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

let
  scriptPath = "hypr/scripts/wp-workspace-1to9.sh";

  wpScript = ''
    #!/usr/bin/env bash
    set -euo pipefail

    WALL_DIR="''${1:-$HOME/nixos_conf/wallpaperstuff/pictures}"

    : "''${XDG_RUNTIME_DIR:?XDG_RUNTIME_DIR not set}"
    : "''${HYPRLAND_INSTANCE_SIGNATURE:?HYPRLAND_INSTANCE_SIGNATURE not set}"

    SOCK="''${XDG_RUNTIME_DIR}/hypr/''${HYPRLAND_INSTANCE_SIGNATURE}/.socket2.sock"
    [[ -S "$SOCK" ]] || { echo "Hyprland socket not found: $SOCK" >&2; exit 1; }

    need() { command -v "$1" >/dev/null 2>&1 || { echo "Missing dependency: $1" >&2; exit 1; }; }
    need hyprctl
    need wpaperctl
    need socat

    get_active_ws_id() {
      if command -v jq >/dev/null 2>&1; then
        hyprctl activeworkspace -j | jq -r '.id'
      else
        hyprctl activeworkspace | awk '/workspace ID/ {print $3; exit}'
      fi
    }

    get_active_monitor() {
      if command -v jq >/dev/null 2>&1; then
        hyprctl activeworkspace -j | jq -r '.monitor'
      else
        hyprctl activeworkspace | sed -n 's/.* on monitor \([^:]*\):.*/\1/p' | head -n1
      fi
    }

    set_for_ws() {
      local ws_raw="$1"
      local ws="''${ws_raw%%:*}"
      [[ "$ws" =~ ^[1-9]$ ]] || return 0

      local img="''${WALL_DIR}/wallpaper''${ws}.jpg"
      [[ -f "$img" ]] || return 0

      local mon
      mon="$(get_active_monitor)"

      if [[ -n "''${mon:-}" ]]; then
        wpaperctl set "$img" "$mon"
      else
        wpaperctl set "$img"
      fi
    }

    preseed_1_to_9() {
      local orig
      orig="$(get_active_ws_id)"

      for ws in {1..9}; do
        hyprctl dispatch workspace "$ws" >/dev/null
        sleep 0.05
        set_for_ws "$ws"
      done

      hyprctl dispatch workspace "$orig" >/dev/null
    }

    # Start daemon if not already running
    if ! pgrep -x wpaperd >/dev/null; then
      wpaperd -d &
      sleep 0.5
    fi

    preseed_1_to_9
    set_for_ws "$(get_active_ws_id)"

    while IFS= read -r line; do
      case "$line" in
        workspace\>\>*)
          set_for_ws "''${line#workspace>>}"
          ;;
        workspacev2\>\>*)
          payload="''${line#workspacev2>>}"
          ws_id="''${payload%%,*}"
          set_for_ws "$ws_id"
          ;;
      esac
    done < <(socat -U - "UNIX-CONNECT:''${SOCK}")
  '';
in
{
  home.packages = with pkgs; [
    wpaperd
    socat
    jq
  ];

  # Write script
  xdg.configFile."${scriptPath}" = {
    text = wpScript;
    executable = true;
  };

  # Ensure Hyprland starts it
  wayland.windowManager.hyprland = {
    enable = true;

    extraConfig = ''
      exec-once = ${config.xdg.configHome}/${scriptPath}
    '';
  };
}