{
  lib,
  config,
  pkgs,
  ...
}: let
  cfg = config.soispha.programs.tskm;

  allProjectNames = lib.lists.flatten (lib.attrsets.mapAttrsToList mkProject cfg.projects);

  projectList = builtins.concatStringsSep "\n" allProjectNames;
  mkProject = name: value: let
    subprojects = lib.attrsets.mapAttrsToList (newName: mkProject "${name}.${newName}") value.subprojects;
  in
    [name] ++ subprojects;

  firefoxProfiles = builtins.listToAttrs (lib.imap0 (index: name:
    lib.attrsets.nameValuePair name {
      inherit name;
      # Add one here, so that we can have the default profile at id 0.
      id = index + 1;
    })
  allProjectNames);

  contexts =
    builtins.concatStringsSep "\n"
    (lib.lists.flatten
      (lib.attrsets.mapAttrsToList mkContext cfg.projects));
  mkContext = name: value: let
    subprojects =
      lib.attrsets.mapAttrsToList
      (newName: newValue: let
        finalValue =
          if newValue.prefix == ""
          then newValue // {inherit (value) prefix;}
          else newValue;
      in
        mkContext "${name}.${newName}" finalValue)
      value.subprojects;
    contextName = builtins.replaceStrings ["."] ["_"] name;
  in
    [
      ''
        context.${contextName}.rc.neorg_path=${value.prefix}/index.norg
        context.${contextName}.read=project:${name}
        context.${contextName}.write=project:${name}
      ''
    ]
    ++ subprojects;

  contextsFile =
    pkgs.writeText "contexts-file" contexts;

  projectType = lib.types.submodule {
    options = {
      name = lib.mkOption {
        type = lib.types.str;
        example = "timesinks";
        description = "The name of this project";
      };

      prefix = lib.mkOption {
        type = lib.types.str;
        default = "";
        example = "programming/zig";
        description = ''
          A prefix to append to the project neorg path.
          This can be used to group similar project's neorg directories together. '
        '';
      };

      subprojects = lib.mkOption {
        type = lib.types.attrsOf projectType;
        description = ''
          A list of subprojects.
          These can also contain subprojects.
        '';
        default = {};
      };
    };
  };
in {
  options.soispha.programs.tskm = {
    enable = lib.mkEnableOption "tskm";

    projects = lib.mkOption {
      type = lib.types.attrsOf projectType;
    };
  };

  config = lib.mkIf cfg.enable {
    soispha.programs = {
      firefox.profiles = firefoxProfiles;
      taskwarrior = {
        includeFiles = {
          tskm-contexts = contextsFile;
        };
        hooks = {
          enforce-projects =
            config.lib.taskwarrior.mkHook "on-add" [
              pkgs.jq
              pkgs.gnugrep
              pkgs.tskm
            ]
            ./taskwarrior_hooks/enforce-projects.sh;
        };
      };
    };

    home-manager.users.soispha = {
      home.sessionVariables = {
        # TODO: Remove this hard-coded path with a reference. <2025-04-04>
        "TSKM_PROJECT_FILE" = "/home/soispha/repos/nix/config/modules/common/projects.json";
      };

      programs.nixvim = {
        plugins.neorg.settings.load."core.dirman".config.workspaces = {
          tskm = "~/.local/share/tskm/notes";
        };
      };

      xdg.configFile."tskm/projects.list" = {
        text = projectList;
      };
    };
  };
}