))


def render_edit_book(book_id):
    calibre_db.update_title_sort(config)
    cc = calibre_db.session.query(db.Custom_Columns).filter(db.Custom_Columns.datatype.notin_(db.cc_exceptions)).all()
    book = calibre_db.get_filtered_book(book_id)
    if not book:
        flash(_(u"Error opening eBook. File does not exist or file is not accessible"), category="error")
        return redirect(url_for("web.index"))

    for lang in book.languages:
        lang.language_name = isoLanguages.get_language_name(get_locale(), lang.lang_code)

    book = calibre_db.order_authors(book)

    author_names = []
    for authr in book.authors:
        author_names.append(authr.name.replace('|', ','))

    # Option for showing convertbook button
    valid_source_formats=list()
    allowed_conversion_formats = list()
    kepub_possible=None
    if config.config_converterpath:
        for file in book.data:
            if file.format.lower() in constants.EXTENSIONS_CONVERT:
                valid_source_formats.append(file.format.lower())
    if config.config_kepubifypath and 'epub' in [file.format.lower() for file in book.data]:
        kepub_possible = True
        if not config.config_converterpath:
            valid_source_formats.append('epub')

    # Determine what formats don't already exist
    if config.config_converterpath:
        allowed_conversion_formats = constants.EXTENSIONS_CONVERT[:]
        for file in book.data:
            if file.format.lower() in allowed_conversion_formats:
                allowed_conversion_formats.remove(file.format.lower())
    if kepub_possible:
        allowed_conversion_formats.append('kepub')
    return render_title_template('book_edit.html', book=book, authors=author_names, cc=cc,
                                 title=_(u"edit metadata"), page="editbook",
                                 conversion_formats=allowed_conversion_formats,
                                 config=config,
                                 source_formats=valid_source_formats)


def edit_book_ratings(to_save, book):
    changed = False
    if to_save["rating"].strip():
        old_rating = False
        if len(book.ratings) > 0:
            old_rating = book.ratings[0].rating
        ratingx2 = int(float(to_save["rating"]) * 2)
        if ratingx2 != old_rating:
            changed = True
            is_rating = calibre_db.session.query(db.Ratings).filter(db.Ratings.rating == ratingx2).first()
            if is_rating:
                book.ratings.append(is_rating)
            else:
                new_rating = db.Ratings(rating=ratingx2)
                book.ratings.append(new_rating)
            if old_rating:
                book.ratings.remove(book.ratings[0])
    else:
        if len(book.ratings) > 0:
            book.ratings.remove(book.ratings[0])
            changed = True
    return changed

def edit_book_tags(tags, book):
    input_tags = tags.split(',')
    input_tags = list(map(lambda it: it.strip(), input_tags))
    # Remove duplicates
    input_tags = helper.uniq(input_tags)
    return modify_database_object(input_tags, book.tags, db.Tags, calibre_db.session, 'tags')


def edit_book_series(series, book):
    input_series = [series.strip()]
    input_series = [x for x in input_series if x != '']
    return modify_database_object(input_series, book.series, db.Series, calibre_db.session, 'series')


def edit_book_series_index(series_index, book):
    # Add default series_index to book
    modif_date = False
    series_index = series_index or '1'
    if book.series_index != series_index:
        book.series_index = series_index
        modif_date = True
    return modif_date

# Handle book comments/description
def edit_book_comments(comments, book):
    modif_date = False
    if len(book.comments):
        if book.comments[0].text != comments:
            book.comments[0].text = comments
            modif_date = True
    else:
        if comments:
            book.comments.append(db.Comments(text=comments, book=book.id))
            modif_date = True
    return modif_date


def edit_book_languages(languages, book, upload=False):
    input_languages = languages.split(',')
    unknown_languages = []
    if not upload:
        input_l = isoLanguages.get_language_codes(get_locale(), input_languages, unknown_languages)
    else:
        input_l = isoLanguages.get_valid_language_codes(get_locale(), input_languages, unknown_languages)
    for l in unknown_languages:
        log.error('%s is not a valid language', l)
        flash(_(u"%(langname)s is not a valid language", langname=l), category="warning")
    # ToDo: Not working correct
    if upload and len(input_l) == 1:
        # If the language of the file is excluded from the users view, it's not imported, to allow the user to view
        # the book it's language is set to the filter language
        if input_l[0] != current_user.filter_language() and current_user.filter_language() != "all":
            input_l[0] = calibre_db.session.query(db.Languages). \
                filter(db.Languages.lang_code == current_user.filter_language()).first()
    # Remove duplicates
    input_l = helper.uniq(input_l)
    return modify_database_object(input_l, book.languages, db.Languages, calibre_db.session, 'languages')


def edit_book_publisher(to_save, book):
    changed = False
    if to_save["publisher"]:
        publisher = to_save["publisher"].rstrip().strip()
        if len(book.publishers) == 0 or (len(book.publishers) > 0 and publisher != book.publishers[0].name):
            changed |= modify_database_object([publisher], book.publishers, db.Publishers, calibre_db.session,
                                              'publisher')
    elif len(book.publishers):
        changed |= modify_database_object([], book.publishers, db.Publishers, calibre_db.session, 'publisher')
    return changed


def edit_cc_data(book_id, book, to_save):
    changed = False
    cc = calibre_db.session.query(db.Custom_Columns).filter(db.Custom_Columns.datatype.notin_(db.cc_exceptions)).all()
    for c in cc:
        cc_string = "custom_column_" + str(c.id)
        if not c.is_multiple:
            if len(getattr(book, cc_string)) > 0:
                cc_db_value = getattr(book, cc_string)[0].value
            else:
                cc_db_value = None
            if to_save[cc_string].strip():
                if c.datatype == 'int' or c.datatype == 'bool' or c.datatype == 'float':
                    if to_save[cc_string] == 'None':
                        to_save[cc_string] = None
                    elif c.datatype == 'bool':
                        to_save[cc_string] = 1 if to_save[cc_string] == 'True' else 0

                    if to_save[cc_string] != cc_db_value:
                        if cc_db_value is not None:
                            if to_save[cc_string] is not None:
                                setattr(getattr(book, cc_string)[0], 'value', to_save[cc_string])
                                changed = True
                            else:
                                del_cc = getattr(book, cc_string)[0]
                                getattr(book, cc_string).remove(del_cc)
                                calibre_db.session.delete(del_cc)
                                changed = True
                        else:
                            cc_class = db.cc_classes[c.id]
                            new_cc = cc_class(value=to_save[cc_string], book=book_id)
                            calibre_db.session.add(new_cc)
                            changed = True

                else:
                    if c.datatype == 'rating':
                        to_save[cc_string] = str(int(float(to_save[cc_string]) * 2))
                    if to_save[cc_string].strip() != cc_db_value:
                        if cc_db_value is not None:
                            # remove old cc_val
                            del_cc = getattr(book, cc_string)[0]
                            getattr(book, cc_string).remove(del_cc)
                            if len(del_cc.books) == 0:
                                calibre_db.session.delete(del_cc)
                                changed = True
                        cc_class = db.cc_classes[c.id]
                        new_cc = calibre_db.session.query(cc_class).filter(
                            cc_class.value == to_save[cc_string].strip()).first()
                        # if no cc val is found add it
                        if new_cc is None:
                            new_cc = cc_class(value=to_save[cc_string].strip())
                            calibre_db.session.add(new_cc)
                            changed = True
                            calibre_db.session.flush()
                            new_cc = calibre_db.session.query(cc_class).filter(
                                cc_class.value == to_save[cc_string].strip()).first()
                        # add cc value to book
                        getattr(book, cc_string).append(new_cc)
            else:
                if cc_db_value is not None:
                    # remove old cc_val
                    del_cc = getattr(book, cc_string)[0]
                    getattr(book, cc_string).remove(del_cc)
                    if not del_cc.books or len(del_cc.books) == 0:
                        calibre_db.session.delete(del_cc)
                        changed = True
        else:
            input_tags = to_save[cc_string].split(',')
            input_tags = list(map(lambda it: it.strip(), input_tags))
            changed |= modify_database_object(input_tags,
                                              getattr(book, cc_string),
                                              db.cc_classes[c.id],
                                              calibre_db.session,
                                              'custom')
    return changed

def upload_single_file(request, book, book_id):
    # Check and handle Uploaded file
    if 'btn-upload-format' in request.files:
        requested_file = request.files['btn-upload-format']
        # check for empty request
        if requested_file.filename != '':
            if '.' in requested_file.filename:
                file_ext = requested_file.filename.rsplit('.', 1)[-1].lower()
                if file_ext not in constants.EXTENSIONS_UPLOAD and '' not in constants.EXTENSIONS_UPLOAD:
                    flash(_("File extension '%(ext)s' is not allowed to be uploaded to this server", ext=file_ext),
                          category="error")
                    return redirect(url_for('web.show_book', book_id=book.id))
            else:
                flash(_('File to be uploaded must have an extension'), category="error")
                return redirect(url_for('web.show_book', book_id=book.id))

            file_name = book.path.rsplit('/', 1)[-1]
            filepath = os.path.normpath(os.path.join(config.config_calibre_dir, book.path))
            saved_filename = os.path.join(filepath, file_name + '.' + file_ext)

            # check if file path exists, otherwise create it, copy file to calibre path and delete temp file
            if not os.path.exists(filepath):
                try:
                    os.makedirs(filepath)
                except OSError:
                    flash(_(u"Failed to create path %(path)s (Permission denied).", path=filepath), category="error")
                    return redirect(url_for('web.show_book', book_id=book.id))
            try:
                requested_file.save(saved_filename)
            except OSError:
                flash(_(u"Failed to store file %(file)s.", file=saved_filename), category="error")
                return redirect(url_for('web.show_book', book_id=book.id))

            file_size = os.path.getsize(saved_filename)
            is_format = calibre_db.get_book_format(book_id, file_ext.upper())

            # Format entry already exists, no need to update the database
            if is_format:
                log.warning('Book format %s already existing', file_ext.upper())
            else:
                try:
                    db_format = db.Data(book_id, file_ext.upper(), file_size, file_name)
                    calibre_db.session.add(db_format)
                    calibre_db.session.commit()
                    calibre_db.update_title_sort(config)
                except OperationalError as e:
                    calibre_db.session.rollback()
                    log.error('Database error: %s', e)
                    flash(_(u"Database error: %(error)s.", error=e), category="error")
                    return redirect(url_for('web.show_book', book_id=book.id))

            # Queue uploader info
            uploadText=_(u"File format %(ext)s added to %(book)s", ext=file_ext.upper(), book=book.title)
            worker.add_upload(current_user.nickname,
                "<a href=\"" + url_for('web.show_book', book_id=book.id) + "\">" + uploadText + "</a>")

            return uploader.process(
                saved_filename, *os.path.splitext(requested_file.filename),
                rarExecutable=config.config_rarfile_location)


def upload_cover(request, book):
    if 'btn-upload-cover' in request.files:
        requested_file = request.files['btn-upload-cover']
        # check for empty request
        if requested_file.filename != '':
            ret, message = helper.save_cover(requested_file, book.path)
            if ret is True:
                return True
            else:
                flash(message, category="error")
                return False
    return None


@editbook.route("/admin/book/<int:book_id>", methods=['GET', 'POST'])
@login_required_if_no_ano
@edit_required
def edit_book(book_id):
    modif_date = False
    # Show form
    if request.method != 'POST':
        return render_edit_book(book_id)

    # create the function for sorting...
    calibre_db.update_title_sort(config)
    book = calibre_db.get_filtered_book(book_id)

    # Book not found
    if not book:
        flash(_(u"Error opening eBook. File does not exist or file is not accessible"), category="error")
        return redirect(url_for("web.index"))

    meta = upload_single_file(request, book, book_id)
    if upload_cover(request, book) is True:
        book.has_cover = 1
        modif_date = True
    try:
        to_save = request.form.to_dict()
        merge_metadata(to_save, meta)
        # Update book
        edited_books_id = None
        #handle book title
        if book.title != to_save["book_title"].rstrip().strip():
            if to_save["book_title"] == '':
                to_save["book_title"] = _(u'Unknown')
            book.title = to_save["book_title"].rstrip().strip()
            edited_books_id = book.id
            modif_date = True

        # handle author(s)
        input_authors = to_save["author_name"].split('&')
        input_authors = list(map(lambda it: it.strip().replace(',', '|'), input_authors))
        # Remove duplicates in authors list
        input_authors = helper.uniq(input_authors)
        # we have all author names now
        if input_authors == ['']:
            input_authors = [_(u'Unknown')]  # prevent empty Author

        modif_date |= modify_database_object(input_authors, book.authors, db.Authors, calibre_db.session, 'author')

        # Search for each author if author is in database, if not, authorname and sorted authorname is generated new
        # everything then is assembled for sorted author field in database
        sort_authors_list = list()
        for inp in input_authors:
            stored_author = calibre_db.session.query(db.Authors).filter(db.Authors.name == inp).first()
            if not stored_author:
                stored_author = helper.get_sorted_author(inp)
            else:
                stored_author = stored_author.sort
            sort_authors_list.append(helper.get_sorted_author(stored_author))
        sort_authors = ' & '.join(sort_authors_list)
        if book.author_sort != sort_authors:
            edited_books_id = book.id
            book.author_sort = sort_authors
            modif_date = True

        if config.config_use_google_drive:
            gdriveutils.updateGdriveCalibreFromLocal()

        error = False
        if edited_books_id:
            error = helper.update_dir_stucture(edited_books_id, config.config_calibre_dir, input_authors[0])

        if not error:
            if to_save["cover_url"]:
                result, error = helper.save_cover_from_url(to_save["cover_url"], book.path)
                if result is True:
                    book.has_cover = 1
                    modif_date = True
                else:
                    flash(error, category="error")

            # Add default series_index to book
            modif_date |= edit_book_series_index(to_save["series_index"], book)

            # Handle book comments/description
            modif_date |= edit_book_comments(to_save["description"], book)

            # Handle identifiers
            input_identifiers = identifier_list(to_save, book)
            modification, warning = modify_identifiers(input_identifiers, book.identifiers, calibre_db.session)
            if warning:
                flash(_("Identifiers are not Case Sensitive, Overwriting Old Identifier"), category="warning")
            modif_date |= modification
            # Handle book tags
            modif_date |= edit_book_tags(to_save['tags'], book)

            # Handle book series
            modif_date |= edit_book_series(to_save["series"], book)

            if to_save["pubdate"]:
                try:
                    book.pubdate = datetime.strptime(to_save["pubdate"], "%Y-%m-%d")
                except ValueError:
                    book.pubdate = db.Books.DEFAULT_PUBDATE
            else:
                book.pubdate = db.Books.DEFAULT_PUBDATE

            # handle book publisher
            modif_date |= edit_book_publisher(to_save, book)

            # handle book languages
            modif_date |= edit_book_languages(to_save['languages'], book)

            # handle book ratings
            modif_date |= edit_book_ratings(to_save, book)

            # handle cc data
            modif_date |= edit_cc_data(book_id, book, to_save)

            if modif_date:
                book.last_modified = datetime.utcnow()
            calibre_db.session.merge(book)
            calibre_db.session.commit()
            if config.config_use_google_drive:
                gdriveutils.updateGdriveCalibreFromLocal()
            if "detail_view" in to_save:
                return redirect(url_for('web.show_book', book_id=book.id))
            else:
                flash(_("Metadata successfully updated"), category="success")
                return render_edit_book(book_id)
        else:
            calibre_db.session.rollback()
            flash(error, category="error")
            return render_edit_book(book_id)
    except Exception as e:
        log.exception(e)
        calibre_db.session.rollback()
        flash(_("Error editing book, please check logfile for details"), category="error")
        return redirect(url_for('web.show_book', book_id=book.id))


def merge_metadata(to_save, meta):
    if to_save['author_name'] == _(u'Unknown'):
        to_save['author_name'] = ''
    if to_save['book_title'] == _(u'Unknown'):
        to_save['book_title'] = ''
    for s_field, m_field in [
            ('tags', 'tags'), ('author_name', 'author'), ('series', 'series'),
            ('series_index', 'series_id'), ('languages', 'languages'),
            ('book_title', 'title')]:
        to_save[s_field] = to_save[s_field] or getattr(meta, m_field, '')
    to_save["description"] = to_save["description"] or Markup(
        getattr(meta, 'description', '')).unescape()

def identifier_list(to_save, book):
    """Generate a list of Identifiers from form information"""
    id_type_prefix = 'identifier-type-'
    id_val_prefix = 'identifier-val-'
    result = []
    for type_key, type_value in to_save.items():
        if not type_key.startswith(id_type_prefix):
            continue
        val_key = id_val_prefix + type_key[len(id_type_prefix):]
        if val_key not in to_save.keys():
            continue
        result.append(db.Identifiers(to_save[val_key], type_value, book.id))
    return result

@editbook.route("/upload", methods=["GET", "POST"])
@login_required_if_no_ano
@upload_required
def upload():
    if not config.config_uploading:
        abort(404)
    if request.method == 'POST' and 'btn-upload' in request.files:
        for requested_file in request.files.getlist("btn-upload"):
            try:
                modif_date = False
                # create the function for sorting...
                calibre_db.update_title_sort(config)
                calibre_db.session.connection().connection.connection.create_function('uuid4', 0, lambda: str(uuid4()))

                # check if file extension is correct
                if '.' in requested_file.filename:
                    file_ext = requested_file.filename.rsplit('.', 1)[-1].lower()
                    if file_ext not in constants.EXTENSIONS_UPLOAD and '' not in constants.EXTENSIONS_UPLOAD:
                        flash(
                            _("File extension '%(ext)s' is not allowed to be uploaded to this server",
                              ext=file_ext), category="error")
                        return Response(json.dumps({"location": url_for("web.index")}), mimetype='application/json')
                else:
                    flash(_('File to be uploaded must have an extension'), category="error")
                    return Response(json.dumps({"location": url_for("web.index")}), mimetype='application/json')

                # extract metadata from file
                try:
                    meta = uploader.upload(requested_file, config.config_rarfile_location)
                except (IOError, OSError):
                    log.error("File %s could not saved to temp dir", requested_file.filename)
                    flash(_(u"File %(filename)s could not saved to temp dir",
                            filename= requested_file.filename), category="error")
                    return Response(json.dumps({"location": url_for("web.index")}), mimetype='application/json')
                title = meta.title
                authr = meta.author

                if title != _(u'Unknown') and authr != _(u'Unknown'):
                    entry = calibre_db.check_exists_book(authr, title)
                    if entry:
                        log.info("Uploaded book probably exists in library")
                        flash(_(u"Uploaded book probably exists in the library, consider to change before upload new: ")
                            + Markup(render_title_template('book_exists_flash.html', entry=entry)), category="warning")

                # handle authors
                input_authors = authr.split('&')
                # handle_authors(input_authors)
                input_authors = list(map(lambda it: it.strip().replace(',', '|'), input_authors))
                # Remove duplicates in authors list
                input_authors = helper.uniq(input_authors)

                # we have all author names now
                if input_authors == ['']:
                    input_authors = [_(u'Unknown')]  # prevent empty Author

                sort_authors_list=list()
                db_author = None
                for inp in input_authors:
                    stored_author = calibre_db.session.query(db.Authors).filter(db.Authors.name == inp).first()
                    if not stored_author:
                        if not db_author:
                            db_author = db.Authors(inp, helper.get_sorted_author(inp), "")
                            calibre_db.session.add(db_author)
                            calibre_db.session.commit()
                        sort_author = helper.get_sorted_author(inp)
                    else:
                        if not db_author:
                            db_author = stored_author
                        sort_author = stored_author.sort
                    sort_authors_list.append(sort_author) # helper.get_sorted_author(sort_author))
                sort_authors = ' & '.join(sort_authors_list)

                title_dir = helper.get_valid_filename(title)
                author_dir = helper.get_valid_filename(db_author.name)
                filepath = os.path.join(config.config_calibre_dir, author_dir, title_dir)
                saved_filename = os.path.join(filepath, title_dir + meta.extension.lower())

                # check if file path exists, otherwise create it, copy file to calibre path and delete temp file
                if not os.path.exists(filepath):
                    try:
                        os.makedirs(filepath)
                    except OSError:
                        log.error("Failed to create path %s (Permission denied)", filepath)
                        flash(_(u"Failed to create path %(path)s (Permission denied).", path=filepath), category="error")
                        return Response(json.dumps({"location": url_for("web.index")}), mimetype='application/json')
                try:
                    copyfile(meta.file_path, saved_filename)
                    os.unlink(meta.file_path)
                except OSError as e:
                    log.error("Failed to move file %s: %s", saved_filename, e)
                    flash(_(u"Failed to Move File %(file)s: %(error)s", file=saved_filename, error=e), category="error")
                    return Response(json.dumps({"location": url_for("web.index")}), mimetype='application/json')

                if meta.cover is None:
                    has_cover = 0
                    copyfile(os.path.join(constants.STATIC_DIR, 'generic_cover.jpg'),
                             os.path.join(filepath, "cover.jpg"))
                else:
                    has_cover = 1

                # combine path and normalize path from windows systems
                path = os.path.join(author_dir, title_dir).replace('\\', '/')
                # Calibre adds books with utc as timezone
                db_book = db.Books(title, "", sort_authors, datetime.utcnow(), datetime(101, 1, 1),
                                   '1', datetime.utcnow(), path, has_cover, db_author, [], "")

                modif_date |= modify_database_object(input_authors, db_book.authors, db.Authors, calibre_db.session,
                                                     'author')

                # Add series_index to book
                modif_date |= edit_book_series_index(meta.series_id, db_book)

                # add languages
                modif_date |= edit_book_languages(meta.languages, db_book, upload=True)

                # handle tags
                modif_date |= edit_book_tags(meta.tags, db_book)

                # handle series
                modif_date |= edit_book_series(meta.series, db_book)

                # Add file to book
                file_size = os.path.getsize(saved_filename)
                db_data = db.Data(db_book, meta.extension.upper()[1:], file_size, title_dir)
                db_book.data.append(db_data)
                calibre_db.session.add(db_book)

                # flush content, get db_book.id available
                calibre_db.session.flush()

                # Comments needs book id therfore only possiblw after flush
                modif_date |= edit_book_comments(Markup(meta.description).unescape(), db_book)

                book_id = db_book.id
                title = db_book.title

                error = helper.update_dir_stucture(book_id, config.config_calibre_dir, input_authors[0])

                # move cover to final directory, including book id
                if has_cover:
                    new_coverpath = os.path.join(config.config_calibre_dir, db_book.path, "cover.jpg")
                    try:
                        copyfile(meta.cover, new_coverpath)
                        os.unlink(meta.cover)
                    except OSError as e:
                        log.error("Failed to move cover file %s: %s", new_coverpath, e)
                        flash(_(u"Failed to Move Cover File %(file)s: %(error)s", file=new_coverpath,
                                error=e),
                              category="error")

                # save data to database, reread data
                calibre_db.session.commit()
                #calibre_db.setup_db(config, ub.app_DB_path)
                # Reread book. It's important not to filter the result, as it could have language which hide it from
                # current users view (tags are not stored/extracted from metadata and could also be limited)
                #book = calibre_db.get_book(book_id)
                if config.config_use_google_drive:
                    gdriveutils.updateGdriveCalibreFromLocal()
                if error:
                    flash(error, category="error")
                uploadText=_(u"File %(file)s uploaded", file=title)
                worker.add_upload(current_user.nickname,
                    "<a href=\"" + url_for('web.show_book', book_id=book_id) + "\">" + uploadText + "</a>")

                if len(request.files.getlist("btn-upload")) < 2:
                    if current_user.role_edit() or current_user.role_admin():
                        resp = {"location": url_for('editbook.edit_book', book_id=book_id)}
                        return Response(json.dumps(resp), mimetype='application/json')
                    else:
                        resp = {"location": url_for('web.show_book', book_id=book_id)}
                        return Response(json.dumps(resp), mimetype='application/json')
            except OperationalError as e:
                calibre_db.session.rollback()
                log.error("Database error: %s", e)
                flash(_(u"Database error: %(error)s.", error=e), category="error")
        return Response(json.dumps({"location": url_for("web.index")}), mimetype='application/json')

@editbook.route("/admin/book/convert/<int:book_id>", methods=['POST'])
@login_required_if_no_ano
@edit_required
def convert_bookformat(book_id):
    # check to see if we have form fields to work with -  if not send user back
    book_format_from = request.form.get('book_format_from', None)
    book_format_to = request.form.get('book_format_to', None)

    if (book_format_from is None) or (book_format_to is None):
        flash(_(u"Source or destination format for conversion missing"), category="error")
        return redirect(url_for('editbook.edit_book', book_id=book_id))

    log.info('converting: book id: %s from: %s to: %s', book_id, book_format_from, book_format_to)
    rtn = helper.convert_book_format(book_id, config.config_calibre_dir, book_format_from.upper(),
                                     book_format_to.upper(), current_user.nickname)

    if rtn is None:
        flash(_(u"Book successfully queued for converting to %(book_format)s",
                    book_format=book_format_to),
                    category="success")
    else:
        flash(_(u"There was an error converting this book: %(res)s", res=rtn), category="error")
    return redirect(url_for('editbook.edit_book', book_id=book_id))