# Zero OS Alpine Initramfs Builder Container
FROM alpine:3.22

# Install build dependencies
RUN apk add --no-cache \
    build-base \
    rust \
    cargo \
    upx \
    git \
    wget \
    tar \
    gzip \
    xz \
    cpio \
    binutils \
    linux-headers \
    musl-dev \
    pkgconfig \
    openssl-dev \
    bash \
    findutils \
    grep \
    sed \
    coreutils

# Install musl-dev for Rust musl targeting (Alpine handles this differently than rustup)
RUN apk add --no-cache musl-dev

# Create non-root user for builds
RUN adduser -D -s /bin/bash builder && \
    chown -R builder:builder /home/builder

# Set working directory
WORKDIR /workspace

# Set environment variables for musl static linking with Alpine's Rust
ENV RUSTFLAGS="-C target-feature=+crt-static -C linker=musl-gcc"
ENV CC="musl-gcc"
ENV TARGET_CC="musl-gcc"
ENV CARGO_TARGET_X86_64_UNKNOWN_LINUX_MUSL_LINKER="musl-gcc"

# Default to builder user
USER builder

CMD ["/bin/bash"]