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

let
  cfg = config.programs.music-light;

  toggleScript = pkgs.writeShellScriptBin "toggle-music-light" ''
    if systemctl --user is-active --quiet music-light.service; then
      exec systemctl --user stop music-light.service
    else
      exec systemctl --user start music-light.service
    fi
  '';

  startScript = pkgs.writeShellScriptBin "start-music-light" ''
    exec systemctl --user start music-light.service
  '';

  stopScript = pkgs.writeShellScriptBin "stop-music-light" ''
    exec systemctl --user stop music-light.service
  '';

  statusScript = pkgs.writeShellScriptBin "music-light-status" ''
    if systemctl --user is-active --quiet music-light.service; then
      echo on
    else
      echo off
    fi
  '';
in
{
  options.programs.music-light = {
    enable = lib.mkEnableOption "music-light integration managed by Home Manager";

    scriptDir = lib.mkOption {
      type = lib.types.str;
      default = "${config.home.homeDirectory}/music-light";
      example = "/home/vini/music-light";
      description = "Directory that contains `luz-musica.py`.";
    };

    pythonPath = lib.mkOption {
      type = lib.types.str;
      default = "/usr/bin/python3";
      example = "/usr/bin/python3";
      description = "Path to the host Python interpreter used by the service.";
    };

    playerctlPath = lib.mkOption {
      type = lib.types.str;
      default = "/usr/bin/playerctl";
      example = "/usr/bin/playerctl";
      description = "Path to the host `playerctl` binary used by the service.";
    };

    enableDesktopEntry = lib.mkOption {
      type = lib.types.bool;
      default = true;
      description = "Whether to create a desktop launcher that toggles the service.";
    };

    autostart = lib.mkOption {
      type = lib.types.bool;
      default = false;
      description = "Whether to start `music-light.service` automatically at login.";
    };
  };

  config = lib.mkIf cfg.enable {
    home.packages = [
      toggleScript
      startScript
      stopScript
      statusScript
    ];

    xdg.desktopEntries = lib.mkIf cfg.enableDesktopEntry {
      music-light-toggle = {
        name = "Music Light Toggle";
        comment = "Start or stop the music-light sync service";
        exec = "${toggleScript}/bin/toggle-music-light";
        terminal = false;
        categories = [ "Utility" ];
      };
    };

    systemd.user.services.music-light = {
      Unit = {
        Description = "Sync Home Assistant light color with the active media artwork";
        After = [ "graphical-session.target" "network-online.target" ];
        PartOf = [ "graphical-session.target" ];
      };

      Service = {
        Type = "simple";
        WorkingDirectory = cfg.scriptDir;
        ExecStart = "${cfg.pythonPath} ${cfg.scriptDir}/luz-musica.py";
        Restart = "on-failure";
        RestartSec = 3;
        Environment = [
          "PATH=/usr/local/bin:/usr/bin:/bin"
          "PLAYERCTL_BIN=${cfg.playerctlPath}"
        ];
      };

      Install.WantedBy = lib.mkIf cfg.autostart [ "default.target" ];
    };
  };
}