nixos-configs/hosts/pinwheel/modules/hyprland/default.nix

{
  inputs,
  pkgs,
  lib,
  config,
  ...
}:
let
  enabled = config.mod.hyprland.enable;

  mod = "SUPER";

  monitorScript = pkgs.writeShellScript "hyprland-monitor-handler" ''
    INTERNAL="eDP-1"
    EXTERNAL_MONITORS="HDMI-A-1 DP-3"
    HYPRCTL="${pkgs.hyprland}/bin/hyprctl"
    JQ="${pkgs.jq}/bin/jq"

    get_active_external() {
      # Return the first connected external monitor
      for mon in $EXTERNAL_MONITORS; do
        if $HYPRCTL monitors -j | $JQ -e ".[] | select(.name == \"$mon\")" > /dev/null 2>&1; then
          echo "$mon"
          return 0
        fi
      done
      return 1
    }

    bind_workspaces() {
      local external batch=""

      if external=$(get_active_external); then
        # External monitor connected: move workspaces 1-5 to external, 6-10 to internal
        for ws in 1 2 3 4 5; do
          batch="$batch dispatch hl.dsp.workspace.move({ monitor = \"$external\", workspace = $ws });"
        done
        for ws in 6 7 8 9 10; do
          batch="$batch dispatch hl.dsp.workspace.move({ monitor = \"$INTERNAL\", workspace = $ws });"
        done
      else
        # No external monitor: move all workspaces to internal
        for ws in 1 2 3 4 5 6 7 8 9 10; do
          batch="$batch dispatch hl.dsp.workspace.move({ monitor = \"$INTERNAL\", workspace = $ws });"
        done
      fi

      $HYPRCTL --batch "$batch"
    }

    handle_event() {
      case $1 in
        monitoradded*|monitorremoved*)
          sleep 0.5
          bind_workspaces
          ;;
      esac
    }

    # Start the event listener first so monitoradded events emitted during
    # session startup are not lost in the gap before we begin reading them.
    ${pkgs.socat}/bin/socat -U - UNIX-CONNECT:"$XDG_RUNTIME_DIR/hypr/$HYPRLAND_INSTANCE_SIGNATURE/.socket2.sock" | while read -r line; do
      handle_event "$line"
    done &
    LISTENER_PID=$!

    # Give socat a moment to actually connect before the initial bind.
    sleep 0.2
    bind_workspaces

    # Re-bind once more after the DRM subsystem has had time to enumerate
    # external connectors, in case they were not yet present at session start.
    (sleep 3; bind_workspaces) &

    wait $LISTENER_PID
  '';
in
{
  options = {
    mod.hyprland = {
      enable = lib.mkEnableOption "enable hyprland module";
    };
  };

  config = lib.mkIf enabled {
    programs.hyprland = {
      enable = true;
      withUWSM = true;
      package = inputs.hyprland.packages.${pkgs.stdenv.hostPlatform.system}.hyprland;
      portalPackage =
        inputs.hyprland.packages.${pkgs.stdenv.hostPlatform.system}.xdg-desktop-portal-hyprland;

      xwayland = {
        enable = true;
      };
    };

    home-manager.users.alex = {
      wayland.windowManager.hyprland = {
        enable = true;
        systemd.enable = false;
        configType = "lua";

        settings = {
          config = {
            xwayland.force_zero_scaling = true;

            input = {
              kb_layout = "se";

              # 2 - Cursor focus will be detached from keyboard focus. Clicking on a window will move keyboard focus to that window.
              follow_mouse = 2;

              sensitivity = 0.3;
              accel_profile = "flat";
              touchpad = {
                natural_scroll = false;
                tap_and_drag = false;
              };
            };

            cursor = {
              zoom_factor = 1;
              zoom_rigid = true;
            };

            general = {
              layout = "dwindle";

              gaps_in = 0; # gaps between windows
              gaps_out = 0; # gaps between windows and monitor edges

              col = {
                active_border = "rgba(${config.lib.colors.foreground}ff)";
                inactive_border = "rgba(${config.lib.colors.background}ff)";
              };
            };

            dwindle.force_split = 2;

            misc = {
              disable_hyprland_logo = true;
              disable_splash_rendering = true;
            };

            animations.enabled = false;
          };

          monitor = [
            {
              output = "eDP-1";
              mode = "1920x1200";
              position = "auto-center-down";
              scale = "1";
            }
            {
              output = "HDMI-A-1";
              mode = "2560x1440@100";
              position = "auto-center-up";
              scale = "1";
            }
            {
              output = "DP-3";
              mode = "2560x1440@60";
              position = "auto-center-up";
              scale = "1";
            }
          ];

          # Static defaults only: a workspace can only have one `monitor` in
          # hl.workspace_rule (later calls overwrite it, unlike hyprlang's
          # rule list). The hyprland-monitors service re-dispatches these to
          # whichever external monitor is actually connected at startup and
          # on hotplug, so this only matters for the brief window before it
          # runs.
          workspace_rule = [
            {
              workspace = "1";
              monitor = "HDMI-A-1";
              default = true;
            }
            {
              workspace = "2";
              monitor = "HDMI-A-1";
            }
            {
              workspace = "3";
              monitor = "HDMI-A-1";
            }
            {
              workspace = "4";
              monitor = "HDMI-A-1";
            }
            {
              workspace = "5";
              monitor = "HDMI-A-1";
            }

            {
              workspace = "6";
              monitor = "eDP-1";
              default = true;
            }
            {
              workspace = "7";
              monitor = "eDP-1";
            }
            {
              workspace = "8";
              monitor = "eDP-1";
            }
            {
              workspace = "9";
              monitor = "eDP-1";
            }
            {
              workspace = "10";
              monitor = "eDP-1";
            }

            {
              workspace = "w[tv1]";
              gaps_out = 0;
              gaps_in = 0;
            }
            {
              workspace = "f[1]";
              gaps_out = 0;
              gaps_in = 0;
            }
          ];

          window_rule = [
            {
              name = "no-gaps-wtv1";
              match = {
                float = false;
                workspace = "w[tv1]";
              };
              border_size = 0;
              rounding = 0;
            }
            {
              name = "no-gaps-f1";
              match = {
                float = false;
                workspace = "f[1]";
              };
              border_size = 0;
              rounding = 0;
            }
            {
              # https://wiki.archlinux.org/title/Hyprland#Jetbrains_apps_focus_issues
              name = "xwayland-no-initial-focus";
              match.xwayland = true;
              no_initial_focus = true;
            }
          ];

          env = [
            { _args = [ "GDK_DPI_SCALE" "1.5" ]; }
            { _args = [ "HYPRCURSOR_THEME" "Adwaita" ]; }
            { _args = [ "HYPRCURSOR_SIZE" "24" ]; }
          ];

          on = {
            _args = [
              "hyprland.start"
              (lib.generators.mkLuaInline ''
                function()
                  hl.exec_cmd("uwsm app -- waybar")
                  hl.exec_cmd("uwsm app -- hyprctl setcursor Adwaita 24")
                end
              '')
            ];
          };

          bind =
            let
              ws =
                x:
                let
                  n = if (x + 1) < 10 then (x + 1) else 0;
                in
                builtins.toString n;

              focusWs = x: {
                _args = [
                  "${mod} + ${ws x}"
                  (lib.generators.mkLuaInline "hl.dsp.focus({ workspace = ${builtins.toString (x + 1)} })")
                ];
              };
              moveToWs = x: {
                _args = [
                  "${mod} + SHIFT + ${ws x}"
                  (lib.generators.mkLuaInline
                    "hl.dsp.window.move({ workspace = ${builtins.toString (x + 1)}, follow = false })"
                  )
                ];
              };

              select = builtins.genList focusWs 10;
              move = builtins.genList moveToWs 10;

              magnifier = pkgs.writeShellScript "magnifier" ''
                CURRENT=$(${pkgs.hyprland}/bin/hyprctl getoption cursor:zoom_factor -j | ${pkgs.jq}/bin/jq .float)
                DELTA=0.1

                UPDATED=1
                case $1 in
                  --increase)
                    UPDATED=$(echo $CURRENT + $DELTA | ${pkgs.bc}/bin/bc) ;;
                  --decrease)
                    UPDATED=$(echo $CURRENT - $DELTA | ${pkgs.bc}/bin/bc) ;;
                  --reset)
                    UPDATED=1
                esac

                if (( $(echo "$UPDATED < 1" | bc) )); then UPDATED=1; fi
                ${pkgs.hyprland}/bin/hyprctl keyword cursor:zoom_factor $UPDATED
              '';
            in
            select
            ++ move
            ++ [
              {
                _args = [
                  "${mod} + ESCAPE"
                  (lib.generators.mkLuaInline "hl.dsp.window.close()")
                ];
              }

              {
                _args = [
                  "${mod} + f"
                  (lib.generators.mkLuaInline ''hl.dsp.window.fullscreen({ mode = "maximized" })'')
                ];
              }
              {
                _args = [
                  "${mod} + SHIFT + f"
                  (lib.generators.mkLuaInline ''hl.dsp.window.float({ action = "toggle" })'')
                ];
              }

              {
                _args = [
                  "${mod} + h"
                  (lib.generators.mkLuaInline ''hl.dsp.focus({ direction = "left" })'')
                ];
              }
              {
                _args = [
                  "${mod} + j"
                  (lib.generators.mkLuaInline ''hl.dsp.focus({ direction = "down" })'')
                ];
              }
              {
                _args = [
                  "${mod} + k"
                  (lib.generators.mkLuaInline ''hl.dsp.focus({ direction = "up" })'')
                ];
              }
              {
                _args = [
                  "${mod} + l"
                  (lib.generators.mkLuaInline ''hl.dsp.focus({ direction = "right" })'')
                ];
              }

              {
                _args = [
                  "${mod} + CONTROL + 1"
                  (lib.generators.mkLuaInline ''hl.dsp.exec_cmd("${magnifier} --increase")'')
                ];
              }
              {
                _args = [
                  "${mod} + CONTROL + 2"
                  (lib.generators.mkLuaInline ''hl.dsp.exec_cmd("${magnifier} --decrease")'')
                ];
              }
              {
                _args = [
                  "${mod} + CONTROL + 3"
                  (lib.generators.mkLuaInline ''hl.dsp.exec_cmd("${magnifier} --reset")'')
                ];
              }

              # mouse movements: hyprland's lua API has no separate `bindm`,
              # mouse binds are plain `hl.bind` with `{ mouse = true }`.
              {
                _args = [
                  "${mod} + mouse:272" # left click
                  (lib.generators.mkLuaInline "hl.dsp.window.drag()")
                  { mouse = true; }
                ];
              }
              {
                _args = [
                  "${mod} + mouse:273" # right click
                  (lib.generators.mkLuaInline "hl.dsp.window.resize()")
                  { mouse = true; }
                ];
              }
            ];
        };
      };

      home.packages = [
        pkgs.wdisplays
        pkgs.bc
      ];

      systemd.user.services.hyprland-monitors = {
        Unit = {
          Description = "Hyprland monitor hotplug handler";
          PartOf = [ "graphical-session.target" ];
          After = [ "graphical-session.target" ];
        };
        Service = {
          Type = "simple";
          ExecStart = "${monitorScript}";
          Restart = "on-failure";
          RestartSec = 5;
        };
        Install = {
          WantedBy = [ "graphical-session.target" ];
        };
      };
    };

    # To start electron apps like `chromium` with wayland support
    environment.sessionVariables.NIXOS_OZONE_WL = "1";

    # The XDG portal is needed for screen sharing
    xdg.portal = {
      enable = true;

      # override "trace: warning: xdg-desktop-portal 1.17 reworked how portal implementations are loaded ..."
      config.common.default = "*";

      extraPortals = [ pkgs.xdg-desktop-portal-wlr ];
    };

    # openGL is needed for wayland/hyprland
    hardware.graphics.enable = true;

    boot.kernelParams = [ "i915.enable_psr=0" ];
  };
}