"""
Courseware page.
"""

import re

from bok_choy.page_object import PageObject, unguarded
from bok_choy.promise import EmptyPromise
from selenium.webdriver.common.action_chains import ActionChains

from common.test.acceptance.pages.lms.bookmarks import BookmarksPage
from common.test.acceptance.pages.lms.course_page import CoursePage


class CoursewarePage(CoursePage):
    """
    Course info.
    """

    url_path = "courseware/"
    xblock_component_selector = '.vert .xblock'

    # TODO: TNL-6546: Remove sidebar selectors
    section_selector = '.chapter'
    subsection_selector = '.chapter-content-container a'

    def __init__(self, browser, course_id):
        super(CoursewarePage, self).__init__(browser, course_id)
        self.nav = CourseNavPage(browser, self)

    def is_browser_on_page(self):
        return self.q(css='.course-content').present

    # TODO: TNL-6546: Remove and find callers
    @property
    def chapter_count_in_navigation(self):
        """
        Returns count of chapters available on LHS navigation.
        """
        return len(self.q(css='nav.course-navigation a.chapter'))

    # TODO: TNL-6546: Remove and find callers.
    @property
    def num_sections(self):
        """
        Return the number of sections in the sidebar on the page
        """
        return len(self.q(css=self.section_selector))

    # TODO: TNL-6546: Remove and find callers.
    @property
    def num_subsections(self):
        """
        Return the number of subsections in the sidebar on the page, including in collapsed sections
        """
        return len(self.q(css=self.subsection_selector))

    @property
    def xblock_components(self):
        """
        Return the xblock components within the unit on the page.
        """
        return self.q(css=self.xblock_component_selector)

    @property
    def num_xblock_components(self):
        """
        Return the number of rendered xblocks within the unit on the page
        """
        return len(self.xblock_components)

    def xblock_component_type(self, index=0):
        """
        Extract rendered xblock component type.

        Returns:
            str: xblock module type
            index: which xblock to query, where the index is the vertical display within the page
                (default is 0)
        """
        return self.q(css=self.xblock_component_selector).attrs('data-block-type')[index]

    def xblock_component_html_content(self, index=0):
        """
        Extract rendered xblock component html content.

        Returns:
            str: xblock module html content
            index: which xblock to query, where the index is the vertical display within the page
                (default is 0)

        """
        # When Student Notes feature is enabled, it looks for the content inside
        # `.edx-notes-wrapper-content` element (Otherwise, you will get an
        # additional html related to Student Notes).
        element = self.q(css='{} .edx-notes-wrapper-content'.format(self.xblock_component_selector))
        if element.first:
            return element.attrs('innerHTML')[index].strip()
        else:
            return self.q(css=self.xblock_component_selector).attrs('innerHTML')[index].strip()

    def verify_tooltips_displayed(self):
        """
        Verify that all sequence navigation bar tooltips are being displayed upon mouse hover.

        If a tooltip does not appear, raise a BrokenPromise.
        """
        for index, tab in enumerate(self.q(css='#sequence-list > li')):
            ActionChains(self.browser).move_to_element(tab).perform()
            self.wait_for_element_visibility(
                '#tab_{index} > .sequence-tooltip'.format(index=index),
                'Tab {index} should appear'.format(index=index)
            )

    @property
    def course_license(self):
        """
        Returns the course license text, if present. Else returns None.
        """
        element = self.q(css="#content .container-footer .course-license")
        if element.is_present():
            return element.text[0]
        return None

    def go_to_sequential_position(self, sequential_position):
        """
        Within a section/subsection navigate to the sequential position specified by `sequential_position`.

        Arguments:
            sequential_position (int): position in sequential bar
        """
        def is_at_new_position():
            """
            Returns whether the specified tab has become active. It is defensive
            against the case where the page is still being loaded.
            """
            active_tab = self._active_sequence_tab
            try:
                return active_tab and int(active_tab.attrs('data-element')[0]) == sequential_position
            except IndexError:
                return False

        sequential_position_css = '#sequence-list #tab_{0}'.format(sequential_position - 1)
        self.q(css=sequential_position_css).first.click()
        EmptyPromise(is_at_new_position, "Position navigation fulfilled").fulfill()

    @property
    def sequential_position(self):
        """
        Returns the position of the active tab in the sequence.
        """
        tab_id = self._active_sequence_tab.attrs('id')[0]
        return int(tab_id.split('_')[1])

    @property
    def _active_sequence_tab(self):  # pylint: disable=missing-docstring
        return self.q(css='#sequence-list .nav-item.active')

    @property
    def is_next_button_enabled(self):  # pylint: disable=missing-docstring
        return not self.q(css='.sequence-nav > .sequence-nav-button.button-next.disabled').is_present()

    @property
    def is_previous_button_enabled(self):  # pylint: disable=missing-docstring
        return not self.q(css='.sequence-nav > .sequence-nav-button.button-previous.disabled').is_present()

    def click_next_button_on_top(self):  # pylint: disable=missing-docstring
        self._click_navigation_button('sequence-nav', 'button-next')

    def click_next_button_on_bottom(self):  # pylint: disable=missing-docstring
        self._click_navigation_button('sequence-bottom', 'button-next')

    def click_previous_button_on_top(self):  # pylint: disable=missing-docstring
        self._click_navigation_button('sequence-nav', 'button-previous')

    def click_previous_button_on_bottom(self):  # pylint: disable=missing-docstring
        self._click_navigation_button('sequence-bottom', 'button-previous')

    def _click_navigation_button(self, top_or_bottom_class, next_or_previous_class):
        """
        Clicks the navigation button, given the respective CSS classes.
        """
        previous_tab_id = self._active_sequence_tab.attrs('data-id')[0]

        def is_at_new_tab_id():
            """
            Returns whether the active tab has changed. It is defensive
            against the case where the page is still being loaded.
            """
            active_tab = self._active_sequence_tab
            try:
                return active_tab and previous_tab_id != active_tab.attrs('data-id')[0]
            except IndexError:
                return False

        self.q(
            css='.{} > .sequence-nav-button.{}'.format(top_or_bottom_class, next_or_previous_class)
        ).first.click()
        EmptyPromise(is_at_new_tab_id, "Button navigation fulfilled").fulfill()

    @property
    def can_start_proctored_exam(self):
        """
        Returns True if the timed/proctored exam timer bar is visible on the courseware.
        """
        return self.q(css='button.start-timed-exam[data-start-immediately="false"]').is_present()

    def start_timed_exam(self):
        """
        clicks the start this timed exam link
        """
        self.q(css=".xblock-student_view .timed-exam .start-timed-exam").first.click()
        self.wait_for_element_presence(".proctored_exam_status .exam-timer", "Timer bar")

    def stop_timed_exam(self):
        """
        clicks the stop this timed exam link
        """
        self.q(css=".proctored_exam_status button.exam-button-turn-in-exam").first.click()
        self.wait_for_element_absence(".proctored_exam_status .exam-button-turn-in-exam", "End Exam Button gone")
        self.wait_for_element_presence("button[name='submit-proctored-exam']", "Submit Exam Button")
        self.q(css="button[name='submit-proctored-exam']").first.click()
        self.wait_for_element_absence(".proctored_exam_status .exam-timer", "Timer bar")

    def start_proctored_exam(self):
        """
        clicks the start this timed exam link
        """
        self.q(css='button.start-timed-exam[data-start-immediately="false"]').first.click()

        # Wait for the unique exam code to appear.
        # self.wait_for_element_presence(".proctored-exam-code", "unique exam code")

    def has_submitted_exam_message(self):
        """
        Returns whether the "you have submitted your exam" message is present.
        This being true implies "the exam contents and results are hidden".
        """
        return self.q(css="div.proctored-exam.completed").visible

    def content_hidden_past_due_date(self):
        """
        Returns whether the "the due date for this ___ has passed" message is present.
        ___ is the type of the hidden content, and defaults to subsection.
        This being true implies "the ___ contents are hidden because their due date has passed".
        """
        message = "this assignment is no longer available"
        if self.q(css="div.seq_content").is_present():
            return False
        for html in self.q(css="div.hidden-content").html:
            if message in html:
                return True
        return False

    @property
    def entrance_exam_message_selector(self):
        """
        Return the entrance exam status message selector on the top of courseware page.
        """
        return self.q(css='#content .container section.course-content .sequential-status-message')

    def has_entrance_exam_message(self):
        """
        Returns boolean indicating presence entrance exam status message container div.
        """
        return self.entrance_exam_message_selector.is_present()

    def has_passed_message(self):
        """
        Returns boolean indicating presence of passed message.
        """
        return self.entrance_exam_message_selector.is_present() \
            and "You have passed the entrance exam" in self.entrance_exam_message_selector.text[0]

    def has_banner(self):
        """
        Returns boolean indicating presence of banner
        """
        return self.q(css='.pattern-library-shim').is_present()

    @property
    def is_timer_bar_present(self):
        """
        Returns True if the timed/proctored exam timer bar is visible on the courseware.
        """
        return self.q(css=".proctored_exam_status .exam-timer").is_present()

    def active_usage_id(self):
        """ Returns the usage id of active sequence item """
        get_active = lambda el: 'active' in el.get_attribute('class')
        attribute_value = lambda el: el.get_attribute('data-id')
        return self.q(css='#sequence-list .nav-item').filter(get_active).map(attribute_value).results[0]

    def unit_title_visible(self):
        """ Check if unit title is visible """
        return self.q(css='.unit-title').visible

    def bookmark_button_visible(self):
        """ Check if bookmark button is visible """
        EmptyPromise(lambda: self.q(css='.bookmark-button').visible, "Bookmark button visible").fulfill()
        return True

    @property
    def bookmark_button_state(self):
        """ Return `bookmarked` if button is in bookmarked state else '' """
        return 'bookmarked' if self.q(css='.bookmark-button.bookmarked').present else ''

    @property
    def bookmark_icon_visible(self):
        """ Check if bookmark icon is visible on active sequence nav item """
        return self.q(css='.active .bookmark-icon').visible

    def click_bookmark_unit_button(self):
        """ Bookmark a unit by clicking on Bookmark button """
        previous_state = self.bookmark_button_state
        self.q(css='.bookmark-button').first.click()
        EmptyPromise(lambda: self.bookmark_button_state != previous_state, "Bookmark button toggled").fulfill()

    # TODO: TNL-6546: Remove this helper function
    def click_bookmarks_button(self):
        """ Click on Bookmarks button """
        self.q(css='.bookmarks-list-button').first.click()
        bookmarks_page = BookmarksPage(self.browser, self.course_id)
        bookmarks_page.visit()


class CoursewareSequentialTabPage(CoursePage):
    """
    Courseware Sequential page
    """

    def __init__(self, browser, course_id, chapter, subsection, position):
        super(CoursewareSequentialTabPage, self).__init__(browser, course_id)
        self.url_path = "courseware/{}/{}/{}".format(chapter, subsection, position)

    def is_browser_on_page(self):
        return self.q(css='nav.sequence-list-wrapper').present

    def get_selected_tab_content(self):
        """
        return the body of the sequential currently selected
        """
        return self.q(css='#seq_content .xblock').text[0]


class CourseNavPage(PageObject):
    """
    Handles navigation on the courseware pages, including sequence navigation and
    breadcrumbs.
    """

    url = None

    def __init__(self, browser, parent_page):
        super(CourseNavPage, self).__init__(browser)
        self.parent_page = parent_page
        # TODO: TNL-6546: Remove the following
        self.unified_course_view = False

    def is_browser_on_page(self):
        return self.parent_page.is_browser_on_page

    @property
    def breadcrumb_section_title(self):
        """
        Returns the section's title from the breadcrumb, or None if one is not found.
        """
        label = self.q(css='.breadcrumbs .nav-item-chapter').text
        return label[0].strip() if label else None

    @property
    def breadcrumb_subsection_title(self):
        """
        Returns the subsection's title from the breadcrumb, or None if one is not found
        """
        label = self.q(css='.breadcrumbs .nav-item-section').text
        return label[0].strip() if label else None

    @property
    def breadcrumb_unit_title(self):
        """
        Returns the unit's title from the breadcrumb, or None if one is not found
        """
        label = self.q(css='.breadcrumbs .nav-item-sequence').text
        return label[0].strip() if label else None

    # TODO: TNL-6546: Remove method, outline no longer on courseware page
    @property
    def sections(self):
        """
        Return a dictionary representation of sections and subsections.

        Example:

            {
                'Introduction': ['Course Overview'],
                'Week 1': ['Lesson 1', 'Lesson 2', 'Homework']
                'Final Exam': ['Final Exam']
            }

        You can use these titles in `go_to_section` to navigate to the section.
        """
        # Dict to store the result
        nav_dict = dict()

        section_titles = self._section_titles()

        # Get the section titles for each chapter
        for sec_index, sec_title in enumerate(section_titles):

            if len(section_titles) < 1:
                self.warning("Could not find subsections for '{0}'".format(sec_title))
            else:
                # Add one to convert list index (starts at 0) to CSS index (starts at 1)
                nav_dict[sec_title] = self._subsection_titles(sec_index + 1)

        return nav_dict

    @property
    def sequence_items(self):
        """
        Return a list of sequence items on the page.
        Sequence items are one level below subsections in the course nav.

        Example return value:
            ['Chemical Bonds Video', 'Practice Problems', 'Homework']
        """
        seq_css = 'ol#sequence-list>li>.nav-item>.sequence-tooltip'
        return self.q(css=seq_css).map(self._clean_seq_titles).results

    # TODO: TNL-6546: Remove method, outline no longer on courseware page
    def go_to_section(self, section_title, subsection_title):
        """
        Go to the section in the courseware.
        Every section must have at least one subsection, so specify
        both the section and subsection title.

        Example:
            go_to_section("Week 1", "Lesson 1")
        """

        # For test stability, disable JQuery animations (opening / closing menus)
        self.browser.execute_script("jQuery.fx.off = true;")

        # Get the section by index
        try:
            sec_index = self._section_titles().index(section_title)
        except ValueError:
            self.warning("Could not find section '{0}'".format(section_title))
            return

        # Click the section to ensure it's open (no harm in clicking twice if it's already open)
        # Add one to convert from list index to CSS index
        section_css = '.course-navigation .chapter:nth-of-type({0})'.format(sec_index + 1)
        self.q(css=section_css).first.click()

        # Get the subsection by index
        try:
            subsec_index = self._subsection_titles(sec_index + 1).index(subsection_title)
        except ValueError:
            msg = "Could not find subsection '{0}' in section '{1}'".format(subsection_title, section_title)
            self.warning(msg)
            return

        # Convert list indices (start at zero) to CSS indices (start at 1)
        subsection_css = (
            ".course-navigation .chapter-content-container:nth-of-type({0}) "
            ".menu-item:nth-of-type({1})"
        ).format(sec_index + 1, subsec_index + 1)

        # Click the subsection and ensure that the page finishes reloading
        self.q(css=subsection_css).first.click()
        self._on_section_promise(section_title, subsection_title).fulfill()

    def go_to_vertical(self, vertical_title):
        """
        Within a section/subsection, navigate to the vertical with `vertical_title`.
        """

        # Get the index of the item in the sequence
        all_items = self.sequence_items

        try:
            seq_index = all_items.index(vertical_title)

        except ValueError:
            msg = "Could not find sequential '{0}'.  Available sequentials: [{1}]".format(
                vertical_title, ", ".join(all_items)
            )
            self.warning(msg)

        else:

            # Click on the sequence item at the correct index
            # Convert the list index (starts at 0) to a CSS index (starts at 1)
            seq_css = "ol#sequence-list>li:nth-of-type({0})>.nav-item".format(seq_index + 1)
            self.q(css=seq_css).first.click()
            # Click triggers an ajax event
            self.wait_for_ajax()

    # TODO: TNL-6546: Remove method, outline no longer on courseware page
    def _section_titles(self):
        """
        Return a list of all section titles on the page.
        """
        chapter_css = '.course-navigation .chapter .group-heading'
        return self.q(css=chapter_css).map(lambda el: el.text.strip()).results

    # TODO: TNL-6546: Remove method, outline no longer on courseware page
    def _subsection_titles(self, section_index):
        """
        Return a list of all subsection titles on the page
        for the section at index `section_index` (starts at 1).
        """
        # Retrieve the subsection title for the section
        # Add one to the list index to get the CSS index, which starts at one
        subsection_css = (
            ".course-navigation .chapter-content-container:nth-of-type({0}) "
            ".menu-item a p:nth-of-type(1)"
        ).format(section_index)

        # If the element is visible, we can get its text directly
        # Otherwise, we need to get the HTML
        # It *would* make sense to always get the HTML, but unfortunately
        # the open tab has some child <span> tags that we don't want.
        return self.q(
            css=subsection_css
        ).map(
            lambda el: el.text.strip().split('\n')[0] if el.is_displayed() else el.get_attribute('innerHTML').strip()
        ).results

    # TODO: TNL-6546: Remove method, outline no longer on courseware page
    def _on_section_promise(self, section_title, subsection_title):
        """
        Return a `Promise` that is fulfilled when the user is on
        the correct section and subsection.
        """
        desc = "currently at section '{0}' and subsection '{1}'".format(section_title, subsection_title)
        return EmptyPromise(
            lambda: self.is_on_section(section_title, subsection_title), desc
        )

    def go_to_outline(self):
        """
        Navigates using breadcrumb to the course outline on the course home page.

        Returns CourseHomePage page object.
        """
        # To avoid circular dependency, importing inside the function
        from common.test.acceptance.pages.lms.course_home import CourseHomePage

        course_home_page = CourseHomePage(self.browser, self.parent_page.course_id)
        self.q(css='.nav-item-course').click()
        course_home_page.wait_for_page()
        return course_home_page

    @unguarded
    def is_on_section(self, section_title, subsection_title):
        """
        Return a boolean indicating whether the user is on the section and subsection
        with the specified titles.
        """
        return self.breadcrumb_section_title == section_title and self.breadcrumb_subsection_title == subsection_title

    # Regular expression to remove HTML span tags from a string
    REMOVE_SPAN_TAG_RE = re.compile(r'</span>(.+)<span')

    def _clean_seq_titles(self, element):
        """
        Clean HTML of sequence titles, stripping out span tags and returning the first line.
        """
        return self.REMOVE_SPAN_TAG_RE.search(element.get_attribute('innerHTML')).groups()[0].strip()

    # TODO: TNL-6546: Remove. This is no longer needed.
    @property
    def active_subsection_url(self):
        """
        return the url of the active subsection in the left nav
        """
        return self.q(css='.chapter-content-container .menu-item.active a').attrs('href')[0]

    # TODO: TNL-6546: Remove all references to self.unified_course_view
    # TODO: TNL-6546: Remove the following function
    def visit_unified_course_view(self):
        # use unified_course_view version of the nav
        self.unified_course_view = True
        # reload the same page with the unified course view
        self.browser.get(self.browser.current_url + "&unified_course_view=1")
        self.wait_for_page()
