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

#  This file is part of the Calibre-Web (https://github.com/janeczku/calibre-web)
#    Copyright (C) 2020 pwr
#
#  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/>.

import os
import re
from glob import glob
from shutil import copyfile, copyfileobj
from markupsafe import escape
from time import time
from uuid import uuid4

from sqlalchemy.exc import SQLAlchemyError
from flask_babel import lazy_gettext as N_

from cps.services.worker import CalibreTask
from cps import db
from cps import logger, config
from cps.subproc_wrapper import process_open
from flask_babel import gettext as _
from cps.kobo_sync_status import remove_synced_book
from cps.ub import init_db_thread
from cps.file_helper import get_temp_dir

from cps.tasks.mail import TaskEmail
from cps import gdriveutils, helper
from cps.constants import SUPPORTED_CALIBRE_BINARIES

log = logger.create()

current_milli_time = lambda: int(round(time() * 1000))

class TaskConvert(CalibreTask):
    def __init__(self, file_path, book_id, task_message, settings, ereader_mail, user=None):
        super(TaskConvert, self).__init__(task_message)
        self.file_path = file_path
        self.book_id = book_id
        self.title = ""
        self.settings = settings
        self.ereader_mail = ereader_mail
        self.user = user

        self.results = dict()

    def run(self, worker_thread):
        self.worker_thread = worker_thread
        if config.config_use_google_drive:
            worker_db = db.CalibreDB(expire_on_commit=False, init=True)
            cur_book = worker_db.get_book(self.book_id)
            self.title = cur_book.title
            data = worker_db.get_book_format(self.book_id, self.settings['old_book_format'])
            df = gdriveutils.getFileFromEbooksFolder(cur_book.path,
                                                     data.name + "." + self.settings['old_book_format'].lower())
            df_cover = gdriveutils.getFileFromEbooksFolder(cur_book.path, "cover.jpg")
            if df:
                datafile = os.path.join(config.get_book_path(),
                                        cur_book.path,
                                        data.name + "." + self.settings['old_book_format'].lower())
                if df_cover:
                    datafile_cover = os.path.join(config.get_book_path(),
                                            cur_book.path, "cover.jpg")
                if not os.path.exists(os.path.join(config.get_book_path(), cur_book.path)):
                    os.makedirs(os.path.join(config.get_book_path(), cur_book.path))
                df.GetContentFile(datafile)
                if df_cover:
                    df_cover.GetContentFile(datafile_cover)
                worker_db.session.close()
            else:
                # ToDo Include cover in error handling
                error_message = _("%(format)s not found on Google Drive: %(fn)s",
                                  format=self.settings['old_book_format'],
                                  fn=data.name + "." + self.settings['old_book_format'].lower())
                worker_db.session.close()
                return self._handleError(self, error_message)

        filename = self._convert_ebook_format()
        if config.config_use_google_drive:
            os.remove(self.file_path + '.' + self.settings['old_book_format'].lower())
            if df_cover:
                os.remove(os.path.join(config.config_calibre_dir, cur_book.path, "cover.jpg"))

        if filename:
            if config.config_use_google_drive:
                # Upload files to gdrive
                gdriveutils.updateGdriveCalibreFromLocal()
                self._handleSuccess()
            if self.ereader_mail:
                # if we're sending to E-Reader after converting, create a one-off task and run it immediately
                # todo: figure out how to incorporate this into the progress
                try:
                    EmailText = N_("%(book)s send to E-Reader", book=escape(self.title))
                    worker_thread.add(self.user, TaskEmail(self.settings['subject'],
                                                           self.results["path"],
                                                           filename,
                                                           self.settings,
                                                           self.ereader_mail,
                                                           EmailText,
                                                           self.settings['body'],
                                                           id=self.book_id,
                                                           internal=True)
                                      )
                except Exception as ex:
                    return self._handleError(str(ex))

    def _convert_ebook_format(self):
        error_message = None
        local_db = db.CalibreDB(expire_on_commit=False, init=True)
        file_path = self.file_path
        book_id = self.book_id
        format_old_ext = '.' + self.settings['old_book_format'].lower()
        format_new_ext = '.' + self.settings['new_book_format'].lower()

        # check to see if destination format already exists - or if book is in database
        # if it does - mark the conversion task as complete and return a success
        # this will allow to send to E-Reader workflow to continue to work
        if os.path.isfile(file_path + format_new_ext) or\
                local_db.get_book_format(self.book_id, self.settings['new_book_format']):
            log.info("Book id %d already converted to %s", book_id, format_new_ext)
            cur_book = local_db.get_book(book_id)
            self.title = cur_book.title
            self.results['path'] = cur_book.path
            self.results['title'] = self.title
            new_format = local_db.session.query(db.Data).filter(db.Data.book == book_id)\
                .filter(db.Data.format == self.settings['new_book_format'].upper()).one_or_none()
            if not new_format:
                new_format = db.Data(name=os.path.basename(file_path),
                                     book_format=self.settings['new_book_format'].upper(),
                                     book=book_id, uncompressed_size=os.path.getsize(file_path + format_new_ext))
                try:
                    local_db.session.merge(new_format)
                    local_db.session.commit()
                except SQLAlchemyError as e:
                    local_db.session.rollback()
                    log.error("Database error: %s", e)
                    local_db.session.close()
                    self._handleError(N_("Oops! Database Error: %(error)s.", error=e))
                    return
                self._handleSuccess()
                local_db.session.close()
                return os.path.basename(file_path + format_new_ext)
        else:
            log.info("Book id %d - target format of %s does not exist. Moving forward with convert.",
                     book_id,
                     format_new_ext)

        if config.config_kepubifypath and format_old_ext == '.epub' and format_new_ext == '.kepub':
            check, error_message = self._convert_kepubify(file_path,
                                                          format_old_ext,
                                                          format_new_ext)
        else:
            # check if calibre converter-executable is existing
            if not os.path.exists(config.config_converterpath):
                self._handleError(N_("Calibre ebook-convert %(tool)s not found", tool=config.config_converterpath))
                return
            has_cover = local_db.get_book(book_id).has_cover
            check, error_message = self._convert_calibre(file_path, format_old_ext, format_new_ext, has_cover)

        if check == 0:
            cur_book = local_db.get_book(book_id)
            if os.path.isfile(file_path + format_new_ext):
                new_format = local_db.session.query(db.Data).filter(db.Data.book == book_id) \
                    .filter(db.Data.format == self.settings['new_book_format'].upper()).one_or_none()
                if not new_format:
                    new_format = db.Data(name=cur_book.data[0].name,
                                         book_format=self.settings['new_book_format'].upper(),
                                         book=book_id, uncompressed_size=os.path.getsize(file_path + format_new_ext))
                    try:
                        local_db.session.merge(new_format)
                        local_db.session.commit()
                        if self.settings['new_book_format'].upper() in ['KEPUB', 'EPUB', 'EPUB3']:
                            ub_session = init_db_thread()
                            remove_synced_book(book_id, True, ub_session)
                            ub_session.close()
                    except SQLAlchemyError as e:
                        local_db.session.rollback()
                        log.error("Database error: %s", e)
                        local_db.session.close()
                        self._handleError(error_message)
                        return
                self.results['path'] = cur_book.path
                self.title = cur_book.title
                self.results['title'] = self.title
                if not config.config_use_google_drive:
                    self._handleSuccess()
                return os.path.basename(file_path + format_new_ext)
            else:
                error_message = N_('%(format)s format not found on disk', format=format_new_ext.upper())
        local_db.session.close()
        log.info("ebook converter failed with error while converting book")
        if not error_message:
            error_message = N_('Ebook converter failed with unknown error')
        else:
            log.error(error_message)
        self._handleError(error_message)
        return

    def _convert_kepubify(self, file_path, format_old_ext, format_new_ext):
        if config.config_embed_metadata and config.config_binariesdir:
            tmp_dir, temp_file_name = helper.do_calibre_export(self.book_id, format_old_ext[1:])
            filename = os.path.join(tmp_dir, temp_file_name + format_old_ext)
            temp_file_path = tmp_dir
        else:
            filename = file_path + format_old_ext
            temp_file_path = os.path.dirname(file_path)
        quotes = [1, 3]
        command = [config.config_kepubifypath, filename, '-o', temp_file_path, '-i']
        try:
            p = process_open(command, quotes)
        except OSError as e:
            return 1, N_("Kepubify-converter failed: %(error)s", error=e)
        self.progress = 0.01
        while True:
            nextline = p.stdout.readlines()
            nextline = [x.strip('\n') for x in nextline if x != '\n']
            for line in nextline:
                log.debug(line)
            if p.poll() is not None:
                break

        # process returncode
        check = p.returncode

        # move file
        if check == 0:
            converted_file = glob(os.path.splitext(filename)[0] + "*.kepub.epub")
            if len(converted_file) == 1:
                copyfile(converted_file[0], (file_path + format_new_ext))
                os.unlink(converted_file[0])
            else:
                return 1, N_("Converted file not found or more than one file in folder %(folder)s",
                            folder=os.path.dirname(file_path))
        return check, None

    def _convert_calibre(self, file_path, format_old_ext, format_new_ext, has_cover):
        try:
            # path_tmp_opf = self._embed_metadata()
            if config.config_embed_metadata:
                quotes = [3, 5]
                tmp_dir = get_temp_dir()
                calibredb_binarypath = os.path.join(config.config_binariesdir, SUPPORTED_CALIBRE_BINARIES["calibredb"])
                my_env = os.environ.copy()
                if config.config_calibre_split:
                    my_env['CALIBRE_OVERRIDE_DATABASE_PATH'] = os.path.join(config.config_calibre_dir, "metadata.db")
                    library_path = config.config_calibre_split_dir
                else:
                    library_path = config.config_calibre_dir

                opf_command = [calibredb_binarypath, 'show_metadata', '--as-opf', str(self.book_id),
                               '--with-library', library_path]
                p = process_open(opf_command, quotes, my_env)
                p.wait()
                path_tmp_opf = os.path.join(tmp_dir, "metadata_" + str(uuid4()) + ".opf")
                with open(path_tmp_opf, 'w') as fd:
                    copyfileobj(p.stdout, fd)

            quotes = [1, 2, 4, 6]
            command = [config.config_converterpath, (file_path + format_old_ext),
                       (file_path + format_new_ext)]
            if config.config_embed_metadata:
                command.extend(['--from-opf', path_tmp_opf])
            if has_cover:
                command.extend(['--cover', os.path.join(os.path.dirname(file_path), 'cover.jpg')])
            quotes_index = 3
            if config.config_calibre:
                parameters = config.config_calibre.split(" ")
                for param in parameters:
                    command.append(param)
                    quotes.append(quotes_index)
                    quotes_index += 1

            p = process_open(command, quotes, newlines=False)
        except OSError as e:
            return 1, N_("Ebook-converter failed: %(error)s", error=e)

        while p.poll() is None:
            nextline = p.stdout.readline()
            if isinstance(nextline, bytes):
                nextline = nextline.decode('utf-8', errors="ignore").strip('\r\n')
            if nextline:
                log.debug(nextline)
            # parse progress string from calibre-converter
            progress = re.search(r"(\d+)%\s.*", nextline)
            if progress:
                self.progress = int(progress.group(1)) / 100
                if config.config_use_google_drive:
                    self.progress *= 0.9

        # process returncode
        check = p.returncode
        calibre_traceback = p.stderr.readlines()
        error_message = ""
        for ele in calibre_traceback:
            ele = ele.decode('utf-8', errors="ignore").strip('\n')
            log.debug(ele)
            if not ele.startswith('Traceback') and not ele.startswith('  File'):
                error_message = N_("Calibre failed with error: %(error)s", error=ele)
        return check, error_message

    @property
    def name(self):
        return N_("Convert")

    def __str__(self):
        if self.ereader_mail:
            return "Convert Book {} and mail it to {}".format(self.book_id, self.ereader_mail)
        else:
            return "Convert Book {}".format(self.book_id)

    @property
    def is_cancellable(self):
        return False