# Dockerfile for building SparkOS bootable image
# This creates a .img file that can be written to USB drives

FROM ubuntu:22.04 AS image-builder

# Install required tools
RUN apt-get update && \
    apt-get install -y \
    gcc \
    make \
    dosfstools \
    mtools \
    xorriso \
    isolinux \
    syslinux \
    syslinux-common \
    e2fsprogs \
    parted \
    kpartx \
    && rm -rf /var/lib/apt/lists/*

WORKDIR /build

# Copy source files
COPY src/ ./src/
COPY Makefile .
COPY scripts/ ./scripts/
COPY config/ ./config/
COPY rootfs/ ./rootfs/

# Build the init binary
RUN make init

# Create the bootable image
# We'll use a simpler approach that works in Docker
RUN mkdir -p /output && \
    echo "Building minimal bootable image..." && \
    # Create a minimal image with just the init system for now
    # This is a placeholder - the actual bootloader requires a kernel
    dd if=/dev/zero of=/output/sparkos.img bs=1M count=512 && \
    mkfs.ext4 -L SparkOS /output/sparkos.img && \
    mkdir -p /mnt/img && \
    mount -o loop /output/sparkos.img /mnt/img && \
    mkdir -p /mnt/img/{bin,sbin,etc,proc,sys,dev,tmp,usr/{bin,sbin,lib},var/{log,run},root,home/spark,boot} && \
    cp init /mnt/img/sbin/init && \
    chmod 755 /mnt/img/sbin/init && \
    # Create basic config files
    echo "sparkos" > /mnt/img/etc/hostname && \
    echo "127.0.0.1   localhost" > /mnt/img/etc/hosts && \
    echo "127.0.1.1   sparkos" >> /mnt/img/etc/hosts && \
    echo "root:x:0:0:root:/root:/bin/sh" > /mnt/img/etc/passwd && \
    echo "spark:x:1000:1000:SparkOS User:/home/spark:/bin/sh" >> /mnt/img/etc/passwd && \
    echo "root:x:0:" > /mnt/img/etc/group && \
    echo "spark:x:1000:" >> /mnt/img/etc/group && \
    # Create README
    cat > /mnt/img/README.txt << 'EOF' && \
SparkOS Minimal Filesystem Image

This is a minimal ext4 filesystem image containing the SparkOS init system.
This is NOT a fully bootable image - it requires additional components.

What's included:
- SparkOS init binary (/sbin/init)
- Basic FHS-compliant directory structure
- Basic configuration files

To make this fully bootable, you need to add:
1. Linux kernel (install to /boot/vmlinuz)
2. Busybox (install to /bin/busybox and create symlinks)
3. Bootloader (GRUB or syslinux)
4. Required libraries (if using dynamically linked binaries)

This image can be mounted to extract the init binary or inspect the structure:
  sudo mount -o loop sparkos.img /mnt
  cp /mnt/sbin/init ./
  sudo umount /mnt

For more information, see: https://github.com/johndoe6345789/SparkOS
EOF
    sync && \
    umount /mnt/img && \
    # Compress the image
    gzip -9 /output/sparkos.img && \
    echo "Image created: /output/sparkos.img.gz"

# Final stage - just export the image
FROM scratch AS export
COPY --from=image-builder /output/sparkos.img.gz /sparkos.img.gz