# app/gui/can_panel.py
from __future__ import annotations
import json, subprocess, tkinter as tk
from tkinter import ttk, messagebox
from app.can import (
    list_can_ifaces, link_up, link_down, link_state, link_kind, have_cap_netadmin
)

class CanPanel:
    """Fixes CAN- & Responder-Panel (oben links)."""
    def __init__(self, parent, responder, initial_iface: str, initial_resp_id: int,
                 initial_timeout_ms: int, initial_bitrate: int, on_rebind_iface=None):
        self.responder = responder
        self.on_rebind_iface = on_rebind_iface or (lambda iface: None)

        self.frame = ttk.LabelFrame(parent, text="CAN & Settings", padding=8)
        for i in range(3): self.frame.columnconfigure(i, weight=1)

        # Interface
        ttk.Label(self.frame, text="Interface").grid(row=0, column=0, sticky="w")
        self.iface_var = tk.StringVar(value=initial_iface)
        self.iface_dd  = ttk.Combobox(self.frame, textvariable=self.iface_var,
                                      values=list_can_ifaces() or [initial_iface],
                                      state="readonly", width=14)
        self.iface_dd.grid(row=0, column=1, sticky="ew", padx=(6,0))
        ttk.Button(self.frame, text="Refresh", command=self._refresh_ifaces).grid(row=0, column=2, sticky="w")

        # RESP-ID
        ttk.Label(self.frame, text="RESP-ID (hex)").grid(row=1, column=0, sticky="w")
        self.resp_var = tk.StringVar(value=f"0x{initial_resp_id:03X}")
        ttk.Entry(self.frame, textvariable=self.resp_var, width=10).grid(row=1, column=1, sticky="w", padx=(6,0))

        # Timeout
        ttk.Label(self.frame, text="Timeout (ms)").grid(row=2, column=0, sticky="w")
        self.to_var = tk.IntVar(value=int(initial_timeout_ms))
        ttk.Spinbox(self.frame, from_=10, to=5000, increment=10, textvariable=self.to_var, width=10)\
            .grid(row=2, column=1, sticky="w", padx=(6,0))

        # Bitrate
        ttk.Label(self.frame, text="Bitrate").grid(row=3, column=0, sticky="w")
        self.br_var = tk.IntVar(value=int(initial_bitrate))
        ttk.Spinbox(self.frame, from_=20000, to=1000000, increment=10000, textvariable=self.br_var, width=12)\
            .grid(row=3, column=1, sticky="w", padx=(6,0))

        self.set_params = tk.BooleanVar(value=True)
        ttk.Checkbutton(self.frame, text="Bitrate beim UP setzen", variable=self.set_params)\
            .grid(row=3, column=2, sticky="w")

        self.kind_label = ttk.Label(self.frame, text=f"Kind: {link_kind(initial_iface)}", style="Small.TLabel")
        self.kind_label.grid(row=4, column=0, columnspan=3, sticky="w", pady=(4,0))

        # Buttons
        btns = ttk.Frame(self.frame); btns.grid(row=5, column=0, columnspan=3, sticky="ew", pady=(8,0))
        ttk.Button(btns, text="Link UP", command=self._do_link_up).grid(row=0, column=0, sticky="w")
        ttk.Button(btns, text="Link DOWN", command=self._do_link_down).grid(row=0, column=1, sticky="w", padx=(6,0))
        ttk.Button(btns, text="Responder Rebind", command=self._do_rebind).grid(row=0, column=2, sticky="w", padx=(12,0))

        ttk.Label(self.frame, text=f"CAP_NET_ADMIN: {'yes' if have_cap_netadmin() else 'no'}",
                  style="Small.TLabel").grid(row=6, column=0, columnspan=3, sticky="w", pady=(6,0))

    # ---- actions ----
    def _refresh_ifaces(self):
        lst = list_can_ifaces()
        if not lst:
            messagebox.showwarning("Interfaces", "Keine can*/vcan* Interfaces gefunden.")
            return
        self.iface_dd.config(values=lst)

    def _do_link_up(self):
        iface = self.iface_var.get()
        try:
            self.kind_label.config(text=f"Kind: {link_kind(iface)}")
            if link_state(iface) == "UP":
                messagebox.showinfo("CAN", f"{iface} ist bereits UP"); return
            link_up(iface, bitrate=self.br_var.get(), fd=False, set_params=self.set_params.get())
            try:
                out = subprocess.check_output(["ip","-details","-json","link","show",iface], text=True)
                info = json.loads(out)[0]
                bt = (info.get("linkinfo", {}) or {}).get("info_data", {}).get("bittiming") or {}
                br = bt.get("bitrate"); sp = bt.get("sample-point")
                if br:
                    messagebox.showinfo("CAN", f"{iface} ist UP @ {br} bit/s (SP {sp})")
            except Exception:
                pass
        except Exception as e:
            messagebox.showerror("CAN", f"Link UP fehlgeschlagen:\n{e}")

    def _do_link_down(self):
        iface = self.iface_var.get()
        try:
            if link_state(iface) == "DOWN":
                messagebox.showinfo("CAN", f"{iface} ist bereits DOWN"); return
            link_down(iface); messagebox.showinfo("CAN", f"{iface} ist DOWN")
        except Exception as e:
            messagebox.showerror("CAN", f"Link DOWN fehlgeschlagen:\n{e}")

    def _do_rebind(self):
        iface = self.iface_var.get()
        try:
            new_resp = int(self.resp_var.get(), 16)
        except Exception:
            messagebox.showerror("RESP-ID", "Bitte gültige Hex-Zahl, z.B. 0x7E8"); return
        try:
            self.responder.rebind(interface=iface, resp_id=new_resp, timeout_ms=self.to_var.get())
            self.on_rebind_iface(iface)  # TraceView umhängen
            messagebox.showinfo("CAN", f"Responder neu gebunden: {iface}, RESP 0x{new_resp:03X}")
        except Exception as e:
            messagebox.showerror("CAN", f"Rebind fehlgeschlagen:\n{e}")