# target_simulator/gui/logger_panel.py
"""
A small Toplevel UI to inspect and change logger levels at runtime.
"""
import tkinter as tk
from tkinter import ttk, messagebox
import logging
from typing import List
from target_simulator.utils.config_manager import ConfigManager
import os
import json

LEVELS = [
    ("NOTSET", logging.NOTSET),
    ("DEBUG", logging.DEBUG),
    ("INFO", logging.INFO),
    ("WARNING", logging.WARNING),
    ("ERROR", logging.ERROR),
    ("CRITICAL", logging.CRITICAL),
]


class LoggerPanel(tk.Toplevel):
    """Toplevel window that allows setting logger levels at runtime."""

    def __init__(self, master=None):
        super().__init__(master)
        self.title("Logger Levels")
        self.geometry("520x420")
        self.transient(master)
        self.grab_set()

        self.logger_names = []  # type: List[str]

        # Config manager for persistence
        try:
            self._cfg = ConfigManager()
        except Exception:
            self._cfg = None

        self._create_widgets()
        self._populate_logger_list()

        # Load persisted selections and levels
        try:
            self._load_persisted()
        except Exception:
            pass

    def _create_widgets(self):
        top = ttk.Frame(self)
        top.pack(fill=tk.BOTH, expand=True, padx=8, pady=8)

        # Left: filter + list of logger names
        left = ttk.Frame(top)
        left.pack(side=tk.LEFT, fill=tk.BOTH, expand=True)

        ttk.Label(left, text="Filter:").pack(anchor=tk.W)
        self.filter_var = tk.StringVar(value="")
        self.filter_entry = ttk.Entry(left, textvariable=self.filter_var)
        self.filter_entry.pack(fill=tk.X, padx=(0, 6), pady=(2, 4))
        # Call _on_filter_change on text changes
        try:
            # Python 3.6+ trace_add preferred
            self.filter_var.trace_add("write", lambda *args: self._on_filter_change())
        except Exception:
            # Fallback for older trace
            try:
                self.filter_var.trace("w", lambda *args: self._on_filter_change())
            except Exception:
                pass

        ttk.Label(left, text="Available loggers:").pack(anchor=tk.W)
        self.logger_listbox = tk.Listbox(left, exportselection=False)
        self.logger_listbox.pack(fill=tk.BOTH, expand=True, padx=(0, 6), pady=(4, 0))
        self.logger_listbox.bind("<<ListboxSelect>>", self._on_select_logger)

        # Right: controls
        right = ttk.Frame(top)
        right.pack(side=tk.RIGHT, fill=tk.Y)

        ttk.Label(right, text="Selected logger:").pack(anchor=tk.W)
        self.selected_name_var = tk.StringVar(value="")
        ttk.Label(right, textvariable=self.selected_name_var, foreground="blue").pack(anchor=tk.W, pady=(0, 6))

        ttk.Label(right, text="Level:").pack(anchor=tk.W)
        self.level_var = tk.StringVar(value="INFO")
        level_names = [n for n, v in LEVELS]
        self.level_combo = ttk.Combobox(right, values=level_names, textvariable=self.level_var, state="readonly", width=12)
        self.level_combo.pack(anchor=tk.W, pady=(0, 6))

        ttk.Button(right, text="Apply", command=self._apply_level).pack(fill=tk.X, pady=(6, 4))
        ttk.Button(right, text="Reset to NOTSET", command=self._reset_level).pack(fill=tk.X)
        ttk.Button(right, text="Restore defaults", command=self._restore_defaults).pack(fill=tk.X, pady=(6, 0))

        ttk.Separator(self).pack(fill=tk.X, pady=6)

        bottom = ttk.Frame(self)
        bottom.pack(fill=tk.X, padx=8, pady=6)

        ttk.Label(bottom, text="Add / open logger by name:").pack(anchor=tk.W)
        self.new_logger_var = tk.StringVar()
        entry = ttk.Entry(bottom, textvariable=self.new_logger_var)
        entry.pack(side=tk.LEFT, fill=tk.X, expand=True, padx=(0, 6))
        ttk.Button(bottom, text="Open", command=self._open_named_logger).pack(side=tk.LEFT)

        ttk.Button(self, text="Refresh", command=self._populate_logger_list).pack(side=tk.RIGHT, padx=8, pady=(0, 8))
        ttk.Button(self, text="Export", command=self._export_prefs).pack(side=tk.RIGHT, padx=(0,8), pady=(0,8))
        ttk.Button(self, text="Close", command=self._on_close).pack(side=tk.RIGHT, pady=(0, 8))

    def _gather_logger_names(self) -> List[str]:
        # Gather logger names from the logging manager plus some defaults
        manager = logging.root.manager
        names = list(getattr(manager, 'loggerDict', {}).keys())
        # Add a few commonly useful module names if missing
        defaults = [
            'target_simulator',
            'target_simulator.analysis.simulation_state_hub',
            'target_simulator.gui.sfp_debug_window',
            'target_simulator.gui.ppi_display',
            'target_simulator.gui.payload_router',
            'target_simulator.core.sfp_transport',
        ]
        for d in defaults:
            if d not in names:
                names.append(d)
        names = sorted(set(names))
        return names

    def _refresh_list(self):
        """Refresh listbox contents applying current filter against _all_logger_names."""
        try:
            filt = (self.filter_var.get() or "").strip().lower()
        except Exception:
            filt = ""

        # Build filtered list
        if hasattr(self, "_all_logger_names") and self._all_logger_names:
            source = self._all_logger_names
        else:
            source = self.logger_names

        if filt:
            filtered = [n for n in source if filt in n.lower()]
        else:
            filtered = list(source)

        # Remember current selection name to try to preserve it
        try:
            sel_idx = self.logger_listbox.curselection()
            sel_name = self.logger_names[sel_idx[0]] if sel_idx else None
        except Exception:
            sel_name = None

        # Update listbox
        self.logger_listbox.delete(0, tk.END)
        self.logger_names = sorted(filtered)
        for n in self.logger_names:
            self.logger_listbox.insert(tk.END, n)

        # Restore selection if still present
        if sel_name and sel_name in self.logger_names:
            idx = self.logger_names.index(sel_name)
            self.logger_listbox.select_set(idx)
            self.logger_listbox.see(idx)
            self._on_select_logger()

    def _on_filter_change(self, *args):
        """Callback for filter text changes; refresh the list."""
        try:
            self._refresh_list()
        except Exception:
            pass

    def _populate_logger_list(self):
        self.logger_listbox.delete(0, tk.END)
        # Gather and cache the full set of logger names, then refresh list
        self._all_logger_names = self._gather_logger_names()
        # Apply filter and populate listbox
        self._refresh_list()
        # If user previously selected a logger, select it
        try:
            if self._cfg:
                gen = self._cfg.get_general_settings()
                lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
                last = lp.get("last_selected")
                if last and last in self.logger_names:
                    idx = self.logger_names.index(last)
                    self.logger_listbox.select_set(idx)
                    self.logger_listbox.see(idx)
                    self._on_select_logger()
        except Exception:
            pass

    def _on_select_logger(self, event=None):
        sel = self.logger_listbox.curselection()
        if not sel:
            return
        idx = sel[0]
        name = self.logger_names[idx]
        self.selected_name_var.set(name)
        lg = logging.getLogger(name)
        lvl = lg.getEffectiveLevel()
        # Translate to name
        lvl_name = logging.getLevelName(lvl)
        self.level_var.set(lvl_name)

    def _apply_level(self):
        name = self.selected_name_var.get()
        if not name:
            messagebox.showwarning("No logger selected", "Select a logger from the list first.")
            return
        lvl_name = self.level_var.get()
        lvl = next((v for n, v in LEVELS if n == lvl_name), logging.INFO)
        logging.getLogger(name).setLevel(lvl)
        # Persist this selection into dedicated logger_prefs.json (single source of truth)
        try:
            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
            # Read existing prefs
            try:
                with open(prefs_path, 'r', encoding='utf-8') as f:
                    prefs = json.load(f) if f else {}
                    if not isinstance(prefs, dict):
                        prefs = {}
            except Exception:
                prefs = {}

            saved = prefs.get('saved_levels', {}) if isinstance(prefs.get('saved_levels', {}), dict) else {}
            saved[name] = lvl_name
            prefs['saved_levels'] = saved
            prefs['last_selected'] = name
            with open(prefs_path, 'w', encoding='utf-8') as f:
                json.dump(prefs, f, indent=4)
        except Exception:
            pass

        # Post a status message to the application log instead of a modal dialog
        try:
            # Show a transient status in the main UI if available
            parent = getattr(self, 'master', None)
            if parent and hasattr(parent, 'show_status_message'):
                parent.show_status_message(f"Logger '{name}' set to {lvl_name} (saved)")
            else:
                logging.getLogger(__name__).info("Logger '%s' set to %s (persisted)", name, lvl_name)
        except Exception:
            try:
                messagebox.showinfo("Logger level set", f"Logger '{name}' set to {lvl_name}.")
            except Exception:
                pass

    def _reset_level(self):
        name = self.selected_name_var.get()
        if not name:
            messagebox.showwarning("No logger selected", "Select a logger from the list first.")
            return
        logging.getLogger(name).setLevel(logging.NOTSET)
        self.level_var.set('NOTSET')
        # Remove persisted level for this logger from logger_prefs.json
        try:
            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
            try:
                with open(prefs_path, 'r', encoding='utf-8') as f:
                    prefs = json.load(f) if f else {}
                    if not isinstance(prefs, dict):
                        prefs = {}
            except Exception:
                prefs = {}

            saved = prefs.get('saved_levels', {}) if isinstance(prefs.get('saved_levels', {}), dict) else {}
            if name in saved:
                del saved[name]
                prefs['saved_levels'] = saved
                # if last_selected pointed to this logger, remove it
                if prefs.get('last_selected') == name:
                    prefs.pop('last_selected', None)
                with open(prefs_path, 'w', encoding='utf-8') as f:
                    json.dump(prefs, f, indent=4)
        except Exception:
            pass

        try:
            parent = getattr(self, 'master', None)
            if parent and hasattr(parent, 'show_status_message'):
                parent.show_status_message(f"Logger '{name}' reset to NOTSET (saved)")
            else:
                logging.getLogger(__name__).info("Logger '%s' reset to NOTSET (persisted)", name)
        except Exception:
            try:
                messagebox.showinfo("Logger reset", f"Logger '{name}' reset to NOTSET.")
            except Exception:
                pass

    def _open_named_logger(self):
        name = self.new_logger_var.get().strip()
        if not name:
            return
        # If exists in list, select it
        try:
            idx = self._all_logger_names.index(name)
        except ValueError:
            # Add to list
            # Add to cached master list and refresh
            if not hasattr(self, "_all_logger_names"):
                self._all_logger_names = []
            if name not in self._all_logger_names:
                self._all_logger_names.append(name)
                self._all_logger_names.sort()
            self._populate_logger_list()
            idx = self.logger_names.index(name)
        self.logger_listbox.select_clear(0, tk.END)
        self.logger_listbox.select_set(idx)
        self.logger_listbox.see(idx)
        self._on_select_logger()
        # Persist last selected into logger_prefs.json
        try:
            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
            try:
                with open(prefs_path, 'r', encoding='utf-8') as f:
                    prefs = json.load(f) if f else {}
                    if not isinstance(prefs, dict):
                        prefs = {}
            except Exception:
                prefs = {}
            prefs['last_selected'] = name
            with open(prefs_path, 'w', encoding='utf-8') as f:
                json.dump(prefs, f, indent=4)
        except Exception:
            pass
        try:
            parent = getattr(self, 'master', None)
            if parent and hasattr(parent, 'show_status_message'):
                parent.show_status_message(f"Selected logger: {name}")
        except Exception:
            pass

    def _restore_defaults(self):
        """Clear all saved logger preferences and reset those loggers to NOTSET."""
        if not self._cfg:
            try:
                messagebox.showinfo("Restore defaults", "Could not access settings to restore defaults.")
            except Exception:
                pass
            return

        try:
            gen = self._cfg.get_general_settings()
            lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
            saved = lp.get("saved_levels", {}) if isinstance(lp, dict) else {}
            # Reset each saved logger to NOTSET
            for name in list(saved.keys()):
                try:
                    logging.getLogger(name).setLevel(logging.NOTSET)
                except Exception:
                    pass
            # Remove saved_levels
            # Clear dedicated prefs file instead of touching settings.json
            cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
            prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
            try:
                with open(prefs_path, 'w', encoding='utf-8') as f:
                    json.dump({"saved_levels": {}}, f, indent=4)
            except Exception:
                # fallback: attempt to remove the file
                try:
                    if os.path.exists(prefs_path):
                        os.remove(prefs_path)
                except Exception:
                    pass
            logging.getLogger(__name__).info("LoggerPanel: restored defaults and cleared saved preferences")
            # Refresh the list and selection
            self._populate_logger_list()
        except Exception:
            try:
                messagebox.showinfo("Restore defaults", "Failed to restore defaults.")
            except Exception:
                pass

    def _export_prefs(self):
        """Export saved logger preferences to a separate JSON file for inspection."""
        if not self._cfg:
            try:
                messagebox.showinfo("Export prefs", "Settings manager not available; cannot export.")
            except Exception:
                pass
            return

        try:
            gen = self._cfg.get_general_settings()
            lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
            saved = lp.get("saved_levels", {}) if isinstance(lp, dict) else {}
            # Determine export path next to settings.json
            cfg_path = getattr(self._cfg, 'filepath', None)
            export_dir = os.path.dirname(cfg_path) if cfg_path else os.getcwd()
            export_path = os.path.join(export_dir, "logger_prefs.json")
            with open(export_path, 'w', encoding='utf-8') as f:
                json.dump({"saved_levels": saved}, f, indent=4)

            parent = getattr(self, 'master', None)
            if parent and hasattr(parent, 'show_status_message'):
                parent.show_status_message(f"Exported logger prefs to {export_path}")
            else:
                logging.getLogger(__name__).info("Exported logger prefs to %s", export_path)
        except Exception:
            try:
                messagebox.showinfo("Export prefs", "Failed to export logger preferences.")
            except Exception:
                pass

    def _on_close(self):
        try:
            self.grab_release()
        except Exception:
            pass
        self.destroy()

    def _load_persisted(self):
        """Load persisted logger panel settings and apply saved levels."""
        # Prefer reading the dedicated prefs file
        cfg_path = getattr(self._cfg, 'filepath', None) if self._cfg else None
        prefs_path = os.path.join(os.path.dirname(cfg_path), 'logger_prefs.json') if cfg_path else os.path.join(os.getcwd(), 'logger_prefs.json')
        saved = {}
        try:
            if os.path.exists(prefs_path):
                with open(prefs_path, 'r', encoding='utf-8') as f:
                    jp = json.load(f)
                    if isinstance(jp, dict):
                        saved = jp.get('saved_levels', {}) or {}
                        last = jp.get('last_selected')
                        if last:
                            # store last_selected in prefs for later UI use
                            pass
            else:
                # Fallback to settings.json
                if self._cfg:
                    gen = self._cfg.get_general_settings()
                    lp = gen.get("logger_panel", {}) if isinstance(gen, dict) else {}
                    saved = lp.get("saved_levels", {}) if isinstance(lp, dict) else {}
        except Exception:
            saved = {}

        # Apply saved levels to loggers
        for name, lvl_name in (saved or {}).items():
            try:
                lvl = logging.getLevelName(lvl_name)
                if isinstance(lvl, int):
                    logging.getLogger(name).setLevel(lvl)
            except Exception:
                pass