# Zero OS Alpine Initramfs Builder Container
FROM alpine:3.22

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

# Create musl-gcc wrapper (Alpine's gcc already targets musl)
RUN echo '#!/bin/sh' > /usr/bin/musl-gcc && \
    echo 'exec gcc -static "$@"' >> /usr/bin/musl-gcc && \
    chmod +x /usr/bin/musl-gcc && \
    which musl-gcc

# Create non-root user for builds matching host user
RUN adduser -D -s /bin/bash builder

# Set working directory with proper permissions
WORKDIR /workspace
RUN chown builder:builder /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"

# Don't switch to builder user yet - let the runtime handle it

CMD ["/bin/bash"]