#!/bin/bash
# ╔══════════════════════════════════════════════════════════════════════════════╗
# ║  setup/modules/core.sh — Core system services enablement                  ║
# ║                                                                              ║
# ║  PURPOSE:                                                                    ║
# ║    Enables the essential systemd services that every installation needs.    ║
# ║    Also deploys the greetd login manager config from the dotfiles repo.    ║
# ║                                                                              ║
# ║  WHEN TO RUN:                                                                ║
# ║    After core-packages.sh — the services must be installed before they can  ║
# ║    be enabled. Called "svc" in the TUI installer's component checklist.    ║
# ║                                                                              ║
# ║  SERVICES ENABLED:                                                           ║
# ║    - NetworkManager: manages wired/wireless network connections              ║
# ║    - cronie:         cron daemon for scheduled tasks                        ║
# ║    - greetd:         minimal display/login manager (uses tuigreet TUI)     ║
# ║    - fail2ban:       bans IPs after repeated failed SSH/auth attempts       ║
# ║    - udisks2:        auto-mounts USB drives and other removable media       ║
# ╚══════════════════════════════════════════════════════════════════════════════╝

set -euo pipefail
# -e: exit immediately on any error (service enable failures abort the script)
# -u: treat unset variables as errors
# -o pipefail: fail if any pipe stage fails

# Load shared logging helpers (log, skip, warn, err functions)
source "$(dirname "${BASH_SOURCE[0]}")/lib/logging.sh"

# ── NetworkManager ─────────────────────────────────────────────────────────────
# WHY: Arch ships with no network daemon enabled by default. NetworkManager is
#      the most user-friendly option — handles DHCP, WiFi, VPN, and has applets.
# NOTE: systemctl enable only marks it to start at boot; it doesn't start it now.
log "Enabling NetworkManager..."
enable_service NetworkManager.service

# ── cronie ────────────────────────────────────────────────────────────────────
# WHY: Provides the system cron daemon. Some tools (backups, vnstat stats,
#      fail2ban cleanup) rely on cron jobs. Arch does not enable it by default.
log "Enabling cronie..."
enable_service cronie.service

# ── greetd / tuigreet ─────────────────────────────────────────────────────────
# WHY: greetd is a minimal, standards-compliant display manager (login screen).
#      We use the tuigreet greeter which is a TUI (text-mode, no GPU needed).
#      It's lighter than GDM/SDDM and works well on TTY in Wayland setups.
#
# HOW: Copy our pre-configured config.toml from the dotfiles repo into /etc/greetd/
#      then enable the service. The config.toml specifies which greeter to run
#      and optionally auto-login settings.
#      -f flag forces overwrite of any existing config.
log "Deploying greetd config..."
# greetd may not be installed yet at this point (the DE module pulls in
# greetd-tuigreet later), so /etc/greetd does not exist and the cp would fail —
# aborting the module under `set -e` before fail2ban/udisks2 get enabled. Create
# the directory first so the config is staged regardless; greetd reads it once
# installed. enable_service is already non-fatal if the unit is absent.
sudo mkdir -p /etc/greetd
sudo cp -f ~/Dotfiles/desktopenvs/hyprland/greetd-tuigreet/config.toml /etc/greetd/config.toml
enable_service greetd.service

# ── fail2ban ──────────────────────────────────────────────────────────────────
# WHY: Protects against brute-force attacks by monitoring log files and
#      temporarily banning IPs that show malicious signs (too many failed logins).
#      Important on any machine with SSH open to the network.
log "Enabling fail2ban..."
enable_service fail2ban.service

# ── udisks2 ───────────────────────────────────────────────────────────────────
# WHY: udisks2 provides automatic mounting of USB drives and other removable
#      media via D-Bus. Required by file managers (Thunar, pcmanfm) and desktop
#      utilities that want to offer "Open when inserted" functionality.
log "Enabling udisks2..."
enable_service udisks2.service

log "Core services enabled."