"""
api_service.py
Thin wrapper around the Railway backend API.
All HTTP calls to the remote backend go through here.
"""

import requests
import time
from flask import current_app

# ── Cooldown tracking ────────────────────────────────────────
_plate_last_seen: dict[str, float] = {}


import os

def _base_url() -> str:
    try:
        from flask import current_app
        return current_app.config["BACKEND_API_URL"].rstrip("/")
    except:
        return os.getenv("BACKEND_API_URL", "https://pant0x-ain-el-aql-backend.hf.space").rstrip("/")


def _headers(token: str | None = None) -> dict:
    h = {"Accept": "application/json"}
    hf_token = os.getenv("HF_TOKEN")
    
    # Hugging Face needs this to let the request through the Private Space proxy
    if hf_token:
        h["Authorization"] = f"Bearer {hf_token}"
        
    # Backend will read the user session from this new header
    if token:
        h["X-Supabase-Auth"] = f"Bearer {token}"
        
    return h


def normalize_arabic_plate(text: str) -> str:
    """Converts Hindi digits to Western digits and handles formatting."""
    if not text: return ""
    hindi_to_western = {
        '٠': '0', '١': '1', '٢': '2', '٣': '3', '٤': '4',
        '٥': '5', '٦': '6', '٧': '7', '٨': '8', '٩': '9'
    }
    
    # Convert digits
    res = ""
    for char in text:
        res += hindi_to_western.get(char, char)
        
    if '|' in res:
        parts = res.split('|')
        letters = parts[0].strip()
        numbers = parts[1].strip().replace(" ", "")
        # Reverse numbers for correct LTR display in the browser
        return f"{letters} | {numbers[::-1]}"
    
    return res


def extract_match_key(text: str) -> str:
    """
    Extracts alphanumeric characters and sorts them (Letters then Numbers)
    to ensure 'SQR 777' and '777 SQR' generate the same key 'SQR777'.
    """
    if not text: return ""
    text = text.replace(" ", "").replace("|", "").replace("-", "")
    
    import re
    letters = "".join(re.findall(r'[a-zA-Z\u0600-\u06FF]+', text))
    numbers = "".join(re.findall(r'[0-9]+', text))
    
    # Egyptian system usually prefers Letters then Numbers
    return f"{letters}{numbers}"


# ── Health ───────────────────────────────────────────────────
def check_health() -> dict:
    try:
        r = requests.get(f"{_base_url()}/health", timeout=5)
        return r.json()
    except Exception as e:
        return {"status": "error", "detail": str(e)}


def check_supabase_health() -> dict:
    try:
        r = requests.get(f"{_base_url()}/supabase/health", timeout=5)
        return r.json()
    except Exception as e:
        return {"status": "error", "detail": str(e)}


# ── Auth ─────────────────────────────────────────────────────
def login(identifier: str, password: str) -> dict:
    """POST /auth/login  →  returns user + session."""
    try:
        r = requests.post(
            f"{_base_url()}/auth/login",
            json={"identifier": identifier, "password": password},
            headers=_headers(),
            timeout=30,
        )
        
        if r.status_code != 200:
            try:
                error_msg = r.json().get("detail", r.json().get("error", "Unknown error"))
            except:
                error_msg = f"Error {r.status_code}: {r.text[:100]}"
            return {"error": error_msg}
            
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def register(payload: dict) -> dict:
    """POST /auth/register"""
    try:
        r = requests.post(
            f"{_base_url()}/auth/register",
            json=payload,
            headers=_headers(),
            timeout=10,
        )
        return r.json()
    except Exception as e:
        return {"error": str(e)}


# ── Predict / OCR ────────────────────────────────────────────
def predict(image_bytes: bytes, filename: str, event_type: str = "entry",
            location: str = "OPERA", token: str | None = None) -> dict:
    """
    POST /process-image (Railway)  →  send image for OCR.
    Then optionally call /gate/decision to get registration/gate status.
    """
    try:
        # 1. Get OCR from the Main Engine
        # Backend expects 'image' field for the file, and 'camera_source'
        files = {"image": (filename, image_bytes, "image/jpeg")}
        data = {
            "camera_source": location,
            "parking_location": location,
            "event_type": event_type
        }
        
        ocr_resp = requests.post(
            f"{_base_url()}/predict",
            files=files,
            data=data,
            headers=_headers(token) if token else _headers(),
            timeout=30,
        )
        
        if ocr_resp.status_code != 200:
            return {"error": f"Backend OCR failed: {ocr_resp.text[:100]}"}
            
        resp = ocr_resp.json()
        
        # 2. Map OCR results (Robust mapping)
        det = resp.get("detection") or resp
        urls = resp.get("urls") or resp.get("images") or {}
        
        # Try different possible plate field names including new backend format
        plate_info_dict = resp.get("plate_info", {})
        plate_text = det.get("plate_text") or det.get("plate_ar") or det.get("plate") or plate_info_dict.get("arabic") or ""
        en_text = det.get("en_text") or det.get("plate_en") or plate_info_dict.get("english") or ""
        
        if plate_text or en_text:
            normalized_ar = normalize_arabic_plate(plate_text)
            match_key = extract_match_key(en_text) or extract_match_key(normalized_ar)
            
            # Use the registration info directly if the backend already provided it
            # Different backends might use 'app_registration' or top-level 'matched'
            reg_info = resp.get("app_registration") or resp.get("registration") or {}
            is_registered = False
            if isinstance(reg_info, dict):
                is_registered = reg_info.get("is_registered", resp.get("matched", False))
            elif isinstance(reg_info, bool):
                is_registered = reg_info

            resp["matched"] = is_registered
            resp["plate_text_ar"] = normalized_ar
            resp["plate_info"] = {
                "plate_ar": normalized_ar,
                "plate_en": en_text,
                "plate_key": match_key,
                "confidence": det.get("confidence", det.get("score", 0))
            }
            
            # Map Images
            admin_page_data = resp.get("admin_page", {})
            if "admin_page" not in resp:
                resp["admin_page"] = {}
                
            # If backend returns base64, create a data URL
            if admin_page_data.get("annotated_image_base64"):
                b64 = admin_page_data["annotated_image_base64"]
                # Sometimes it might already have the prefix
                if b64.startswith("data:"):
                    resp["admin_page"]["processed_image_url"] = b64
                else:
                    resp["admin_page"]["processed_image_url"] = f"data:image/jpeg;base64,{b64}"
            else:
                resp["admin_page"]["processed_image_url"] = urls.get("processed") or urls.get("annotated") or ""
                
            resp["admin_page"]["raw_image_url"] = urls.get("raw") or urls.get("original") or ""

            # 3. Call Gate Decision (Business Logic)
            if "gate_decision" not in resp:
                try:
                    decision_payload = {
                        "plate_key": resp["plate_info"]["plate_key"],
                        "event_type": event_type,
                        "parking_location": location
                    }
                    dr = requests.post(
                        f"{_base_url()}/gate/decision",
                        json=decision_payload,
                        headers=_headers(token) if token else _headers(),
                        timeout=10
                    )
                    if dr.status_code == 200:
                        decision_data = dr.json()
                        resp.update(decision_data)
                except Exception as e:
                    resp["backend_warning"] = f"Gate decision failed: {str(e)}"
                
        return resp
    except Exception as e:
        return {"error": str(e)}


def is_on_cooldown(plate_key: str) -> bool:
    """Returns True if plate was scanned within PLATE_COOLDOWN_SECONDS."""
    cooldown = current_app.config["PLATE_COOLDOWN_SECONDS"]
    now = time.time()
    if plate_key in _plate_last_seen:
        if now - _plate_last_seen[plate_key] < cooldown:
            return True
    _plate_last_seen[plate_key] = now
    return False


# ── Parking / Events  (staff endpoints) ─────────────────────
def get_entered_cars(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/events/entered-cars",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_inside_cars(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/events/inside-cars",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_left_cars(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/events/left-cars",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_leaving_soon(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/events/leaving-cars-within-5-minutes",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_new_cars(token: str) -> dict:
    """GET /events/new-cars  — staff-only real-time polling feed."""
    try:
        r = requests.get(f"{_base_url()}/events/new-cars",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_parking_history(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/parking/history",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_all_users(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/users",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_parking_locations(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/parking/locations",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_parking_occupancy(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/parking/occupancy",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


# ── Vehicles ─────────────────────────────────────────────────
def get_my_vehicles(token: str) -> dict:
    try:
        r = requests.get(f"{_base_url()}/vehicles/my",
                         headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def add_vehicle(token: str, payload: dict) -> dict:
    try:
        r = requests.post(f"{_base_url()}/vehicles/add",
                          json=payload, headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def edit_vehicle(token: str, vehicle_id: str, payload: dict) -> dict:
    try:
        r = requests.put(f"{_base_url()}/vehicles/{vehicle_id}",
                         json=payload, headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def delete_vehicle(token: str, vehicle_id: str) -> dict:
    try:
        r = requests.delete(f"{_base_url()}/vehicles/{vehicle_id}",
                            headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


# ── Profile ──────────────────────────────────────────────────
def update_profile(token: str, payload: dict) -> dict:
    try:
        r = requests.put(f"{_base_url()}/profile/update",
                         json=payload, headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


# ── Payments ─────────────────────────────────────────────────
def confirm_cash_payment(token: str, payload: dict) -> dict:
    """POST /payments/manual/cash-confirm  — staff-only."""
    try:
        r = requests.post(f"{_base_url()}/payments/manual/cash-confirm",
                          json=payload, headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


def get_gate_decision(token: str, payload: dict) -> dict:
    try:
        r = requests.post(f"{_base_url()}/gate/decision",
                          json=payload, headers=_headers(token), timeout=30)
        return r.json()
    except Exception as e:
        return {"error": str(e)}


# ── Gate hardware (ESP) ──────────────────────────────────────
def trigger_gate_open(plate: str = "", location: str = "OPERA") -> dict:
    """Queue a gate-open command on the cloud backend for ESP32 devices to poll."""
    try:
        r = requests.post(
            f"{_base_url()}/gate/trigger",
            json={
                "parking_location": location,
                "duration_seconds": 10,
                "plate": plate,
            },
            timeout=5,
        )
        return {"status": "sent", "backend_response": r.json()}
    except Exception as e:
        return {"status": "error", "detail": str(e)}


# ── Admin maintenance ────────────────────────────────────────
def weekly_refresh(token: str) -> dict:
    try:
        r = requests.post(f"{_base_url()}/admin/maintenance/weekly-refresh",
                          headers=_headers(token), timeout=15)
        return r.json()
    except Exception as e:
        return {"error": str(e)}