Add document segmentation feedback to UI (#23)

* Add document segmentation feedback to UI

* style: fix formatting and trailing whitespace

Author: alexmeckes

demo/app.py

@@ -19,7 +19,7 @@ def load_model():
 
 @st.cache_resource
 def convert_to_sections(uploaded_file, output_dir):
-    document_to_sections_dir(
+    return document_to_sections_dir(
         pymupdf.open("type", BytesIO(uploaded_file.read())),
         output_dir,
     )
@@ -39,23 +39,55 @@ def convert_to_sections(uploaded_file, output_dir):
     st.markdown("[Docs for this Step]()")
     st.divider()
 
-    convert_to_sections(uploaded_file, f"example_outputs/{uploaded_file.name}")
-
-    sections = [f.stem for f in Path(f"example_outputs/{uploaded_file.name}").iterdir()]
-    st.json(sections)
-
-    model = load_model()
-    question = st.text_input("Enter a question:")
-    if question:
-        with st.spinner("Answering..."):
-            answer, sections_checked = find_retrieve_answer(
-                model=model,
-                sections_dir=f"example_outputs/{uploaded_file.name}",
-                question=question,
-                find_prompt=FIND_PROMPT,
-                answer_prompt=ANSWER_PROMPT,
+    try:
+        with st.spinner("Converting document to sections..."):
+            section_names = convert_to_sections(
+                uploaded_file, f"example_outputs/{uploaded_file.name}"
             )
-            st.text("Sections checked:")
-            st.json(sections_checked)
-            st.text("Answer:")
-            st.text(answer)
+            sections = [
+                f.stem for f in Path(f"example_outputs/{uploaded_file.name}").iterdir()
+            ]
+
+            # Provide feedback about segmentation
+            st.success(
+                f"Successfully extracted {len(sections)} sections from the document."
+            )
+
+            # Check for potential segmentation issues
+            if len(sections) == 1:
+                st.warning(
+                    "⚠️ Only one section was found. This might indicate that the document structure wasn't properly detected."
+                )
+            elif len(sections) == 0:
+                st.error(
+                    "❌ No sections were found in the document. The document might not have a clear structure or might be in an unsupported format."
+                )
+            elif "INTRO" in sections and len(sections) < 3:
+                st.warning(
+                    "⚠️ Only found default sections. The document structure might not have been properly detected."
+                )
+
+            # Show sections
+            st.text("Detected Sections:")
+            st.json(sections)
+
+            model = load_model()
+            question = st.text_input("Enter a question:")
+            if question:
+                with st.spinner("Answering..."):
+                    answer, sections_checked = find_retrieve_answer(
+                        model=model,
+                        sections_dir=f"example_outputs/{uploaded_file.name}",
+                        question=question,
+                        find_prompt=FIND_PROMPT,
+                        answer_prompt=ANSWER_PROMPT,
+                    )
+                    st.text("Sections checked:")
+                    st.json(sections_checked)
+                    st.text("Answer:")
+                    st.text(answer)
+    except Exception as e:
+        st.error(f"❌ Error processing document: {str(e)}")
+        st.info(
+            "💡 Try uploading a different document or check if the file is corrupted."
+        )