#!/bin/bash
# ProxMenux - Coral TPU Installer (unified: PCIe/M.2 + USB)
# =========================================================
# Author      : MacRimi
# License     : MIT
# Version     : 2.0 (unified PCIe+USB; auto-detect; feranick fork; libedgetpu runtime)
# Last Updated: 17/04/2026
# =========================================================
#
# One entry point for every Coral variant. At startup the script detects
# what Coral hardware is present on the host and installs only what is
# actually needed:
#
#   • Coral M.2 / Mini-PCIe (vendor 1ac1 on PCIe)
#       → build and install `gasket` + `apex` kernel modules via DKMS
#         (feranick/gasket-driver fork; google as fallback with patches)
#       → create apex group + udev rules
#       → reboot required to load the fresh kernel module
#
#   • Coral USB Accelerator (USB IDs 1a6e:089a / 18d1:9302)
#       → add the Google Coral APT repository (signed-by keyring)
#       → install libedgetpu1-std (Edge TPU runtime)
#       → udev rules come with the package
#       → no reboot required
#
#   • Both present → both paths are run in sequence
#   • Neither present → informative dialog and clean exit
#
# The script is idempotent: reruns on already-configured hosts skip work
# that is already done and recover from broken gasket-dkms package state
# (typical after a kernel upgrade on PVE 9).

# Guarantee a valid working directory before anything else. When the user
# re-runs the installer from a previous /tmp/gasket-driver/... path that our
# own `rm -rf gasket-driver` removed, the inherited cwd is orphaned and bash
# emits `chdir: error retrieving current directory` warnings from every
# subprocess. Moving to / at launch makes the rest of the script immune to
# that state.
cd / 2>/dev/null || true

LOCAL_SCRIPTS="/usr/local/share/proxmenux/scripts"
BASE_DIR="/usr/local/share/proxmenux"
UTILS_FILE="$BASE_DIR/utils.sh"
LOG_FILE="/tmp/coral_install.log"

# Hardware detection results, set by detect_coral_hardware().
CORAL_PCIE_COUNT=0
CORAL_USB_COUNT=0

if [[ -f "$UTILS_FILE" ]]; then
  source "$UTILS_FILE"
fi

load_language
initialize_cache


# ============================================================
# Hardware detection
# ============================================================
detect_coral_hardware() {
  CORAL_PCIE_COUNT=0
  CORAL_USB_COUNT=0

  # PCIe / M.2 / Mini-PCIe — vendor 0x1ac1 (Global Unichip Corp.)
  if [[ -d /sys/bus/pci/devices ]]; then
    for dev in /sys/bus/pci/devices/*; do
      [[ -e "$dev/vendor" ]] || continue
      local vendor
      vendor=$(cat "$dev/vendor" 2>/dev/null)
      if [[ "$vendor" == "0x1ac1" ]]; then
        CORAL_PCIE_COUNT=$((CORAL_PCIE_COUNT + 1))
      fi
    done
  fi

  # USB Accelerator
  #   1a6e:089a  Global Unichip Corp. (unprogrammed state — before runtime loads fw)
  #   18d1:9302  Google Inc.          (programmed state   — after runtime talks to it)
  if command -v lsusb >/dev/null 2>&1; then
    CORAL_USB_COUNT=$(lsusb 2>/dev/null \
      | grep -cE 'ID (1a6e:089a|18d1:9302)' || true)
  fi
}


# ============================================================
# Dialogs
# ============================================================
no_hardware_dialog() {
  dialog --backtitle "ProxMenux" \
    --title "$(translate 'No Coral Detected')" \
    --msgbox "\n$(translate 'No Coral TPU device was found on this host (neither PCIe/M.2 nor USB).')\n\n$(translate 'Connect a Coral Accelerator and try again.')" \
    12 72
}

pre_install_prompt() {
  local msg="\n"
  msg+="$(translate 'Detected Coral hardware:')\n\n"
  msg+="  • $(translate 'M.2 / PCIe devices:') ${CORAL_PCIE_COUNT}\n"
  msg+="  • $(translate 'USB Accelerators:')   ${CORAL_USB_COUNT}\n\n"

  msg+="$(translate 'This installer will:')\n"
  if [[ "$CORAL_PCIE_COUNT" -gt 0 ]]; then
    msg+="  • $(translate 'Build and install the gasket and apex kernel modules (DKMS)')\n"
    msg+="  • $(translate 'Set up the apex group and udev rules')\n"
  fi
  if [[ "$CORAL_USB_COUNT" -gt 0 ]]; then
    msg+="  • $(translate 'Configure the Google Coral APT repository')\n"
    msg+="  • $(translate 'Install the Edge TPU runtime (libedgetpu1-std)')\n"
  fi

  if [[ "$CORAL_PCIE_COUNT" -gt 0 ]]; then
    msg+="\n$(translate 'A reboot is required after installation to load the new kernel modules.')"
  fi

  msg+="\n\n$(translate 'Do you want to proceed?')"

  if ! dialog --backtitle "ProxMenux" \
      --title "$(translate 'Coral TPU Installation')" \
      --yesno "$msg" 20 78; then
    exit 0
  fi
}


# ============================================================
# PCIe / M.2 branch — gasket + apex kernel modules via DKMS
# ============================================================

ensure_apex_group_and_udev() {
  msg_info "$(translate 'Ensuring apex group and udev rules...')"

  if ! getent group apex >/dev/null; then
    groupadd --system apex || true
    msg_ok "$(translate 'System group apex created.')"
  else
    msg_ok "$(translate 'System group apex already exists.')"
  fi

  cat >/etc/udev/rules.d/99-coral-apex.rules <<'EOF'
# Coral / Google APEX TPU (M.2 / PCIe)
# Assign group "apex" and safe permissions to device nodes
KERNEL=="apex_*", GROUP="apex", MODE="0660"
SUBSYSTEM=="apex", GROUP="apex", MODE="0660"
EOF

  if [[ -f /usr/lib/udev/rules.d/60-gasket-dkms.rules ]]; then
    sed -i 's/GROUP="[^"]*"/GROUP="apex"/g' /usr/lib/udev/rules.d/60-gasket-dkms.rules || true
  fi

  udevadm control --reload-rules
  udevadm trigger --subsystem-match=apex || true

  msg_ok "$(translate 'apex group and udev rules are in place.')"

  if ls -l /dev/apex_* 2>/dev/null | grep -q ' apex '; then
    msg_ok "$(translate 'Coral TPU device nodes detected with correct group (apex).')"
  else
    msg_warn "$(translate 'apex device node not found yet; a reboot may be required.')"
  fi
}

cleanup_broken_gasket_dkms() {
  # Recover from a broken gasket-dkms .deb state (half-configured, unpacked,
  # half-installed). This is a common failure mode on PVE 9 kernel upgrades:
  # dkms autoinstall tries to rebuild against the new kernel, fails, and
  # leaves dpkg stuck — which in turn blocks every subsequent apt-get call.
  local pkg_state
  pkg_state=$(dpkg -l gasket-dkms 2>/dev/null | awk '/^[a-zA-Z][a-zA-Z]/ {print $1}' | tail -1)

  [[ -z "$pkg_state" ]] && return 0  # package not present — nothing to clean

  case "$pkg_state" in
    ii|rc)
      msg_info "$(translate 'Removing any pre-existing gasket-dkms package...')"
      dpkg -r gasket-dkms >>"$LOG_FILE" 2>&1 || true
      dkms remove gasket/1.0 --all >>"$LOG_FILE" 2>&1 || true
      msg_ok "$(translate 'Pre-existing gasket-dkms package removed.')"
      ;;
    *)
      msg_warn "$(translate 'Detected broken gasket-dkms package state:') ${pkg_state}. $(translate 'Forcing removal...')"
      dpkg --remove --force-remove-reinstreq gasket-dkms >>"$LOG_FILE" 2>&1 || true
      dpkg --purge --force-all gasket-dkms >>"$LOG_FILE" 2>&1 || true
      dkms remove gasket/1.0 --all >>"$LOG_FILE" 2>&1 || true
      apt-get install -f -y >>"$LOG_FILE" 2>&1 || true
      msg_ok "$(translate 'Broken gasket-dkms package state recovered.')"
      ;;
  esac
}

clone_gasket_sources() {
  # Primary:  feranick/gasket-driver  — community fork, actively maintained,
  #                                     carries patches for kernel 6.10/6.12/6.13.
  # Fallback: google/gasket-driver    — upstream, stale. Requires manual patches.
  # Sets GASKET_SOURCE_USED so the patch step knows whether to apply them.
  local FERANICK_URL="https://github.com/feranick/gasket-driver.git"
  local GOOGLE_URL="https://github.com/google/gasket-driver.git"

  cd /tmp || exit 1
  rm -rf gasket-driver >>"$LOG_FILE" 2>&1

  msg_info "$(translate 'Cloning Coral driver repository (feranick fork)...')"
  if git clone --depth=1 "$FERANICK_URL" gasket-driver >>"$LOG_FILE" 2>&1; then
    GASKET_SOURCE_USED="feranick"
    msg_ok "$(translate 'feranick/gasket-driver cloned (actively maintained, kernel 6.12+ ready).')"
    return 0
  fi

  msg_warn "$(translate 'feranick fork unreachable. Falling back to google/gasket-driver...')"
  rm -rf gasket-driver >>"$LOG_FILE" 2>&1
  if git clone --depth=1 "$GOOGLE_URL" gasket-driver >>"$LOG_FILE" 2>&1; then
    GASKET_SOURCE_USED="google"
    msg_ok "$(translate 'google/gasket-driver cloned (fallback — will apply local patches).')"
    return 0
  fi

  msg_error "$(translate 'Could not clone any gasket-driver repository. Check your internet connection and') ${LOG_FILE}"
  exit 1
}

show_dkms_build_failure() {
  # Print the last 50 lines of make.log on-screen so the user sees the real
  # compilation error without having to dig the log file.
  local make_log="/var/lib/dkms/gasket/1.0/build/make.log"
  echo "" >&2
  msg_warn "$(translate 'DKMS build failed. Last lines of make.log:')"
  if [[ -f "$make_log" ]]; then
    {
      echo "---- /var/lib/dkms/gasket/1.0/build/make.log ----"
      cat "$make_log"
    } >>"$LOG_FILE" 2>&1
    tail -n 50 "$make_log" >&2
  else
    echo "$(translate '(make.log not found — DKMS may have failed before invoking make)')" >&2
  fi
  echo "" >&2
  echo -e "${TAB}${BL}$(translate 'Full log:')${CL} ${LOG_FILE}" >&2
  echo "" >&2
}

install_gasket_apex_dkms() {
  # Detect running kernel — used both to pull matching headers and to apply
  # kernel-version-specific patches if we fall back to google/gasket-driver.
  local KVER KMAJ KMIN
  KVER=$(uname -r)
  KMAJ=$(echo "$KVER" | cut -d. -f1)
  KMIN=$(echo "$KVER" | cut -d. -f2 | cut -d+ -f1 | cut -d- -f1)

  cleanup_broken_gasket_dkms

  msg_info "$(translate 'Installing build dependencies...')"
  apt-get update -qq >>"$LOG_FILE" 2>&1
  if ! apt-get install -y git dkms build-essential "proxmox-headers-${KVER}" >>"$LOG_FILE" 2>&1; then
    msg_error "$(translate 'Error installing build dependencies. Check') ${LOG_FILE}"
    exit 1
  fi
  msg_ok "$(translate 'Build dependencies installed.')"

  clone_gasket_sources

  cd /tmp/gasket-driver || exit 1

  # Patches are only needed for the stale google fork. feranick already carries
  # the equivalent fixes upstream; re-applying them would double-edit sources.
  if [[ "$GASKET_SOURCE_USED" == "google" ]]; then
    msg_info "$(translate 'Patching source for kernel compatibility...')"

    # no_llseek was removed in kernel 6.5 — replace with noop_llseek
    if [[ "$KMAJ" -gt 6 ]] || [[ "$KMAJ" -eq 6 && "$KMIN" -ge 5 ]]; then
      sed -i 's/\.llseek = no_llseek/\.llseek = noop_llseek/' src/gasket_core.c
    fi

    # MODULE_IMPORT_NS syntax changed to string-literal in 6.13.
    # Applying this patch on kernel <6.13 causes a compile error.
    if [[ "$KMAJ" -gt 6 ]] || [[ "$KMAJ" -eq 6 && "$KMIN" -ge 13 ]]; then
      sed -i 's/^MODULE_IMPORT_NS(DMA_BUF);/MODULE_IMPORT_NS("DMA_BUF");/' src/gasket_page_table.c
    fi

    msg_ok "$(translate 'Source patched successfully.') (kernel ${KVER})"
  else
    msg_info2 "$(translate 'Skipping manual patches — feranick fork already supports this kernel.')"
  fi

  local GASKET_SRC="/usr/src/gasket-1.0"

  if [[ ! -d /tmp/gasket-driver/src ]]; then
    msg_error "$(translate 'Expected /tmp/gasket-driver/src not found. The clone seems incomplete or uses an unknown layout.')"
    { echo "---- /tmp/gasket-driver/ contents ----"; ls -la /tmp/gasket-driver 2>/dev/null || true; } >>"$LOG_FILE"
    exit 1
  fi
  if [[ ! -f /tmp/gasket-driver/src/Makefile ]]; then
    msg_error "$(translate 'Expected Makefile not found in /tmp/gasket-driver/src. Source tree is incomplete.')"
    exit 1
  fi

  msg_info "$(translate 'Removing previous DKMS source tree...')"
  dkms remove gasket/1.0 --all >>"$LOG_FILE" 2>&1 || true
  if [[ -d "$GASKET_SRC" ]]; then
    if ! rm -rf "$GASKET_SRC" 2>>"$LOG_FILE"; then
      msg_error "$(translate 'Could not remove previous DKMS tree at') ${GASKET_SRC}. $(translate 'Check') ${LOG_FILE}"
      exit 1
    fi
  fi
  msg_ok "$(translate 'Previous DKMS tree cleared.')"

  # Copy only the `src/` contents (where the kernel sources live) so
  # Makefile + *.c + *.h sit at the DKMS tree root, matching the Debian
  # packaging layout (`dh_install src/* usr/src/gasket-$(VERSION)/`).
  msg_info "$(translate 'Copying sources to') ${GASKET_SRC}..."
  mkdir -p "$GASKET_SRC"
  if ! cp -a /tmp/gasket-driver/src/. "${GASKET_SRC}/" 2>>"$LOG_FILE"; then
    msg_error "$(translate 'Failed to copy sources into') ${GASKET_SRC}. $(translate 'Check') ${LOG_FILE}"
    exit 1
  fi
  if [[ ! -f "$GASKET_SRC/Makefile" ]]; then
    msg_error "$(translate 'Makefile missing in') ${GASKET_SRC} $(translate 'after copy; source tree is incomplete.')"
    exit 1
  fi
  msg_ok "$(translate 'Sources copied to') ${GASKET_SRC}"

  # The repo ships debian/gasket-dkms.dkms as a template with a
  # #MODULE_VERSION# placeholder that the .deb pipeline substitutes. Since we
  # install directly from sources (no .deb), we write our own dkms.conf.
  # MAKE[0] passes ${kernelver} to the Makefile so multi-kernel rebuilds
  # (PVE's autoinstall on new kernel installs) target the right headers.
  msg_info "$(translate 'Generating dkms.conf...')"
  cat > "$GASKET_SRC/dkms.conf" <<'EOF'
PACKAGE_NAME="gasket"
PACKAGE_VERSION="1.0"
BUILT_MODULE_NAME[0]="gasket"
BUILT_MODULE_NAME[1]="apex"
DEST_MODULE_LOCATION[0]="/updates/dkms"
DEST_MODULE_LOCATION[1]="/updates/dkms"
MAKE[0]="make KVERSION=${kernelver}"
CLEAN="make clean"
AUTOINSTALL="yes"
EOF
  if [[ ! -s "$GASKET_SRC/dkms.conf" ]]; then
    msg_error "$(translate 'Failed to write') ${GASKET_SRC}/dkms.conf"
    exit 1
  fi
  msg_ok "$(translate 'dkms.conf generated.')"

  msg_info "$(translate 'Registering module with DKMS...')"
  if ! dkms add "$GASKET_SRC" >>"$LOG_FILE" 2>&1; then
    msg_error "$(translate 'DKMS add failed. Check') ${LOG_FILE}"
    exit 1
  fi
  msg_ok "$(translate 'DKMS module registered.')"

  msg_info "$(translate 'Compiling Coral TPU drivers for current kernel...')"
  if ! dkms build gasket/1.0 -k "$KVER" >>"$LOG_FILE" 2>&1; then
    show_dkms_build_failure
    msg_error "$(translate 'DKMS build failed.')"
    exit 1
  fi
  if ! dkms install gasket/1.0 -k "$KVER" >>"$LOG_FILE" 2>&1; then
    show_dkms_build_failure
    msg_error "$(translate 'DKMS install failed.')"
    exit 1
  fi
  msg_ok "$(translate 'Drivers compiled and installed via DKMS.') (source: ${GASKET_SOURCE_USED})"

  ensure_apex_group_and_udev

  msg_info "$(translate 'Loading modules...')"
  modprobe gasket >>"$LOG_FILE" 2>&1 || true
  modprobe apex   >>"$LOG_FILE" 2>&1 || true
  if lsmod | grep -q '\bapex\b'; then
    msg_ok "$(translate 'Modules loaded.')"
  else
    msg_warn "$(translate 'Installation finished but drivers are not loaded. A reboot may be required.')"
  fi

  echo "---- dmesg | grep -i apex (last lines) ----" >>"$LOG_FILE"
  dmesg | grep -i apex | tail -n 20 >>"$LOG_FILE" 2>&1
}


# ============================================================
# USB branch — libedgetpu runtime from Google's APT repository
# ============================================================

install_libedgetpu_runtime() {
  local KEYRING=/etc/apt/keyrings/coral-edgetpu.gpg
  local LIST_FILE=/etc/apt/sources.list.d/coral-edgetpu.list

  # Modern repo configuration: one keyring file under /etc/apt/keyrings plus
  # a sources.list.d entry with `signed-by=`. Avoids the deprecated apt-key.
  msg_info "$(translate 'Setting up the Google Coral APT repository...')"
  mkdir -p /etc/apt/keyrings

  if [[ ! -s "$KEYRING" ]]; then
    if ! curl -fsSL https://packages.cloud.google.com/apt/doc/apt-key.gpg \
        | gpg --dearmor -o "$KEYRING" 2>>"$LOG_FILE"; then
      msg_error "$(translate 'Failed to fetch the Google Coral GPG key. Check') ${LOG_FILE}"
      exit 1
    fi
    chmod 0644 "$KEYRING"
  fi

  cat > "$LIST_FILE" <<EOF
deb [signed-by=${KEYRING}] https://packages.cloud.google.com/apt coral-edgetpu-stable main
EOF

  if ! apt-get update -qq >>"$LOG_FILE" 2>&1; then
    msg_warn "$(translate 'apt-get update returned warnings. Continuing anyway; check') ${LOG_FILE}"
  fi
  msg_ok "$(translate 'Coral APT repository ready.')"

  # libedgetpu1-std = standard performance; libedgetpu1-max = overclocked mode
  # (more heat). We default to -std; users who explicitly want -max can install
  # it manually. Either way the udev rules come with the package.
  msg_info "$(translate 'Installing Edge TPU runtime (libedgetpu1-std)...')"
  if ! apt-get install -y libedgetpu1-std >>"$LOG_FILE" 2>&1; then
    msg_error "$(translate 'Failed to install libedgetpu1-std. Check') ${LOG_FILE}"
    exit 1
  fi
  msg_ok "$(translate 'Edge TPU runtime installed.')"

  # Reload udev so the rules shipped with libedgetpu1-std apply to any USB
  # Coral already plugged in (otherwise they would only apply after replug).
  udevadm control --reload-rules >/dev/null 2>&1 || true
  udevadm trigger --subsystem-match=usb >/dev/null 2>&1 || true
}


# ============================================================
# Final prompt
# ============================================================
restart_prompt() {
  if whiptail --title "$(translate 'Coral TPU Installation')" --yesno \
      "$(translate 'The installation requires a server restart to apply changes. Do you want to restart now?')" 10 70; then
    msg_warn "$(translate 'Restarting the server...')"
    reboot
  else
    msg_success "$(translate 'Completed. Press Enter to return to menu...')"
    read -r
  fi
}


# ============================================================
# Main orchestrator
# ============================================================
main() {
  : >"$LOG_FILE"

  detect_coral_hardware

  # Nothing plugged in — nothing to do.
  if [[ "$CORAL_PCIE_COUNT" -eq 0 && "$CORAL_USB_COUNT" -eq 0 ]]; then
    no_hardware_dialog
    exit 0
  fi

  pre_install_prompt

  show_proxmenux_logo
  msg_title "$(translate 'Coral TPU Installation')"

  # Force non-interactive apt/dpkg for the whole run so cleanup_broken_gasket_dkms
  # and the two install paths never get blocked by package-maintainer prompts.
  export DEBIAN_FRONTEND=noninteractive

  # Branch 1 — PCIe / M.2 (kernel modules). Runs first so the reboot reminder
  # at the end only appears when we actually touched kernel modules.
  if [[ "$CORAL_PCIE_COUNT" -gt 0 ]]; then
    msg_info2 "$(translate 'Coral M.2 / PCIe detected — installing gasket and apex kernel modules...')"
    install_gasket_apex_dkms
  fi

  # Branch 2 — USB (user-space runtime).
  if [[ "$CORAL_USB_COUNT" -gt 0 ]]; then
    msg_info2 "$(translate 'Coral USB Accelerator detected — installing Edge TPU runtime...')"
    install_libedgetpu_runtime
  fi

  echo
  if [[ "$CORAL_PCIE_COUNT" -gt 0 ]]; then
    msg_success "$(translate 'Coral TPU drivers installed and loaded successfully.')"
    restart_prompt
  else
    # USB-only install. No reboot required; the udev rules and runtime are
    # already active. Ready to passthrough the device to an LXC/VM.
    msg_success "$(translate 'Coral USB runtime installed. No reboot required.')"
    msg_success "$(translate 'Completed. Press Enter to return to menu...')"
    read -r
  fi
}

main