# components/store/users.py
import os
import time
import json
import logging
from typing import Any, Dict, List, Optional

import redis

# Reuse your Upstash Redis
REDIS_URL = os.environ.get("UPSTASH_REDIS_URL", "redis://localhost:6379")
redis_client = redis.Redis.from_url(REDIS_URL, decode_responses=True)

# Key helpers
def _user_key(wa_id: str) -> str:
    return f"user:{wa_id}"

def _prefs_key(wa_id: str) -> str:
    return f"user:{wa_id}:prefs"

# ------------- Core CRUD -------------

def get_user(wa_id: str) -> Optional[Dict[str, Any]]:
    try:
        data = redis_client.hgetall(_user_key(wa_id))
        if not data:
            return None
        # Normalize types
        if "created_at" in data:
            data["created_at"] = float(data["created_at"])
        if "updated_at" in data:
            data["updated_at"] = float(data["updated_at"])
        if "last_seen" in data:
            data["last_seen"] = float(data["last_seen"])
        if "last_msg_ts" in data:
            data["last_msg_ts"] = float(data["last_msg_ts"])
        # Preferences
        prefs = redis_client.get(_prefs_key(wa_id))
        data["preferences"] = json.loads(prefs) if prefs else {"topics": [], "regions": [], "time": None}
        return data
    except Exception as e:
        logging.exception(f"get_user error for {wa_id}: {e}")
        return None


def upsert_user(
    wa_id: str,
    display_name: Optional[str] = None,
    phone_e164: Optional[str] = None,
    source: str = "whatsapp",
    extra: Optional[Dict[str, Any]] = None,
) -> Dict[str, Any]:
    """
    Create or update a user profile. Non-destructive: only updates provided fields.
    """
    now = time.time()
    key = _user_key(wa_id)
    # pipe for atomic-ish writes
    p = redis_client.pipeline()
    try:
        exists = redis_client.exists(key)
        fields = {
            "wa_id": wa_id,
            "source": source,
            "updated_at": now,
        }
        if display_name is not None:
            fields["display_name"] = display_name
        if phone_e164 is not None:
            fields["phone_e164"] = phone_e164
        if extra:
            # store a small JSON for misc signals (e.g., locale)
            fields["extra_json"] = json.dumps(extra)[:4096]

        if not exists:
            fields["created_at"] = now
            fields.setdefault("consent", "unknown")  # 'opt_in'|'opt_out'|'unknown'
        p.hset(key, mapping={k: str(v) for k, v in fields.items()})
        p.execute()
        user = get_user(wa_id) or {}
        return user
    except Exception as e:
        logging.exception(f"upsert_user error for {wa_id}: {e}")
        return {"wa_id": wa_id, "error": str(e)}


def set_last_seen(wa_id: str, ts: Optional[float] = None) -> None:
    try:
        redis_client.hset(_user_key(wa_id), mapping={
            "last_seen": str(ts if ts is not None else time.time())
        })
    except Exception as e:
        logging.exception(f"set_last_seen error for {wa_id}: {e}")


def record_inbound_message(wa_id: str, message_id: str, ts: Optional[float] = None) -> None:
    try:
        redis_client.hset(_user_key(wa_id), mapping={
            "last_msg_id": message_id,
            "last_msg_ts": str(ts if ts is not None else time.time())
        })
    except Exception as e:
        logging.exception(f"record_inbound_message error for {wa_id}: {e}")


def set_preferences(wa_id: str, topics: Optional[List[str]] = None,
                    regions: Optional[List[str]] = None, time_pref: Optional[str] = None) -> Dict[str, Any]:
    """
    Persist user preferences as a small JSON blob.
    - topics: e.g., ["india","finance"]
    - regions: e.g., ["IN","EU"]
    - time_pref: e.g., "09:00"
    """
    try:
        current = get_user(wa_id) or {}
        prefs = current.get("preferences", {}) or {}
        if topics is not None:
            prefs["topics"] = [t.strip().lower() for t in topics if t.strip()]
        if regions is not None:
            prefs["regions"] = [r.strip().upper() for r in regions if r.strip()]
        if time_pref is not None:
            prefs["time"] = time_pref
        redis_client.set(_prefs_key(wa_id), json.dumps(prefs))
        # Touch updated_at
        redis_client.hset(_user_key(wa_id), mapping={"updated_at": str(time.time())})
        current["preferences"] = prefs
        return current
    except Exception as e:
        logging.exception(f"set_preferences error for {wa_id}: {e}")
        return {"wa_id": wa_id, "error": str(e)}

# ------------- Webhook helpers -------------

def _extract_contact_name(payload: Dict[str, Any]) -> Optional[str]:
    """
    Try multiple shapes:
    value.contacts[0].profile.name
    """
    try:
        for entry in payload.get("entry", []):
            for change in entry.get("changes", []):
                if change.get("field") != "messages":
                    continue
                val = change.get("value", {}) or {}
                contacts = val.get("contacts", []) or []
                if contacts:
                    prof = contacts[0].get("profile", {}) or {}
                    name = prof.get("name")
                    if name:
                        return name
    except Exception:
        pass
    return None


def ensure_user_from_webhook(payload: Dict[str, Any], from_number: str, message_id: Optional[str]) -> Dict[str, Any]:
    """
    Ensure the user exists/updated using webhook payload signals.
    - from_number: WhatsApp 'from' (wa_id / E.164)
    - message_id: wamid... (for last message stamping)
    """
    display_name = _extract_contact_name(payload)
    user = upsert_user(
        wa_id=from_number,
        display_name=display_name,
        phone_e164=from_number,
        source="whatsapp",
        extra=None,
    )
    set_last_seen(from_number)
    if message_id:
        record_inbound_message(from_number, message_id)
    return user