FROM alpine:latest

# Install vsftpd and netcat for healthcheck
RUN apk update && \
    apk add --no-cache vsftpd netcat-openbsd && \
    rm -rf /var/cache/apk/*

# Create FTP directory for anonymous users and log directory
RUN mkdir -p /var/ftp/pub /var/log && \
    chmod 755 /var/ftp/pub && \
    chown ftp:ftp /var/ftp/pub && \
    touch /var/log/xferlog /var/log/vsftpd.log && \
    chmod 666 /var/log/xferlog /var/log/vsftpd.log

# Create a test file for anonymous downloads
COPY welcome.txt /var/ftp/pub/welcome.txt
RUN chown ftp:ftp /var/ftp/pub/welcome.txt

# Configure vsftpd for anonymous access
COPY vsftpd.conf /etc/vsftpd/vsftpd.conf

# Expose FTP port and passive mode ports
EXPOSE 21 21100-21110

# Start vsftpd in foreground mode and tail logs to stdout
CMD sh -c "vsftpd /etc/vsftpd/vsftpd.conf & tail -f /var/log/xferlog /var/log/vsftpd.log 2>/dev/null & wait"