from collections import OrderedDict
from os import listdir, path

from django.db.models import Count, Q, F, Max, ExpressionWrapper, Prefetch
from django.utils.http import urlsafe_base64_encode

from .models import ComicBook, Directory, Setting


def generate_title_from_path(file_path):
    if file_path == "":
        return "CBWebReader"
    return "CBWebReader - " + " - ".join(file_path.split(path.sep))


class Menu:
    def __init__(self, user, page=""):
        """

        :type page: str
        """
        self.menu_items = OrderedDict()
        self.menu_items["Browse"] = "/comic/"
        self.menu_items["Recent"] = "/comic/recent/"
        self.menu_items["Account"] = "/comic/account/"
        if user.is_superuser:
            self.menu_items["Settings"] = "/comic/settings/"
            self.menu_items["Users"] = "/comic/settings/users/"
        self.menu_items["Logout"] = "/logout/"
        self.current_page = page


class Breadcrumb:
    def __init__(self):
        self.name = "Home"
        self.url = "/comic/"

    def __str__(self):
        return self.name

    def __unicode__(self):
        return self.name


def generate_breadcrumbs_from_path(directory=False, book=False):
    """

    :type directory: Directory
    :type book: ComicBook
    """
    output = [Breadcrumb()]
    if directory:
        folders = directory.get_path_objects()
    else:
        folders = []
    for item in folders[::-1]:
        bc = Breadcrumb()
        bc.name = item.name
        bc.url = "/comic/" + urlsafe_base64_encode(item.selector.bytes)
        output.append(bc)
    if book:
        bc = Breadcrumb()
        bc.name = book.file_name
        bc.url = "/read/" + urlsafe_base64_encode(book.selector.bytes)
        output.append(bc)

    return output


def generate_breadcrumbs_from_menu(paths):
    output = [Breadcrumb()]
    for item in paths:
        bc = Breadcrumb()
        bc.name = item[0]
        bc.url = item[1]
        output.append(bc)
    return output


class DirFile:
    def __init__(self):
        self.name = ""
        self.icon = ""
        self.location = ""
        self.label = ""
        self.type = ""
        self.selector = ""

    def __str__(self):
        return self.name

    def populate_directory(self, directory, user):
        self.name = directory.name
        self.icon = "fa-folder-open"
        self.selector = urlsafe_base64_encode(directory.selector.bytes)
        self.location = "/comic/{0}/".format(self.selector)
        self.label = generate_dir_status(directory.total, directory.total_read)
        self.type = "directory"

    def populate_comic(self, comic, user):
        if type(comic) == str:
            self.icon = "fa-exclamation-circle"
            self.name = comic
            self.selector = "0"
            self.location = "/"
            self.label = '<center><span class="label label-danger">Error</span></center>'
            self.type = "book"
        else:
            self.icon = "fa-book"
            self.name = comic.file_name
            self.selector = urlsafe_base64_encode(comic.selector.bytes)
            self.location = "/comic/read/{0}/".format(self.selector)
            self.label = generate_label(comic)
            self.type = "book"

    def __repr__(self):
        return f"<DirFile: {self.name}: {self.type}>"


def generate_directory(user, directory=False):
    """
    :type user: User
    :type directory: Directory
    """
    base_dir = Setting.objects.get(name="BASE_DIR").value
    files = []
    if directory:
        ordered_dir_list = listdir(path.join(base_dir, directory.path))
        dir_list = [x for x in ordered_dir_list if path.isdir(path.join(base_dir, directory.path, x))]
    else:
        ordered_dir_list = listdir(base_dir)
        dir_list = [x for x in ordered_dir_list if path.isdir(path.join(base_dir, x))]
    file_list = [x for x in ordered_dir_list if x not in dir_list]
    if directory:
        dir_list_obj = Directory.objects.filter(name__in=dir_list, parent=directory)
        file_list_obj = ComicBook.objects.filter(file_name__in=file_list, directory=directory)
    else:
        dir_list_obj = Directory.objects.filter(name__in=dir_list, parent__isnull=True)
        file_list_obj = ComicBook.objects.filter(file_name__in=file_list, directory__isnull=True)

    dir_list_obj = dir_list_obj.filter(comicbook__comicstatus__user=user).annotate(
        total=Count('comicbook'),
        total_read=Count('comicbook__comicstatus', Q(comicbook__comicstatus__finished=True))
    )
    file_list_obj = file_list_obj.filter(comicstatus__user=user).annotate(
        total_pages=Count('comicpage'),
        last_read_page=F('comicstatus__last_read_page'),
        finished=F('comicstatus__finished'),
        unread=F('comicstatus__unread')
    )

    for directory_obj in dir_list_obj:
        df = DirFile()
        df.populate_directory(directory_obj, user)
        files.append(df)
        dir_list.remove(directory_obj.name)

    for file_obj in file_list_obj:
        df = DirFile()
        df.populate_comic(file_obj, user)
        files.append(df)
        file_list.remove(file_obj.file_name)

    for directory_name in dir_list:
        if directory:
            directory_obj = Directory(name=directory_name, parent=directory)
        else:
            directory_obj = Directory(name=directory_name)
        directory_obj.save()
        directory_obj.total = 0
        directory_obj.total_read = 0
        df = DirFile()
        df.populate_directory(directory_obj, user)
        files.append(df)

    for file_name in file_list:
        if file_name.lower()[-4:] in [".rar", ".zip", ".cbr", ".cbz", ".pdf"]:
            book = ComicBook.process_comic_book(file_name, directory)
            df = DirFile()
            df.populate_comic(book, user)
            files.append(df)
    files.sort(key=lambda x: x.name)
    files.sort(key=lambda x: x.type, reverse=True)
    return files


def generate_label(book):
    """
    book need to be annotated with the following from ComicStatus
        * unread
        * finished
        * last_read_page
        * total_pages
    :param book: ComicBook
    :return: str
    """
    unread_text = '<center><span class="label label-default">Unread</span></center>'
    if not hasattr(book, 'unread'):
        label_text = unread_text
    elif book.unread or book.unread is None:
        label_text = unread_text
    elif book.finished:
        label_text = '<center><span class="label label-success">Read</span></center>'
    else:
        label_text = '<center><span class="label label-primary">%s/%s</span></center>' % (
            book.last_read_page + 1,
            book.total_pages,
        )
    return label_text


def generate_dir_status(total, total_read):
    if total == 0:
        return '<center><span class="label label-default">Empty</span></center>'
    elif total == total_read:
        return '<center><span class="label label-success">All Read</span></center>'
    elif total_read == 0:
        return '<center><span class="label label-default">Unread</span></center>'
    return f'<center><span class="label label-primary">{total_read}/{total}</span></center>'


def get_ordered_dir_list(folder):
    directories = []
    files = []
    for item in listdir(folder):
        if path.isdir(path.join(folder, item)):
            directories.append(item)
        else:
            files.append(item)
    return sorted(directories) + sorted(files)