"""
ui/profile_manager_ui.py

Profile menu button (📁) in the top-right toolbar.
Handles New / Load / Save / Save As via file dialogs.
Thin UI layer — all serialisation is in core/profile.py.
"""

import os
from PyQt6.QtWidgets import (
    QMenu, QPushButton, QFileDialog, QInputDialog,
    QMessageBox, QApplication,
)
from PyQt6.QtCore import QPoint
from PyQt6.QtGui  import QAction

from core.profile import Profile, ProfileManager


PROFILE_EXT    = ".labdaq"
PROFILE_FILTER = f"LabDAQ Profile (*{PROFILE_EXT});;All files (*)"


class ProfileButton(QPushButton):
    """
    A '📁  File' button that shows New / Load / Save / Save As.
    Placed in the toolbar top-right.

    Caller provides callbacks:
        on_new()           — reset to blank state
        get_profile()      — return a Profile representing current state
        apply_profile(p)   — restore state from a Profile
    """

    def __init__(self, on_new, get_profile, apply_profile, parent=None):
        super().__init__("📁  File", parent)
        self.setObjectName("toolbarSectionBtn")
        self._on_new       = on_new
        self._get_profile  = get_profile
        self._apply_profile = apply_profile
        self._current_path: str = ""
        self.clicked.connect(self._show_menu)

    # ── Menu ──────────────────────────────────────────────────────────────────

    def _show_menu(self):
        menu = QMenu(self)
        menu.setObjectName("profileMenu")

        a_new     = menu.addAction("📄  New Profile")
        menu.addSeparator()
        a_open    = menu.addAction("📂  Load Profile…")
        menu.addSeparator()
        a_save    = menu.addAction("💾  Save")
        a_save_as = menu.addAction("💾  Save As…")

        a_save.setEnabled(bool(self._current_path))

        a_new.triggered.connect(self._do_new)
        a_open.triggered.connect(self._do_load)
        a_save.triggered.connect(self._do_save)
        a_save_as.triggered.connect(self._do_save_as)

        # Show below the button
        pos = self.mapToGlobal(QPoint(0, self.height()))
        menu.exec(pos)

    # ── Actions ───────────────────────────────────────────────────────────────

    def _do_new(self):
        reply = QMessageBox.question(
            self, "New Profile",
            "Discard current configuration and start a blank profile?",
            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
        )
        if reply == QMessageBox.StandardButton.Yes:
            self._current_path = ""
            self._on_new()
            self._update_title()

    def _do_load(self):
        path, _ = QFileDialog.getOpenFileName(
            self, "Load Profile", self._default_dir(),
            PROFILE_FILTER,
        )
        if not path:
            return
        try:
            profile = Profile.load(path)
            self._apply_profile(profile)
            self._current_path = path
            self._update_title(profile.name)
        except Exception as e:
            QMessageBox.critical(self, "Load Failed", str(e))

    def _do_save(self):
        if not self._current_path:
            self._do_save_as()
            return
        self._save_to(self._current_path)

    def _do_save_as(self):
        # Ask for profile name
        name, ok = QInputDialog.getText(
            self, "Profile Name", "Profile name:",
            text=os.path.splitext(os.path.basename(self._current_path))[0]
                if self._current_path else "My Profile",
        )
        if not ok or not name.strip():
            return
        name = name.strip()

        path, _ = QFileDialog.getSaveFileName(
            self, "Save Profile As",
            os.path.join(self._default_dir(), name + PROFILE_EXT),
            PROFILE_FILTER,
        )
        if not path:
            return
        if not path.endswith(PROFILE_EXT):
            path += PROFILE_EXT
        self._save_to(path, name)

    def _save_to(self, path: str, name: str = ""):
        try:
            profile = self._get_profile(name or os.path.splitext(
                os.path.basename(path))[0])
            profile.save(path)
            self._current_path = path
            self._update_title(profile.name)
        except Exception as e:
            QMessageBox.critical(self, "Save Failed", str(e))

    # ── Helpers ───────────────────────────────────────────────────────────────

    def _default_dir(self) -> str:
        d = os.path.join(os.path.expanduser("~"), "labdaq_profiles")
        os.makedirs(d, exist_ok=True)
        return d

    def _update_title(self, name: str = ""):
        app = QApplication.instance()
        if app and hasattr(app, "topLevelWidgets"):
            for w in app.topLevelWidgets():
                if hasattr(w, "setWindowTitle") and "LabDAQ" in (w.windowTitle() or ""):
                    title = "LabDAQ"
                    if name:
                        title += f"  —  {name}"
                    if self._current_path:
                        title += f"  [{os.path.basename(self._current_path)}]"
                    w.setWindowTitle(title)
                    break