"""Network profile control surface; backend access is restricted to a forced SSH command."""
from __future__ import annotations
import json, os, secrets, subprocess, time
from flask import Flask, flash, jsonify, redirect, render_template, request, session, url_for

app = Flask(__name__)
app.secret_key = os.environ["SESSION_SECRET"]
app.config.update(SESSION_COOKIE_HTTPONLY=True, SESSION_COOKIE_SAMESITE="Strict", SESSION_COOKIE_SECURE=True)

PROFILES = {
    "strict": {"label": "Strikt", "ch": 0.5, "vpn": 0.5, "color": "#ff667d"},
    "standard": {"label": "Standard", "ch": 1.0, "vpn": 1.0, "color": "#a88dff"},
    "relaxed": {"label": "Entspannt", "ch": 5.0, "vpn": 5.0, "color": "#32d6a3"},
    "open": {"label": "Off-Peak", "ch": 10.0, "vpn": 10.0, "color": "#26c6da"},
}
_CACHE = {"at": 0.0, "data": None}

def rpc(command: str, timeout: int = 25):
    p = subprocess.run(
        ["ssh", "-o", "BatchMode=yes", "-o", "ConnectTimeout=8", "edge-maint", command],
        capture_output=True, text=True, timeout=timeout,
    )
    raw = p.stdout.strip()
    try:
        data = json.loads(raw) if raw else {}
    except json.JSONDecodeError:
        data = {"ok": False, "error": (p.stderr or raw or "invalid response")[:300]}
    if p.returncode and data.get("ok") is not False:
        data = {"ok": False, "error": (p.stderr or raw or f"rpc exit {p.returncode}")[:300]}
    return data

def get_state(force=False):
    now = time.monotonic()
    if not force and _CACHE["data"] is not None and now - _CACHE["at"] < 3:
        return _CACHE["data"]
    try:
        data = rpc("state")
    except Exception as exc:
        data = {"ok": False, "error": str(exc)[:300], "limits": {}, "tc": {}, "services": {}, "policy": {}, "ipsets": {}}
    _CACHE.update(at=now, data=data)
    return data

def csrf_token():
    token = session.get("csrf")
    if not token:
        token = session["csrf"] = secrets.token_urlsafe(32)
    return token

app.jinja_env.globals["csrf_token"] = csrf_token

@app.before_request
def protect_post():
    if request.method == "POST" and not secrets.compare_digest(request.form.get("csrf", ""), session.get("csrf", "invalid")):
        return "invalid request token", 400

@app.get("/")
def dashboard():
    state = get_state()
    return render_template("dashboard.html", state=state, profiles=PROFILES)

@app.post("/profile/<name>")
def apply_profile(name):
    profile = PROFILES.get(name)
    if not profile:
        flash("Unbekanntes Profil", "error")
        return redirect(url_for("dashboard"))
    result = rpc(f"set-limits {profile['ch']} {profile['vpn']}")
    _CACHE["data"] = None
    flash(f"Profil {profile['label']} aktiviert" if result.get("ok") else f"Fehler: {result.get('error','unbekannt')}", "success" if result.get("ok") else "error")
    return redirect(url_for("dashboard"))

@app.post("/limits")
def custom_limits():
    try:
        ch = float(request.form["ch"]); vpn = float(request.form["vpn"])
        if not 0.1 <= ch <= 100 or not 0.1 <= vpn <= 100:
            raise ValueError
    except (KeyError, ValueError):
        flash("Limits müssen zwischen 0,1 und 100 Mbit liegen", "error")
        return redirect(url_for("dashboard"))
    result = rpc(f"set-limits {ch:g} {vpn:g}")
    _CACHE["data"] = None
    flash("Benutzerdefinierte Limits gesetzt" if result.get("ok") else f"Fehler: {result.get('error','unbekannt')}", "success" if result.get("ok") else "error")
    return redirect(url_for("dashboard"))

@app.post("/policy")
def policy():
    mode = request.form.get("mode", "")
    try:
        min_sessions = int(request.form.get("min_sessions", "2"))
        block_minutes = int(request.form.get("block_minutes", "10"))
        if mode not in {"off", "monitor", "block"} or not 2 <= min_sessions <= 8 or not 1 <= block_minutes <= 1440:
            raise ValueError
    except ValueError:
        flash("Ungültige Policy-Werte", "error")
        return redirect(url_for("dashboard"))
    result = rpc(f"set-policy {mode} {min_sessions} {block_minutes}")
    _CACHE["data"] = None
    flash("Session-Policy aktualisiert" if result.get("ok") else f"Fehler: {result.get('error','unbekannt')}", "success" if result.get("ok") else "error")
    return redirect(url_for("dashboard"))

@app.post("/maintenance/<action>")
def maintenance(action):
    mapping = {
        "refresh": "limiter refresh", "start": "limiter start", "stop": "limiter stop",
        "worker": "restart worker", "admin": "restart admin",
    }
    command = mapping.get(action)
    if not command:
        return "unknown action", 404
    result = rpc(command)
    _CACHE["data"] = None
    flash(f"Aktion {action} gestartet" if result.get("ok") else f"Fehler: {result.get('error','unbekannt')}", "success" if result.get("ok") else "error")
    return redirect(url_for("dashboard"))

@app.get("/api/status")
def api_status():
    return jsonify(get_state())

@app.get("/health")
def health():
    state = get_state()
    return jsonify({"ok": bool(state.get("ok")), "backend": "reachable" if state else "unreachable"}), 200 if state.get("ok") else 503