# This file is part of EbookLib.
# Copyright (c) 2013 Aleksandar Erkalovic <aerkalov@gmail.com>
#
# EbookLib is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# EbookLib 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with EbookLib.  If not, see <http://www.gnu.org/licenses/>.

import io
import mimetypes
import os

from lxml import etree

mimetype_initialised = False


def debug(obj):
    import pprint

    pp = pprint.PrettyPrinter(indent=4)
    pp.pprint(obj)


def parse_string(s):
    parser = etree.XMLParser(recover=True, resolve_entities=False)
    try:
        tree = etree.parse(io.BytesIO(s.encode("utf-8")), parser=parser)
    except Exception:
        tree = etree.parse(io.BytesIO(s), parser=parser)

    return tree


def parse_html_string(s):
    from lxml import html

    utf8_parser = html.HTMLParser(encoding="utf-8")

    html_tree = html.document_fromstring(s, parser=utf8_parser)

    return html_tree


def guess_type(extenstion):
    global mimetype_initialised

    if not mimetype_initialised:
        mimetypes.init()
        mimetypes.add_type("application/xhtml+xml", ".xhtml")
        mimetype_initialised = True

    return mimetypes.guess_type(extenstion)


def create_pagebreak(pageref, label=None, html=True):
    from ebooklib.epub import NAMESPACES

    pageref_attributes = {
        "{%s}type" % NAMESPACES["EPUB"]: "pagebreak",  # noqa
        "title": "{pageref}".format(pageref=pageref),  # noqa: UP032
        "id": "{pageref}".format(pageref=pageref),  # noqa: UP032
    }

    pageref_elem = etree.Element("span", pageref_attributes, nsmap={"epub": NAMESPACES["EPUB"]})

    if label:
        pageref_elem.text = label

    if html:
        return etree.tostring(pageref_elem, encoding="unicode")

    return pageref_elem


def get_headers(elem):
    for n in range(1, 7):
        headers = elem.xpath("./h{n}".format(n=n))  # noqa: UP032

        if len(headers) > 0:
            text = headers[0].text_content().strip()
            if len(text) > 0:
                return text
    return None


def get_pages(item):
    body = parse_html_string(item.get_body_content())
    pages = []

    for elem in body.iter():
        if "epub:type" in elem.attrib:
            if elem.get("id") is not None:
                _text = None

                if elem.text is not None and elem.text.strip() != "":
                    _text = elem.text.strip()

                if _text is None:
                    _text = elem.get("aria-label")

                if _text is None:
                    _text = get_headers(elem)

                pages.append((item.get_name(), elem.get("id"), _text or elem.get("id")))

    return pages


def get_pages_for_items(items):
    pages_from_docs = [get_pages(item) for item in items]

    return [item for pages in pages_from_docs for item in pages]


class Directory(object):  # noqa: UP004
    def __init__(self, directory_path):
        self.directory_path = directory_path

    def read(self, subname):
        with open(os.path.join(self.directory_path, subname), "rb") as fp:
            return fp.read()

    def close(self):
        pass