# scripts/guardrails.py
from __future__ import annotations

import json
import re
from pathlib import Path
from typing import Any, Dict, List, Optional, Tuple, Set


def _read_json(path: str) -> Dict[str, Any]:
    return json.loads(Path(path).read_text(encoding="utf-8"))


class TargetRegistry:
    def __init__(self, data: Dict[str, Any]):
        self.data = data or {}
        self.canonical = self.data.get("canonical", {})
        self.points = self.data.get("points", {})
        self.synonyms = self.data.get("synonyms", {})
        self.mim_default_by_mg = self.data.get("mim_default_by_mg", {})

        # Build quick lookup of allowed devices per mg (union of all groups)
        self.allowed_by_mg: Dict[str, Set[str]] = {}
        for group, mg_map in self.canonical.items():
            for mg, devices in mg_map.items():
                self.allowed_by_mg.setdefault(mg, set()).update(devices)

        # Flatten device synonyms
        self.dev_syn = self.synonyms.get("device", {})
        self.point_syn = self.synonyms.get("point", {})
        self.mim_syn = self.synonyms.get("mim", {})

    @classmethod
    def from_json(cls, path: str) -> "TargetRegistry":
        return cls(_read_json(path))

    def allowed_devices(self, mg: Optional[str]) -> Set[str]:
        if not mg:
            return set()
        return self.allowed_by_mg.get(mg, set())

    def canonicalize_mim(self, mim: Optional[str]) -> Optional[str]:
        if mim is None:
            return None
        m = self.mim_syn.get(mim, mim)
        m = m.upper()
        if re.fullmatch(r"MIM[1-4]", m):
            return m
        return None  # unknown MIM label

    def canonicalize_point(self, point: str) -> str:
        return self.point_syn.get(point, point)

    def canonicalize_device(self, dev: str, mg: Optional[str]) -> str:
        # direct synonym
        dev2 = self.dev_syn.get(dev, dev)

        # If device has a dot (like mg1.cap_01), squash using mg+core
        if "." in dev2 and mg:
            core = dev2.split(".")[-1]
            candidate = f"{mg}{core}"
            # Try mg-prefixed candidate first
            if candidate in self.allowed_devices(mg):
                return candidate
            # Try synonym mapping of the core
            dev3 = self.dev_syn.get(core, core)
            candidate2 = f"{mg}{dev3}"
            if candidate2 in self.allowed_devices(mg):
                return candidate2

        # If device lacks mg prefix but mg is present, and mg+dev is allowed, use it
        if mg and not dev2.startswith(mg):
            cand = f"{mg}{dev2}"
            if cand in self.allowed_devices(mg):
                return cand

        # If already allowed, keep it
        if mg and dev2 in self.allowed_devices(mg):
            return dev2

        # Fall back to synonym again (idempotent) or original
        return dev2

    def pick_default_mim(self, mg: Optional[str]) -> Optional[str]:
        if mg is None:
            return None
        return self.mim_default_by_mg.get(mg)


def augment_prompt_with_allowlist(instruction: str, reg: TargetRegistry) -> str:
    # Append a short allow-list hint (kept compact)
    def bucket_preview(mg: str) -> str:
        items = sorted(list(reg.allowed_devices(mg)))[:8]
        return f"{mg}: {', '.join(items)}" if items else ""

    hints = []
    for mg in ("mg1", "mg2", "mg3", "substation", "unmapped"):
        s = bucket_preview(mg)
        if s:
            hints.append(s)

    if hints:
        instruction += (
            "\nAllowed device names (examples):\n"
            + "\n".join(hints)
            + "\nUse exactly one dot in `name`: [optional MIM].<device>.<point>\n"
        )
    return instruction


def _parse_name(name: str) -> Tuple[Optional[str], Optional[str], Optional[str]]:
    # Accepts:
    #  MIM1.device.point
    #  device.point
    # If multiple dots exist (bad), we capture best-effort pieces.
    parts = name.split(".")
    if len(parts) >= 3 and re.fullmatch(r"MIM[1-4]", parts[0]):
        mim = parts[0]
        point = parts[-1]
        device = ".".join(parts[1:-1])  # may contain dots → caller will clean
        return mim, device, point
    elif len(parts) >= 2:
        point = parts[-1]
        device = ".".join(parts[:-1])   # may contain dots → caller will clean
        return None, device, point
    return None, None, None


def _build_name(mim: Optional[str], device: str, point: str) -> str:
    if mim:
        return f"{mim}.{device}.{point}"
    return f"{device}.{point}"


def _is_switch_point(point: str) -> bool:
    return point in {"status", "switchA", "switchB", "switchC"}


def _normalize_openclose(item: Dict[str, Any]) -> None:
    op = item.get("op")
    point = item.get("point")
    if op in {"open", "close"} or _is_switch_point(point):
        # Normalize values to uppercase OPEN/CLOSED
        av = item.get("attack_value")
        rv = item.get("real_value")
        if isinstance(av, str):
            item["attack_value"] = av.upper()
        if isinstance(rv, str):
            item["real_value"] = rv.upper()
        # If op=open and attack_value missing → OPEN
        if op == "open" and not item.get("attack_value"):
            item["attack_value"] = "OPEN"
        if op == "close" and not item.get("attack_value"):
            item["attack_value"] = "CLOSED"
        # Default real_value if absent (reasonable default)
        if not item.get("real_value"):
            item["real_value"] = "CLOSED" if item["attack_value"] == "OPEN" else "OPEN"


def validate_and_fix_attackplan(
    ap: Dict[str, Any],
    reg: TargetRegistry,
    strict: bool = False,
    autofix: bool = True,
    cutoff: float = 0.92,  # unused, kept for interface stability
) -> Tuple[Dict[str, Any], List[str]]:
    notes: List[str] = []

    if not isinstance(ap, dict):
        notes.append("attack plan is not a dict")
        return ap, notes

    # Fix top-level mim.selected using first item's scope if needed
    plan: List[Dict[str, Any]] = ap.get("plan") or []
    if plan:
        scope0 = plan[0].get("scope", {})
        mg0 = scope0.get("mg")
        mim0 = scope0.get("mim")
        mim0 = reg.canonicalize_mim(mim0) or reg.pick_default_mim(mg0)
        # Constrain selected to a single MIM when we have one
        if mim0:
            ap.setdefault("mim", {})
            ap["mim"]["active"] = True
            ap["mim"]["selected"] = [mim0]

    new_plan: List[Dict[str, Any]] = []

    for it in plan:
        scope = it.get("scope", {}) or {}
        mg = scope.get("mg")
        mim = reg.canonicalize_mim(scope.get("mim")) or reg.pick_default_mim(mg)

        # Parse and canonicalize name parts
        name = it.get("name", "")
        mim_in, dev_raw, point_raw = _parse_name(name)
        point = reg.canonicalize_point(point_raw) if point_raw else point_raw

        # Choose mim priority: explicit in scope, else in name
        mim_final = mim or reg.canonicalize_mim(mim_in)

        # Canonicalize device using mg + synonyms
        dev_final = reg.canonicalize_device(dev_raw or "", mg)

        # If still unknown and strict, drop
        if strict and mg and dev_final not in reg.allowed_devices(mg):
            notes.append(f"dropped unknown device for mg={mg}: {dev_raw}")
            continue

        # Rebuild name with exactly one dot in device segment
        if dev_final and point:
            it["name"] = _build_name(mim_final, dev_final, point)

        # Update scope.mim to the resolved one
        if mim_final:
            it.setdefault("scope", {})
            it["scope"]["mim"] = mim_final

        # Normalize switch/OPEN-CLOSED values
        _normalize_openclose(it)

        new_plan.append(it)

    ap["plan"] = new_plan
    return ap, notes