Enhance document conversion capabilities by adding support for additional ebook formats (MOBI, AZW, AZW3, FB2) and integrating Calibre for conversions. Update README.md with installation instructions for Calibre and modify tests to cover new conversion scenarios.

Author: sametcn99

README.md

@@ -60,29 +60,37 @@ Terminal-based file converter built with Go. It provides a modern, user-friendly
 
 ### Documents
 
-| Input                  | Output                          |
-|------------------------|---------------------------------|
-| `.pdf`, `.md`, `.html` | `.pdf`, `.md`, `.html`, `.epub` |
-| `.csv`                 | `.xlsx`                         |
-| `.xlsx`, `.xls`        | `.csv`                          |
+| Input                                     | Output                                                                    |
+|-------------------------------------------|---------------------------------------------------------------------------|
+| `.pdf`, `.md`, `.html`                    | `.pdf`, `.md`, `.html`, `.epub`, `.mobi`, `.azw`, `.azw3`, `.fb2`         |
+| `.epub`, `.mobi`, `.azw`, `.azw3`, `.fb2` | `.epub`, `.mobi`, `.azw`, `.azw3`, `.fb2`, `.pdf`, `.html`, `.txt`, `.md` |
+| `.csv`                                    | `.xlsx`                                                                   |
+| `.xlsx`, `.xls`                           | `.csv`                                                                    |
 
 **Features:**
 
 - PDF text extraction to Markdown
 - Markdown to styled HTML with responsive design
 - Markdown/HTML to EPUB conversion
+- EPUB/MOBI/AZW/AZW3/FB2 conversions via Calibre (if installed)
 - PDF compression/optimization
 - CSV to Excel conversion with styled headers and auto-fit columns
 - Excel to CSV export (exports first sheet)
 
-> **Note:** Video and audio conversion requires `ffmpeg` to be installed on your system.
+> **Note:** Video and audio conversion requires `ffmpeg`. Ebook conversions beyond EPUB require Calibre's `ebook-convert`.
+
+**PATH Note (ebook-convert):**
+- **Linux:** Typically available at `/usr/bin/ebook-convert` (or `/snap/bin/ebook-convert`). Ensure the directory is on `PATH`.
+- **macOS (Homebrew):** `/opt/homebrew/bin/ebook-convert` (Apple Silicon) or `/usr/local/bin/ebook-convert` (Intel).
+- **Windows:** `C:\Program Files\Calibre2\ebook-convert.exe` (or `C:\Program Files (x86)\Calibre2\ebook-convert.exe`). Add the folder to `PATH` if not detected.
 
 ## Installation
 
 ### Prerequisites
 
 - **Go 1.21+**
 - **ffmpeg** (required for video/audio conversion)
+- **Calibre (ebook-convert)** (required for ebook conversions beyond EPUB)
 
 ### Quick Install
 
@@ -121,13 +129,13 @@ task build
 
 ```bash
 # Ubuntu/Debian
-sudo apt update && sudo apt install ffmpeg
+sudo apt update && sudo apt install ffmpeg calibre
 
 # Fedora
-sudo dnf install ffmpeg
+sudo dnf install ffmpeg calibre
 
 # Arch Linux
-sudo pacman -S ffmpeg
+sudo pacman -S ffmpeg calibre
 
 # Build
 go build -o golter main.go
@@ -145,6 +153,9 @@ go build -o golter main.go
 # Install ffmpeg
 brew install ffmpeg
 
+# Install Calibre (ebook-convert)
+brew install --cask calibre
+
 # Build
 go build -o golter main.go
 
@@ -161,9 +172,15 @@ go build -o golter main.go
 # Using winget
 winget install ffmpeg
 
+# Calibre (ebook-convert)
+winget install calibre.calibre
+
 # Or using chocolatey
 choco install ffmpeg
 
+# Calibre (ebook-convert)
+choco install calibre
+
 # Build
 go build -o golter.exe main.go
 

go.mod

@@ -12,6 +12,7 @@ require (
 	github.com/go-pdf/fpdf v0.9.0
 	github.com/ledongthuc/pdf v0.0.0-20250511090121-5959a4027728
 	github.com/pdfcpu/pdfcpu v0.11.1
+	github.com/taylorskalyo/goreader v1.0.1
 	github.com/xuri/excelize/v2 v2.10.0
 	github.com/yuin/goldmark v1.7.16
 )

go.sum

@@ -100,6 +100,8 @@ github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UV
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
 github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+github.com/taylorskalyo/goreader v1.0.1 h1:eS9SYiHai2aAHhm+YMGRTqrvNt2aoRMTd7p6ftm0crY=
+github.com/taylorskalyo/goreader v1.0.1/go.mod h1:JrUsWCgnk4C3P5Jsr7Pf2mFrMpsR0ls/0bjR5aorYTI=
 github.com/tiendc/go-deepcopy v1.7.1 h1:LnubftI6nYaaMOcaz0LphzwraqN8jiWTwm416sitff4=
 github.com/tiendc/go-deepcopy v1.7.1/go.mod h1:4bKjNC2r7boYOkD2IOuZpYjmlDdzjbpTRyCx+goBCJQ=
 github.com/vincent-petithory/dataurl v0.0.0-20191104211930-d1553a71de50 h1:uxE3GYdXIOfhMv3unJKETJEhw78gvzuQqRX/rVirc2A=