Fix matplotlib dir and add httpx to requirements

app.py

@@ -23,6 +23,8 @@ from fastapi.responses import StreamingResponse
 import matplotlib
 matplotlib.use('Agg')  # ✅ Force headless-safe backend
 import matplotlib.pyplot as plt  # ✅ Safe to use now
+import httpx
+import io
 import requests
 import datetime
 from io import BytesIO
@@ -90,43 +92,39 @@ def analyze_ner(req: TextRequest):
         logger.error(f"NER analysis error: {e}")
         raise HTTPException(status_code=500, detail="NER analysis failed")
 
+    
+
 @app.post("/chart")
 def generate_chart(req: CoinRequest):
     coin_id = req.coin_id.strip().lower()
-    if not coin_id:
-        raise HTTPException(status_code=400, detail="coin_id cannot be empty")
-
-    url = f"https://api.coingecko.com/api/v3/coins/{coin_id}/market_chart"
-    params = {"vs_currency": "usd", "days": "1"}
+    logger.info(f"Generating chart for coin: {coin_id}")
 
     try:
-        res = requests.get(url, params=params)
-        if res.status_code != 200:
-            logger.error(f"CoinGecko API error: {res.text}")
-            raise HTTPException(status_code=502, detail="Failed to fetch coin data from CoinGecko")
+        url = f"https://api.coingecko.com/api/v3/coins/{coin_id}/market_chart"
+        params = {"vs_currency": "usd", "days": "7"}
+        response = httpx.get(url, params=params)
 
-        prices = res.json().get("prices", [])
-        if not prices:
-            raise HTTPException(status_code=404, detail="No price data available")
+        if response.status_code != 200:
+            logger.error(f"CoinGecko API error: {response.text}")
+            raise HTTPException(status_code=502, detail="Failed to fetch coin data from CoinGecko")
 
-        times = [datetime.datetime.fromtimestamp(p[0] / 1000) for p in prices]
-        values = [p[1] for p in prices]
+        prices = response.json()["prices"]
+        timestamps, values = zip(*prices)
 
-        plt.figure(figsize=(12, 6))
-        plt.fill_between(times, values, color="#1f77b4", alpha=0.3)
-        plt.plot(times, values, color="#1f77b4", linewidth=3)
-        plt.title(f"{coin_id.capitalize()} Price (24h)", fontsize=20)
+        plt.figure(figsize=(6, 3))
+        plt.plot(values, color="blue")
+        plt.title(f"{coin_id.capitalize()} - Last 7 Days")
         plt.xlabel("Time")
-        plt.ylabel("USD Price")
-        plt.grid(True, linestyle='--', alpha=0.5)
-        plt.tight_layout()
+        plt.ylabel("Price (USD)")
+        plt.grid(True)
 
-        img_bytes = BytesIO()
-        plt.savefig(img_bytes, format="png")
+        buffer = io.BytesIO()
+        plt.savefig(buffer, format="png")
         plt.close()
-        img_bytes.seek(0)
+        buffer.seek(0)
+
+        return StreamingResponse(buffer, media_type="image/png")
 
-        return StreamingResponse(img_bytes, media_type="image/png")
     except Exception as e:
-        logger.error(f"Chart generation error: {e}")
-        raise HTTPException(status_code=500, detail="Failed to generate chart")
+        logger.exception(f"Chart generation error: {e}")
+        raise HTTPException(status_code=500, detail="Chart generation failed")