#!/bin/bash

# Function to check if a package is installed
is_installed() {
  pacman -Qi "$1" &> /dev/null
}

# Function to check if a package is installed
is_group_installed() {
  pacman -Qg "$1" &> /dev/null
}

# Function to install packages if not already installed
install_packages() {
  local packages=("$@")
  local to_install=()

  for pkg in "${packages[@]}"; do
    if ! is_installed "$pkg" && ! is_group_installed "$pkg"; then
      to_install+=("$pkg")
    fi
  done

  if [ ${#to_install[@]} -ne 0 ]; then
    echo "Installing: ${to_install[*]}"
    yay -S --noconfirm --answerdiff=None --answeredit=None --answerclean=None "${to_install[@]}"
  fi
}

# Function to install pipx applications if not already installed
install_pipx_apps() {
  local installed app status=0
  installed="$(pipx list --short 2> /dev/null | cut -d' ' -f1)"

  for app in "$@"; do
    if ! grep -qx "$app" <<< "$installed"; then
      echo "Installing $app with pipx..."
      pipx install "$app" || status=1
    fi
  done
  return $status
}

# Reinstall gext if missing or broken. Its pipx venv goes stale when Arch
# upgrades Python, and migrations run before updates.d/60-pipx.sh rebuilds it.
ensure_gext() {
  ~/.local/bin/gext --version &> /dev/null && return 0
  echo "gext missing or broken, reinstalling..."
  pipx uninstall gnome-extensions-cli &> /dev/null || true
  pipx install --python "$(which python3)" gnome-extensions-cli --system-site-packages
}

# Function to remove pacman/AUR packages if installed
remove_packages() {
  local packages=("$@")
  local to_remove=()

  for pkg in "${packages[@]}"; do
    if is_installed "$pkg"; then
      to_remove+=("$pkg")
    fi
  done

  if [ ${#to_remove[@]} -ne 0 ]; then
    echo "Removing: ${to_remove[*]}"
    sudo pacman -Rns --noconfirm "${to_remove[@]}"
  fi
}

# Function to remove flatpak applications if installed
remove_flatpaks() {
  local flatpaks=("$@")
  local to_remove=()

  for pak in "${flatpaks[@]}"; do
    if flatpak list --system | grep -qi "$pak"; then
      to_remove+=("$pak")
    fi
  done

  if [ ${#to_remove[@]} -ne 0 ]; then
    echo "Removing flatpaks: ${to_remove[*]}"
    sudo flatpak uninstall --system --noninteractive "${to_remove[@]}"
  fi
}

# Function to enable systemd services if not already enabled
enable_services() {
  for service in "$@"; do
    if ! systemctl is-enabled "$service" &> /dev/null; then
      echo "Enabling $service..."
      sudo systemctl enable "$service"
    else
      echo "$service is already enabled."
    fi
  done
}

# Run each script in migrations/ that hasn't run on this machine yet, oldest
# first. A migration is recorded as done only when it succeeds, and the first
# failure stops the run so a later migration never runs ahead of an earlier one.
run_migrations() {
  local dir="${COREDESKTOP:-$HOME/.local/share/coredesktop}/migrations"
  local state="$HOME/.local/state/coredesktop/migrations"
  local file name

  mkdir -p "$state"
  for file in "$dir"/*.sh; do
    [ -f "$file" ] || continue
    name="$(basename "$file")"
    [ -f "$state/$name" ] && continue

    echo "Running migration $name..."
    if ! bash "$file"; then
      echo "Migration $name failed; it will run again on the next update."
      return 1
    fi
    touch "$state/$name"
  done
}

# Output of the last update's pacman -Su, written by updates.d/10-pacman.sh
PACMAN_UPDATE_LOG="$HOME/.local/state/coredesktop/pacman-update.log"

# True if the last update rebuilt the initramfs and mkinitcpio reported a
# failure. Rebooting then can leave the machine unbootable.
initramfs_build_failed() {
  [ -f "$PACMAN_UPDATE_LOG" ] || return 1
  grep -q "Updating linux initcpios" "$PACMAN_UPDATE_LOG" || return 1
  grep -q "==> ERROR" "$PACMAN_UPDATE_LOG" && return 0

  # Every image built must report success. Older mkinitcpio says "==> Image
  # generation successful", newer says "==> Initcpio image generation successful".
  local built succeeded
  built="$(grep -c "==> Building image from preset" "$PACMAN_UPDATE_LOG")"
  succeeded="$(grep -cE "==> (Initcpio i|I)mage generation successful" "$PACMAN_UPDATE_LOG")"
  (( succeeded == 0 || succeeded < built ))
}

# Install a script atomically (copy to a temp file, then rename over the target)
# so a copy of it that is running right now keeps reading the old file
install_script() {
  local tmp
  tmp="$(mktemp "$2.XXXXXX")" && cp "$1" "$tmp" && chmod 755 "$tmp" && mv -f "$tmp" "$2"
}