# ABOUTME: systemd system and user services for the desktop session.
# ABOUTME: Rebuilt from moonarch/defaults/etc/systemd/, whose units use FHS paths.

{ config, pkgs, lib, moonarchPkgs, ... }:

{
  # --- Audio ---
  services.pipewire = {
    enable = true;
    alsa.enable = true;
    alsa.support32Bit = true;
    pulse.enable = true;
    jack.enable = true;
  };

  # --- Hardware ---
  hardware.bluetooth.enable = true;
  services.blueman.enable = true;
  services.udisks2.enable = true;
  services.upower.enable = true;
  services.gvfs.enable = true;
  services.fwupd.enable = true;
  # power-profiles-daemon over auto-cpufreq: on amd-pstate in active mode the
  # platform decides the frequency from the min/max and EPP registers alone, so
  # the governor is the wrong knob. ppd writes EPP and the ACPI platform_profile;
  # where neither exists it falls back to a driver that touches no hardware.
  services.power-profiles-daemon.enable = true;

  # --- Firewall, replaces the ufw calls in post-install.sh ---
  networking.firewall.enable = true;

  # --- Session services ---
  #
  # Rebuilt rather than copied: the upstream units reference /usr/bin/,
  # which does not exist under Nix.

  systemd.user.services.kanshi = {
    description = "Dynamic display configuration";
    partOf = [ "graphical-session.target" ];
    after = [ "graphical-session.target" ];
    wantedBy = [ "graphical-session.target" ];
    # Without a config kanshi exits with a parse error and, with
    # Restart=on-failure, spins. Monitor profiles are per machine.
    unitConfig.ConditionPathExists = "%h/.config/kanshi/config";
    serviceConfig = {
      Type = "simple";
      ExecStart = lib.getExe pkgs.kanshi;
      Restart = "on-failure";
      RestartSec = 3;
    };
  };

  # --- System services from defaults/etc/systemd/system/ ---
  #
  # Rebuilt rather than copied, same reason as the user units: the originals
  # reference /usr/bin.

  systemd.services.moonarch-batsaver = {
    description = "Restore battery conservation mode threshold";
    after = [ "sysinit.target" ];
    wantedBy = [ "multi-user.target" ];
    unitConfig.ConditionPathExists = [
      "/sys/class/power_supply/BAT0/charge_control_end_threshold"
      "/var/lib/moonarch/batsaver-threshold"
    ];
    serviceConfig = {
      Type = "oneshot";
      ExecStart = "${moonarchPkgs.moonarch-scripts}/bin/moonarch-batsaver-restore";
      NoNewPrivileges = true;
      ProtectHome = true;
      PrivateTmp = true;
      ProtectKernelModules = true;
      ProtectControlGroups = true;
      RestrictNamespaces = true;
      RestrictRealtime = true;
      LockPersonality = true;
    };
  };

  systemd.services.moonarch-camera = {
    description = "Switch off all cameras on boot";
    after = [ "sysinit.target" ];
    wantedBy = [ "multi-user.target" ];
    unitConfig.ConditionPathExistsGlob = "/sys/class/video4linux/video*";
    serviceConfig = {
      Type = "oneshot";
      ExecStart = "${moonarchPkgs.moonarch-scripts}/bin/moonarch-camera-boot";
      NoNewPrivileges = true;
      ProtectHome = true;
      PrivateTmp = true;
      ProtectKernelModules = true;
      ProtectControlGroups = true;
      RestrictNamespaces = true;
      RestrictRealtime = true;
      LockPersonality = true;
    };
  };

  # The bar, launcher and every popout. A unit rather than a spawn-at-startup so
  # a crash does not leave the session without a bar until the next login.
  systemd.user.services.quickshell = {
    description = "Quickshell bar and shell";
    partOf = [ "graphical-session.target" ];
    after = [ "graphical-session.target" ];
    wantedBy = [ "graphical-session.target" ];
    # The widgets shell out to niri, nmcli, powerprofilesctl, the moonarch
    # scripts and a dozen more, and which ones is a property of the QML, not of
    # this file. As a spawn-at-startup it inherited the session PATH; the unit
    # gets the same set rather than a list that goes stale on the next widget.
    path = [ config.system.path ];
    serviceConfig = {
      Type = "simple";
      ExecStart = "${lib.getExe pkgs.quickshell} -c moonarch";
      Restart = "on-failure";
      RestartSec = 3;
    };
  };

  # nixpkgs ships the package but no module, and the package carries no unit of
  # its own, so it is declared here. Mirrors /usr/lib/systemd/user/stasis.service.
  systemd.user.services.stasis = {
    description = "Stasis Wayland Idle Manager";
    partOf = [ "graphical-session.target" ];
    after = [ "graphical-session.target" ];
    wantedBy = [ "graphical-session.target" ];
    # Every binary a configured action names has to be listed here. stasis does
    # not run the actions through a login shell, so /etc/profile never applies
    # and nothing resolves via /run/current-system/sw/bin. A missing binary is
    # silent: the spawn fails, stasis logs the action as started, sees the
    # immediate exit, treats the step as finished and stops there — which is how
    # swaylock was absent for the whole idle chain while `niri msg` worked.
    # pactl is why pulseaudio appears at all — it stays off systemPackages, see
    # modules/desktop.nix. brightnessctl is for the laptop's brightness step.
    path = with pkgs; [
      bashNonInteractive
      niri
      pulseaudio
      libnotify
      swaylock
      brightnessctl
    ];
    serviceConfig = {
      Type = "simple";
      ExecStart = "${lib.getExe pkgs.stasis}";
      ExecReload = "${lib.getExe pkgs.stasis} reload";
      Restart = "on-failure";
      RestartSec = 2;
    };
  };

  systemd.user.services.cliphist-text = {
    description = "Clipboard history manager (text)";
    partOf = [ "graphical-session.target" ];
    wantedBy = [ "graphical-session.target" ];
    serviceConfig = {
      Type = "simple";
      ExecStartPre = "${pkgs.runtimeShell} -c 'mkdir -p $XDG_RUNTIME_DIR/cliphist && ${pkgs.cliphist}/bin/cliphist wipe'";
      ExecStart = "${pkgs.wl-clipboard}/bin/wl-paste --watch ${pkgs.cliphist}/bin/cliphist -db-path %t/cliphist/db store";
      Restart = "on-failure";
      RestartSec = 3;
    };
  };

  systemd.user.services.cliphist-image = {
    description = "Clipboard history manager (image)";
    partOf = [ "graphical-session.target" ];
    after = [ "cliphist-text.service" ];
    wantedBy = [ "graphical-session.target" ];
    serviceConfig = {
      Type = "simple";
      ExecStart = "${pkgs.wl-clipboard}/bin/wl-paste --type image --watch ${pkgs.cliphist}/bin/cliphist -db-path %t/cliphist/db store";
      Restart = "on-failure";
      RestartSec = 3;
    };
  };

  # Night light stays disabled by default: it is a user toggle. Enabling it
  # here would create a system-scope symlink that overrides any
  # `systemctl --user disable`.
  systemd.user.services.wlsunset = {
    description = "Wlsunset night light (blue light filter)";
    partOf = [ "graphical-session.target" ];
    after = [ "graphical-session.target" "kanshi.service" ];
    wantedBy = [ ];
    serviceConfig = {
      Type = "simple";
      ExecStartPre = "${pkgs.coreutils}/bin/sleep 2";
      ExecStart = "${lib.getExe pkgs.wlsunset} -T 6500 -t 5000 -S 00:00 -s 00:01";
      Restart = "on-failure";
      RestartSec = 3;
    };
  };

  # The polkit agent is not a service here: niri spawns it via
  # spawn-at-startup in defaults/xdg/niri/config.kdl. Only the FHS path it
  # references has to exist — see modules/desktop.nix.
}