usm/installer/pm_pacman.sh

#!/bin/bash
# pm_pacman.sh - pacman package manager implementation for Arch systems
#
# To add a new package manager, create a file named pm_<name>.sh with:
#  - pm_<name>_detect: Returns 0 if this PM is available, 1 otherwise
#  - pm_<name>_get_missing_deps: Prints space-separated list of missing packages
#  - pm_<name>_install_missing_deps: Installs the missing packages
#
# Arch notes:
#  - PACMAN_DEPS mirror the dnf/apt dependency sets. Arch carries no
#    -dev split: glib2, json-glib, libgee, gobject-introspection ship
#    headers, pkg-config, .gir/.typelib and .vapi artifacts themselves,
#    and glibc already bundles the crt objects gcc needs, so no
#    companion package (musl-dev style) is required.

# Package names required by USM
PACMAN_DEPS="vala meson ninja pkgconf gcc glib2 libsodium json-glib libarchive libgee xz gobject-introspection"

# Check if this package manager is available
pm_pacman_detect() {
    command -v pacman &>/dev/null
}

# Get list of missing dependencies
pm_pacman_get_missing_deps() {
    local -a missing=()

    for pkg in $PACMAN_DEPS; do
        if ! pacman -Q "$pkg" &>/dev/null; then
            missing+=("$pkg")
        fi
    done

    echo "${missing[*]}"
}

# Install missing dependencies
pm_pacman_install_missing_deps() {
    local missing=$(pm_pacman_get_missing_deps)

    if [[ -z "$missing" ]]; then
        log_info "All dependencies are already installed"
        return 0
    fi

    log_step "Installing packages via pacman: ${missing}"

    local sudo=""
    if ! is_root; then
        sudo=$(get_sudo)
    fi

    local pacman_opts="--needed --noconfirm"

    if [[ -n "$sudo" ]]; then
        $sudo pacman -Sy $pacman_opts $missing
    else
        pacman -Sy $pacman_opts $missing
    fi
}