from datetime import datetime

from PyQt5.QtWidgets import QAbstractItemView, QFrame, QVBoxLayout, QScrollArea

from feeluown.library import SearchType
from feeluown.gui.page_containers.table import TableContainer, Renderer
from feeluown.gui.widgets.img_card_list import ImgCardListDelegate
from feeluown.gui.widgets.songs import SongsTableView, ColumnsMode
from feeluown.gui.base_renderer import TabBarRendererMixin
from feeluown.gui.helpers import BgTransparentMixin, unify_scroll_area_style, \
    set_widget_bg_transparent
from feeluown.gui.widgets.magicbox import KeySourceIn, KeyType
from feeluown.gui.widgets.header import LargeHeader, MidHeader
from feeluown.gui.widgets.accordion import Accordion
from feeluown.gui.widgets.labels import MessageLabel
from feeluown.utils.reader import create_reader


Tabs = [('歌曲', SearchType.so),
        ('专辑', SearchType.al),
        ('歌手', SearchType.ar),
        ('歌单', SearchType.pl),
        ('视频', SearchType.vi)]


def get_tab_idx(search_type):
    for i, tab in enumerate(Tabs):
        if tab[1] == search_type:
            return i
    raise ValueError("unknown search type")


class SearchResultView(QScrollArea):
    """
    Usage:
        view = SearchResultView(app)
        await view.search_and_render(q, search_type, source_in)
    """
    def __init__(self, app, transparent_bg=True, parent=None):
        super().__init__(parent=parent)

        self.setWidgetResizable(True)
        self.setFrameShape(QFrame.NoFrame)
        unify_scroll_area_style(self)
        if transparent_bg:
            set_widget_bg_transparent(self)

        self.body = Body(app)
        self.setWidget(self.body)

    def fillable_bg_height(self):
        """Implement VFillableBg protocol"""
        return self.body.height() - self.body.accordion.height()

    async def search_and_render(self, q, search_type, source_in):
        await self.body.search_and_render(q, search_type, source_in)


class Body(QFrame, BgTransparentMixin):
    def __init__(self, app, **kwargs):
        super().__init__(**kwargs)

        self._app = app

        self.title = LargeHeader()
        self.hint = MessageLabel()
        self.accordion = Accordion()

        self._layout = QVBoxLayout(self)
        self._layout.setContentsMargins(20, 0, 20, 0)
        self._layout.setSpacing(0)
        self._layout.addSpacing(30)
        self._layout.addWidget(self.title)
        self._layout.addSpacing(10)
        self._layout.addWidget(self.hint)
        self._layout.addSpacing(10)
        self._layout.addWidget(self.accordion)
        self._layout.addStretch(0)

    async def search_and_render(self, q, search_type, source_in):
        # pylint: disable=too-many-locals,too-many-statements
        view = self
        app = self._app

        self.title.setText(f'搜索“{q}”')

        tab_index = get_tab_idx(search_type)
        succeed = 0
        start = datetime.now()
        is_first = True  # Is first search result.
        if source_in is not None:
            source_count = len(source_in)
        else:
            source_count = len(app.library.list())
        hint_msgs = [f'正在搜索 {source_count} 个资源提供方...']
        view.hint.show_msg('\n'.join(hint_msgs))
        async for result in app.library.a_search(
                q, type_in=search_type, source_in=source_in, return_err=True):
            if result.err_msg:
                hint_msgs.append(f'搜索 {result.source} 的资源出错：{result.err_msg}')
                view.hint.show_msg('\n'.join(hint_msgs))
                continue

            table_container = TableContainer(app, view.accordion)
            table_container.layout().setContentsMargins(0, 0, 0, 0)

            # HACK: set fixed row for tables.
            # pylint: disable=protected-access
            for table in table_container._tables:
                assert isinstance(table, QAbstractItemView)
                delegate = table.itemDelegate()
                if isinstance(delegate, ImgCardListDelegate):
                    # FIXME: set fixed_row_count in better way.
                    table._fixed_row_count = 2  # type: ignore[attr-defined]
                    delegate.update_settings("card_min_width", 140)
                elif isinstance(table, SongsTableView):
                    table._fixed_row_count = 8
                    table._row_height = table.verticalHeader().defaultSectionSize()

            renderer = SearchResultRenderer(q, tab_index, source_in=source_in)
            await table_container.set_renderer(renderer)
            _, search_type, attrname, show_handler = renderer.tabs[tab_index]
            objects = getattr(result, attrname) or []
            if not objects:  # Result is empty.
                hint_msgs.append(f'搜索 {result.source} 资源，提供方返回空')
                view.hint.show_msg('\n'.join(hint_msgs))
                continue

            succeed += 1
            if search_type is SearchType.so:
                show_handler(  # type: ignore[operator]
                    create_reader(objects), columns_mode=ColumnsMode.playlist)
            else:
                show_handler(create_reader(objects))  # type: ignore[operator]
            source = objects[0].source
            provider = app.library.get(source)
            provider_name = provider.name
            if is_first is False:
                table_container.hide()
            view.accordion.add_section(MidHeader(provider_name), table_container, 6, 12)
            renderer.meta_widget.hide()
            renderer.toolbar.hide()
            is_first = False
        time_cost = (datetime.now() - start).total_seconds()
        hint_msgs.pop(0)
        hint_msgs.insert(0, f'搜索完成，共有 {succeed} 个有效的结果，花费 {time_cost:.2f}s')
        view.hint.show_msg('\n'.join(hint_msgs))


class SearchResultRenderer(Renderer, TabBarRendererMixin):
    def __init__(self, q, tab_index, source_in=None):
        self.q = q
        self.tab_index = tab_index
        self.source_in = source_in

        self.tabs = [
            (*Tabs[0], 'songs', self.show_songs),
            (*Tabs[1], 'albums', self.show_albums),
            (*Tabs[2], 'artists', self.show_artists),
            (*Tabs[3], 'playlists', self.show_playlists),
            (*Tabs[4], 'videos', self.show_videos),
        ]

    async def render(self):
        self.render_tab_bar()

    def render_by_tab_index(self, tab_index):
        search_type = self.tabs[tab_index][1]
        self._app.browser.local_storage[KeyType] = search_type.value
        query = {'q': self.q, 'type': search_type.value}
        source_in = self._app.browser.local_storage.get(KeySourceIn, None)
        if source_in is not None:
            query['source_in'] = source_in
        self._app.browser.goto(page='/search', query=query)
