Architecture

System Overview

graph TB
    subgraph Frontend ["Vue 3 Frontend"]
        A[TranslateView] --> B[FileTranslateView]
        C[HistoryView] --> D[DashboardView]
        E[SettingsView] --> F[ModelsView]
    end

    subgraph Backend ["FastAPI Backend"]
        G[API Routes] --> H[Translation Service]
        G --> I[History Service]
        G --> J[Export Service]
        H --> K[Ollama Service]
        G --> L[Streaming SSE]
    end

    subgraph Data ["Data Layer"]
        M[(SQLite DB)]
        N[File System]
    end

    subgraph LLM ["LLM Engine"]
        O[Ollama Server]
        P[Local Models]
    end

    Frontend -->|REST + SSE| Backend
    I --> M
    J --> N
    K --> O
    O --> P

Tech Stack

Layer	Technology
Frontend	Vue 3, Vite, TypeScript, Pinia, Vue Router, TailwindCSS v4, Lucide Icons, vue-i18n
Backend	Python 3.12, FastAPI, SQLAlchemy (async), Pydantic v2
Database	SQLite via aiosqlite
LLM	Translation Integration
File Processing	PyMuPDF, RapidOCR, python-docx, openpyxl, pandas
Packaging	PyInstaller, Docker, GitHub Actions
System Dialogs	os_integration.py (Zenity, kdialog, osascript, PowerShell)

Key Design Decisions

• SSE streaming for real-time translation output (not WebSocket — simpler, one-directional)
• SPA with middleware fallback — FastAPI serves Vue app with a custom SPAFallbackMiddleware for client-side routing
• Cross-platform native dialogs — OS-specific file dialogs (kdialog, zenity, osascript, PowerShell) instead of heavy Qt/Electron dependencies