#!/bin/bash
# BTC-0.2.0.sh - Build Tool Chain
# Version: 0.2.0 (Sovereign Sentry Forge / dcosnet-Identity / Swarm-Aware)
# Target: Dell Optiplex 3050 Micro Variants & RDIMM Swarm
# License: GNU Affero General Public License v3 (AGPL-3.0)
#
# Notwithstanding any other provision of this License, if you modify
# the Program, your modified version must prominently offer all users
# interacting with it remotely through a computer network an
# opportunity to receive the Corresponding Source of your version.
#
# Security: CVE-2026-31431 Mitigated | PATH-Pinned | Static-Trust Ready
# Persistence: /opt/BTC | Volatile: ramfs
# Copyright (C) 2012-2026 Jeremy Anderson (info@dcos.net)

# --- 1. AGPL COMPLIANCE & IDENTITY ---
function f_agpl_header() {
    cat <<EOF
>> BTC-0.2.0 "Sovereign Sentry"
>> Copyright (C) 2026 Jeremy Anderson
>> Licensed under GNU AGPLv3. NO WARRANTY.
>> SOURCE: https://dcos.net/git/btc (Official Mirror)
>> -----------------------------------------------------
EOF
}

# --- 2. HARDENED ENVIRONMENT ---
# Reset PATH to prevent environment poisoning/hijacking
export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
set -euo pipefail # Strict error propagation
set -f           # Disable globbing to prevent unintended expansion

# Toolchain Aliases: Pinning absolute paths to avoid "Copy Fail" hijacked binaries
alias rsync='/usr/bin/rsync'
alias tar='/usr/bin/tar'
alias gcc='/usr/bin/gcc'
alias sha256sum='/usr/bin/sha256sum'

# --- 3. RECOVERY & CLEANUP ---
# Trap ensures ramfs is unmounted even if build fails; prevents persistent memory bloat
trap "echo '>> Interrupt: Cleaning ramfs...'; cd / && umount -l ${SOURCES_ACTIVE} 2>/dev/null || true; exit 1" INT TERM

# --- 4. GLOBAL CONFIG ---
export BTC_DEBUG_LEVEL=1  
export BTC_STRIP_MODE=1   
export BTC_ARCHIVE=/opt/BTC 
export SOURCES_ACTIVE=/usr/src
export SOURCE_CACHE=${BTC_ARCHIVE}/src
export v_glibc='glibc-2.41'
export v_gcc='gcc-14.2.0'
export v_binutils='binutils-2.46'
export v_linux='linux-7.1'
export NEWROOT=${SOURCES_ACTIVE}/BTC-Forge
export LOGS=${NEWROOT}/LOGS
export DISTRO="DCOSNET-LEAD"

# --- 5. SILICON IDENTITY & MITIGATION ---
function f_silicon_probe() {
    echo ">> [IDENTITY] Interrogating Silicon..."
    
    # Mitigate CVE-2026-31431: Disable vulnerable crypto socket before forge starts
    if [[ -f /proc/modules ]] && grep -q "algif_aead" /proc/modules; then
        echo ">> [SECURITY] Disabling algif_aead (Copy Fail mitigation)..."
        rmmod algif_aead || true
    fi

    local RAW_ARCH=$(/usr/bin/gcc -march=native -Q --help=target | grep -m1 "march=" | awk '{print $2}')
    [[ -z "$RAW_ARCH" || "$RAW_ARCH" == "x86-64" ]] && export TARGET_ARCH="hsw" || export TARGET_ARCH="bdw"
    
    export ISA_TAG="AVX2"
    export OPT_TAG="LTO"
    export SYS_LABEL="DCOSNET-${TARGET_ARCH^^}-${ISA_TAG}-${OPT_TAG}"
    export TARGET="x86_64-dcosnet-linux-gnu" 
    
    # Calculate thread depth: 2GB RAM floor per core for LTO safety
    local total_ram=$(/usr/bin/free -m | awk '/^Mem:/{print $2}')
    export v_threads="-j$(( (total_ram / 2048) < $(nproc) ? (total_ram / 2048) : $(nproc) ))"

    # Aggressive Forge Profile: O3 + LTO + Hardened Stack
    export GLOBAL_CFLAGS="-O3 -march=native -flto=$(nproc) -fstack-protector-strong -D_FORTIFY_SOURCE=2 --sysroot=${NEWROOT} -pipe"
    export GLOBAL_LDFLAGS="-Wl,-O1 -Wl,--as-needed -flto=$(nproc) --sysroot=${NEWROOT}"
    
    export CCACHE_DIR="${BTC_ARCHIVE}/cache/${SYS_LABEL}"
    mkdir -p "${CCACHE_DIR}"
}

# --- 6. DCOSNET FORENSIC STAMPING (ELF & XATTR) ---
function f_stamp_binary() {
    local target_bin="$1"
    local log_base="$2"
    
    # Inject Immutable ELF Note (The Silicon DNA)
    cat <<EOF > btc_stamp.s
.section .note.BTC,"a"
.align 4
.long 4f - 1f
.long 3f - 2f
.long 1
1: .asciz "DCOSNET"
2: .ascii "Org: dcos.net|K:7.1|I:${ISA_TAG}|O:${OPT_TAG}|T:${DISTRO}|F:${HOSTNAME}"
3: .align 4
4:
EOF
    /usr/bin/gcc -c btc_stamp.s -o btc_stamp.o
    objcopy --add-section .note.BTC=btc_stamp.o "${target_bin}"
    rm btc_stamp.s btc_stamp.o

    # Rapid Audit Metadata for Fapolicyd/eBPF verification
    local bin_hash=$(sha256sum "${target_bin}" | awk '{print $1}')
    setfattr -n user.btc.identity -v "BTC-${SYS_LABEL}-${v_linux}-dcosnet" "${target_bin}"
    setfattr -n user.btc.hash -v "${bin_hash}" "${target_bin}"
    
    # Extract debug symbols to LeadNode archive before thinning binary
    if [[ "${BTC_STRIP_MODE}" -eq 1 ]]; then
        mkdir -p "${BTC_ARCHIVE}/symbols/${SYS_LABEL}"
        objcopy --only-keep-debug "${target_bin}" "${BTC_ARCHIVE}/symbols/${SYS_LABEL}/${log_base}.debug"
        strip --strip-unneeded "${target_bin}"
        objcopy --add-gnu-debuglink="${BTC_ARCHIVE}/symbols/${SYS_LABEL}/${log_base}.debug" "${target_bin}"
    fi
}

# --- 7. THE INVISIBLE GUARD ---
function f_guard() {
    local max_temp=85
    local min_mem=800
    while true; do
        local cur_temp=$(cat /sys/class/thermal/thermal_zone*/temp | head -n1 | awk '{print $1/1000}')
        local cur_mem=$(/usr/bin/free -m | awk '/^Mem:/{print $7}')
        if (( cur_temp > max_temp )); then 
            echo ">> [THERMAL PAUSE] ${cur_temp}°C - Cooling..."
            sleep 10
        elif (( cur_mem < min_mem )); then 
            echo ">> [MEMORY PAUSE] ${cur_mem}MB - Waiting for LTO clearance (RDIMM)..."
            sleep 30
        else 
            break
        fi
    done
}

function f_entropy_shield() {
    local cur_ent=$(cat /proc/sys/kernel/random/entropy_avail)
    if (( cur_ent < 250 )); then
        echo ">> [ENTROPY SHIELD] Low Pool. Generating Jitter for 7.1 Signing..."
        find /bin /sbin -type f -exec ls -l {} + > /dev/null 2>&1 &
        sleep 2 && kill $! 2>/dev/null || true
    fi
}

# --- 8. EXECUTION ENGINE (FORENSIC) ---
function f_exec_log() {
    local cmd="$1"
    local log_base="$2"
    local mode="${3:-build}" 
    
    f_entropy_shield
    f_guard

    if [[ "$mode" == "install" ]]; then
        # Audit FS changes via installwatch; triggers binary stamping
        stdbuf -oL -eL installwatch -o "${LOGS}/${log_base}.iw" bash -c "$cmd" | \
        pv -t -r -b -N "${log_base}" >> "${LOGS}/${log_base}.log" 2>&1
        
        find ${NEWROOT} -type f -executable -exec bash -c '
            file "$1" | grep -q "ELF" && f_stamp_binary "$1" "'"${log_base}"'"
        ' _ {} \;
    else
        # Standard build: pipe stdout through pv for telemetry; separate stderr
        stdbuf -oL -eL bash -c "${cmd}" | \
        pv -t -r -b -N "${log_base}" | \
        tee -a "${LOGS}/${log_base}.log" > /dev/null \
        2> >(tee -a "${LOGS}/${log_base}.err" >> "${LOGS}/${log_base}.log")
    fi
}

function f_setup() {
    # Mount Volatile Ramfs: The "Forge Stage" Cleanroom
    local ram_kb=$(grep MemTotal /proc/meminfo | awk '{print $2}')
    mount -t ramfs -o size=$((ram_kb/2/1024))M ramfs ${SOURCES_ACTIVE}
    mkdir -p ${NEWROOT}/{bin,lib,lib64,sbin,etc,usr,boot} ${LOGS}
    ln -sf lib ${NEWROOT}/lib64
    
    # Tmux dashboard for real-time telemetry observation
    if [[ -n "${TMUX:-}" ]]; then
        tmux split-window -h -p 35 "tail -F ${LOGS}/*.log 2>/dev/null"
        tmux split-window -v -p 66 "watch -n 2 'ss -tunp | grep -E \"gcc|make|configure|ld\" | grep -v \"127.0.0.1\"'"
        tmux split-window -v -p 50 "watch -n 2 'echo \"ENTROPY: \$(cat /proc/sys/kernel/random/entropy_avail)\"; iostat -dx 1 2 | awk \"/avg-cpu/ {getline; print \\\$4 \\\"% iowait\\\"}\"'"
        tmux select-pane -t 0
        echo ">> BTC Dashboard Synchronized..."
    fi
}

# --- 9. PERSISTENCE BRIDGE (PACKAGING) ---
function f_package() {
    local PKG_NAME="dcosnet-baseline-${SYS_LABEL}-${v_linux}.tar.xz"
    local PKG_PATH="${BTC_ARCHIVE}/completed"
    mkdir -p "${PKG_PATH}"
    
    echo ">> [AGPL-EXPORT] Compressing Forge State to Archive..."
    # Section 13 Note: This archive constitutes part of the "Corresponding Source"
    tar -cJpf "${PKG_PATH}/${PKG_NAME}" -C "${NEWROOT}" .
    
    local pkg_hash=$(sha256sum "${PKG_PATH}/${PKG_NAME}" | awk '{print $1}')
    setfattr -n user.btc.pkg_hash -v "${pkg_hash}" "${PKG_PATH}/${PKG_NAME}"
    
    # Preserve forensic logs for the LeadNode database
    mkdir -p "${BTC_ARCHIVE}/logs"
    cp -rv "${LOGS}" "${BTC_ARCHIVE}/logs/${SYS_LABEL}_$(date +%Y%m%d)"
    echo ">> [SUCCESS] Artifact preserved at ${PKG_PATH}/${PKG_NAME}"
}

function f_set_exports() {
    # Pivot build tools to the DCOSNET sovereign toolchain
    export CC="ccache ${NEWROOT}/bin/${TARGET}-gcc-${SYS_LABEL}"
    export CXX="ccache ${NEWROOT}/bin/${TARGET}-g++-${SYS_LABEL}"
    export AR="${NEWROOT}/bin/${TARGET}-gcc-ar-${SYS_LABEL}"
    export NM="${NEWROOT}/bin/${TARGET}-gcc-nm-${SYS_LABEL}"
    export RANLIB="${NEWROOT}/bin/${TARGET}-gcc-ranlib-${SYS_LABEL}"
    export CFLAGS="${GLOBAL_CFLAGS}"
    export CXXFLAGS="${GLOBAL_CFLAGS}"
    export LDFLAGS="${GLOBAL_LDFLAGS}"
}

# --- 10. CORE BUILD STAGES ---
function f_binutils() {
    cd ${SOURCES_ACTIVE}
    tar -axf ${SOURCE_CACHE}/${v_binutils}*
    cd binutils-* && mkdir -p build && cd build
    f_exec_log "../configure --prefix=${NEWROOT} --target=${TARGET} --with-sysroot=${NEWROOT} --program-suffix=-${SYS_LABEL} --disable-nls --disable-multilib" "binutils-conf"
    f_exec_log "make ${v_threads}" "binutils-make"
    f_exec_log "make install" "binutils-install" "install"
}

function f_kernel_headers() {
    cd ${SOURCES_ACTIVE}
    tar -axf ${SOURCE_CACHE}/${v_linux}*
    cd linux-*
    f_exec_log "make mrproper && make headers" "kernel-headers"
    cp -rv usr/include/* ${NEWROOT}/include
}

function f_gcc_p1() {
    cd ${SOURCES_ACTIVE}
    tar -axf ${SOURCE_CACHE}/${v_gcc}*
    cd gcc-*
    for lib in gmp mpfr mpc; do tar -xf ${SOURCE_CACHE}/${lib}*; mv -v ${lib}-* ${lib}; done
    mkdir -p build && cd build
    f_exec_log "../configure --target=${TARGET} --prefix=${NEWROOT} --with-sysroot=${NEWROOT} --program-suffix=-${SYS_LABEL} --without-headers --disable-shared --disable-threads --enable-languages=c,c++" "gcc1-conf"
    f_exec_log "make ${v_threads}" "gcc1-make"
    f_exec_log "make install" "gcc1-install" "install"
}

function f_glibc() {
    f_set_exports
    cd ${SOURCES_ACTIVE}/glibc-*
    mkdir -p build && cd build
    f_exec_log "../configure --prefix=${NEWROOT} --host=${TARGET} --with-headers=${NEWROOT}/include libc_cv_slibdir=${NEWROOT}/lib" "glibc-conf"
    f_exec_log "make ${v_threads}" "glibc-make"
    f_exec_log "make DESTDIR=${NEWROOT} install" "glibc-install" "install"
}

function f_gcc_p2() {
    f_set_exports
    cd ${SOURCES_ACTIVE}/gcc-*/build && rm -rf *
    f_exec_log "../configure --prefix=${NEWROOT} --target=${TARGET} --program-suffix=-${SYS_LABEL} --enable-languages=c,c++ --with-build-sysroot=${NEWROOT}" "gcc2-conf"
    f_exec_log "make ${v_threads}" "gcc2-make"
    f_exec_log "make install" "gcc2-install" "install"
}

function f_kernel_binary() {
    f_set_exports
    cd ${SOURCES_ACTIVE}/linux-*
    echo "-dcosnet-${SYS_LABEL}" > .scmversion
    f_exec_log "make ${v_threads} LOCALVERSION=-dcosnet-${SYS_LABEL} bzImage" "kernel-bin-make"
    cp -v arch/x86/boot/bzImage ${NEWROOT}/boot/vmlinuz-${v_linux}-${SYS_LABEL}-dcosnet
}

# --- 11. DEPLOYMENT & BOOT CONFIGURATION ---
function f_install_target() {
    local TARGET_PART="${1}"
    local MNT_POINT="/mnt/btc_target"
    mkdir -p ${MNT_POINT} && mount ${TARGET_PART} ${MNT_POINT}
    
    local DISTRO="Generic-Source"
    [[ -f "${MNT_POINT}/etc/lunar/version" ]] && DISTRO="Lunar"
    [[ -f "${MNT_POINT}/etc/sorcery/version" ]] && DISTRO="SourceMage"
    [[ -f "${MNT_POINT}/etc/openwrt_version" ]] && DISTRO="OpenWrt"
    [[ -d "${MNT_POINT}/etc/portage" ]] && DISTRO="Gentoo"
    [[ -f "${MNT_POINT}/etc/exherbo-release" ]] && DISTRO="Exherbo"
    [[ -f "${MNT_POINT}/etc/cruxversion" ]] && DISTRO="CRUX"

    echo ">> [DCOSNET SWARM] Deploying Silicon-Identity to Dell Optiplex 3050 Micro Variants / ${DISTRO} target..."
    
    # Kernel Handoff
    mkdir -p ${MNT_POINT}/boot
    cp -v ${NEWROOT}/boot/vmlinuz-* ${MNT_POINT}/boot/
    
    # Binary Sync with safe-links
    local bin_dest="/usr/local/bin"
    [[ "$DISTRO" == "OpenWrt" ]] && bin_dest="/usr/bin"
    
    f_exec_log "rsync -avzX --safe-links ${NEWROOT}/bin/ ${MNT_POINT}${bin_dest}/" "${DISTRO}_deploy" "install"
    umount ${MNT_POINT}
    echo ">> [SUCCESS] Swarm Node Seeded: ${DISTRO}"
}

function f_boot_deploy() {
    local TYPE="${1:-grub2-legacy-style}"
    local TARGET_PART="${2:-/dev/sda3}"
    local KERNEL_IMG="vmlinuz-${v_linux}-${SYS_LABEL}-dcosnet"
    
    echo ">> BTC-0.2.0: Deploying ${TYPE} config..."

    case ${TYPE} in
        grub1)
            cat <<EOF > /boot/grub/menu.lst
title BTC SourceMage [${SYS_LABEL}]
    root (hd0,2)
    kernel /boot/${KERNEL_IMG} root=${TARGET_PART} rw quiet
EOF
            ;;
        lilo)
            cat <<EOF > /etc/lilo.conf
boot=/dev/sda
image=/boot/${KERNEL_IMG}
    label=BTC-SM
    root=${TARGET_PART}
    read-only
EOF
            /sbin/lilo
            ;;
        grub2-legacy-style)
            cat <<EOF > /etc/grub.d/40_custom
#!/bin/sh
exec tail -n +3 \$0
menuentry 'SourceMage [Silicon: ${SYS_LABEL}]' {
    set root='(hd0,gpt3)'
    linux /boot/${KERNEL_IMG} root=${TARGET_PART} rw quiet
}
EOF
            grub-mkconfig -o /boot/grub/grub.cfg
            ;;
        syslinux)
            cat <<EOF > /boot/syslinux/syslinux.cfg
LABEL btc
    LINUX ../${KERNEL_IMG}
    APPEND root=${TARGET_PART} rw
EOF
            ;;
    esac
}

# --- 12. MAIN ORCHESTRATION ---
function f_main() {
    [[ $EUID -ne 0 ]] && { echo ">> Root Required."; exit 1; }
    local TARGET_DEV="${1:-}" 

    f_agpl_header # Display license status to all interacting users
    f_silicon_probe
    f_setup
    
    # Forge Pipeline
    f_binutils
    f_kernel_headers
    f_gcc_p1
    f_glibc
    f_gcc_p2
    f_kernel_binary
    
    # 1. Mandatory Persistence (Archive)
    f_package 
    
    # 2. Optional Physical Seed & Boot deployment
    if [[ -n "${TARGET_DEV}" ]]; then
        f_install_target "${TARGET_DEV}"
        f_boot_deploy "grub2-legacy-style" "${TARGET_DEV}"
    fi

    # 3. Final Zero-Footprint Cleanup: Unmount ramfs
    cd / && umount -l ${SOURCES_ACTIVE}
    echo ">> [SUCCESS] BTC-0.2.0-AGPL: Sovereign Forge Complete."
}

# One-Shot Execution
f_main "$@"