Update app.py

app.py

@@ -1,169 +1,263 @@
 # -*- coding: utf-8 -*-
 """
-app.py – RadVision AI Advanced (main entry‑point)
-================================================
-Lightweight orchestrator that wires together:
+app.py – RadVision AI Advanced (main entry‑point)
+-------------------------------------------------
+Split‑architecture version that wires together:
+    • sidebar_ui.py          – upload & action buttons
+    • main_page_ui.py        – viewer + tabbed results
+    • file_processing.py     – image / DICOM ingestion
+    • action_handlers.py     – runs AI, UMLS, report
 
-• sidebar_ui.py    – upload panel & action buttons  
-• main_page_ui.py  – viewer + tabbed results (AI / UMLS / Translate …)  
-• file_processing.py – DICOM / image ingestion + ROI plumbing  
-• action_handlers.py – runs Gemini, UMLS enrichment, PDF reporting  
-
-Heavy logic lives in the helper modules; this file focuses on flow control.
+This file primarily orchestrates the application flow and displays
+high‑level status banners (e.g., missing optional dependencies).
+Heavy logic resides within the imported helper modules.
 """
 from __future__ import annotations
 
-# ──────────────────────────────────────────────────────────────────────────────
-# Standard library
-# ──────────────────────────────────────────────────────────────────────────────
+# Standard library imports should come first
 import logging
 import sys
 import io
 import base64
-from typing import Any
+import os
+from typing import Any, TYPE_CHECKING
 
-# ──────────────────────────────────────────────────────────────────────────────
-# 3rd‑party
-# ──────────────────────────────────────────────────────────────────────────────
+# Third-party imports
 import streamlit as st
+from streamlit.runtime.scriptrunner import get_script_run_ctx # For reliable session ID
 
-# Pillow is required for the image‑to‑data‑URL monkey‑patch (for st_canvas).
+# Pillow is checked for availability, crucial for the monkey-patch.
 try:
-    from PIL import Image  # noqa: WPS433 – external import
+    from PIL import Image
     PIL_AVAILABLE = True
-except ImportError:  # pragma: no cover – Space will show UI error banner
+except ImportError:
     PIL_AVAILABLE = False
-    Image = None  # type: ignore
+    Image = None # type: ignore[assignment, misc] # Define Image as None if Pillow isn't installed
+
+# Conditional import for type checking improves static analysis
+if TYPE_CHECKING:
+    from streamlit.runtime.uploaded_file_manager import UploadedFile
 
-# ──────────────────────────────────────────────────────────────────────────────
-# Internal modules (each kept small & focused)
-# ──────────────────────────────────────────────────────────────────────────────
-from config import LOG_LEVEL, LOG_FORMAT, DATE_FORMAT, APP_CSS, FOOTER_MARKDOWN
+# Local application/library specific imports
+# Configuration should be imported early
+from config import (
+    LOG_LEVEL,
+    LOG_FORMAT,
+    DATE_FORMAT,
+    APP_CSS,
+    FOOTER_MARKDOWN,
+    APP_TITLE,
+    APP_ICON,
+    USER_GUIDE_MARKDOWN, # Assuming user guide text is moved to config
+    DISCLAIMER_WARNING, # Assuming disclaimer is moved to config
+)
+# Core application modules
 from session_state import initialize_session_state
 from sidebar_ui import render_sidebar
 from main_page_ui import render_main_content
 from file_processing import handle_file_upload
 from action_handlers import handle_action
 
-# -----------------------------------------------------------------------------
-# Streamlit page config – **must** be first Streamlit call
-# -----------------------------------------------------------------------------
+# Optional helpers (check availability without crashing)
+try:
+    # Assuming translation_models exports this constant
+    from translation_models import TRANSLATION_AVAILABLE
+except ImportError:
+    TRANSLATION_AVAILABLE = False
+
+try:
+    # Assuming umls_utils exports this constant
+    from umls_utils import UMLS_AVAILABLE, UMLS_CONFIG_MSG # Add message for clarity
+except ImportError:
+    UMLS_AVAILABLE = False
+    # Provide a default message if the module itself is missing
+    UMLS_CONFIG_MSG = "Add `UMLS_APIKEY` to HF Secrets & restart."
+
+
+# ---------------------------------------------------------------------------
+# Helper Functions
+# ---------------------------------------------------------------------------
+def get_session_id() -> str:
+    """Retrieves the current Streamlit session ID reliably."""
+    ctx = get_script_run_ctx()
+    return ctx.session_id if ctx else "N/A"
+
+# ---------------------------------------------------------------------------
+# Streamlit Page Configuration (Must be the *first* Streamlit command)
+# ---------------------------------------------------------------------------
 st.set_page_config(
-    page_title="RadVision AI Advanced",
-    page_icon="⚕️",
+    page_title=APP_TITLE,
+    page_icon=APP_ICON,
     layout="wide",
     initial_sidebar_state="expanded",
 )
 
-# -----------------------------------------------------------------------------
-# Logging
-# -----------------------------------------------------------------------------
-for h in logging.root.handlers[:]:
-    logging.root.removeHandler(h)
+# ---------------------------------------------------------------------------
+# Logging Configuration (Clear existing handlers, set new format)
+# ---------------------------------------------------------------------------
+# Remove default Streamlit handlers to prevent duplicate logs
+for handler in logging.root.handlers[:]:
+    logging.root.removeHandler(handler)
 
+# Configure root logger
 logging.basicConfig(
     level=LOG_LEVEL,
     format=LOG_FORMAT,
     datefmt=DATE_FORMAT,
-    stream=sys.stdout,
+    stream=sys.stdout, # Log to stdout for containerized environments
+    force=True # Override any existing configuration
 )
 logger = logging.getLogger(__name__)
-logger.info("↪︎  RadVision AI bootstrap (Streamlit v%s)", st.__version__)
+logger.info("--- RadVision AI App Initializing (Streamlit v%s) ---", st.__version__)
 
-# -----------------------------------------------------------------------------
-# Session‑state defaults
-# -----------------------------------------------------------------------------
-initialize_session_state()
+# ---------------------------------------------------------------------------
+# Session State Initialization (Ensure it runs early)
+# ---------------------------------------------------------------------------
+initialize_session_state(get_session_id()) # Pass session ID during init if needed
+logger.debug("Session state initialized.")
 
-# -----------------------------------------------------------------------------
-# Inject custom global CSS
-# -----------------------------------------------------------------------------
+# ---------------------------------------------------------------------------
+# Apply Global CSS Styles
+# ---------------------------------------------------------------------------
 st.markdown(APP_CSS, unsafe_allow_html=True)
+logger.debug("Global CSS applied.")
+
+# ---------------------------------------------------------------------------
+# Monkey-Patch for st.image (if needed and Pillow is available)
+# Required for st_canvas snapshot rendering compatibility
+# ---------------------------------------------------------------------------
+import streamlit.elements.image as st_image # Use alias for clarity
+
+# Check if the function *already exists* (e.g., future Streamlit versions)
+if not hasattr(st_image, "image_to_url"):
+    if not PIL_AVAILABLE:
+        logger.warning("Pillow library not found. Cannot apply image_to_url monkey-patch.")
+    else:
+        logger.info("Applying monkey-patch for st.image -> data-url generation.")
+        def _image_to_url_monkey_patch(
+            image: Any, # Can be various types, PIL Image is key
+            width: int = -1,
+            clamp: bool = False,
+            channels: str = "RGB",
+            output_format: str = "auto",
+            image_id: str = "", # May be used by Streamlit internally
+        ) -> str:
+            """
+            Serializes PIL Image to a base64 data URL.
+            Needed for components like streamlit-drawable-canvas to redisplay images.
+            Handles basic format conversions (e.g., palette to RGBA, alpha channel).
+            """
+            # Ensure input is a PIL Image object
+            if not isinstance(image, Image.Image):
+                logger.warning("image_to_url: Input is not a PIL Image (%s). Returning empty URL.", type(image))
+                return ""
+
+            # Determine output format, defaulting to PNG
+            fmt = output_format.upper() if output_format != "auto" else (image.format or "PNG")
+            if fmt not in {"PNG", "JPEG", "WEBP", "GIF"}:
+                logger.debug("image_to_url: Unsupported format '%s', falling back to PNG.", fmt)
+                fmt = "PNG"
+
+            # Handle alpha channel compatibility (JPEG doesn't support alpha)
+            if image.mode == "RGBA" and fmt == "JPEG":
+                logger.debug("image_to_url: RGBA image requested as JPEG, converting to PNG.")
+                fmt = "PNG" # Switch to PNG to preserve alpha
+
+            # Convert palette images (mode 'P') to RGBA for broader compatibility
+            if image.mode == "P":
+                logger.debug("image_to_url: Converting Palette image (mode 'P') to RGBA.")
+                image = image.convert("RGBA")
+
+            # Convert to RGB if requested and necessary
+            if channels == "RGB" and image.mode not in {"RGB", "L"}: # 'L' (grayscale) is fine
+                logger.debug("image_to_url: Converting image mode '%s' to RGB.", image.mode)
+                image = image.convert("RGB")
 
-# -----------------------------------------------------------------------------
-# Monkey‑patch: st.elements.image.image_to_url  ⇢  data‑URL encoder
-# Needed for streamlit‑drawable‑canvas screenshots
-# -----------------------------------------------------------------------------
-import streamlit.elements.image as _st_image  # noqa: WPS433
-
-if not hasattr(_st_image, "image_to_url"):
-
-    def _image_to_url_monkey_patch(       # noqa: C901 – kept simple & explicit
-        img_obj: Any,
-        width: int = -1,
-        clamp: bool = False,
-        channels: str = "RGB",
-        output_format: str = "auto",
-        image_id: str = "",
-    ) -> str:
-        """Return a **data:URL** for a PIL Image so st_canvas can re‑render."""
-        if not (PIL_AVAILABLE and isinstance(img_obj, Image.Image)):
-            logger.warning("[patch] image_to_url: unsupported type %s", type(img_obj))
-            return ""
-
-        # ---------- normalise format ----------
-        fmt = (output_format.upper() if output_format != "auto" else (img_obj.format or "PNG"))
-        if fmt not in {"PNG", "JPEG", "WEBP", "GIF"}:
-            fmt = "PNG"
-        if img_obj.mode == "RGBA" and fmt == "JPEG":  # JPEG has no alpha
-            fmt = "PNG"
-
-        # ---------- convert if needed ----------
-        if img_obj.mode == "P":             # palette → RGBA
-            img_obj = img_obj.convert("RGBA")
-        if channels == "RGB" and img_obj.mode not in {"RGB", "L"}:
-            img_obj = img_obj.convert("RGB")
-
-        # ---------- encode ----------
-        buf = io.BytesIO()
-        img_obj.save(buf, format=fmt)
-        b64 = base64.b64encode(buf.getvalue()).decode("ascii")
-        return f"data:image/{fmt.lower()};base64,{b64}"
-
-    _st_image.image_to_url = _image_to_url_monkey_patch  # type: ignore[attr-defined]
-    logger.info("✔︎  Patched st.image → data‑URL encoder")
-
-# ──────────────────────────────────────────────────────────────────────────────
-# UI flow
-# ──────────────────────────────────────────────────────────────────────────────
-# 1️⃣  Sidebar (upload, actions)  → returns file‑uploader object
-uploaded_file = render_sidebar()
-
-# 2️⃣  Process uploaded file (populate session‑state images / DICOM data)
+            # Save image to an in-memory buffer
+            buffer = io.BytesIO()
+            try:
+                image.save(buffer, format=fmt)
+                img_data = buffer.getvalue()
+            except Exception as e:
+                logger.error("image_to_url: Failed to save image to buffer (format: %s): %s", fmt, e)
+                return ""
+
+            # Encode buffer to base64 and create data URL
+            b64_data = base64.b64encode(img_data).decode("utf-8")
+            return f"data:image/{fmt.lower()};base64,{b64_data}"
+
+        # Apply the patch
+        st_image.image_to_url = _image_to_url_monkey_patch # type: ignore[attr-defined]
+        logger.info("Monkey-patch applied successfully.")
+else:
+    logger.info("Streamlit version >= X.Y.Z already has image_to_url. Skipping monkey-patch.")
+
+
+# ---------------------------------------------------------------------------
+# === Main Application Flow ===
+# ---------------------------------------------------------------------------
+
+# --- 1. Render Sidebar & Get Uploaded File ---
+# The sidebar function handles its own elements and returns the file object
+uploaded_file: UploadedFile | None = render_sidebar()
+logger.debug("Sidebar rendered. Uploaded file: %s", uploaded_file.name if uploaded_file else "None")
+
+# --- 2. Process Uploaded File ---
+# This function updates session state with the processed image data
 handle_file_upload(uploaded_file)
+# Logging within handle_file_upload is assumed
+
+# --- 3. Render Main Content Area ---
+# Title, User Guide Expander, Columns, Viewer, Results Tabs
+st.divider() # Use st.divider() for modern separator
+st.title(f"{APP_ICON} {APP_TITLE} · AI-Assisted Image Analysis")
+
+with st.expander("User Guide & Disclaimer", expanded=False):
+    st.warning(f"⚠️ **Disclaimer**: {DISCLAIMER_WARNING}")
+    st.markdown(USER_GUIDE_MARKDOWN, unsafe_allow_html=True) # Assuming markdown format
 
-# 3️⃣  Main page layout (left: viewer · right: tabbed results)
-st.markdown("---")
-st.title("⚕️ RadVision AI Advanced · AI‑Assisted Image Analysis")
-with st.expander("User Guide & Disclaimer", expanded=False):
-    st.warning(
-        "⚠️ **Disclaimer**: For research / educational use only – "
-        "not intended for primary diagnostic decisions.",
-    )
-    st.markdown(
-        """
-        **Workflow**
-        1. **Upload** image (or enable **Demo Mode**).  
-        2. *(DICOM)* adjust **Window / Level** if needed.  
-        3. *(optional)* draw an **ROI** rectangle on the viewer.  
-        4. Trigger **AI actions** from the sidebar.  
-        5. Explore tabs – **Translate**, **UMLS**, **Confidence** …  
-        6. **Generate PDF** for a portable report.
-        """,
-    )
-st.markdown("---")
-
-col1, col2 = st.columns([2, 3], gap="large")
-render_main_content(col1, col2)
-
-# 4️⃣  Perform deferred action (set via sidebar buttons)
-if (action := st.session_state.get("last_action")):
+st.divider() # Use st.divider()
+
+# Define layout columns
+col_img_viewer, col_analysis_results = st.columns([2, 3], gap="large") # Use descriptive names
+
+# Render the main page UI components into the columns
+render_main_content(col_img_viewer, col_analysis_results)
+logger.debug("Main content area rendered.")
+
+# --- 4. Handle Deferred Actions ---
+# Check if an action button was clicked (state set in sidebar_ui or action_handlers)
+action = st.session_state.get("last_action")
+if action:
+    logger.info("Executing deferred action: '%s'", action)
+    # Action handler manages its own logic, spinners, and state updates
     handle_action(action)
+    # Reset the action trigger ONLY if the handler didn't redirect/rerun
+    if st.session_state.get("last_action") == action: # Check if state changed during handler
+         st.session_state.last_action = None # Prevent re-triggering on next rerun
+         logger.debug("Action '%s' completed and reset.", action)
+else:
+    logger.debug("No deferred action pending.")
+
+
+# --- 5. Display Status Banners for Optional Features ---
+# These appear near the bottom, informed by the availability flags
+if not TRANSLATION_AVAILABLE:
+    st.warning("🌐 Translation backend not loaded – install `deep-translator` & restart.")
+    logger.warning("Optional feature unavailable: Translation (deep-translator not found).")
+
+if not UMLS_AVAILABLE:
+    st.warning(f"🧬 UMLS features unavailable – {UMLS_CONFIG_MSG}")
+    logger.warning("Optional feature unavailable: UMLS (%s)", UMLS_CONFIG_MSG)
+
 
-# -----------------------------------------------------------------------------
-# Footer
-# -----------------------------------------------------------------------------
-st.markdown("---")
-st.caption(f"⚕️ RadVision AI Advanced | Session ID: {st.session_state.get('session_id', 'N/A')}")
+# --- 6. Render Footer ---
+st.divider() # Use st.divider()
+# Use the reliable session ID getter
+current_session_id = get_session_id()
+st.caption(f"{APP_ICON} {APP_TITLE} | Session ID: {current_session_id}")
 st.markdown(FOOTER_MARKDOWN, unsafe_allow_html=True)
-logger.info("✓  Render cycle complete – Session ID %s", st.session_state.get("session_id"))
+logger.info("--- Render cycle complete – Session ID: %s ---", current_session_id)
+# ---------------------------------------------------------------------------
+# === End of Application Flow ===
+# ---------------------------------------------------------------------------