#!/bin/bash
# RHEL Build Normalization Script
# Sprint: SPRINT_1227_0002_0001 (Reproducible Builders)
#
# Normalizes RPM build environment for reproducibility

set -euo pipefail

# Normalize environment
export TZ=UTC
export LC_ALL=C.UTF-8
export LANG=C.UTF-8

# Deterministic compiler flags
export CFLAGS="${CFLAGS:--fno-record-gcc-switches -fdebug-prefix-map=$(pwd)=/buildroot -O2 -g}"
export CXXFLAGS="${CXXFLAGS:-${CFLAGS}}"

# Disable debug info that varies
export DEB_BUILD_OPTIONS="nostrip noopt"

# RPM-specific reproducibility
export RPM_BUILD_NCPUS=1

# Normalize timestamps in archives
normalize_ar() {
    local archive="$1"
    if command -v llvm-ar &>/dev/null; then
        llvm-ar --format=gnu --enable-deterministic-archives rcs "${archive}.new" "${archive}"
        mv "${archive}.new" "${archive}"
    fi
}

# Normalize timestamps in tar archives
normalize_tar() {
    local archive="$1"
    local mtime="${SOURCE_DATE_EPOCH:-0}"
    
    # Repack with deterministic settings
    local tmp_dir=$(mktemp -d)
    tar -xf "${archive}" -C "${tmp_dir}"
    tar --sort=name \
        --mtime="@${mtime}" \
        --owner=0 --group=0 \
        --numeric-owner \
        -cf "${archive}.new" -C "${tmp_dir}" .
    mv "${archive}.new" "${archive}"
    rm -rf "${tmp_dir}"
}

# Normalize __pycache__ timestamps
normalize_python() {
    find . -name '__pycache__' -type d -exec rm -rf {} + 2>/dev/null || true
    find . -name '*.pyc' -delete 2>/dev/null || true
}

# Strip build paths from binaries
strip_build_paths() {
    local binary="$1"
    if command -v objcopy &>/dev/null; then
        # Remove .note.gnu.build-id if it contains build path
        objcopy --remove-section=.note.gnu.build-id "${binary}" 2>/dev/null || true
    fi
}

# Main normalization
normalize_build() {
    echo "Normalizing build environment..."
    
    # Normalize Python bytecode
    normalize_python
    
    # Find and normalize archives
    find . -name '*.a' -type f | while read -r ar; do
        normalize_ar "${ar}"
    done
    
    echo "Normalization complete"
}

# If sourced, export functions; if executed, run normalization
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
    normalize_build
fi