from browser import document, window, DOMNode
from js_modules.swiper import Swiper
from template import Template


class SlideShow:

    def __init__(self):
        self.swiper = None
        slideshow_tpl = Template('photo/slideshow.html')
        self.slideshow_elt = slideshow_tpl.get_elt()
        self.comments_count_elt = self.slideshow_elt.select_one('.comments__count')
        self.wrapper = self.slideshow_elt.select_one(".swiper-wrapper")
        self.hidden_elts = {}

    @property
    def current_slide(self):
        if self.swiper is None:
            return None
        try:
            return DOMNode(self.swiper.slides[self.swiper.realIndex])
        # getting missing item in JS arrays returns KeyError
        except KeyError:
            return None

    @property
    def current_item(self):
        """item attached to the current slide, if any"""
        current = self.current_slide
        if current is None:
            return
        try:
            return current.js._item
        except AttributeError:
            return None

    @property
    def index(self):
        if self.swiper is None:
            return None
        return self.swiper.realIndex

    @index.setter
    def index(self, idx):
        if self.swiper is not None:
            self.swiper.slideTo(idx, 0)

    def attach(self):
        # we hide other elts to avoid scrolling issues
        for elt in document.body.children:
            self.hidden_elts[elt] = elt.style.display
            elt.style.display = "none"
        document.body <= self.slideshow_elt
        self.swiper = Swiper.new(
            ".swiper-container",
            {
                "pagination": {
                    "el": ".swiper-pagination",
                },
                "navigation": {
                    "nextEl": ".swiper-button-next",
                    "prevEl": ".swiper-button-prev",
                    "hideOnClick": True,
                },
                "scrollbar": {
                    "el": ".swiper-scrollbar",
                },
                "grabCursor": True,
                "keyboard": {
                    "enabled": True,
                    "onlyInViewport": False,
                },
                "mousewheel": True,
            }
        )
        window.addEventListener("keydown", self.on_key_down, True)
        self.slideshow_elt.select_one(".click_to_close").bind("click", self.on_close)
        self.slideshow_elt.select_one(".click_to_comment").bind("click", self.on_comment)
        self.swiper.on("slideChange", self.on_slide_change)
        self.on_slide_change()

    def add_slide(self, slide_elt):
        self.swiper.appendSlide([slide_elt])
        self.swiper.update()

    def quit(self):
        # we unhide
        for elt, display in self.hidden_elts.items():
            elt.style.display = display
        self.hidden_elts.clear()
        self.slideshow_elt.remove()
        self.slideshow_elt = None
        self.swiper.destroy(True, True)
        self.swiper = None

    def on_key_down(self, evt):
        if evt.key == 'Escape':
            self.quit()
        else:
            return
        evt.preventDefault()

    def on_slide_change(self):
        item = self.current_item
        if item is None:
            return
        comments_count = item.get('comments_count')
        self.comments_count_elt.text = comments_count or ''

    def on_close(self, evt):
        evt.stopPropagation()
        evt.preventDefault()
        self.quit()

    def on_comment_close(self, evt):
        side_panel = self.comments_panel_elt.select_one('.comments_side_panel')
        side_panel.classList.remove('open')
        side_panel.bind("transitionend", lambda evt: self.comments_panel_elt.remove())

    def on_comments_panel_click(self, evt):
        # we stop stop propagation to avoid the closing of the panel
        evt.stopPropagation()

    def on_comment(self, evt):
        item = self.current_item
        if item is None:
            return
        comments_panel_tpl = Template('blog/comments_panel.html')
        try:
            comments = item['comments']['items']
        except KeyError:
            comments = []
        self.comments_panel_elt = comments_panel_tpl.get_elt({
            "comments": comments,
            "comments_service": item['comments_service'],
            "comments_node": item['comments_node'],

        })
        self.slideshow_elt <= self.comments_panel_elt
        side_panel = self.comments_panel_elt.select_one('.comments_side_panel')
        window.setTimeout(lambda: side_panel.classList.add("open"))
        for close_elt in self.comments_panel_elt.select('.click_to_close'):
             close_elt.bind("click", self.on_comment_close)
        side_panel.bind("click", self.on_comments_panel_click)