Update app.py

app.py

@@ -20,25 +20,30 @@ except ImportError:
 
 # Set page configuration
 st.set_page_config(
-    page_title="Professional LaTeX Editor",
+    page_title="Professional LaTeX Editor with Chinese Support",
     page_icon="📝",
     layout="wide",
     initial_sidebar_state="collapsed"
 )
 
-# Check if pdflatex is available
-def is_pdflatex_installed():
-    return shutil.which("pdflatex") is not None
+# Check if LaTeX engines are available
+def check_latex_engines():
+    engines = {
+        'pdflatex': shutil.which("pdflatex") is not None,
+        'xelatex': shutil.which("xelatex") is not None,
+        'lualatex': shutil.which("lualatex") is not None
+    }
+    return engines
 
-# Function to convert LaTeX to PDF
-def latex_to_pdf(latex_code):
-    # Check if pdflatex is installed
-    if not is_pdflatex_installed():
-        st.error("pdflatex not found. Debug info:")
+# Function to convert LaTeX to PDF with engine selection
+def latex_to_pdf(latex_code, engine='xelatex'):
+    # Check if the specified engine is installed
+    if not shutil.which(engine):
+        st.error(f"{engine} not found. Debug info:")
         st.code(f"PATH: {os.environ.get('PATH')}")
-        result = subprocess.run(["which", "pdflatex"], capture_output=True, text=True)
-        st.code(f"which pdflatex: {result.stdout} {result.stderr}")
-        return None, "", "Error: pdflatex is not installed or not in PATH."
+        result = subprocess.run(["which", engine], capture_output=True, text=True)
+        st.code(f"which {engine}: {result.stdout} {result.stderr}")
+        return None, "", f"Error: {engine} is not installed or not in PATH."
     
     with tempfile.TemporaryDirectory() as temp_dir:
         temp_path = Path(temp_dir)
@@ -46,16 +51,20 @@ def latex_to_pdf(latex_code):
         pdf_file = temp_path / "document.pdf"
         
         # Write LaTeX code to file
-        with open(tex_file, "w") as f:
+        with open(tex_file, "w", encoding='utf-8') as f:
             f.write(latex_code)
         
         try:
-            # Run pdflatex to compile the LaTeX file
-            process = subprocess.run(
-                ["pdflatex", "-interaction=nonstopmode", "-output-directory", temp_dir, str(tex_file)],
-                capture_output=True,
-                text=True
-            )
+            # Different compilation arguments for different engines
+            if engine == 'xelatex':
+                cmd = ["xelatex", "-interaction=nonstopmode", "-output-directory", temp_dir, str(tex_file)]
+            elif engine == 'lualatex':
+                cmd = ["lualatex", "-interaction=nonstopmode", "-output-directory", temp_dir, str(tex_file)]
+            else:  # pdflatex
+                cmd = ["pdflatex", "-interaction=nonstopmode", "-output-directory", temp_dir, str(tex_file)]
+            
+            # Run LaTeX engine to compile the file
+            process = subprocess.run(cmd, capture_output=True, text=True)
             
             # Check if PDF was created
             if pdf_file.exists():
@@ -198,8 +207,116 @@ def find_environments(latex_code):
     
     return environments
 
-# Default LaTeX template
-default_template = r"""\documentclass{article}
+# Default LaTeX template with Chinese support
+default_template_chinese = r"""\documentclass{article}
+\usepackage{xeCJK}
+\usepackage{amsmath}
+\usepackage{amssymb}
+\usepackage{graphicx}
+\usepackage{hyperref}
+\usepackage{xcolor}
+\usepackage{geometry}
+
+% Set Chinese fonts (using Noto fonts available in the container)
+\setCJKmainfont{Noto Serif CJK SC}
+\setCJKsansfont{Noto Sans CJK SC}
+\setCJKmonofont{Noto Sans Mono CJK SC}
+
+% Page geometry
+\geometry{a4paper, margin=1in}
+
+\title{中文LaTeX文档示例}
+\author{作者姓名}
+\date{\today}
+
+\begin{document}
+
+\maketitle
+
+\section{简介}
+这是一个支持中文的LaTeX文档示例。您可以在这里编写中文内容。
+
+This document also supports English text seamlessly mixed with Chinese characters.
+
+\section{数学表达式}
+\subsection{方程式}
+著名的爱因斯坦质能方程：
+\begin{equation}
+    E = mc^2
+\end{equation}
+
+二次方程求解公式：
+\begin{equation}
+    x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
+\end{equation}
+
+\subsection{微积分}
+积分示例：
+\begin{equation}
+    \int_{0}^{\pi} \sin(x) \, dx = 2
+\end{equation}
+
+\section{列表和项目}
+\subsection{无序列表}
+\begin{itemize}
+    \item 第一项包含\textbf{粗体文字}
+    \item 第二项包含\textit{斜体文字}
+    \item 第三项包含\textcolor{blue}{彩色文字}
+\end{itemize}
+
+\subsection{有序列表}
+\begin{enumerate}
+    \item 第一步
+    \item 第二步
+    \item 第三步
+\end{enumerate}
+
+\section{表格}
+\begin{table}[h]
+    \centering
+    \begin{tabular}{|c|c|c|}
+        \hline
+        姓名 & 年龄 & 城市 \\
+        \hline
+        张三 & 25 & 北京 \\
+        \hline
+        李四 & 30 & 上海 \\
+        \hline
+    \end{tabular}
+    \caption{简单表格示例}
+    \label{tab:simple}
+\end{table}
+
+\section{图形}
+您可以使用以下语法包含图形：
+
+% \begin{figure}[h]
+%     \centering
+%     \includegraphics[width=0.7\textwidth]{example-image}
+%     \caption{示例图形}
+%     \label{fig:example}
+% \end{figure}
+
+\section{引用文献}
+您可以使用 \verb|\cite{}| 命令引用参考文献 \cite{example}。
+
+\section{交叉引用}
+您可以使用 \verb|\ref{}| 命令引用章节、图形和表格。
+例如，参见表格~\ref{tab:simple}。
+
+\section{结论}
+这里是您的结论。
+
+% 示例参考文献条目
+\begin{thebibliography}{9}
+\bibitem{example} 作者姓名 (2023). \textit{书籍标题}. 出版社.
+\end{thebibliography}
+
+\end{document}
+"""
+
+# Default LaTeX template (English)
+default_template_english = r"""\documentclass{article}
 \usepackage[utf8]{inputenc}
 \usepackage{amsmath}
 \usepackage{amssymb}
@@ -265,27 +382,9 @@ An integral example:
     \label{tab:simple}
 \end{table}
 
-\section{Figures}
-You can include figures using the following syntax:
-
-% \begin{figure}[h]
-%     \centering
-%     \includegraphics[width=0.7\textwidth]{example-image}
-%     \caption{Example figure}
-%     \label{fig:example}
-% \end{figure}
-
-\section{Citations}
-You can cite references using the \verb|\cite{}| command \cite{example}.
-
-\section{Cross-References}
-You can reference sections, figures, and tables using the \verb|\ref{}| command. 
-For example, see Table~\ref{tab:simple}.
-
 \section{Conclusion}
 Your conclusion here.
 
-% Sample bibliography entry
 \begin{thebibliography}{9}
 \bibitem{example} Author, A. (2023). \textit{Title of the Work}. Publisher.
 \end{thebibliography}
@@ -293,7 +392,7 @@ Your conclusion here.
 \end{document}
 """
 
-# Enhanced VSCode-like styling
+# Enhanced VSCode-like styling (keeping the original styling)
 st.markdown("""
 <style>
     /* Base theming - VS Code inspired */
@@ -389,7 +488,36 @@ st.markdown("""
         color: #cca700;
     }
     
-    /* Outline view */
+    /* Engine status indicators */
+    .engine-status {
+        display: flex;
+        gap: 10px;
+        margin: 10px 0;
+        padding: 10px;
+        background-color: #252526;
+        border-radius: 4px;
+    }
+    
+    .engine-item {
+        display: flex;
+        align-items: center;
+        gap: 5px;
+        padding: 5px 10px;
+        border-radius: 3px;
+        font-size: 12px;
+    }
+    
+    .engine-available {
+        background-color: #1e3a1e;
+        color: #4caf50;
+    }
+    
+    .engine-unavailable {
+        background-color: #3a1e1e;
+        color: #f44336;
+    }
+    
+    /* All other existing styles remain the same */
     .outline-view {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -414,7 +542,6 @@ st.markdown("""
         margin-left: 5px;
     }
     
-    /* Download button styling */
     .download-button {
         display: inline-block;
         padding: 8px 16px;
@@ -432,7 +559,6 @@ st.markdown("""
         background-color: #4eb772;
     }
     
-    /* PDF preview area */
     .preview-container {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -441,7 +567,6 @@ st.markdown("""
         margin-top: 10px;
     }
     
-    /* Control panel */
     .control-panel {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -455,7 +580,6 @@ st.markdown("""
         gap: 5px;
     }
     
-    /* Messages */
     .stInfo {
         background-color: #063b49;
         color: #bbbbbb;
@@ -474,11 +598,9 @@ st.markdown("""
         border: 1px solid #1e5a3a;
     }
     
-    /* Hide Streamlit footer and menu */
     footer, header {display: none !important;}
     #MainMenu {visibility: hidden;}
     
-    /* Custom tabs */
     .stTabs [data-baseweb="tab-list"] {
         background-color: #2d2d2d;
         gap: 0px !important;
@@ -499,7 +621,6 @@ st.markdown("""
         color: white;
     }
     
-    /* Problems panel */
     .problems-panel {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -537,7 +658,6 @@ st.markdown("""
         margin-top: 2px;
     }
     
-    /* Document info panel */
     .document-info {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -564,7 +684,6 @@ st.markdown("""
         text-align: right;
     }
     
-    /* Packages panel */
     .packages-panel {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -593,7 +712,6 @@ st.markdown("""
         font-family: monospace;
     }
     
-    /* Environment analyzer */
     .environments-panel {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -620,7 +738,6 @@ st.markdown("""
         font-weight: bold;
     }
     
-    /* Simple keyboard shortcut */
     .shortcut-item {
         background-color: #252526;
         border: 1px solid #2d2d2d;
@@ -641,7 +758,6 @@ st.markdown("""
         margin-right: 10px;
     }
     
-    /* Monaco editor container */
     .monaco-editor-container {
         border: 1px solid #2d2d2d;
         border-radius: 4px;
@@ -649,7 +765,6 @@ st.markdown("""
         margin-bottom: 10px;
     }
     
-    /* Make sure Monaco editor has correct background */
     .monaco-editor, .monaco-editor-background, .monaco-editor .margin {
         background-color: #1e1e1e !important;
     }
@@ -667,17 +782,30 @@ def render_editor_tabs(active_tab="document.tex"):
     """
     st.markdown(tab_html, unsafe_allow_html=True)
 
-# VS Code-style status bar
-def render_status_bar():
-    status_html = """
+# VS Code-style status bar with engine info
+def render_status_bar(engine="XeLaTeX"):
+    status_html = f"""
     <div class="status-bar">
-        <span>LaTeX</span>
+        <span>{engine}</span>
         <span>Line: 1, Col: 1</span>
         <span>UTF-8</span>
     </div>
     """
     st.markdown(status_html, unsafe_allow_html=True)
 
+# Render engine status
+def render_engine_status():
+    engines = check_latex_engines()
+    
+    engine_html = '<div class="engine-status">'
+    for engine_name, available in engines.items():
+        status_class = "engine-available" if available else "engine-unavailable"
+        status_icon = "✅" if available else "❌"
+        engine_html += f'<div class="engine-item {status_class}">{status_icon} {engine_name}</div>'
+    engine_html += '</div>'
+    
+    st.markdown(engine_html, unsafe_allow_html=True)
+
 # Render a document outline based on section hierarchy
 def render_document_outline(structure):
     if not structure:
@@ -742,7 +870,7 @@ def render_problems(errors, warnings):
     st.markdown('</div>', unsafe_allow_html=True)
 
 # Render document information panel
-def render_document_info(latex_code):
+def render_document_info(latex_code, engine):
     # Ensure latex_code is a string
     if not isinstance(latex_code, str):
         try:
@@ -776,14 +904,19 @@ def render_document_info(latex_code):
     ref_count = len(re.findall(r'\\ref\{', latex_code))
     cite_count = len(re.findall(r'\\cite\{', latex_code))
     
+    # Check for Chinese characters
+    chinese_chars = len(re.findall(r'[\u4e00-\u9fff]', latex_code))
+    
     # Render the info panel
     st.markdown('<div class="document-info">', unsafe_allow_html=True)
     
     info_rows = [
+        ("LaTeX Engine", engine),
         ("Document Class", doc_class),
         ("Word Count", word_count),
         ("Character Count", char_count),
         ("Line Count", line_count),
+        ("Chinese Characters", chinese_chars),
         ("Equations", equation_count),
         ("Align Environments", align_count),
         ("Figures", figure_count),
@@ -864,7 +997,7 @@ def render_f5_shortcut():
 def main():
     # Initialize session state
     if 'latex_code' not in st.session_state:
-        st.session_state.latex_code = default_template
+        st.session_state.latex_code = default_template_chinese
     if 'show_preview' not in st.session_state:
         st.session_state.show_preview = False
     if 'last_compiled' not in st.session_state:
@@ -873,10 +1006,16 @@ def main():
         st.session_state.errors = []
     if 'warnings' not in st.session_state:
         st.session_state.warnings = []
+    if 'selected_engine' not in st.session_state:
+        st.session_state.selected_engine = 'xelatex'
+    
+    # Check available engines
+    engines = check_latex_engines()
+    available_engines = [engine for engine, available in engines.items() if available]
     
-    # Check installation status
-    if not is_pdflatex_installed():
-        st.warning("⚠️ LaTeX is not installed. The compilation feature will not work.")
+    if not available_engines:
+        st.error("⚠️ No LaTeX engines are installed. The compilation feature will not work.")
+        return
     
     # Create main layout
     col1, col2 = st.columns([3, 2])
@@ -898,7 +1037,7 @@ def main():
             if MONACO_AVAILABLE:
                 try:
                     # Try to use Monaco editor with minimal parameters
-                    latex_code = st_monaco(st.session_state.latex_code, height=500)
+                    latex_code = st_monaco(st.session_state.latex_code, height=500, language="latex")
                     if latex_code is not None:
                         st.session_state.latex_code = latex_code
                 except Exception as e:
@@ -913,18 +1052,22 @@ def main():
             
             st.markdown('</div>', unsafe_allow_html=True)
             
-            # Status bar
-            render_status_bar()
+            # Status bar with engine info
+            render_status_bar(st.session_state.selected_engine.upper())
             
             st.markdown('</div>', unsafe_allow_html=True)
             
+            # Engine status display
+            render_engine_status()
+            
             # F5 shortcut reminder
             render_f5_shortcut()
             
             # Control buttons with VS Code styling
             st.markdown('<div class="button-group">', unsafe_allow_html=True)
             compile_btn = st.button("Compile", help="Compile LaTeX to PDF (F5)")
-            load_template_btn = st.button("Load Template", help="Load default template")
+            load_chinese_btn = st.button("Load Chinese Template", help="Load Chinese template")
+            load_english_btn = st.button("Load English Template", help="Load English template")
             clear_btn = st.button("Clear", help="Clear editor content")
             st.markdown('</div>', unsafe_allow_html=True)
             
@@ -933,8 +1076,12 @@ def main():
                 st.session_state.compile_clicked = True
                 st.session_state.last_compiled = time.time()
             
-            if load_template_btn:
-                st.session_state.latex_code = default_template
+            if load_chinese_btn:
+                st.session_state.latex_code = default_template_chinese
+                st.rerun()
+            
+            if load_english_btn:
+                st.session_state.latex_code = default_template_english
                 st.rerun()
             
             if clear_btn:
@@ -948,8 +1095,17 @@ def main():
             col_a, col_b = st.columns(2)
             
             with col_a:
+                # Engine selection
+                if available_engines:
+                    selected_engine = st.selectbox(
+                        "LaTeX Engine", 
+                        available_engines,
+                        index=available_engines.index(st.session_state.selected_engine) if st.session_state.selected_engine in available_engines else 0,
+                        key="engine_select"
+                    )
+                    st.session_state.selected_engine = selected_engine
+                
                 st.checkbox("Auto-compile on save", value=False, key="auto_compile")
-                st.checkbox("Use pdflatex", value=True, key="use_pdflatex")
                 st.checkbox("Enable BibTeX", value=False, key="use_bibtex")
                 st.checkbox("Show line numbers", value=True, key="show_line_numbers")
             
@@ -957,13 +1113,25 @@ def main():
                 st.selectbox("Document Class", 
                              ["article", "report", "book", "letter", "beamer"], 
                              index=0, key="doc_class")
-                st.selectbox("PDF Engine", 
-                             ["pdflatex", "xelatex", "lualatex"], 
-                             index=0, key="pdf_engine")
+                st.selectbox("Font Selection",
+                            ["Noto CJK (Chinese)", "WQY (Chinese)", "Latin Modern (English)", "Times (English)"],
+                            index=0, key="font_selection")
                 st.selectbox("Editor Theme",
                             ["Dark", "Light", "High Contrast"],
                             index=0, key="editor_theme")
             
+            # Engine information
+            st.markdown("### Engine Information")
+            engine_info = {
+                'pdflatex': 'Traditional LaTeX engine, good for English documents',
+                'xelatex': 'Modern engine with Unicode support, excellent for Chinese and mixed languages',
+                'lualatex': 'Advanced engine with Lua scripting support, good for complex typography'
+            }
+            
+            for engine, description in engine_info.items():
+                status = "✅ Available" if engines.get(engine, False) else "❌ Not Available"
+                st.write(f"**{engine.upper()}**: {description} - {status}")
+            
             st.markdown('</div>', unsafe_allow_html=True)
     
     with col2:
@@ -974,7 +1142,7 @@ def main():
             # PDF compilation and output
             if 'compile_clicked' in st.session_state and st.session_state.compile_clicked:
                 with st.spinner("Compiling..."):
-                    pdf_data, stdout, stderr = latex_to_pdf(st.session_state.latex_code)
+                    pdf_data, stdout, stderr = latex_to_pdf(st.session_state.latex_code, st.session_state.selected_engine)
                     
                     # Parse errors and warnings
                     errors, warnings = parse_latex_errors(stdout + stderr)
@@ -983,7 +1151,7 @@ def main():
                     
                     if pdf_data:
                         st.session_state.pdf_data = pdf_data
-                        st.success("Compilation successful")
+                        st.success(f"Compilation successful using {st.session_state.selected_engine.upper()}")
                         
                         # Toggle button for preview
                         if st.button("Toggle Preview", help="Show or hide the PDF preview"):
@@ -995,7 +1163,7 @@ def main():
                         # Display compilation info
                         if st.session_state.last_compiled:
                             time_str = time.strftime("%H:%M:%S", time.localtime(st.session_state.last_compiled))
-                            st.info(f"Last compiled: {time_str}")
+                            st.info(f"Last compiled: {time_str} with {st.session_state.selected_engine.upper()}")
                         
                         # Optional preview
                         if st.session_state.show_preview:
@@ -1015,7 +1183,7 @@ def main():
                         
                         st.session_state.compile_clicked = False
                     else:
-                        st.error("Compilation failed")
+                        st.error(f"Compilation failed with {st.session_state.selected_engine.upper()}")
                         st.markdown('<div class="terminal">', unsafe_allow_html=True)
                         
                         # Highlight errors in output
@@ -1042,7 +1210,7 @@ def main():
                 # Display compilation info
                 if st.session_state.last_compiled:
                     time_str = time.strftime("%H:%M:%S", time.localtime(st.session_state.last_compiled))
-                    st.info(f"Last compiled: {time_str}")
+                    st.info(f"Last compiled: {time_str} with {st.session_state.selected_engine.upper()}")
                 
                 # Optional preview
                 if st.session_state.show_preview:
@@ -1066,13 +1234,13 @@ def main():
             if structure:
                 render_document_outline(structure)
             else:
-                st.info("No document structure detected. Add sections using the toolbar.")
+                st.info("No document structure detected. Add sections using \\section{}, \\subsection{}, etc.")
         
         with output_tabs[2]:
             # Document analysis features
             
             # Document info
-            render_document_info(st.session_state.latex_code)
+            render_document_info(st.session_state.latex_code, st.session_state.selected_engine.upper())
             
             # Package analysis
             packages = analyze_packages(st.session_state.latex_code)