# Standard library imports
from typing import cast, Optional, TYPE_CHECKING

# PyQt imports
from PyQt6.QtCore import (
    QTimer,
)
from PyQt6.QtWidgets import (
    QAbstractItemView,
    QTableView,
)

# Third party imports
# import line_profiler

# App imports
from audacity_controller import AudacityController
from classes import ApplicationError, MusicMusterSignals, PlaylistStyle
from config import Config
from helpers import (
    show_warning,
)
from log import log
from models import db, Settings
from querylistmodel import QuerylistModel

if TYPE_CHECKING:
    from musicmuster import Window


class QuerylistTab(QTableView):
    """
    The querylist view
    """

    def __init__(self, musicmuster: "Window", model: QuerylistModel) -> None:
        super().__init__()

        # Save passed settings
        self.musicmuster = musicmuster

        self.playlist_id = model.playlist_id

        # Set up widget
        self.setAlternatingRowColors(True)
        self.setVerticalScrollMode(QAbstractItemView.ScrollMode.ScrollPerPixel)

        # Set our custom style - this draws the drop indicator across the whole row
        self.setStyle(PlaylistStyle())

        # We will enable dragging when rows are selected. Disabling it
        # here means we can click and drag to select rows.
        self.setDragEnabled(False)

        # Connect signals
        self.signals = MusicMusterSignals()
        self.signals.resize_rows_signal.connect(self.resize_rows)

        # Selection model
        self.setSelectionMode(QAbstractItemView.SelectionMode.ExtendedSelection)
        self.setSelectionBehavior(QAbstractItemView.SelectionBehavior.SelectRows)

        # Enable item editing for checkboxes
        self.clicked.connect(self.handle_row_click)

        # Set up for Audacity
        try:
            self.ac: Optional[AudacityController] = AudacityController()
        except ApplicationError as e:
            self.ac = None
            show_warning(self.musicmuster, "Audacity error", str(e))

        # Load model, set column widths
        self.setModel(model)
        self._set_column_widths()

        # Stretch last column *after* setting column widths which is
        # *much* faster
        h_header = self.horizontalHeader()
        if h_header:
            h_header.sectionResized.connect(self._column_resize)
            h_header.setStretchLastSection(True)
        # Resize on vertical header click
        v_header = self.verticalHeader()
        if v_header:
            v_header.setMinimumSectionSize(5)
            v_header.sectionHandleDoubleClicked.disconnect()
            v_header.sectionHandleDoubleClicked.connect(self.resizeRowToContents)

        # Setting ResizeToContents causes screen flash on load
        self.resize_rows()

    # ########## Overridden class functions ##########

    def resizeRowToContents(self, row):
        super().resizeRowToContents(row)
        self.verticalHeader().resizeSection(row, self.sizeHintForRow(row))

    def resizeRowsToContents(self):
        header = self.verticalHeader()
        for row in range(self.model().rowCount()):
            hint = self.sizeHintForRow(row)
            header.resizeSection(row, hint)

    # ########## Custom functions ##########
    def clear_selection(self) -> None:
        """Unselect all tracks and reset drag mode"""

        self.clearSelection()
        # We want to remove the focus from any widget otherwise keyboard
        # activity may edit a cell.
        fw = self.musicmuster.focusWidget()
        if fw:
            fw.clearFocus()
        self.setDragEnabled(False)

    def _column_resize(self, column_number: int, _old: int, _new: int) -> None:
        """
        Called when column width changes. Save new width to database.
        """

        log.debug(f"_column_resize({column_number=}, {_old=}, {_new=}")

        header = self.horizontalHeader()
        if not header:
            return

        # Resize rows if necessary
        self.resizeRowsToContents()

        with db.Session() as session:
            attr_name = f"querylist_col_{column_number}_width"
            record = Settings.get_setting(session, attr_name)
            record.f_int = self.columnWidth(column_number)
            session.commit()

    def handle_row_click(self, index):
        self.model().toggle_row_selection(index.row())
        self.clearSelection()

    def model(self) -> QuerylistModel:
        """
        Override return type to keep mypy happy in this module
        """

        return cast(QuerylistModel, super().model())

    def resize_rows(self, playlist_id: Optional[int] = None) -> None:
        """
        If playlist_id is us, resize rows
        """

        log.debug(f"resize_rows({playlist_id=}) {self.playlist_id=}")

        if playlist_id and playlist_id != self.playlist_id:
            return

        # Suggestion from phind.com
        def resize_row(row, count=1):
            row_count = self.model().rowCount()
            for todo in range(count):
                if row < row_count:
                    self.resizeRowToContents(row)
                    row += 1
            if row < row_count:
                QTimer.singleShot(0, lambda: resize_row(row, count))

        # Start resizing from row 0, 10 rows at a time
        QTimer.singleShot(0, lambda: resize_row(0, Config.RESIZE_ROW_CHUNK_SIZE))

    def _set_column_widths(self) -> None:
        """Column widths from settings"""

        log.debug("_set_column_widths()")

        header = self.horizontalHeader()
        if not header:
            return

        # Last column is set to stretch so ignore it here
        with db.Session() as session:
            for column_number in range(header.count() - 1):
                attr_name = f"querylist_col_{column_number}_width"
                record = Settings.get_setting(session, attr_name)
                if record.f_int is not None:
                    self.setColumnWidth(column_number, record.f_int)
                else:
                    self.setColumnWidth(column_number, Config.DEFAULT_COLUMN_WIDTH)

    def tab_live(self) -> None:
        """Noop for query tabs"""

        return