import os
import json
import google.generativeai as genai
from typing import Dict, Any

class NarrativeService:
    def __init__(self, model_name: str = "gemini-2.5-flash"):
        self.api_key = os.getenv("GEMINI_API_KEY")
        if not self.api_key:
            print("WARNING: GEMINI_API_KEY not found. LLM features will fail.")
        else:
            genai.configure(api_key=self.api_key)

        self.model_name = model_name

    def generate_narrative(self, stats_json: Dict[str, Any]) -> Dict[str, str]:
        if not self.api_key:
            return {"error": "Missing API Key"}

        prompt = f"""
You are a witty, insightful, and slightly snarky music critic analyzing a user's listening history. 
Below is a JSON summary of their listening data. 

Your goal is to generate a report that feels like a 'Spotify Wrapped' but deeper and more honest.

Please output your response in strict JSON format with the following keys:
1. "vibe_check": (String) 2-3 paragraphs describing their overall listening personality.
2. "patterns": (List of Strings) 3-5 specific observations based on the data (e.g., "You listen to sad music on Tuesdays", "Your Whiplash Score is high").
3. "persona": (String) A creative label for the user (e.g., "The Genre Chameleon", "Nostalgic Dad-Rocker", "Algorithm Victim").
4. "roast": (String) A playful, harmlessly mean roast about their taste (1-2 sentences).
5. "era_insight": (String) A specific comment on their 'Musical Age' and 'Nostalgia Gap'.

GUIDELINES:
- **Use the Metrics:** Do not just say "You like pop." Say "Your Mainstream Score of 85% suggests you live on the Top 40."
- **Whiplash Score:** If 'whiplash' > 20, comment on their chaotic transitions.
- **Hipster Score:** If 'hipster_score' > 50, call them pretentious; if < 10, call them basic.
- **Comparison:** Use the 'comparison' block to mention if they are listening more/less or if their mood (valence/energy) has shifted.
- **Tone:** Conversational, fun, slightly judgmental but good-natured.

DATA:
{json.dumps(stats_json, indent=2)}

OUTPUT (JSON):
"""
        try:
            model = genai.GenerativeModel(self.model_name)
            response = model.generate_content(prompt)

            # Clean up response to ensure valid JSON
            text = response.text.strip()
            if text.startswith("```json"):
                text = text.replace("```json", "").replace("```", "")
            elif text.startswith("```"):
                 text = text.replace("```", "")

            return json.loads(text)

        except Exception as e:
            return {"error": str(e), "raw_response": "Error generating narrative."}