"""
Main window for the microscopy object detection application.
"""

from PySide6.QtWidgets import (
    QMainWindow,
    QTabWidget,
    QMenuBar,
    QMenu,
    QStatusBar,
    QMessageBox,
    QWidget,
    QVBoxLayout,
    QLabel,
)
from PySide6.QtCore import Qt, QTimer, QSettings
from PySide6.QtGui import QAction, QKeySequence

from src.database.db_manager import DatabaseManager
from src.utils.config_manager import ConfigManager
from src.utils.logger import get_logger
from src.gui.dialogs.config_dialog import ConfigDialog
from src.gui.tabs.detection_tab import DetectionTab
from src.gui.tabs.training_tab import TrainingTab
from src.gui.tabs.validation_tab import ValidationTab
from src.gui.tabs.results_tab import ResultsTab
from src.gui.tabs.annotation_tab import AnnotationTab


logger = get_logger(__name__)


class MainWindow(QMainWindow):
    """Main application window."""

    def __init__(self):
        super().__init__()

        # Initialize managers
        self.config_manager = ConfigManager()

        db_path = self.config_manager.get_database_path()
        self.db_manager = DatabaseManager(db_path)

        logger.info("Main window initializing")

        # Setup UI
        self.setWindowTitle("Microscopy Object Detection")
        self.setMinimumSize(1200, 800)

        self._create_menu_bar()
        self._create_tab_widget()
        self._create_status_bar()

        # Restore window geometry or center window on screen
        self._restore_window_state()

        logger.info("Main window initialized")

    def _create_menu_bar(self):
        """Create application menu bar."""
        menubar = self.menuBar()

        # File menu
        file_menu = menubar.addMenu("&File")

        settings_action = QAction("&Settings", self)
        settings_action.setShortcut(QKeySequence("Ctrl+,"))
        settings_action.triggered.connect(self._show_settings)
        file_menu.addAction(settings_action)

        file_menu.addSeparator()

        exit_action = QAction("E&xit", self)
        exit_action.setShortcut(QKeySequence("Ctrl+Q"))
        exit_action.triggered.connect(self.close)
        file_menu.addAction(exit_action)

        # View menu
        view_menu = menubar.addMenu("&View")

        refresh_action = QAction("&Refresh", self)
        refresh_action.setShortcut(QKeySequence("F5"))
        refresh_action.triggered.connect(self._refresh_current_tab)
        view_menu.addAction(refresh_action)

        # Tools menu
        tools_menu = menubar.addMenu("&Tools")

        db_stats_action = QAction("Database &Statistics", self)
        db_stats_action.triggered.connect(self._show_database_stats)
        tools_menu.addAction(db_stats_action)

        # Help menu
        help_menu = menubar.addMenu("&Help")

        about_action = QAction("&About", self)
        about_action.triggered.connect(self._show_about)
        help_menu.addAction(about_action)

        docs_action = QAction("&Documentation", self)
        docs_action.triggered.connect(self._show_documentation)
        help_menu.addAction(docs_action)

    def _create_tab_widget(self):
        """Create main tab widget with all tabs."""
        self.tab_widget = QTabWidget()
        self.tab_widget.setTabPosition(QTabWidget.North)

        # Create tabs
        try:
            self.detection_tab = DetectionTab(self.db_manager, self.config_manager)
            self.training_tab = TrainingTab(self.db_manager, self.config_manager)
            self.validation_tab = ValidationTab(self.db_manager, self.config_manager)
            self.results_tab = ResultsTab(self.db_manager, self.config_manager)
            self.annotation_tab = AnnotationTab(self.db_manager, self.config_manager)

            # Add tabs to widget
            self.tab_widget.addTab(self.detection_tab, "Detection")
            self.tab_widget.addTab(self.training_tab, "Training")
            self.tab_widget.addTab(self.validation_tab, "Validation")
            self.tab_widget.addTab(self.results_tab, "Results")
            self.tab_widget.addTab(self.annotation_tab, "Annotation (Future)")

            # Connect tab change signal
            self.tab_widget.currentChanged.connect(self._on_tab_changed)

        except Exception as e:
            logger.error(f"Error creating tabs: {e}")
            # Create placeholder
            placeholder = QWidget()
            layout = QVBoxLayout()
            layout.addWidget(QLabel(f"Error creating tabs: {e}"))
            placeholder.setLayout(layout)
            self.tab_widget.addTab(placeholder, "Error")

        self.setCentralWidget(self.tab_widget)

    def _create_status_bar(self):
        """Create status bar."""
        self.status_bar = QStatusBar()
        self.setStatusBar(self.status_bar)

        # Add permanent widgets to status bar
        self.status_label = QLabel("Ready")
        self.status_bar.addWidget(self.status_label)

        # Initial status message
        self._update_status("Ready")

    def _center_window(self):
        """Center window on screen."""
        screen = self.screen().geometry()
        size = self.geometry()
        self.move(
            (screen.width() - size.width()) // 2, (screen.height() - size.height()) // 2
        )

    def _restore_window_state(self):
        """Restore window geometry from settings or center window."""
        settings = QSettings("microscopy_app", "object_detection")
        geometry = settings.value("main_window/geometry")

        if geometry:
            self.restoreGeometry(geometry)
            logger.debug("Restored window geometry from settings")
        else:
            self._center_window()
            logger.debug("Centered window on screen")

    def _save_window_state(self):
        """Save window geometry to settings."""
        settings = QSettings("microscopy_app", "object_detection")
        settings.setValue("main_window/geometry", self.saveGeometry())
        logger.debug("Saved window geometry to settings")

    def _show_settings(self):
        """Show settings dialog."""
        logger.info("Opening settings dialog")
        dialog = ConfigDialog(self.config_manager, self)
        if dialog.exec():
            self._apply_settings()
            self._update_status("Settings saved")

    def _apply_settings(self):
        """Apply changed settings."""
        logger.info("Applying settings changes")
        # Reload configuration in all tabs if needed
        try:
            if hasattr(self, "detection_tab"):
                self.detection_tab.refresh()
            if hasattr(self, "training_tab"):
                self.training_tab.refresh()
            if hasattr(self, "results_tab"):
                self.results_tab.refresh()
        except Exception as e:
            logger.error(f"Error applying settings: {e}")

    def _refresh_current_tab(self):
        """Refresh the current tab."""
        current_widget = self.tab_widget.currentWidget()
        if hasattr(current_widget, "refresh"):
            current_widget.refresh()
            self._update_status("Tab refreshed")

    def _on_tab_changed(self, index: int):
        """Handle tab change event."""
        tab_name = self.tab_widget.tabText(index)
        logger.debug(f"Switched to tab: {tab_name}")
        self._update_status(f"Viewing: {tab_name}")

    def _show_database_stats(self):
        """Show database statistics dialog."""
        try:
            stats = self.db_manager.get_detection_statistics()

            message = f"""
            <h3>Database Statistics</h3>
            <p><b>Total Detections:</b> {stats.get('total_detections', 0)}</p>
            <p><b>Average Confidence:</b> {stats.get('average_confidence', 0):.2%}</p>
            <p><b>Classes:</b></p>
            <ul>
            """

            for class_name, count in stats.get("class_counts", {}).items():
                message += f"<li>{class_name}: {count}</li>"

            message += "</ul>"

            QMessageBox.information(self, "Database Statistics", message)

        except Exception as e:
            logger.error(f"Error getting database stats: {e}")
            QMessageBox.warning(
                self, "Error", f"Failed to get database statistics:\n{str(e)}"
            )

    def _show_about(self):
        """Show about dialog."""
        about_text = """
        <h2>Microscopy Object Detection Application</h2>
        <p><b>Version:</b> 1.0.0</p>
        <p>A desktop application for detecting organelles and membrane branching 
        structures in microscopy images using YOLOv8.</p>
        
        <p><b>Features:</b></p>
        <ul>
            <li>Object detection with YOLOv8</li>
            <li>Model training and validation</li>
            <li>Detection results storage</li>
            <li>Interactive visualization</li>
            <li>Export capabilities</li>
        </ul>
        
        <p><b>Technologies:</b></p>
        <ul>
            <li>Ultralytics YOLOv8</li>
            <li>PySide6</li>
            <li>pyqtgraph</li>
            <li>SQLite</li>
        </ul>
        """

        QMessageBox.about(self, "About", about_text)

    def _show_documentation(self):
        """Show documentation."""
        QMessageBox.information(
            self,
            "Documentation",
            "Please refer to README.md and ARCHITECTURE.md files in the project directory.",
        )

    def _update_status(self, message: str, timeout: int = 5000):
        """
        Update status bar message.

        Args:
            message: Status message to display
            timeout: Time in milliseconds to show message (0 for permanent)
        """
        self.status_label.setText(message)
        if timeout > 0:
            QTimer.singleShot(timeout, lambda: self.status_label.setText("Ready"))

    def closeEvent(self, event):
        """Handle window close event."""
        reply = QMessageBox.question(
            self,
            "Confirm Exit",
            "Are you sure you want to exit?",
            QMessageBox.Yes | QMessageBox.No,
            QMessageBox.No,
        )

        if reply == QMessageBox.Yes:
            # Save window state before closing
            self._save_window_state()

            # Persist tab state and stop background work before exit
            if hasattr(self, "training_tab"):
                self.training_tab.shutdown()
            if hasattr(self, "annotation_tab"):
                self.annotation_tab.save_state()

            logger.info("Application closing")
            event.accept()
        else:
            event.ignore()