from PySide6.QtWidgets import (
    QApplication,
    QMainWindow,
    QWidget,
    QVBoxLayout,
    QHBoxLayout,
    QStackedWidget,
    QToolButton,
    QMenu,
    QPushButton,
    QLabel,
)
from PySide6.QtCore import QSize, Qt, QTimer
from PySide6.QtGui import QFont
from themes import THEME_DAY, THEME_NIGHT
from screens.media import MediaScreen
from screens.stub import StubScreen
from screens.settings import SettingsScreen


class MainWindowNew(QMainWindow):
    def __init__(self, app: QApplication):
        super().__init__()
        self.app = app
        self.is_night = True

        self.setWindowTitle("Car UI (New)")
        self.setMinimumSize(QSize(1024, 600))
        self.showFullScreen()

        central = QWidget()
        outer = QVBoxLayout(central)
        outer.setContentsMargins(0, 0, 0, 0)
        outer.setSpacing(0)

        self.topbar = QWidget()
        self.topbar.setObjectName("TopBar")
        self.topbar.setMinimumHeight(86)
        top = QHBoxLayout(self.topbar)
        top.setContentsMargins(18, 14, 18, 14)
        top.setSpacing(14)

        self.menu_button = QToolButton()
        self.menu_button.setObjectName("MenuButton")
        self.menu_button.setText("▼")
        self.menu_button.setPopupMode(QToolButton.InstantPopup)
        self.menu_button.setCursor(Qt.PointingHandCursor)
        self.menu_button.setMinimumSize(64, 48)

        menu = QMenu(self.menu_button)
        menu.setMinimumWidth(340)
        self.menu_button.setMenu(menu)
        self.act_media = menu.addAction("Media")
        self.act_car = menu.addAction("Car")
        self.act_maps = menu.addAction("Maps")

        self.btn_back = QPushButton("Назад")
        self.btn_back.setObjectName("TopBackBtn")
        self.btn_back.setMinimumSize(120, 48)
        self.btn_back.setVisible(False)

        self.lbl_source = QLabel("Media")
        self.lbl_source.setFont(QFont("", 20, 600))

        self.lbl_bt = QLabel("Источник")
        self.lbl_bt.setObjectName("BluetoothStatus")
        self.lbl_bt.setFont(QFont("", 18, 600))

        self.lbl_time = QLabel("--:--")
        self.lbl_time.setFont(QFont("", 20, 600))

        self.btn_settings = QPushButton("⚙")
        self.btn_settings.setObjectName("SettingsButton")
        self.btn_settings.setMinimumSize(56, 48)
        self.btn_settings.clicked.connect(self.toggle_settings)

        top.addWidget(self.menu_button)
        top.addWidget(self.btn_back)
        top.addWidget(self.lbl_source)
        top.addStretch(1)
        top.addWidget(self.lbl_bt)
        top.addWidget(self.lbl_time)
        top.addWidget(self.btn_settings)

        self.stack = QStackedWidget()
        self.media_screen = MediaScreen()
        self.stack.addWidget(self.media_screen)  # 0
        self.stack.addWidget(StubScreen("Car"))  # 1
        self.stack.addWidget(StubScreen("Maps")) # 2
        self.settings_screen = SettingsScreen()
        self.stack.addWidget(self.settings_screen)   # 3

        self.settings_idx = 3
        self.last_non_settings_idx = 0
        self.settings_title = "Настройки"
        self.settings_show_back = False

        self.act_media.triggered.connect(lambda: self.go(0))
        self.act_car.triggered.connect(lambda: self.go(1))
        self.act_maps.triggered.connect(lambda: self.go(2))
        self.media_screen.source_changed.connect(self.lbl_bt.setText)
        self.settings_screen.view_changed.connect(self._on_settings_view_changed)
        self.btn_back.clicked.connect(self._settings_back)

        outer.addWidget(self.topbar)
        outer.addWidget(self.stack, 1)

        self.setCentralWidget(central)

        self._clock_timer = QTimer(self)
        self._clock_timer.timeout.connect(self.update_time)
        self._clock_timer.start(500)

        self.apply_theme()
        self.go(0)
        self.lbl_bt.setText(self.media_screen.source.text())

    def apply_theme(self):
        self.app.setStyleSheet(THEME_NIGHT if self.is_night else THEME_DAY)

    def _sync_topbar(self, idx: int):
        is_settings = idx == self.settings_idx
        self.menu_button.setVisible(not is_settings)
        self.btn_back.setVisible(is_settings and self.settings_show_back)
        self.lbl_bt.setVisible(not is_settings)
        self.lbl_time.setVisible(not is_settings)
        self.btn_settings.setText("✕" if is_settings else "⚙")
        if is_settings:
            self.lbl_source.setText(self.settings_title)

    def toggle_settings(self):
        if self.stack.currentIndex() == self.settings_idx:
            self.go(self.last_non_settings_idx)
        else:
            self.settings_screen.show_list()
            self.go(self.settings_idx)

    def update_time(self):
        from datetime import datetime
        self.lbl_time.setText(datetime.now().strftime("%H:%M"))

    def go(self, idx: int):
        if idx != self.settings_idx:
            self.last_non_settings_idx = idx
        self.stack.setCurrentIndex(idx)
        if idx == 0:
            self.lbl_source.setText("Media")
        elif idx == 1:
            self.lbl_source.setText("Car")
        elif idx == 2:
            self.lbl_source.setText("Maps")
        self._sync_topbar(idx)

    def _on_settings_view_changed(self, title: str, show_back: bool):
        self.settings_title = title
        self.settings_show_back = show_back
        if self.stack.currentIndex() == self.settings_idx:
            self._sync_topbar(self.settings_idx)

    def _settings_back(self):
        self.settings_screen.show_list()