Update app.py

app.py

@@ -16,7 +16,13 @@ from linebot.v3.webhooks import MessageEvent, TextMessageContent
 
 import requests
 import pandas as pd
-import plotly.express as px
+
+# --- Matplotlib (no GUI) ---
+import matplotlib
+matplotlib.use("Agg")   # headless backend
+import matplotlib.pyplot as plt
+from matplotlib.colors import Normalize
+import matplotlib.cm as cm
 
 # --- Environment Variables ---
 CHANNEL_ACCESS_TOKEN = os.getenv("CHANNEL_ACCESS_TOKEN")
@@ -139,41 +145,61 @@ def fetch_taiwan_df_this_year(min_mag=5.0) -> pd.DataFrame | str:
     except Exception as e:
         return f"❌ 查詢失敗: {e}"
 
-# --- Map (PNG via kaleido) ---
+# --- Map (PNG via Matplotlib, no Chrome needed) ---
 def create_and_save_map(df: pd.DataFrame) -> str:
-    fig = px.scatter_geo(
-        df,
-        lat="latitude",
-        lon="longitude",
-        size="magnitude",
-        color="magnitude",
-        hover_name="place",
-        hover_data={"magnitude": ":.1f", "time_utc": "|%Y-%m-%d %H:%M UTC"},
-        size_max=24,
-        color_continuous_scale=px.colors.sequential.YlOrRd,
-        projection="natural earth",
-    )
-    fig.update_layout(
-        title=f"<b>今年 ({datetime.now(timezone.utc).year}) 台灣區域顯著地震 (M≥5.0)</b>",
-        margin=dict(r=0, t=40, l=0, b=0),
-    )
-    fig.update_geos(
-        lonaxis_range=[118.5, 123.5],
-        lataxis_range=[20.5, 26.8],
-        showcountries=True,
-        showland=True,
-        landcolor="#f8f8f8",
-        countrycolor="#aaa",
+    # Figure
+    fig, ax = plt.subplots(figsize=(9, 6), dpi=150)
+
+    # Taiwan bounding box & grid
+    lon_min, lon_max = 118.5, 123.5
+    lat_min, lat_max = 20.5, 26.8
+    ax.set_xlim(lon_min, lon_max)
+    ax.set_ylim(lat_min, lat_max)
+    ax.set_xlabel("Longitude (°E)")
+    ax.set_ylabel("Latitude (°N)")
+    ax.set_title(f"今年 ({datetime.now(timezone.utc).year}) 台灣區域顯著地震 (M≥5.0)  — UTC")
+
+    ax.grid(True, linestyle="--", linewidth=0.5, alpha=0.4)
+
+    # Scatter colored by magnitude
+    mags = df["magnitude"].astype(float).clip(lower=0)
+    norm = Normalize(vmin=max(4.5, mags.min()), vmax=max(6.5, mags.max()))
+    cmap = cm.get_cmap("YlOrRd")
+    colors = cmap(norm(mags.values))
+
+    # Size scale (points^2): tune for LINE preview
+    sizes = 15 + (mags - mags.min()) * 25  # 15–approx 140
+
+    sc = ax.scatter(
+        df["longitude"].values,
+        df["latitude"].values,
+        s=sizes,
+        c=colors,
+        edgecolor="k",
+        linewidths=0.4,
+        alpha=0.9,
     )
+
+    # Colorbar
+    cbar = fig.colorbar(cm.ScalarMappable(norm=norm, cmap=cmap), ax=ax, pad=0.02)
+    cbar.set_label("Magnitude")
+
+    # Legend example (size ~ mag)
+    for m in [5.0, 6.0, 7.0]:
+        ax.scatter([], [], s=15 + (m - mags.min()) * 25, c="none", edgecolor="k", label=f"M {m:.1f}")
+    ax.legend(title="Size ∝ Magnitude", loc="lower right", framealpha=0.9)
+
+    # Save
     filename = f"map_{uuid.uuid4().hex}.png"
     filepath = os.path.join(STATIC_DIR, filename)
-    fig.write_image(filepath, scale=2, width=900, height=600)  # needs kaleido
+    fig.tight_layout()
+    fig.savefig(filepath)
+    plt.close(fig)
     return filename
 
 def _base_url_for_images() -> str:
     if HF_SPACE_URL:
         return HF_SPACE_URL.rstrip("/")
-    # request.url_root includes trailing slash; safe if running behind proxy
     return request.url_root.rstrip("/")
 
 # --- LINE Webhook ---