added font path for HF Spaces

Dockerfile

@@ -4,11 +4,13 @@ FROM python:3.11-slim
 WORKDIR /app
 
 # Install system dependencies
+# fonts-noto-extra provides NotoSansDevanagari as fallback if Kalimati download fails
 RUN apt-get update && apt-get install -y \
     build-essential \
     curl \
     git \
     fontconfig \
+    fonts-noto-extra \
     && rm -rf /var/lib/apt/lists/*
 
 # Copy requirements first for better Docker layer caching
@@ -27,9 +29,9 @@ RUN mkdir -p /app/fonts && \
     -o /app/fonts/Kalimati.ttf || \
     curl -L "https://github.com/virtual-labs/virtual-labs.github.io/raw/master/fonts/Kalimati.ttf" \
     -o /app/fonts/Kalimati.ttf || \
-    echo "WARNING: Kalimati font download failed, Devanagari may not render correctly"
+    echo "WARNING: Kalimati font download failed, falling back to Noto Sans Devanagari"
 
-# Register font with system font cache
+# Register Kalimati font with system font cache
 RUN if [ -f /app/fonts/Kalimati.ttf ]; then \
         mkdir -p /usr/local/share/fonts/nepali && \
         cp /app/fonts/Kalimati.ttf /usr/local/share/fonts/nepali/ && \
@@ -37,7 +39,6 @@ RUN if [ -f /app/fonts/Kalimati.ttf ]; then \
     fi
 
 # Set environment variables
-# PYTHONPATH includes both /app (for scripts/) and /app/src (for streamlit_app.py imports)
 ENV PYTHONPATH=/app:/app/src
 ENV HF_HOME=/tmp/huggingface
 ENV TRANSFORMERS_CACHE=/tmp/huggingface

src/streamlit_app.py

@@ -159,19 +159,44 @@ st.markdown("""
 
 @st.cache_resource
 def load_nepali_font():
-    """Load Nepali font for matplotlib visualizations."""
+    """Load Nepali font for matplotlib visualizations.
+    
+    Tries multiple font paths in order of preference:
+    1. Kalimati (primary — downloaded by Dockerfile)
+    2. Noto Sans Devanagari (Linux/HF Spaces fallback)
+    3. Other system Devanagari fonts (macOS, Windows)
+    """
     font_paths = [
-        # HF Spaces / Docker — Kalimati downloaded by Dockerfile into /app/fonts/
+        # ── Kalimati (primary) ──────────────────────────────────────────
+        # HF Spaces / Docker — downloaded by Dockerfile curl command
         '/app/fonts/Kalimati.ttf',
-        # Kalimati registered system-wide by fc-cache in Dockerfile
+        # Registered system-wide by fc-cache in Dockerfile
         '/usr/local/share/fonts/nepali/Kalimati.ttf',
-        # Local development (absolute path relative to script)
+        # Local dev — absolute path relative to script location
         os.path.join(BASE_DIR, 'fonts', 'Kalimati.ttf'),
+        # Local dev — relative path
         'fonts/Kalimati.ttf',
-        # macOS
+
+        # ── Noto Sans Devanagari (Linux / HF Spaces fallback) ───────────
+        '/usr/share/fonts/truetype/noto/NotoSansDevanagari-Regular.ttf',
+        '/usr/share/fonts/truetype/noto/NotoSansDevanagari[wdth,wght].ttf',
+        '/usr/share/fonts/opentype/noto/NotoSansDevanagari-Regular.otf',
+        '/usr/share/fonts/noto/NotoSansDevanagari-Regular.ttf',
+        # Noto Serif Devanagari variant
+        '/usr/share/fonts/truetype/noto/NotoSerifDevanagari-Regular.ttf',
+        # Generic Noto fallback
+        '/usr/share/fonts/truetype/noto/NotoSans-Regular.ttf',
+
+        # ── macOS ────────────────────────────────────────────────────────
         '/System/Library/Fonts/Supplemental/DevanagariSangamMN.ttc',
-        # Windows
-        'C:\\Windows\\Fonts\\NirmalaUI.ttf',
+        '/System/Library/Fonts/Supplemental/DevanagariMT.ttc',
+        '/Library/Fonts/Devanagari Sangam MN.ttc',
+
+        # ── Windows ─────────────────────────────────────────────────────
+        'C:\Windows\Fonts\NirmalaUI.ttf',
+        'C:\Windows\Fonts\NirmalaUI-Bold.ttf',
+        'C:\Windows\Fonts\mangal.ttf',
+        'C:\Windows\Fonts\Aparajita.ttf',
     ]
 
     for font_path in font_paths: