build-portable.sh

#!/usr/bin/env bash
# Cross-platform build script for BEX Engine
# Targets GLIBC 2.31+ (Ubuntu 20.04 / Debian 11 / most modern distros)
#
# Strategy: Use musl-static or manylinux2_28 build environment
# This ensures the resulting binary works on:
#   - Ubuntu 20.04+
#   - Debian 11+
#   - Fedora 34+
#   - Alpine (musl)
#   - RHEL 8+
#   - Any system with GLIBC >= 2.28
#
# Usage:
#   ./build-portable.sh          # Build dynamically linked (GLIBC 2.28+)
#   ./build-portable.sh --musl   # Build fully static (no GLIBC dependency)
#   ./build-portable.sh --docker # Build in Docker for reproducibility
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"

BUILD_MODE="${1:-dynamic}"
OUTPUT_DIR="dist"
mkdir -p "$OUTPUT_DIR"

echo "=== BEX Engine Portable Build ==="
echo "Mode: $BUILD_MODE"
echo ""

case "$BUILD_MODE" in
    --musl|musl)
        echo "Building fully static binary (musl)..."
        echo "This produces a binary with ZERO system library dependencies."
        echo ""

        # Ensure musl target is installed
        rustup target add x86_64-unknown-linux-musl 2>/dev/null || true

        # Build with musl (fully static)
        RUSTFLAGS="-C target-feature=+crt-static" \
        cargo build --release --target x86_64-unknown-linux-musl

        cp target/x86_64-unknown-linux-musl/release/bex "$OUTPUT_DIR/bex"
        cp target/x86_64-unknown-linux-musl/release/libbex_runtime.a "$OUTPUT_DIR/libbex_runtime.a"

        echo ""
        echo "Built static binary: $OUTPUT_DIR/bex"
        echo "No GLIBC dependency — runs on any Linux x86_64"
        ;;

    --docker|docker)
        echo "Building in Docker (manylinux2_28 / GLIBC 2.28)..."
        echo "This produces a binary compatible with all modern Linux distros."
        echo ""

        # Use a Debian 11 (Bullseye) based image for GLIBC 2.31
        docker run --rm -v "$SCRIPT_DIR:/src" -w /src \
            rust:1.79-bullseye \
            bash -c '
                apt-get update -qq && apt-get install -y -qq pkg-config libssl-dev >/dev/null 2>&1
                cargo build --release
                cp target/release/bex /src/dist/bex
                cp target/release/libbex_runtime.so /src/dist/libbex_runtime.so 2>/dev/null || true
                cp target/release/libbex_runtime.a /src/dist/libbex_runtime.a 2>/dev/null || true
            '

        echo ""
        echo "Built with GLIBC 2.31 (Debian 11 Bullseye)"
        echo "Compatible with: Ubuntu 20.04+, Debian 11+, Fedora 34+, RHEL 8+"
        ;;

    *)
        echo "Building with system toolchain..."
        echo ""

        cargo build --release

        cp target/release/bex "$OUTPUT_DIR/bex" 2>/dev/null || true
        cp target/release/libbex_runtime.so "$OUTPUT_DIR/libbex_runtime.so" 2>/dev/null || true
        cp target/release/libbex_runtime.a "$OUTPUT_DIR/libbex_runtime.a" 2>/dev/null || true

        # Check GLIBC version requirement
        if command -v objdump &>/dev/null; then
            echo ""
            echo "GLIBC version requirements:"
            objdump -T "$OUTPUT_DIR/bex" 2>/dev/null | grep GLIBC_ | sed 's/.*GLIBC_/GLIBC_/' | sort -Vu || true
        fi
        ;;
esac

echo ""
echo "=== Build Complete ==="
ls -la "$OUTPUT_DIR/bex" "$OUTPUT_DIR/libbex_runtime"* 2>/dev/null
echo ""

# Verify the binary
if [ -f "$OUTPUT_DIR/bex" ]; then
    echo "Binary info:"
    file "$OUTPUT_DIR/bex" 2>/dev/null || true
    echo ""

    # Quick sanity test
    if "$OUTPUT_DIR/bex" --help >/dev/null 2>&1; then
        echo "✓ Binary runs successfully on this system"
    else
        echo "⚠ Binary may not run on this system (different GLIBC)"
        echo "  Use --musl for a fully static build, or --docker for GLIBC 2.31"
    fi
fi