import os
import json
import redis
import requests
import logging
import datetime # Import datetime for dynamic date

logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')

# 🌐 Configuration from Environment Variables
REDIS_URL = os.environ.get("UPSTASH_REDIS_URL", "redis://localhost:6379")
WHATSAPP_API_URL = os.environ.get("WHATSAPP_API_URL", "https://api.gupshup.io/wa/api/v1/msg") 
WHATSAPP_TOKEN = os.environ.get("WHATSAPP_TOKEN")
WHATSAPP_TO_NUMBER = os.environ.get("WHATSAPP_TO_NUMBER", "353899495777")  
GUPSHUP_SOURCE_NUMBER = os.environ.get("GUPSHUP_SOURCE_NUMBER")  
GUPSHUP_APP_NAME = os.environ.get("GUPSHUP_APP_NAME")  

# ✅ Redis connection
try:
    redis_client = redis.Redis.from_url(REDIS_URL, decode_responses=True)
    redis_client.ping() 
    logging.info("Redis client connected successfully.")
except Exception as e:
    logging.error(f"❌ Failed to connect to Redis: {e}")
    raise

# --- New: Topic mapping for display names and emojis ---
TOPIC_DISPLAY_MAP = {
    "india": {"name": "India", "emoji": "🇮🇳"},
    "world": {"name": "World", "emoji": "🌍"},
    "tech": {"name": "Technology", "emoji": "🧠"}, 
    "finance": {"name": "Business & Markets", "emoji": "💰"}, 
    "sports": {"name": "Sports", "emoji": "🏆"}, 
}

# 🧾 Fetch and format headlines
# UPDATED: To match the exact "NUSE DAILY" format and new item format
def fetch_cached_headlines() -> str:
    try:
        raw = redis_client.get("daily_news_feed_cache") 
        if not raw:
            logging.warning("⚠️ No detailed news headlines found in cache.")
            return "⚠️ No daily headlines found in cache."
        data = json.loads(raw)
    except Exception as e:
        logging.error(f"❌ Error reading from Redis: {e}")
        return f"❌ Error reading from Redis: {e}"

    # Get current date for the header
    today = datetime.date.today()
    formatted_date = today.strftime("%B %d, %Y")

    message_parts = []

    # Header section
    message_parts.append(f"Nuse Daily - {formatted_date}")
    message_parts.append("") 

    # Iterate through topics in a defined order for consistent output
    for topic_key, display_info in TOPIC_DISPLAY_MAP.items(): 
        stories_for_topic = data.get(topic_key) 
        
        if stories_for_topic: 
            message_parts.append(f"{display_info['emoji']} *{display_info['name']}*")
            
            sorted_story_ids = sorted(stories_for_topic.keys(), key=int) 

            for ref_id in sorted_story_ids:
                item = stories_for_topic[ref_id]
                summary = item.get("summary", "") 
                description = item.get("explanation", "") 
                
                # <<< UPDATED: Item format to "1. <summary> - <explanation>" >>>
                # Using U+2007 (Figure Space) for alignment
                message_parts.append(f"\u2007{ref_id}. \u2007{summary} - {description}")
            message_parts.append("") 

    # Footer section
    message_parts.append("")
    message_parts.append("Curated by Nuse.")

    return "\n".join(message_parts)

# 📤 Send via Gupshup WhatsApp API
def send_to_whatsapp(message_text: str, destination_number: str) -> dict: 
    # Validate critical environment variables
    if not WHATSAPP_TOKEN or \
       not GUPSHUP_SOURCE_NUMBER or \
       not GUPSHUP_APP_NAME:
        error_msg = "❌ Missing one or more critical WhatsApp API environment variables (WHATSAPP_TOKEN, GUPSHUP_SOURCE_NUMBER, GUPSHUP_APP_NAME)."
        logging.error(error_msg)
        return {"status": "failed", "error": error_msg, "code": 500}
    
    if not destination_number:
        error_msg = "❌ Destination number cannot be empty."
        logging.error(error_msg)
        return {"status": "failed", "error": error_msg, "code": 400}


    headers = {
        "Content-Type": "application/x-www-form-urlencoded",
        "apikey": WHATSAPP_TOKEN, 
        "Cache-Control": "no-cache",
        "accept": "application/json" 
    }

    whatsapp_message_content = {
        "type": "text",
        "text": message_text 
    }
    
    payload = {
        "channel": "whatsapp",
        "source": GUPSHUP_SOURCE_NUMBER,
        "destination": destination_number,
        "src.name": GUPSHUP_APP_NAME,
        "message": message_text,
        "disablePreview": False, 
        "encode": False          
    }

    try:
        logging.info(f"Attempting to send standard text WhatsApp message to {destination_number}, {GUPSHUP_SOURCE_NUMBER}, {GUPSHUP_APP_NAME}, {WHATSAPP_TOKEN} via Gupshup. API URL: {WHATSAPP_API_URL} and message text is {message_text}")
        response = requests.post(
            WHATSAPP_API_URL, 
            headers=headers,
            data=payload, 
        )
        response.raise_for_status() 

        return {"status": "success", "details": response.json()}
    except requests.exceptions.RequestException as e:
        logging.error(f"❌ Failed to send WhatsApp message: {e}")
        return {"status": "failed", "error": str(e), "code": e.response.status_code if e.response else 500}
    except Exception as e:
        logging.error(f"❌ An unexpected error occurred during WhatsApp send: {e}")
        return {"status": "failed", "error": str(e), "code": 500}