Процесс загрузки книги после нажатия «Загрузить книгу»

flowchart LR
    A[Выбор файла] --> B[Кнопка «Загрузить книгу»]
    B --> C[Клик]
    C --> D[handleUpload]

flowchart TD
    H[handleUpload] --> D[FormData]
    D --> D1[formData.append 'file', selectedFile]
    H --> X[XHR]
    X --> X1[POST /api/book-upload]
    X --> X2[Header X-Telegram-Init-Data]
    X --> X3[progress → progressFill, progressText]
    X --> X4[xhr.send formData]

flowchart TD
    API[POST /api/book-upload] --> MW1[checkTelegramAccess]
    MW1 --> MW2[upload.single 'file']
    MW2 --> R[Роут-обработчик]
    
    MW1 --> V[validateTelegramInitData]
    V --> S[Subscriber + User isEmployee]
    S --> OK[req.telegramUser, req.subscriber]

flowchart LR
    subgraph Извлечение
        F[req.file.buffer] --> PDF[PDF: extractTextFromPdf 5 стр.]
        F --> EPUB[EPUB: extractTextFromEpub 3 гл.]
        PDF --> T1[extractedText]
        EPUB --> T1
        EPUB --> M[title, author из OPF]
    end
    
    subgraph Анализ
        T1 --> AI[bookService.analyzeBook]
        AI --> AN[title, author, description]
    end
    
    subgraph Обложка
        AN --> COV[searchBookCover]
        COV --> R2C[uploadCoverToR2]
    end
    
    subgraph Данные книги
        AN --> BD[bookData]
        M --> BD
        R2C --> BD
    end

flowchart TD
    subgraph Хранилище
        BUF[file.buffer] --> R2[bookService.uploadBookFileToR2]
        R2 --> KEY[books/pdf|epub/timestamp_hex_name]
        KEY --> R2B[(Cloudflare R2)]
        R2B --> FILE_URL[fileUrl]
    end
    
    subgraph База
        FILE_URL --> BOOK[bookData.pdfUrl | bookData.epubUrl]
        EX[findExistingBook] --> UP{existingBook?}
        UP -->|Да| UPDATE[existingBook.update]
        UP -->|Нет| CREATE[Book.create]
        UPDATE --> SAVED[savedBook]
        CREATE --> SAVED
    end
    
    subgraph Ответ и уведомления
        SAVED --> RES[res.json success, title, author, bookId]
        SAVED --> TG[sendTelegramNotification]
        TG --> BOT[BOOK_LIBRARY_BOT_TOKEN]
    end

flowchart TB
    subgraph Триггер
        T1[Кнопка «Загрузить книгу»]
    end
    
    subgraph Обработчик_клиент
        T1 --> H[handleUpload]
        H --> FD[FormData + file]
        FD --> XHR[XHR POST /api/book-upload]
    end
    
    subgraph Запрос_API
        XHR --> AUTH[checkTelegramAccess]
        AUTH --> MUL[multer.single 'file']
        MUL --> ROUTE[Роут POST /]
    end
    
    subgraph Форматирование
        ROUTE --> EXTRACT[extractText PDF/EPUB]
        EXTRACT --> ANALYZE[analyzeBook]
        ANALYZE --> COVER[searchBookCover + uploadCoverToR2]
        COVER --> BOOK_DATA[bookData]
    end
    
    subgraph Отправка
        BOOK_DATA --> R2[uploadBookFileToR2]
        R2 --> DB[(Book create/update)]
        DB --> RES[res.json]
        DB --> TG[Telegram уведомление]
    end
    
    Триггер --> Обработчик_клиент
    Обработчик_клиент --> Запрос_API
    Запрос_API --> Форматирование
    Форматирование --> Отправка