# SparkOS Docker Image
# Multi-stage build for minimal final image size

# Build stage - use gcc image which has all build tools pre-installed
FROM gcc:13-bookworm AS builder

# Set working directory
WORKDIR /build

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

# Build the init system
RUN make init

# Runtime stage - use Alpine for minimal size
FROM alpine:3.19

# Install file command for testing init binary
# file package provides the file(1) command to determine file type
RUN apk add --no-cache file

# Note: Alpine includes busybox by default

# Create minimal rootfs structure
RUN mkdir -p /sparkos/rootfs/bin \
    /sparkos/rootfs/sbin \
    /sparkos/rootfs/etc \
    /sparkos/rootfs/proc \
    /sparkos/rootfs/sys \
    /sparkos/rootfs/dev \
    /sparkos/rootfs/tmp \
    /sparkos/rootfs/usr/bin \
    /sparkos/rootfs/usr/sbin \
    /sparkos/rootfs/usr/lib \
    /sparkos/rootfs/var/log \
    /sparkos/rootfs/var/run \
    /sparkos/rootfs/root \
    /sparkos/rootfs/home/spark && \
    chmod 1777 /sparkos/rootfs/tmp && \
    chmod 700 /sparkos/rootfs/root && \
    chmod 755 /sparkos/rootfs/home/spark

# Copy built init binary from builder
COPY --from=builder /build/init /sparkos/rootfs/sbin/init

# Set up basic configuration files
RUN echo "sparkos" > /sparkos/rootfs/etc/hostname && \
    echo "127.0.0.1   localhost" > /sparkos/rootfs/etc/hosts && \
    echo "127.0.1.1   sparkos" >> /sparkos/rootfs/etc/hosts && \
    echo "root:x:0:0:root:/root:/bin/sh" > /sparkos/rootfs/etc/passwd && \
    echo "spark:x:1000:1000:SparkOS User:/home/spark:/bin/sh" >> /sparkos/rootfs/etc/passwd && \
    echo "root:x:0:" > /sparkos/rootfs/etc/group && \
    echo "spark:x:1000:" >> /sparkos/rootfs/etc/group

# Create a test entrypoint
COPY scripts/test.sh /sparkos/test.sh
RUN chmod +x /sparkos/test.sh

WORKDIR /sparkos

# Set entrypoint
ENTRYPOINT ["/sparkos/test.sh"]