Update app.py

app.py

@@ -2,14 +2,8 @@ import streamlit as st
 import os
 import subprocess
 from streamlit_pdf_viewer import pdf_viewer
-import shutil
+from github import Github
 
-# Add this right after your imports
-if not shutil.which("pdflatex"):
-    st.error("❌ LaTeX compiler not found!")
-    st.info("If you are on HuggingFace/Streamlit Cloud, make sure 'packages.txt' is in the root directory and contains 'texlive-latex-base'.")
-    st.stop()
-    
 # --- Configuration ---
 TOPICS_DIR = "topics"
 TEMP_DIR = "temp_build"
@@ -18,88 +12,102 @@ os.makedirs(TEMP_DIR, exist_ok=True)
 st.set_page_config(page_title="Physics Topics", layout="wide")
 
 # ==========================================
-# 🔒 AUTHENTICATION LOGIC
+# 🔒 AUTHENTICATION LOGIC (DUAL LEVEL)
 # ==========================================
 def check_login():
     """
-    Verifies the password against st.secrets.
-    Returns True if logged in, False otherwise.
+    Returns: 'admin', 'viewer', or None
     """
-    # 1. Initialize session state for authentication
-    if "authenticated" not in st.session_state:
-        st.session_state.authenticated = False
+    if "user_role" not in st.session_state:
+        st.session_state.user_role = None
 
-    # 2. If already logged in, return True immediately
-    if st.session_state.authenticated:
-        return True
+    if st.session_state.user_role:
+        return st.session_state.user_role
 
-    # 3. If not logged in, show the login form
-    st.title("🔒 Login Required")
+    st.title("🔒 Access Restricted")
     
-    # We use a form so the user can hit 'Enter' to submit
     with st.form("login_form"):
-        password_input = st.text_input("Enter Password", type="password")
+        password_input = st.text_input("Enter Access Password", type="password")
         submit_button = st.form_submit_button("Login")
 
         if submit_button:
-            # DIRECT COMPARISON (No Hash as requested)
-            if password_input == st.secrets["app_password"]:
-                st.session_state.authenticated = True
-                st.rerun()  # Rerun the app to remove the login form
+            if password_input == st.secrets["admin_password"]:
+                st.session_state.user_role = "admin"
+                st.success("Logged in as Administrator")
+                st.rerun()
+            elif password_input == st.secrets["viewer_password"]:
+                st.session_state.user_role = "viewer"
+                st.success("Logged in as Viewer")
+                st.rerun()
             else:
-                st.error("❌ Incorrect Password")
+                st.error("❌ Invalid Password")
 
-    return False
+    return None
 
-# STOP THE APP HERE IF NOT LOGGED IN
-if not check_login():
-    st.stop()  # This prevents the rest of the code from running
+# STOP IF NOT LOGGED IN
+current_role = check_login()
+if not current_role:
+    st.stop()
 
 # ==========================================
-# 🚀 MAIN APPLICATION
-# (Only runs if authenticated)
+# 🐙 GITHUB SYNC FUNCTIONS
+# ==========================================
+def push_to_github(local_path, content, commit_message):
+    """
+    Updates the file on GitHub.
+    local_path: 'topics/Topic1/file.tex'
+    """
+    try:
+        g = Github(st.secrets["github_token"])
+        repo = g.get_repo(st.secrets["github_repo"])
+        
+        # Get the file from the repo to retrieve its SHA (needed for update)
+        contents = repo.get_contents(local_path, ref=st.secrets["github_branch"])
+        
+        # Update the file
+        repo.update_file(
+            path=contents.path,
+            message=commit_message,
+            content=content,
+            sha=contents.sha,
+            branch=st.secrets["github_branch"]
+        )
+        return True, "Successfully pushed to GitHub!"
+    except Exception as e:
+        return False, f"GitHub Error: {str(e)}"
+
+# ==========================================
+# 🚀 MAIN APP LOGIC
 # ==========================================
 
-# --- Helper Functions ---
 def get_topics():
     if not os.path.exists(TOPICS_DIR): return []
     return sorted([d for d in os.listdir(TOPICS_DIR) if os.path.isdir(os.path.join(TOPICS_DIR, d))])
 
-def get_tex_files(topic):
+def get_topic_files(topic):
     topic_path = os.path.join(TOPICS_DIR, topic)
-    return sorted([f for f in os.listdir(topic_path) if f.endswith(".tex")])
+    return sorted([f for f in os.listdir(topic_path) if f.lower().endswith(('.tex', '.pdf'))])
 
 def compile_latex(file_path):
     file_name = os.path.basename(file_path)
     job_name = os.path.splitext(file_name)[0]
-    
     try:
         process = subprocess.run(
-            [
-                "pdflatex", 
-                "-interaction=nonstopmode", 
-                f"-output-directory={TEMP_DIR}",
-                f"-jobname={job_name}",
-                file_path
-            ],
-            stdout=subprocess.PIPE,
-            stderr=subprocess.PIPE,
-            text=True
+            ["pdflatex", "-interaction=nonstopmode", f"-output-directory={TEMP_DIR}", f"-jobname={job_name}", file_path],
+            stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True
         )
         pdf_path = os.path.join(TEMP_DIR, f"{job_name}.pdf")
         if process.returncode == 0 and os.path.exists(pdf_path):
             return pdf_path, None
-        else:
-            return None, process.stdout
+        return None, process.stdout
     except Exception as e:
         return None, str(e)
 
-# --- Sidebar Navigation ---
-st.sidebar.title("Physics Archive")
+# --- SIDEBAR ---
+st.sidebar.title(f"Physics Archive ({current_role.title()})")
 
-# Logout Button (Optional but useful)
 if st.sidebar.button("Logout", type="secondary"):
-    st.session_state.authenticated = False
+    st.session_state.user_role = None
     st.rerun()
 
 topics = get_topics()
@@ -107,67 +115,114 @@ if not topics:
     st.sidebar.error("No topics found.")
     st.stop()
 
-# 1. Topic Selection
 selected_topic = st.sidebar.selectbox("Select Topic", topics)
 st.sidebar.markdown("---") 
+files = get_topic_files(selected_topic)
 
-# 2. Document Selection
-tex_files = get_tex_files(selected_topic)
-if not tex_files:
-    st.sidebar.warning("No files in this topic.")
+if not files:
+    st.sidebar.warning("No files found.")
     st.stop()
 
-selected_file = st.sidebar.radio(f"Documents in {selected_topic}", tex_files)
+selected_file = st.sidebar.radio(f"Documents in {selected_topic}", files)
 
+# --- FILE PATHS ---
+# Relative path (for GitHub): "topics/Topic1/File.tex"
+rel_path = os.path.join(TOPICS_DIR, selected_topic, selected_file).replace("\\", "/")
+# Absolute path (for Python/OS):
+abs_path = os.path.abspath(rel_path)
 
-# --- Auto-Compilation & Logic ---
-source_path = os.path.join(TOPICS_DIR, selected_topic, selected_file)
+# --- COMPILATION LOGIC (VIEWER & ADMIN) ---
+# We track if a file was just saved to trigger a re-compile
+if "force_recompile" not in st.session_state:
+    st.session_state.force_recompile = False
 
-if "last_compiled_file" not in st.session_state:
-    st.session_state.last_compiled_file = None
-if "compilation_error" not in st.session_state:
-    st.session_state.compilation_error = None
+if "last_processed" not in st.session_state:
+    st.session_state.last_processed = None
 
-if st.session_state.last_compiled_file != source_path:
-    with st.spinner(f"Rendering {selected_file}..."):
-        pdf_path, error_log = compile_latex(source_path)
+# If file changed OR we just saved an edit:
+if st.session_state.last_processed != rel_path or st.session_state.force_recompile:
+    
+    # 1. PDF Files
+    if selected_file.lower().endswith(".pdf"):
+        st.session_state.current_pdf = abs_path
+        st.session_state.compilation_error = None
         
-        if pdf_path:
-            st.session_state.current_pdf_path = pdf_path
-            st.session_state.last_compiled_file = source_path
-            st.session_state.compilation_error = None
-        else:
-            st.session_state.current_pdf_path = None
-            st.session_state.compilation_error = error_log
-
-# --- Main View ---
-tab_view, tab_code = st.tabs(["📄 Document Viewer", "📝 Source Code"])
-
+    # 2. LaTeX Files
+    elif selected_file.lower().endswith(".tex"):
+        with st.spinner(f"Compiling {selected_file}..."):
+            pdf, log = compile_latex(abs_path)
+            st.session_state.current_pdf = pdf
+            st.session_state.compilation_error = log
+            
+    st.session_state.last_processed = rel_path
+    st.session_state.force_recompile = False
+
+# --- TABS ---
+# Admin gets "Edit Source", Viewer gets "Source Code"
+tab_label = "✏️ Edit Source" if current_role == 'admin' else "📝 Source Code"
+tab_view, tab_edit = st.tabs(["📄 Document Viewer", tab_label])
+
+# 1. VIEWER TAB
 with tab_view:
-    if st.session_state.get("current_pdf_path") and os.path.exists(st.session_state.current_pdf_path):
-        
+    if st.session_state.current_pdf and os.path.exists(st.session_state.current_pdf):
         col1, col2 = st.columns([6, 1])
-        with col1:
-            st.success(f"**{selected_file}** rendered successfully.")
+        with col1: st.success(f"**{selected_file}** loaded.")
         with col2:
-            with open(st.session_state.current_pdf_path, "rb") as f:
-                st.download_button(
-                    label="⬇️ Download PDF",
-                    data=f,
-                    file_name=selected_file.replace('.tex', '.pdf'),
-                    mime="application/pdf",
-                    type="primary"
-                )
+            with open(st.session_state.current_pdf, "rb") as f:
+                st.download_button("⬇️ PDF", f, file_name=selected_file.replace('.tex','.pdf'), mime="application/pdf", type="primary")
         
         st.markdown("---")
-        pdf_viewer(st.session_state.current_pdf_path, width=800, height=1000)
-
-    elif st.session_state.get("compilation_error"):
+        pdf_viewer(st.session_state.current_pdf, width=800, height=1000)
+    elif st.session_state.compilation_error:
         st.error("⚠️ Compilation Failed")
-        with st.expander("View Error Log", expanded=True):
-            st.code(st.session_state.compilation_error, language="text")
-
-with tab_code:
-    st.caption(f"File: {source_path}")
-    with open(source_path, "r", encoding="utf-8") as f:
-        st.code(f.read(), language="latex")
+        with st.expander("Error Log"):
+            st.code(st.session_state.compilation_error)
+
+# 2. EDIT / SOURCE TAB
+with tab_edit:
+    if selected_file.lower().endswith(".pdf"):
+        st.info("PDF files cannot be edited directly.")
+    else:
+        # Read current content
+        with open(abs_path, "r", encoding="utf-8") as f:
+            file_content = f.read()
+
+        if current_role == 'admin':
+            st.warning(f"⚠️ You are editing: {selected_file}")
+            
+            # The Text Editor
+            new_content = st.text_area(
+                "LaTeX Source", 
+                value=file_content, 
+                height=600,
+                key="editor_area"
+            )
+
+            # SAVE BUTTON
+            if st.button("💾 Save to GitHub & Re-Render", type="primary"):
+                if new_content != file_content:
+                    # 1. Save locally (so valid for compilation immediately)
+                    with open(abs_path, "w", encoding="utf-8") as f:
+                        f.write(new_content)
+                    
+                    # 2. Push to GitHub
+                    with st.spinner("Pushing to GitHub..."):
+                        success, msg = push_to_github(
+                            rel_path, 
+                            new_content, 
+                            f"Update {selected_file} via Streamlit Admin"
+                        )
+                    
+                    if success:
+                        st.success(msg)
+                        # Trigger re-compile on next run
+                        st.session_state.force_recompile = True
+                        st.rerun()
+                    else:
+                        st.error(msg)
+                else:
+                    st.info("No changes detected.")
+        else:
+            # Viewer Mode (Read Only)
+            st.caption(f"Path: {rel_path}")
+            st.code(file_content, language="latex")