"""Tkinter GUI monitor for PyBusMonitor1553.

Minimal GUI with:
- Treeview showing registered messages (label, CW.raw, size)
- Text log for raw sent/received events
- Buttons: `Initialize`, `Start`, `Stop`, `Refresh`

This scaffold calls `pybusmonitor1553.core.connection_manager` for init/start/stop.
All code, comments and UI text are English.
"""
import tkinter as tk
from tkinter import ttk, scrolledtext, messagebox
# Import connection manager lazily to avoid import-time socket errors
# get_manager will be imported at runtime inside the app instance
MessageDB = None
import threading
import time
import logging
import os
import sys

# Try to import the user's external tkinter logger. If not available, add externals path.
try:
    from tkinter_logger import TkinterLogger, get_logger
except Exception:
    try:
        externals_path = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', '..', 'externals', 'python-tkinter-logger'))
        if externals_path not in sys.path:
            sys.path.insert(0, externals_path)
        from tkinter_logger import TkinterLogger, get_logger
    except Exception:
        TkinterLogger = None
        get_logger = None

# Optional resource monitor (externals/python-resource-monitor)
TkinterResourceMonitor = None
try:
    externals_rm = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', '..', 'externals', 'python-resource-monitor'))
    if externals_rm not in sys.path:
        sys.path.insert(0, externals_rm)
    # Attempt to import the Tkinter integration class
    try:
        from resource_monitor import TkinterResourceMonitor  # module provides class at top-level
    except Exception:
        # fallback to package-like import
        try:
            from target_simulator.utils.resource_monitor import TkinterResourceMonitor
        except Exception:
            TkinterResourceMonitor = None
except Exception:
    TkinterResourceMonitor = None


class MonitorApp(tk.Frame):
    def __init__(self, master=None):
        super().__init__(master)
        self.master = master
        self.pack(fill=tk.BOTH, expand=True)

        # Do not import or create the connection manager at startup.
        # The application will remain idle until the user presses `Initialize`.
        self.manager = None
        self.import_error = None
        self.create_widgets()
        self.update_loop_running = False
        # cache tree item ids by message label for incremental updates
        self._tree_items = {}
        # parents we want to keep always expanded in detail tree
        self._always_open_parents = {}
        # No background bind or retry at startup; user must press Initialize.

    def create_widgets(self):
        # Top Controls Frame
        controls = tk.LabelFrame(self, text="Controls")
        controls.pack(side=tk.TOP, fill=tk.X, padx=6, pady=6)

        btn_fr = tk.Frame(controls)
        btn_fr.pack(side=tk.LEFT, padx=4, pady=4)
        self.init_btn = tk.Button(btn_fr, text="Initialize", command=self.on_init)
        self.init_btn.pack(side=tk.LEFT, padx=4)
        self.start_btn = tk.Button(btn_fr, text="Start", command=self.on_start)
        self.start_btn.pack(side=tk.LEFT, padx=4)
        self.stop_btn = tk.Button(btn_fr, text="Stop", command=self.on_stop)
        self.stop_btn.pack(side=tk.LEFT, padx=4)
        self.refresh_btn = tk.Button(btn_fr, text="Refresh", command=self.refresh_messages)
        self.refresh_btn.pack(side=tk.LEFT, padx=4)
        # Start/Stop are disabled until initialization is completed
        try:
            self.start_btn.config(state=tk.DISABLED)
            self.stop_btn.config(state=tk.DISABLED)
        except Exception:
            pass

        # Filters inside controls
        filter_fr = tk.Frame(controls)
        filter_fr.pack(side=tk.RIGHT, padx=4, pady=4)
        tk.Label(filter_fr, text="Label filter:").pack(side=tk.LEFT)
        self.filter_entry = tk.Entry(filter_fr, width=20)
        self.filter_entry.pack(side=tk.LEFT, padx=4)
        tk.Label(filter_fr, text="Period min (ms):").pack(side=tk.LEFT, padx=(8,0))
        self.period_min = tk.Entry(filter_fr, width=8)
        self.period_min.pack(side=tk.LEFT, padx=4)
        tk.Label(filter_fr, text="max(ms):").pack(side=tk.LEFT)
        self.period_max = tk.Entry(filter_fr, width=8)
        self.period_max.pack(side=tk.LEFT, padx=4)
        tk.Button(filter_fr, text="Apply", command=self.refresh_messages).pack(side=tk.LEFT, padx=6)

        # Middle: Bus Monitor (left) and Details (right)
        middle = tk.Frame(self)
        middle.pack(side=tk.TOP, fill=tk.BOTH, expand=True, padx=6, pady=2)

        bus_frame = tk.LabelFrame(middle, text="Bus Monitor")
        bus_frame.pack(side=tk.LEFT, fill=tk.BOTH, expand=True, padx=(0,6))

        # Message table (columns per screenshot)
        columns = ("label", "cw", "sw", "num", "errs", "period", "wc", "mc")
        self.tree = ttk.Treeview(bus_frame, columns=columns, show="headings", height=14)
        self.tree.heading("label", text="Name")
        self.tree.heading("cw", text="CW")
        self.tree.heading("sw", text="SW")
        self.tree.heading("num", text="Num")
        self.tree.heading("errs", text="Errs")
        self.tree.heading("period", text="period")
        self.tree.heading("wc", text="wc")
        self.tree.heading("mc", text="MC")
        self.tree.column("label", width=100)
        self.tree.column("cw", width=80)
        self.tree.column("sw", width=60)
        self.tree.column("num", width=60)
        self.tree.column("errs", width=60)
        self.tree.column("period", width=80)
        self.tree.column("wc", width=40)
        self.tree.column("mc", width=60)
        self.tree.pack(fill=tk.BOTH, expand=True, padx=6, pady=6)

        # details pane moved to dedicated submodule
        try:
            from .details_pane import DetailsPane
            DETAILS_WIDTH = 520
            DETAILS_HEIGHT = 540
            self._details = DetailsPane(middle, app=self, width=DETAILS_WIDTH, height=DETAILS_HEIGHT)
            # ensure attributes expected by existing methods exist
            self.form_widgets = getattr(self, 'form_widgets', {})
            self.current_form_label = getattr(self, 'current_form_label', None)
            self.current_msg_wrapper = getattr(self, 'current_msg_wrapper', None)
            self.detail_rows = getattr(self, 'detail_rows', {})
            self.detail_selected_label = getattr(self, 'detail_selected_label', None)
            self.detail_accessors = getattr(self, 'detail_accessors', {})
            self._flash_items = getattr(self, '_flash_items', {})
            self._last_detail_update = 0.0
            try:
                self.detail_tree.tag_configure('changed', background='lightyellow')
            except Exception:
                pass
        except Exception:
            # fallback: create minimal placeholder frame if import fails
            details_frame = tk.LabelFrame(middle, text="Details")
            details_frame.pack(side=tk.RIGHT, fill=tk.Y, expand=False, padx=6)
            tk.Label(details_frame, text="Message details:").pack(anchor=tk.W)
            self.detail_tree = ttk.Treeview(details_frame, columns=("param","value"), show="headings")
            self.detail_tree.heading('param', text='Parameter')
            self.detail_tree.heading('value', text='Value')
            self.detail_tree.pack(fill=tk.BOTH, expand=True)

        # Bottom: Log area
        log_frame = tk.LabelFrame(self, text="Log")
        log_frame.pack(side=tk.BOTTOM, fill=tk.BOTH, expand=False, padx=6, pady=6)
        self.log = scrolledtext.ScrolledText(log_frame, height=8)
        self.log.pack(fill=tk.BOTH, expand=True, padx=6, pady=6)

        # Status bar will be added below the whole UI (outside all frames)

        # Initialize external TkinterLogger if available, attach text widget as handler
        self.logger_system = None
        try:
            if TkinterLogger is not None:
                self.logger_system = TkinterLogger(self.master)
                self.logger_system.setup(enable_console=True, enable_tkinter=True)
                self.logger_system.add_tkinter_handler(self.log)
                self.logger = logging.getLogger(__name__)
            else:
                logging.basicConfig(level=logging.INFO)
                self.logger = logging.getLogger(__name__)
                self.logger.info("TkinterLogger not available; using basic logging")
        except Exception as e:
            logging.basicConfig(level=logging.INFO)
            self.logger = logging.getLogger(__name__)
            try:
                self.log.insert(tk.END, f"Logger init error: {e}\n")
            except Exception:
                pass

        # Bind selection
        self.tree.bind('<<TreeviewSelect>>', self.on_tree_select)

        # If import of connection manager failed, disable init/start
        if getattr(self, 'import_error', None):
            try:
                self.init_btn.config(state=tk.DISABLED)
                self.start_btn.config(state=tk.DISABLED)
            except Exception:
                pass

        # Add a global status bar below everything
        self.global_status = tk.Frame(self.master, relief=tk.SUNKEN, bd=1)
        # left / center / right panes
        self.status_left = tk.Label(self.global_status, text="", anchor=tk.W)
        self.status_center = tk.Label(self.global_status, text="", anchor=tk.CENTER)
        # right pane: may use a StringVar updated by external resource monitor
        self.status_resource_var = tk.StringVar()
        self.status_right = tk.Label(self.global_status, textvariable=self.status_resource_var, anchor=tk.E)
        self.status_left.pack(side=tk.LEFT, padx=6)
        self.status_center.pack(side=tk.LEFT, expand=True)
        self.status_right.pack(side=tk.RIGHT, padx=6)
        # pack at the bottom of the main window (below this frame)
        self.global_status.pack(side=tk.BOTTOM, fill=tk.X)

        # If there was an import error, auto-open diagnostics and set status
        if getattr(self, 'import_error', None):
            self.open_diagnostics(auto=True)
            try:
                self.update_status()
            except Exception:
                pass
        else:
            self.update_status()
        # Start resource monitor if available
        self._resource_monitor = None
        try:
            if TkinterResourceMonitor is not None:
                # create and start monitor with a 1s poll interval
                try:
                    self._resource_monitor = TkinterResourceMonitor(self.master, self.status_resource_var, poll_interval=1.0)
                    # start() returns True if psutil available and monitor started
                    try:
                        self._resource_monitor.start()
                    except Exception:
                        pass
                except Exception:
                    self._resource_monitor = None
        except Exception:
            self._resource_monitor = None

    def _get_message_db(self):
        """Lazy import of MessageDB so module import-time socket binds won't crash the GUI."""
        global MessageDB
        if MessageDB is not None:
            return MessageDB
        try:
            import importlib
            try:
                mod = importlib.import_module('Grifo_E_1553lib.messages.messages')
            except Exception:
                mod = importlib.import_module('pybusmonitor1553.Grifo_E_1553lib.messages.messages')
            MessageDB = mod.MessageDB
            return MessageDB
        except Exception as e:
            # record import error so UI can show diagnostics
            self.import_error = str(e)
            return None

    def _fmt_enum(self, val, enum_names):
        """Format a numeric `val` with possible enum name(s).

        `enum_names` is a list of candidate enum class names to try in the
        `Grifo_E_1553lib.data_types.enums` module. Returns a string like
        "3 (RWS)" or the original value if no mapping found.
        """
        # delegate to helper to keep monitor.py small
        try:
            from .monitor_helpers import fmt_enum
            return fmt_enum(val, enum_names)
        except Exception:
            return str(val)

    def _format_ctypes_obj(self, obj, indent=0, max_depth=3):
        """Recursively format ctypes-backed message fields into readable text.

        - Prints simple ctypes numbers as integers
        - For nested objects, recurses up to `max_depth`
        - Uses `_fmt_enum` to annotate enum-like values where possible
        """
        try:
            from .monitor_helpers import format_ctypes_obj
            return format_ctypes_obj(obj, indent=indent, max_depth=max_depth)
        except Exception:
            pad = '  ' * indent
            return f"{pad}{repr(obj)}\n"

    def _format_value_for_table(self, val):
        """Return a short string suitable for the details table's value column."""
        try:
            from .monitor_helpers import format_value_for_table
            return format_value_for_table(val)
        except Exception:
            try:
                if val is None:
                    return '<unset>'
                return str(val)
            except Exception:
                return '<unrepresentable>'

    def _get_enum_items(self, class_name):
        """Return a list of (name, value) tuples for an enum class name, or None."""
        try:
            from .monitor_helpers import get_enum_items
            return get_enum_items(class_name)
        except Exception:
            return None

    def show_message_form(self, label: str, editable: bool = True):
        """Build an editable form for message `label` (A messages).

        The form is placed into `self.detail_form_container`. Existing form
        widgets are destroyed and rebuilt for the new message.
        """
        try:
            # Use the form container for showing message details; do not toggle the
            # tree visibility here. The DetailsPane places the form inside a
            # scrollable canvas so it remains visible while updating.
            # if same form is already shown, refresh widget values safely
            if getattr(self, 'current_form_label', None) == label and self.form_widgets:
                try:
                    # use the existing helper which fetches fresh wrapper and
                    # updates widgets without rebuilding the form
                    self._refresh_and_update_form()
                except Exception:
                    pass
                return

            mdb = self._get_message_db()
            if mdb is None:
                return
            try:
                msg_wrapper = mdb.getMessage(label)
            except Exception:
                allm = mdb.getAllMessages()
                msg_wrapper = allm.get(label)
            if not msg_wrapper:
                return
            msg = getattr(msg_wrapper, 'message', None)
            if msg is None:
                return

            # clear previous form only when we know we're going to build a new one
            for w in self.detail_form_container.winfo_children():
                try:
                    w.destroy()
                except Exception:
                    pass
            self.form_widgets = {}
            self.current_form_label = label

            # header with Apply button at top
            hdr = tk.Frame(self.detail_form_container)
            hdr.pack(fill=tk.X, padx=6, pady=(6,0))
            lbl_hdr = tk.Label(hdr, text=f"Edit message {label}", anchor=tk.W)
            lbl_hdr.pack(side=tk.LEFT)
            # For editable forms show Apply button, otherwise present a label
            if editable:
                apply_btn = tk.Button(hdr, text='Apply', command=lambda: self._apply_form_values(msg_wrapper))
                apply_btn.pack(side=tk.RIGHT, padx=6)
            else:
                tk.Label(hdr, text='Read-only', anchor=tk.E).pack(side=tk.RIGHT, padx=6)

            # recursive builder for fields
            frm = tk.Frame(self.detail_form_container)
            frm.pack(fill=tk.BOTH, expand=True, padx=6, pady=6)
            self._build_form_fields(frm, msg, prefix='', editable=editable)

            # show form container
            try:
                self.detail_form_container.pack(side=tk.LEFT, fill=tk.BOTH, expand=True)
            except Exception:
                pass
        except Exception as e:
            try:
                self.log.insert(tk.END, f"Error building form: {e}\n")
            except Exception:
                pass

    def _build_form_fields(self, parent, obj, prefix='', max_depth=3, _depth=0, editable=True):
        """Recursively create labeled widgets for public fields of obj."""
        if _depth > max_depth:
            return
        row = 0
        # helper to detect struct-like ctypes objects
        def _is_struct_like(v):
            if v is None:
                return False
            if isinstance(v, (int, float, str, bytes)):
                return False
            if callable(v):
                return False
            # ctypes.Structure expose _fields_
            if hasattr(v, '_fields_'):
                return True
            # objects with many public attributes are likely struct-like
            public = [n for n in dir(v) if not n.startswith('_')]
            if len(public) > 2:
                return True
            return False

        for name in [n for n in dir(obj) if not n.startswith('_')]:
            try:
                val = getattr(obj, name)
            except Exception:
                continue
            if callable(val):
                continue
            full = f"{prefix}.{name}" if prefix else name
            # Special-case: ctypes Union with a '.str' structure (bitfields)
            if hasattr(val, 'str') and _is_struct_like(getattr(val, 'str')):
                subfrm = ttk.LabelFrame(parent, text=name)
                subfrm.pack(fill=tk.X, padx=6, pady=4)
                # recurse into the .str sub-structure so fields become e.g. settings.spare
                try:
                    self._build_form_fields(subfrm, getattr(val, 'str'), prefix=full, max_depth=max_depth, _depth=_depth+1)
                except Exception:
                    pass
                continue

            # group nested structs (ctypes structs or objects with many public attrs)
            if _is_struct_like(val) and not (hasattr(val, 'raw') or hasattr(val, 'value')):
                subfrm = ttk.LabelFrame(parent, text=name)
                subfrm.pack(fill=tk.X, padx=6, pady=4)
                self._build_form_fields(subfrm, val, prefix=full, max_depth=max_depth, _depth=_depth+1)
                continue
            # create label + widget
            row_fr = tk.Frame(parent)
            row_fr.pack(fill=tk.X, padx=2, pady=1)
            lbl = tk.Label(row_fr, text=name, width=28, anchor=tk.W)
            lbl.pack(side=tk.LEFT)
            # enum choices?
            enum_items = None
            try:
                enum_items = self._get_enum_items(val.__class__.__name__)
            except Exception:
                enum_items = None
            widget = None
            if enum_items:
                # build combobox with names
                # show human-friendly label first, then numeric value
                choices = [f"{n} ({v})" for (n, v) in enum_items]
                var = tk.StringVar()
                # combobox is selectable for editable forms, otherwise disabled
                cb_state = 'readonly' if editable else 'disabled'
                cb = ttk.Combobox(row_fr, values=choices, textvariable=var, state=cb_state)
                # set current value
                try:
                    raw = int(getattr(val, 'raw', getattr(val, 'value', val)))
                    # find matching choice
                    sel = None
                    for (n, v) in enum_items:
                        if int(v) == raw:
                            sel = f"{n} ({v})"
                            break
                    if sel is not None:
                        var.set(sel)
                except Exception:
                    pass
                cb.pack(side=tk.RIGHT, fill=tk.X, expand=True)
                widget = ('combobox', cb, enum_items)
            else:
                # numeric or text entry
                var = tk.StringVar()
                try:
                    cur = getattr(val, 'raw', getattr(val, 'value', val))
                    if cur is None:
                        var.set('')
                    else:
                        var.set(str(cur))
                except Exception:
                    var.set('')
                ent = tk.Entry(row_fr, textvariable=var)
                # disable entry if not editable
                if not editable:
                    try:
                        ent.config(state='disabled')
                    except Exception:
                        pass
                ent.pack(side=tk.RIGHT, fill=tk.X, expand=True)
                widget = ('entry', ent)

            # register created widget for later updates; values will be filled
            # by `_update_form_values` when a message wrapper is available.
            try:
                self.form_widgets[full] = widget
            except Exception:
                pass

    def _apply_form_values(self, msg_wrapper):
        """Read widgets from `self.form_widgets` and apply values to message."""
        for full, widget in list(self.form_widgets.items()):
            try:
                if widget[0] == 'combobox':
                    cb = widget[1]
                    sel = cb.get()
                    if not sel:
                        continue
                    # sel like 'NAME (3)'; try to extract numeric value inside parentheses
                    try:
                        start = sel.rfind('(')
                        end = sel.rfind(')')
                        if start != -1 and end != -1 and end > start:
                            num = sel[start+1:end].strip()
                            val = int(num)
                        else:
                            # fallback to first token
                            num = sel.split()[0]
                            val = int(num)
                    except Exception:
                        val = sel
                else:
                    ent = widget[1]
                    txt = ent.get()
                    val = self._coerce_text_to_type(txt)
                # apply
                try:
                    self._apply_edit_to_msg(full, str(val), msg_wrapper)
                except Exception as e:
                    try:
                        self.log.insert(tk.END, f"Failed to set {full}: {e}\n")
                    except Exception:
                        pass
            except Exception:
                pass
        try:
            self.log.insert(tk.END, "Applied form values\n")
        except Exception:
            pass

    def _add_detail_row(self, name: str, value: str, accessor=None):
        """Insert or update a row in the details table (param -> value)."""
        try:
            # support hierarchical names separated by '.' or '/'
            def _ensure_hierarchy(full_name):
                parts = [p for p in full_name.replace('/', '.').split('.') if p != '']
                parent = ''
                acc = []
                for p in parts[:-1]:
                    acc.append(p)
                    key = '.'.join(acc)
                    if key in self.detail_rows:
                        parent = self.detail_rows[key]
                        continue
                    # create parent node with empty value
                    try:
                        iid = self.detail_tree.insert(parent, tk.END, values=(p, ''))
                        # ensure parent is expanded so nested fields remain visible
                        try:
                            self.detail_tree.item(iid, open=True)
                            self._always_open_parents[key] = True
                        except Exception:
                            pass
                        self.detail_rows[key] = iid
                        parent = iid
                    except Exception:
                        # fallback: try to insert at root
                        try:
                            iid = self.detail_tree.insert('', tk.END, values=(p, ''))
                            self.detail_rows[key] = iid
                            parent = iid
                        except Exception:
                            parent = ''
                leaf = parts[-1] if parts else full_name
                leaf_parent_key = '.'.join(parts[:-1]) if parts[:-1] else ''
                leaf_parent = self.detail_rows.get(leaf_parent_key, '')
                return leaf_parent, leaf

            if name in self.detail_rows:
                iid = self.detail_rows[name]
                try:
                    # keep the param column stable; show only the leaf label
                    leaf = name.split('.')[-1]
                    parent_key = '.'.join(name.replace('/', '.').split('.')[:-1])
                    if parent_key and parent_key in self.detail_rows:
                        disp = f"-> {leaf}"
                    else:
                        disp = leaf
                    self.detail_tree.item(iid, values=(disp, value))
                    # if this row represents a parent that we marked to remain open,
                    # ensure it's still expanded after value updates
                    try:
                        parent_key = name
                        if parent_key in self._always_open_parents:
                            self.detail_tree.item(iid, open=True)
                    except Exception:
                        pass
                    if accessor is not None:
                        self.detail_accessors[name] = accessor
                    return iid
                except Exception:
                    pass

            # insert hierarchical node
            parent_iid, leaf_label = _ensure_hierarchy(name)
            try:
                leaf_parent_key = '.'.join(name.replace('/', '.').split('.')[:-1])
                if leaf_parent_key:
                    disp_label = f"-> {leaf_label}"
                else:
                    disp_label = leaf_label
                iid = self.detail_tree.insert(parent_iid, tk.END, values=(disp_label, value))
                self.detail_rows[name] = iid
                if accessor is not None:
                    self.detail_accessors[name] = accessor
                return iid
            except Exception:
                try:
                    leaf_parent_key = '.'.join(name.replace('/', '.').split('.')[:-1])
                    if leaf_parent_key:
                        disp_label = f"-> {leaf_label}"
                    else:
                        disp_label = leaf_label
                    iid = self.detail_tree.insert('', tk.END, values=(disp_label, value))
                    self.detail_rows[name] = iid
                    if accessor is not None:
                        self.detail_accessors[name] = accessor
                    return iid
                except Exception:
                    return None
        except Exception:
            try:
                # best-effort: insert without tracking
                # best-effort hierarchical insert
                parent_iid, leaf_label = (lambda n: ('' , n))(name)
                try:
                    leaf_parent_key = '.'.join(name.replace('/', '.').split('.')[:-1])
                    if leaf_parent_key:
                        disp_label = f"-> {leaf_label}"
                    else:
                        disp_label = leaf_label
                    iid = self.detail_tree.insert(parent_iid, tk.END, values=(disp_label, str(value)))
                    if accessor is not None:
                        self.detail_accessors[name] = accessor
                    return iid
                except Exception:
                    return None
            except Exception:
                return None
    
    def _add_detail_rows_from_obj(self, prefix: str, obj, max_depth: int = 4, _depth: int = 0):
        """Recursively add detail rows for public fields of `obj`.

        - `prefix` is a string prepended to field names (e.g. 'param1').
        - Stops recursing after `max_depth` to avoid noisy dumps.
        - Uses `_format_value_for_table` and `_fmt_enum` to annotate enum-like values.
        """
        if _depth > max_depth:
            try:
                self._add_detail_row(prefix or '<value>', self._format_value_for_table(obj))
            except Exception:
                pass
            return

        if obj is None:
            try:
                self._add_detail_row(prefix or '<value>', '<None>')
            except Exception:
                pass
            return

        # primitive types
        if isinstance(obj, (int, float, str)):
            try:
                self._add_detail_row(prefix or '<value>', str(obj))
            except Exception:
                pass
            return

        # Enum-like or ctypes scalar handling
        def _is_struct_like_local(v):
            # heuristics similar to form builder: ctypes.Structure or many public attrs
            if v is None:
                return False
            if isinstance(v, (int, float, str, bytes)):
                return False
            if hasattr(v, '_fields_'):
                return True
            public = [n for n in dir(v) if not n.startswith('_')]
            if len(public) > 2:
                return True
            return False

        if hasattr(obj, 'raw') or hasattr(obj, 'value'):
            # If the object also looks like a struct (has nested fields), recurse
            if _is_struct_like_local(obj):
                # fall through to attribute iteration to expand nested fields
                pass
            else:
                try:
                    s = None
                    try:
                        raw = int(getattr(obj, 'raw')) if hasattr(obj, 'raw') else int(getattr(obj, 'value'))
                        s = self._fmt_enum(raw, [obj.__class__.__name__])
                    except Exception:
                        try:
                            s = str(getattr(obj, 'raw', getattr(obj, 'value', obj)))
                        except Exception:
                            s = repr(obj)
                    self._add_detail_row(prefix or obj.__class__.__name__, s)
                except Exception:
                    try:
                        self._add_detail_row(prefix or '<value>', repr(obj))
                    except Exception:
                        pass
                return

        # dict-like
        try:
            if isinstance(obj, dict):
                for k, v in obj.items():
                    name = f"{prefix}.{k}" if prefix else str(k)
                    self._add_detail_rows_from_obj(name, v, max_depth=max_depth, _depth=_depth+1)
                return
        except Exception:
            pass

        # sequence
        try:
            if isinstance(obj, (list, tuple)):
                for i, v in enumerate(obj):
                    name = f"{prefix}[{i}]" if prefix else f"[{i}]"
                    self._add_detail_rows_from_obj(name, v, max_depth=max_depth, _depth=_depth+1)
                return
        except Exception:
            pass

        # otherwise iterate public attributes
        import inspect
        names = [n for n in dir(obj) if not n.startswith('_')]
        for n in names:
            try:
                v = getattr(obj, n)
            except Exception:
                continue
            field_name = f"{prefix}.{n}" if prefix else n

            # If attribute is a ctypes Union with a '.str' bitfield, expand it
            try:
                if hasattr(v, 'str') and (hasattr(getattr(v, 'str'), '__dict__') or hasattr(getattr(v, 'str'), '_fields_')):
                    try:
                        self._add_detail_rows_from_obj(field_name, getattr(v, 'str'), max_depth=max_depth, _depth=_depth+1)
                        continue
                    except Exception:
                        pass
            except Exception:
                pass

            # If callable, try to call zero-arg getters (get_*/is_*) to obtain a value
            if callable(v):
                called = False
                try:
                    sig = inspect.signature(v)
                    if len(sig.parameters) == 0:
                        try:
                            val = v()
                            self._add_detail_row(field_name, self._format_value_for_table(val))
                            called = True
                        except Exception:
                            called = False
                except Exception:
                    # fallback: attempt to call and ignore errors
                    try:
                        val = v()
                        self._add_detail_row(field_name, self._format_value_for_table(val))
                        called = True
                    except Exception:
                        called = False
                if called:
                    continue
                # otherwise skip arbitrary callables
                continue

            # Primitive or scalar-like values
            if isinstance(v, (int, float, str)) or hasattr(v, 'raw') or hasattr(v, 'value'):
                try:
                    self._add_detail_row(field_name, self._format_value_for_table(v))
                except Exception:
                    pass
            else:
                # Recurse into nested objects
                try:
                    self._add_detail_rows_from_obj(field_name, v, max_depth=max_depth, _depth=_depth+1)
                except Exception:
                    pass

    def on_init(self):
        # On-demand import/creation of the connection manager when the user requests initialization.
        if self.manager is None:
            try:
                from pybusmonitor1553.core.connection_manager import get_manager
                self.manager = get_manager()
                self.import_error = None
            except Exception as e:
                # record import/bind error and show diagnostics
                self.import_error = str(e)
                try:
                    self.open_diagnostics(auto=False)
                except Exception:
                    pass
                try:
                    self.update_status()
                except Exception:
                    pass
                return

        try:
            self.manager.init_library()
            try:
                self.logger.info("Initialization completed.")
            except Exception:
                try:
                    self.log.insert(tk.END, "Initialization completed.\n")
                except Exception:
                    pass
            self.refresh_messages()
            try:
                self.start_btn.config(state=tk.NORMAL)
                self.stop_btn.config(state=tk.DISABLED)
            except Exception:
                pass
            try:
                self.update_status()
            except Exception:
                pass
        except Exception as e:
            messagebox.showerror("Error", str(e))

    def on_start(self):
        if getattr(self, 'import_error', None):
            messagebox.showerror("Error", f"Connection library error: {self.import_error}")
            return
        try:
            self.manager.start()
            try:
                self.logger.info("Start send/receive")
            except Exception:
                self.log.insert(tk.END, "Start send/receive\n")
            if not self.update_loop_running:
                self.update_loop_running = True
                threading.Thread(target=self.periodic_update, daemon=True).start()
            try:
                self.update_status()
            except Exception:
                pass
        except Exception as e:
            messagebox.showerror("Error", str(e))
        try:
            self.start_btn.config(state=tk.DISABLED)
            self.stop_btn.config(state=tk.NORMAL)
        except Exception:
            pass

    def on_stop(self):
        if getattr(self, 'import_error', None):
            # nothing to stop
            try:
                self.logger.info("Stop requested (no connection active)")
            except Exception:
                self.log.insert(tk.END, "Stop requested (no connection active)\n")
            return
        self.manager.stop()
        try:
            self.logger.info("Stop requested")
        except Exception:
            self.log.insert(tk.END, "Stop requested\n")
        try:
            self.update_status()
        except Exception:
            pass
        try:
            self.start_btn.config(state=tk.NORMAL)
            self.stop_btn.config(state=tk.DISABLED)
        except Exception:
            pass

    def open_diagnostics(self, auto: bool = False):
        # Diagnostics dialog with error details and Retry.
        # When auto=True (startup auto-open), do not force modal grab so
        # the GUI can finish initialization without blocking.
            dlg = tk.Toplevel(self.master)
            dlg.title("Diagnostics")
            dlg.transient(self.master)
            if not auto:
                try:
                    dlg.grab_set()
                except Exception:
                    pass
            try:
                dlg.focus_force()
            except Exception:
                pass

            # Center the dialog over the main window
            try:
                self.master.update_idletasks()
                mx = self.master.winfo_rootx()
                my = self.master.winfo_rooty()
                mw = self.master.winfo_width()
                mh = self.master.winfo_height()
                w = 420
                h = 140
                x = mx + max(0, (mw - w) // 2)
                y = my + max(0, (mh - h) // 2)
                dlg.geometry(f"{w}x{h}+{x}+{y}")
            except Exception:
                pass

            tk.Label(dlg, text="Connection diagnostics", font=(None, 12, 'bold')).pack(padx=12, pady=(8,4))

            # Determine likely UDP port (allow override via env)
            try:
                port = int(os.environ.get('PYBM_RX_PORT', '61553'))
            except Exception:
                port = 61553

            # Simple user-facing message
            msg_text = f"The UDP port {port} is likely already in use by another application.\nClose this application to free the port."
            lbl = tk.Label(dlg, text=msg_text, wraplength=380, justify=tk.LEFT)
            lbl.pack(padx=12, pady=(4,8), expand=True, fill=tk.BOTH)

            btn_fr = tk.Frame(dlg)
            btn_fr.pack(pady=8)
            close_btn = tk.Button(btn_fr, text="Close", command=lambda: self.master.destroy())
            close_btn.pack(side=tk.LEFT, padx=6)

    def _retry_and_update(self, dialog):
        # Attempt to reload connection manager and clear import_error if successful
        try:
            import importlib, sys
            # reload connection manager module to re-run import logic
            if 'pybusmonitor1553.core.connection_manager' in sys.modules:
                cm = sys.modules['pybusmonitor1553.core.connection_manager']
                importlib.reload(cm)
            else:
                cm = importlib.import_module('pybusmonitor1553.core.connection_manager')
            # try to obtain manager
            get_manager = getattr(cm, 'get_manager', None)
            if get_manager is None:
                raise RuntimeError('connection_manager missing get_manager')
            self.manager = get_manager()
            self.import_error = None
            try:
                self.init_btn.config(state=tk.NORMAL)
                self.start_btn.config(state=tk.NORMAL)
            except Exception:
                pass
            try:
                messagebox.showinfo('Diagnostics', 'Connection modules reloaded successfully.')
            except Exception:
                pass
            try:
                dialog.destroy()
            except Exception:
                pass
            try:
                self.update_status()
            except Exception:
                pass
        except Exception as e:
            # update dialog text with latest error
            try:
                for w in dialog.winfo_children():
                    if isinstance(w, tk.Text):
                        w.config(state=tk.NORMAL)
                        w.delete('1.0', tk.END)
                        w.insert(tk.END, f"Retry failed: {e}\n\nSuggested actions:\n- Close other app using UDP port 61553\n- Update PYBM_RX_PORT/PYBM_RX_IP if needed\n- Restart this app after freeing the port\n")
                        w.config(state=tk.DISABLED)
                        break
            except Exception:
                pass
            try:
                self.update_status()
            except Exception:
                pass

    def refresh_messages(self):
        # Incremental tree update: preserve selection and avoid full redraw
        try:
            mdb = self._get_message_db()
            if mdb is None:
                return
            msgs = mdb.getAllMessages()
            lbl_filter = self.filter_entry.get().strip().lower()
            pmin = pmax = None
            try:
                if self.period_min.get().strip() != "":
                    pmin = float(self.period_min.get().strip())
                if self.period_max.get().strip() != "":
                    pmax = float(self.period_max.get().strip())
            except Exception:
                pmin = pmax = None

            # preserve current selection label (if any)
            cur_sel = None
            sel = self.tree.selection()
            if sel:
                try:
                    cur_item = sel[0]
                    cur_vals = self.tree.item(cur_item, 'values')
                    if cur_vals:
                        cur_sel = cur_vals[0]
                except Exception:
                    cur_sel = None

            # mark seen labels to remove stale rows afterwards
            seen = set()

            for k, v in msgs.items():
                if lbl_filter and lbl_filter not in k.lower():
                    continue

                # compute display fields
                try:
                    cw_raw = getattr(v.head.cw, 'raw', None)
                    wc = getattr(v.head.cw.str, 'wc', '')
                except Exception:
                    cw_raw = None
                    wc = ''
                try:
                    sw_raw = getattr(v.head, 'sw', '')
                except Exception:
                    sw_raw = ''
                num = getattr(v, 'sent_count', getattr(v, 'size', ''))
                try:
                    errs = getattr(v.head, 'errcode', '')
                except Exception:
                    errs = ''
                period = getattr(v, '_time_ms', None)
                if period is None:
                    freq = getattr(v, 'freq', None)
                    if freq:
                        period = 1000.0 / freq
                if period is not None and pmin is not None and period < pmin:
                    continue
                if period is not None and pmax is not None and period > pmax:
                    continue
                try:
                    mc = getattr(v, 'recv_count', '')
                except Exception:
                    mc = ''

                values = (k, hex(cw_raw) if cw_raw is not None else '', sw_raw, num, errs, f"{period:.3f}" if period else '', wc, mc)

                # update existing row or insert new one
                if k in self._tree_items and self._tree_items[k] in self.tree.get_children(''):
                    try:
                        self.tree.item(self._tree_items[k], values=values)
                    except Exception:
                        # fallback: recreate item
                        try:
                            self.tree.delete(self._tree_items[k])
                        except Exception:
                            pass
                        iid = self.tree.insert('', tk.END, values=values)
                        self._tree_items[k] = iid
                else:
                    iid = self.tree.insert('', tk.END, values=values)
                    self._tree_items[k] = iid

                seen.add(k)

            # remove stale items not present anymore
            stale = [lbl for lbl in list(self._tree_items.keys()) if lbl not in seen]
            for lbl in stale:
                try:
                    self.tree.delete(self._tree_items[lbl])
                except Exception:
                    pass
                del self._tree_items[lbl]

            # restore selection if possible
            if cur_sel and cur_sel in self._tree_items:
                try:
                    self.tree.selection_set(self._tree_items[cur_sel])
                except Exception:
                    pass

        except Exception:
            pass

    def on_tree_select(self, event):
        sel = self.tree.selection()
        if not sel:
            return
        item = sel[0]
        vals = self.tree.item(item, 'values')
        if not vals:
            return
        label = vals[0]
        self.show_message_detail(label)

    def show_message_detail(self, label: str):
        # build table for this label; detail_tree will be populated and updated
        # Do not clear the form here — only clear when we know we'll show
        # an error message or rebuild the details. Clearing before the
        # MessageDB lookup causes the UI to briefly show then disappear
        # if the lookup fails during a refresh.
        self.detail_rows = {}
        self.detail_selected_label = label
        try:
            mdb = self._get_message_db()
            if mdb is None:
                # clear any previous form/tree content before showing diagnostic
                try:
                    for w in getattr(self, 'detail_form_container', []).winfo_children():
                        try:
                            w.destroy()
                        except Exception:
                            pass
                except Exception:
                    pass
                try:
                    self.detail_tree.insert('', tk.END, values=("Message DB not available", "Open Diagnostics for details."))
                except Exception:
                    pass
                try:
                    self.log.insert(tk.END, "Message DB not available (import error). Open Diagnostics for details.\n")
                except Exception:
                    pass
                return
            # Try direct lookup first
            try:
                msg_wrapper = mdb.getMessage(label)
            except Exception:
                # Try alternative access patterns: getAllMessages() dict lookup
                try:
                    allm = mdb.getAllMessages()
                    # exact key
                    if label in allm:
                        msg_wrapper = allm[label]
                    else:
                        # case-insensitive match or startswith
                        found = None
                        for k in allm.keys():
                            if k.lower() == label.lower() or k.startswith(label):
                                found = allm[k]
                                break
                        msg_wrapper = found
                except Exception:
                    msg_wrapper = None
        except Exception as e:
            # log diagnostic to the UI log and detail pane
            try:
                self.log.insert(tk.END, f"show_message_detail lookup error: {e}\n")
            except Exception:
                pass
            self.detail_text.insert(tk.END, f"Message {label} not found in MessageDB (error).\n")
            return

        if not msg_wrapper:
            # clear any existing form before showing 'No data'
            try:
                for w in getattr(self, 'detail_form_container', []).winfo_children():
                    try:
                        w.destroy()
                    except Exception:
                        pass
            except Exception:
                pass
            try:
                self.detail_tree.insert('', tk.END, values=("No data", f"{label}"))
            except Exception:
                pass
            try:
                self.log.insert(tk.END, f"No wrapper found for {label} in MessageDB\n")
            except Exception:
                pass
            return
            try:
                self.log.insert(tk.END, f"No wrapper found for {label} in MessageDB\n")
            except Exception:
                pass
            return

        # The actual ctypes message instance
        msg = getattr(msg_wrapper, 'message', None)
        # store current wrapper for edit/apply
        try:
            self.current_msg_wrapper = msg_wrapper
        except Exception:
            self.current_msg_wrapper = None

        # If this is an A message, show editable form instead of tree
        try:
            if label and str(label).upper().startswith('A'):
                try:
                    self.show_message_form(label)
                    return
                except Exception:
                    pass
        except Exception:
            pass
        # store current wrapper for edit/apply
        try:
            self.current_msg_wrapper = msg_wrapper
        except Exception:
            self.current_msg_wrapper = None
        if msg is None:
            # Clear any existing form before showing 'No message'
            try:
                for w in getattr(self, 'detail_form_container', []).winfo_children():
                    try:
                        w.destroy()
                    except Exception:
                        pass
            except Exception:
                pass
            try:
                self.detail_tree.insert('', tk.END, values=("No message", "<empty>"))
            except Exception:
                pass
            try:
                self.log.insert(tk.END, f"Wrapper for {label} has no 'message' attribute\n")
            except Exception:
                pass
            return

        # Use the same form renderer for B messages (read-only) to avoid toggling
        # between tree and form and to keep the UI stable. This will build a
        # non-editable form for the message so values can be observed live.
        try:
            self.show_message_form(label, editable=False)
        except Exception:
            try:
                self.log.insert(tk.END, f"Failed to render form for {label}\n")
            except Exception:
                pass
        return

    def periodic_update(self):
        while self.manager.is_running():
            try:
                self.refresh_messages()
            except Exception:
                pass
            # schedule UI updates (do UI work on main thread)
            try:
                now = time.time()
                if now - getattr(self, '_last_detail_update', 0) >= 1.0:
                    self._last_detail_update = now
                    try:
                        # update detail values and form on UI thread
                        try:
                            self.after(0, self.update_detail_values)
                        except Exception:
                            self.update_detail_values()
                        try:
                            # refresh and update form if visible
                            self.after(0, self._refresh_and_update_form)
                        except Exception:
                            self._refresh_and_update_form()
                    except Exception:
                        pass
            except Exception:
                pass
            time.sleep(0.5)
        self.update_loop_running = False
        try:
            self.update_status()
        except Exception:
            pass

    def _flash_item(self, iid, duration_ms=700):
        """Temporarily apply highlight tag to a tree item, then remove it."""
        try:
            # apply tag
            self.detail_tree.item(iid, tags=('changed',))
            # cancel previous timer if any
            prev = self._flash_items.get(iid)
            if prev:
                try:
                    self.after_cancel(prev)
                except Exception:
                    pass
            # schedule removal
            after_id = self.after(duration_ms, lambda: self._clear_flash(iid))
            self._flash_items[iid] = after_id
        except Exception:
            pass

    def _clear_flash(self, iid):
        try:
            # remove tag
            self.detail_tree.item(iid, tags=())
            # clear scheduled id
            if iid in self._flash_items:
                del self._flash_items[iid]
        except Exception:
            pass

    def update_detail_values(self):
        """Refresh only the values for the currently selected detail rows (throttled)."""
        label = getattr(self, 'detail_selected_label', None)
        if not label:
            return
        # diagnostic logging toggle
        DEBUG_DETAIL_UPDATES = True
        try:
            mdb = self._get_message_db()
            if mdb is None:
                return
            try:
                msg_wrapper = mdb.getMessage(label)
            except Exception:
                allm = mdb.getAllMessages()
                msg_wrapper = allm.get(label) or None
            if not msg_wrapper:
                return
            msg = getattr(msg_wrapper, 'message', None)
            if msg is None:
                return
        except Exception:
            return

        # iterate rows and update via accessor if provided
        for name, iid in list(self.detail_rows.items()):
            try:
                # skip header rows
                if str(name).startswith('#'):
                    continue
                accessor = self.detail_accessors.get(name)
                if callable(accessor):
                    try:
                        val = accessor()
                    except Exception:
                        # fallback: try attribute path resolution against msg
                        val = None
                else:
                    # try to resolve dotted attribute path against msg
                    val = None
                    try:
                        if '.' in name:
                            parts = name.split('.')
                            cur = msg
                            for p in parts:
                                if '[' in p and p.endswith(']'):
                                    # index access
                                    key, idx = p[:-1].split('[')
                                    if key:
                                        cur = getattr(cur, key)
                                    cur = cur[int(idx)]
                                else:
                                    cur = getattr(cur, p)
                            val = cur
                        else:
                            val = getattr(msg, name)
                    except Exception:
                        val = None

                new_str = self._format_value_for_table(val)
                cur_vals = self.detail_tree.item(iid, 'values')
                cur_val = ''
                try:
                    cur_val = cur_vals[1]
                except Exception:
                    cur_val = ''
                if DEBUG_DETAIL_UPDATES:
                    try:
                        self.log.insert(tk.END, f"Detail update check {label}:{name} cur='{cur_val}' new='{new_str}'\n")
                    except Exception:
                        pass
                if new_str != cur_val:
                    try:
                        # update display value keeping only the leaf name in the param column
                        try:
                            leaf_label = name.split('.')[-1]
                        except Exception:
                            leaf_label = name
                        parent_key = '.'.join(name.replace('/', '.').split('.')[:-1])
                        if parent_key and parent_key in self.detail_rows:
                            disp = f"-> {leaf_label}"
                        else:
                            disp = leaf_label
                        self.detail_tree.item(iid, values=(disp, new_str))
                        # flash the changed row
                        self._flash_item(iid)
                        if DEBUG_DETAIL_UPDATES:
                            try:
                                self.log.insert(tk.END, f"Detail updated {label}:{name} -> {new_str}\n")
                            except Exception:
                                pass
                    except Exception:
                        pass
            except Exception:
                pass

    def _refresh_and_update_form(self):
        """Fetch fresh wrapper for current form label and update form widgets."""
        try:
            label = getattr(self, 'current_form_label', None)
            if not label:
                return
            mdb = self._get_message_db()
            if mdb is None:
                return
            try:
                wrapper = mdb.getMessage(label)
            except Exception:
                allm = mdb.getAllMessages()
                wrapper = allm.get(label)
            if not wrapper:
                return
            # update stored wrapper and refresh widgets
            self.current_msg_wrapper = wrapper
            try:
                self._update_form_values(wrapper)
            except Exception:
                pass
        except Exception:
            pass

    def _update_form_values(self, msg_wrapper):
        """Update displayed values in the form widgets from `msg_wrapper` without rebuilding widgets."""
        try:
            msg = getattr(msg_wrapper, 'message', None)
            if msg is None:
                return
            for full, widget in list(self.form_widgets.items()):
                try:
                    # resolve the value from msg
                    val = None
                    try:
                        parts = [p for p in full.replace('/', '.').split('.') if p != '']
                        cur = msg
                        for p in parts:
                            if '[' in p and p.endswith(']'):
                                key, idx = p[:-1].split('[')
                                if key:
                                    cur = getattr(cur, key)
                                cur = cur[int(idx)]
                            else:
                                cur = getattr(cur, p)
                        val = getattr(cur, 'raw', getattr(cur, 'value', cur))
                    except Exception:
                        val = None

                    if widget[0] == 'combobox':
                        cb = widget[1]
                        enum_items = widget[2]
                        try:
                            if val is None:
                                cb.set('')
                            else:
                                raw = int(val)
                                sel = None
                                for (n, v) in enum_items:
                                    if int(v) == raw:
                                        sel = f"{n} ({v})"
                                        break
                                if sel is not None:
                                    cb.set(sel)
                                else:
                                    cb.set('')
                        except Exception:
                            try:
                                cb.set('')
                            except Exception:
                                pass
                    else:
                        ent = widget[1]
                        try:
                            ent.delete(0, tk.END)
                            if val is None:
                                ent.insert(0, '')
                            else:
                                ent.insert(0, str(val))
                        except Exception:
                            pass
                except Exception:
                    pass
        except Exception:
            pass

    def on_detail_double_click(self, event):
        # Start inline edit of the clicked value cell
        try:
            region = self.detail_tree.identify('region', event.x, event.y)
            if region != 'cell':
                return
            rowid = self.detail_tree.identify_row(event.y)
            col = self.detail_tree.identify_column(event.x)
            if not rowid or col != '#2':
                return
            # get bbox for the cell
            bbox = self.detail_tree.bbox(rowid, col)
            if not bbox:
                return
            x, y, w, h = bbox
            abs_x = self.detail_tree.winfo_rootx() + x
            abs_y = self.detail_tree.winfo_rooty() + y
            cur_vals = self.detail_tree.item(rowid, 'values')
            cur_text = ''
            try:
                cur_text = cur_vals[1]
            except Exception:
                cur_text = ''
            # create a transient Entry widget over the cell (as child of master)
            self._edit_var = tk.StringVar(value=str(cur_text))
            self._edit_entry = tk.Entry(self.master, textvariable=self._edit_var)
            # place relative to tree (use winfo) - use place on root
            rx = self.detail_tree.winfo_rootx() - self.master.winfo_rootx() + x
            ry = self.detail_tree.winfo_rooty() - self.master.winfo_rooty() + y
            self._edit_entry.place(x=rx, y=ry, width=w, height=h)
            self._edit_entry.focus_set()
            self._editing_target = (rowid, col)
            self._edit_entry.bind('<Return>', lambda e: self._commit_edit())
            self._edit_entry.bind('<Escape>', lambda e: self._cancel_edit())
            self._edit_entry.bind('<FocusOut>', lambda e: self._cancel_edit())
        except Exception:
            pass

    def _commit_edit(self):
        try:
            if not getattr(self, '_editing_target', None):
                return
            rowid, col = self._editing_target
            new_text = self._edit_var.get()
            # update displayed value (keep param label unchanged)
            cur_vals = self.detail_tree.item(rowid, 'values')
            label = cur_vals[0] if cur_vals else ''
            try:
                self.detail_tree.item(rowid, values=(label, new_text))
            except Exception:
                pass
            # find the detail_rows reverse mapping to get the full dotted name
            full_name = None
            for k, iid in self.detail_rows.items():
                if iid == rowid:
                    full_name = k
                    break
            # apply the new value to the underlying message if available
            if full_name and getattr(self, 'current_msg_wrapper', None):
                try:
                    self._apply_edit_to_msg(full_name, new_text, self.current_msg_wrapper)
                    try:
                        self.log.insert(tk.END, f"Applied edit {full_name} = {new_text}\n")
                    except Exception:
                        pass
                except Exception as e:
                    try:
                        self.log.insert(tk.END, f"Failed to apply edit: {e}\n")
                    except Exception:
                        pass
            try:
                self._edit_entry.destroy()
            except Exception:
                pass
            self._editing_target = None
            self._edit_entry = None
            self._edit_var = None
        except Exception:
            pass

    def _cancel_edit(self):
        try:
            if getattr(self, '_edit_entry', None):
                try:
                    self._edit_entry.destroy()
                except Exception:
                    pass
            self._editing_target = None
            self._edit_entry = None
            self._edit_var = None
        except Exception:
            pass

    def _apply_edit_to_msg(self, full_name: str, text_value: str, msg_wrapper):
        """Resolve `full_name` against `msg_wrapper.message` and set the value.

        Handles dotted names and simple indexed parts. For ctypes fields, tries
        to set `.raw` or `.value` if present; otherwise uses setattr.
        Attempts int then float conversion; falls back to string.
        """
        msg = getattr(msg_wrapper, 'message', None)
        if msg is None:
            raise RuntimeError('No message object to apply to')

        # resolve path parts
        parts = [p for p in full_name.replace('/', '.').split('.') if p != '']
        cur = msg
        for p in parts[:-1]:
            # handle index like foo[0]
            if '[' in p and p.endswith(']'):
                key, idx = p[:-1].split('[')
                if key:
                    cur = getattr(cur, key)
                cur = cur[int(idx)]
            else:
                cur = getattr(cur, p)

        last = parts[-1]
        # handle array index on last
        target_parent = cur
        target_attr = last
        if '[' in last and last.endswith(']'):
            key, idx = last[:-1].split('[')
            if key:
                target_parent = getattr(cur, key)
            idx = int(idx)
            # assign into sequence
            # convert text_value
            val = self._coerce_text_to_type(text_value)
            try:
                target_parent[idx] = val
                return
            except Exception:
                # try setattr on element
                target_parent = target_parent[idx]
                target_attr = None

        # now set on target_parent.target_attr
        val = self._coerce_text_to_type(text_value)
        # prefer .raw or .value
        if target_attr and hasattr(target_parent, target_attr):
            targ = getattr(target_parent, target_attr)
            if hasattr(targ, 'raw'):
                try:
                    targ.raw = val
                    return
                except Exception:
                    pass
            if hasattr(targ, 'value'):
                try:
                    targ.value = val
                    return
                except Exception:
                    pass
            # fallback setattr
            try:
                setattr(target_parent, target_attr, val)
                return
            except Exception:
                raise
        else:
            # if no attribute, try setting on parent directly
            try:
                setattr(target_parent, target_attr, val)
                return
            except Exception:
                # last resort: raise
                raise

    def _coerce_text_to_type(self, text: str):
        # try int, then float, then strip
        try:
            from .monitor_helpers import coerce_text_to_type
            return coerce_text_to_type(text)
        except Exception:
            try:
                if text.startswith('0x'):
                    return int(text, 16)
            except Exception:
                pass
            try:
                return int(text)
            except Exception:
                try:
                    return float(text)
                except Exception:
                    return text

    def on_send_now(self):
        """Attempt to send the currently selected message immediately.

        Tries several manager APIs (`send_now`, `send_message`, `send`) and
        falls back to logging if none available.
        """
        try:
            label = getattr(self, 'detail_selected_label', None)
            if not label:
                try:
                    self.log.insert(tk.END, "No message selected to send\n")
                except Exception:
                    pass
                return
            mgr = getattr(self, 'manager', None)
            if mgr is None:
                try:
                    self.log.insert(tk.END, "Manager not available to send message\n")
                except Exception:
                    pass
                return
            # try known method names
            for name in ('send_now', 'send_message', 'send'):
                fn = getattr(mgr, name, None)
                if callable(fn):
                    try:
                        fn(label)
                        try:
                            self.log.insert(tk.END, f"Sent message {label} via {name}\n")
                        except Exception:
                            pass
                        return
                    except Exception:
                        pass
            try:
                self.log.insert(tk.END, f"Manager does not expose send API; modified message saved for scheduled send: {label}\n")
            except Exception:
                pass
        except Exception:
            pass

    def update_status(self):
        try:
            if getattr(self, 'import_error', None):
                try:
                    port = int(os.environ.get('PYBM_RX_PORT', '61553'))
                except Exception:
                    port = 61553
                # left pane shows connection state
                try:
                    self.status_left.config(text=f"Disconnected: UDP {port}", fg="red")
                except Exception:
                    pass
                return
            if self.manager is not None:
                # check for running state
                try:
                    is_running = getattr(self.manager, 'is_running', None)
                    if callable(is_running):
                        running = is_running()
                    else:
                        running = bool(getattr(self.manager, 'running', False))
                    if running:
                        try:
                            self.status_left.config(text="Connected (running)", fg="green")
                        except Exception:
                            pass
                        return
                except Exception:
                    pass
            # default
            try:
                self.status_left.config(text="Ready (not running)", fg="orange")
            except Exception:
                pass
        except Exception:
            try:
                self.status_left.config(text="Status unknown", fg="black")
            except Exception:
                pass


def main():
    root = tk.Tk()
    root.title("PyBusMonitor1553 - Monitor")
    root.geometry("1024x768")
    app = MonitorApp(master=root)
    def on_closing():
        try:
            if getattr(app, 'logger_system', None):
                app.logger_system.shutdown()
        except Exception:
            pass
        try:
            if getattr(app, '_resource_monitor', None):
                try:
                    app._resource_monitor.stop()
                except Exception:
                    pass
        except Exception:
            pass
        root.destroy()

    root.protocol("WM_DELETE_WINDOW", on_closing)
    app.mainloop()


if __name__ == '__main__':
    main()