"""Notifications page (M8 config): user-configurable alert settings."""

from __future__ import annotations

from PySide6.QtCore import Qt, Signal
from PySide6.QtWidgets import (
    QCheckBox,
    QDoubleSpinBox,
    QFrame,
    QGridLayout,
    QHBoxLayout,
    QLabel,
    QPushButton,
    QVBoxLayout,
    QWidget,
)

from ..config import load_config, update_config
from ..core import alerts


class NotificationsPage(QWidget):
    changed = Signal()  # settings saved — main window re-applies them live

    def __init__(self) -> None:
        super().__init__()
        self.setObjectName("Page")
        root = QVBoxLayout(self)
        root.setContentsMargins(20, 18, 20, 18)
        root.setSpacing(16)

        title = QLabel("Notifications")
        title.setObjectName("PageTitle")
        root.addWidget(title)

        card = QFrame()
        card.setObjectName("Card")
        v = QVBoxLayout(card)
        v.setContentsMargins(16, 14, 16, 14)
        v.setSpacing(10)
        head = QLabel("Alerts")
        head.setStyleSheet("font-weight: 700; background: transparent;")
        v.addWidget(head)

        self._enabled = QCheckBox("Enable desktop notifications")
        v.addWidget(self._enabled)

        grid = QGridLayout()
        grid.setHorizontalSpacing(12)
        grid.setColumnStretch(2, 1)
        self._gpu = self._spin()
        self._cpu = self._spin()
        grid.addWidget(QLabel("GPU temperature alert"), 0, 0)
        grid.addWidget(self._gpu, 0, 1)
        grid.addWidget(QLabel("CPU temperature alert"), 1, 0)
        grid.addWidget(self._cpu, 1, 1)
        v.addLayout(grid)

        note = QLabel("GPU-lost and new-version alerts are included whenever notifications are enabled.")
        note.setObjectName("Muted")
        note.setWordWrap(True)
        v.addWidget(note)

        buttons = QHBoxLayout()
        save = QPushButton("Save")
        save.setObjectName("PrimaryButton")
        save.clicked.connect(self._save)
        test = QPushButton("Send test")
        test.clicked.connect(self._test)
        buttons.addWidget(save)
        buttons.addWidget(test)
        buttons.addStretch(1)
        v.addLayout(buttons)
        self._status = QLabel("")
        self._status.setObjectName("Muted")
        v.addWidget(self._status)

        root.addWidget(card)
        root.addStretch(1)
        self._load()

    @staticmethod
    def _spin() -> QDoubleSpinBox:
        spin = QDoubleSpinBox()
        spin.setRange(40, 110)
        spin.setDecimals(0)
        spin.setSingleStep(1)
        spin.setSuffix(" °C")
        return spin

    def _load(self) -> None:
        cfg = load_config()
        self._enabled.setChecked(bool(cfg.get("alerts_enabled", True)))
        self._gpu.setValue(float(cfg.get("gpu_temp_alert", 90.0)))
        self._cpu.setValue(float(cfg.get("cpu_temp_alert", 95.0)))

    def _save(self) -> None:
        update_config(
            alerts_enabled=self._enabled.isChecked(),
            gpu_temp_alert=self._gpu.value(),
            cpu_temp_alert=self._cpu.value(),
        )
        self.changed.emit()
        self._status.setText("Saved.")

    def _test(self) -> None:
        ok = alerts.notify("RigDoctor", "Test notification — alerts are working.")
        self._status.setText("Test notification sent." if ok else "notify-send not found — install libnotify-bin (Setup).")