home-manager/modules/programs/alot.nix

# alot config loader is sensitive to leading space !
{ config, lib, pkgs, ... }:

with lib;

let

  cfg = config.programs.alot;

  enabledAccounts =
    filter (a: a.notmuch.enable) (attrValues config.accounts.email.accounts);

  # sorted: primary first
  alotAccounts = sort (a: b: !(a.primary -> b.primary)) enabledAccounts;

  boolStr = v: if v then "True" else "False";

  mkKeyValue = key: value:
    let value' = if isBool value then boolStr value else toString value;
    in "${key} = ${value'}";

  mk2ndLevelSectionName = name: "[" + name + "]";

  tagSubmodule = types.submodule {
    options = {
      translated = mkOption {
        type = types.nullOr types.str;
        description = lib.mdDoc ''
          Fixed string representation for this tag. The tag can be
          hidden from view, if the key translated is set to
          `""`, the empty string.
        '';
      };

      translation = mkOption {
        type = types.nullOr types.str;
        default = null;
        description = lib.mdDoc ''
          A pair of strings that define a regular substitution to
          compute the string representation on the fly using
          `re.sub`.
        '';
      };

      normal = mkOption {
        type = types.nullOr types.str;
        default = null;
        example = "'','', 'white','light red', 'white','#d66'";
        description = lib.mdDoc ''
          How to display the tag when unfocused.
          See <https://alot.readthedocs.io/en/latest/configuration/theming.html#tagstring-formatting>.
        '';
      };

      focus = mkOption {
        type = types.nullOr types.str;
        default = null;
        description = lib.mdDoc "How to display the tag when focused.";
      };
    };
  };

  accountStr = account:
    with account;
    concatStringsSep "\n" ([ "[[${name}]]" ]
      ++ mapAttrsToList (n: v: n + "=" + v) ({
        address = address;
        realname = realName;
        sendmail_command =
          optionalString (alot.sendMailCommand != null) alot.sendMailCommand;
      } // optionalAttrs (folders.sent != null) {
        sent_box = "maildir" + "://" + maildir.absPath + "/" + folders.sent;
      } // optionalAttrs (folders.drafts != null) {
        draft_box = "maildir" + "://" + maildir.absPath + "/" + folders.drafts;
      } // optionalAttrs (aliases != [ ]) {
        aliases = concatStringsSep "," aliases;
      } // optionalAttrs (gpg != null) {
        gpg_key = gpg.key;
        encrypt_by_default = if gpg.encryptByDefault then "all" else "none";
        sign_by_default = boolStr gpg.signByDefault;
      } // optionalAttrs (signature.showSignature != "none") {
        signature = pkgs.writeText "signature.txt" signature.text;
        signature_as_attachment = boolStr (signature.showSignature == "attach");
      }) ++ [ alot.extraConfig ] ++ [ "[[[abook]]]" ]
      ++ mapAttrsToList (n: v: n + "=" + v) alot.contactCompletion);

  configFile = let
    bindingsToStr = attrSet:
      concatStringsSep "\n" (mapAttrsToList (n: v: "${n} = ${v}") attrSet);
  in ''
    # Generated by Home Manager.
    # See http://alot.readthedocs.io/en/latest/configuration/config_options.html

    ${generators.toKeyValue { inherit mkKeyValue; } cfg.settings}
    ${cfg.extraConfig}
    [tags]
  '' + (let
    submoduleToAttrs = m:
      filterAttrs (name: v: name != "_module" && v != null) m;
  in generators.toINI { mkSectionName = mk2ndLevelSectionName; }
  (mapAttrs (name: x: submoduleToAttrs x) cfg.tags)) + ''
    [bindings]
    ${bindingsToStr cfg.bindings.global}

    [[bufferlist]]
    ${bindingsToStr cfg.bindings.bufferlist}
    [[search]]
    ${bindingsToStr cfg.bindings.search}
    [[envelope]]
    ${bindingsToStr cfg.bindings.envelope}
    [[taglist]]
    ${bindingsToStr cfg.bindings.taglist}
    [[thread]]
    ${bindingsToStr cfg.bindings.thread}

    [accounts]

    ${concatStringsSep "\n\n" (map accountStr alotAccounts)}
  '';

in {
  options = {
    programs.alot = {
      enable = mkOption {
        type = types.bool;
        default = false;
        example = true;
        description = lib.mdDoc ''
          Whether to enable the Alot mail user agent. Alot uses the
          Notmuch email system and will therefore be automatically
          enabled for each email account that is managed by Notmuch.
        '';
      };

      hooks = mkOption {
        type = types.lines;
        default = "";
        description = lib.mdDoc ''
          Content of the hooks file.
        '';
      };

      bindings = mkOption {
        type = types.submodule {
          options = {
            global = mkOption {
              type = types.attrsOf types.str;
              default = { };
              description = lib.mdDoc "Global keybindings.";
            };

            bufferlist = mkOption {
              type = types.attrsOf types.str;
              default = { };
              description = lib.mdDoc "Bufferlist mode keybindings.";
            };

            search = mkOption {
              type = types.attrsOf types.str;
              default = { };
              description = lib.mdDoc "Search mode keybindings.";
            };

            envelope = mkOption {
              type = types.attrsOf types.str;
              default = { };
              description = lib.mdDoc "Envelope mode keybindings.";
            };

            taglist = mkOption {
              type = types.attrsOf types.str;
              default = { };
              description = lib.mdDoc "Taglist mode keybindings.";
            };

            thread = mkOption {
              type = types.attrsOf types.str;
              default = { };
              description = lib.mdDoc "Thread mode keybindings.";
            };
          };
        };
        default = { };
        description = lib.mdDoc ''
          Keybindings.
        '';
      };

      tags = mkOption {
        type = types.attrsOf tagSubmodule;
        default = { };
        description = lib.mdDoc "How to display the tags.";
      };

      settings = mkOption {
        type = with types;
          let primitive = either (either (either str int) bool) float;
          in attrsOf primitive;
        default = {
          initial_command = "search tag:inbox AND NOT tag:killed";
          auto_remove_unread = true;
          handle_mouse = true;
          prefer_plaintext = true;
        };
        example = literalExpression ''
          {
            auto_remove_unread = true;
            ask_subject = false;
            thread_indent_replies = 2;
          }
        '';
        description = lib.mdDoc ''
          Configuration options added to alot configuration file.
        '';
      };

      extraConfig = mkOption {
        type = types.lines;
        default = "";
        description = lib.mdDoc ''
          Extra lines added to alot configuration file.
        '';
      };
    };

    accounts.email.accounts = mkOption {
      type = with types; attrsOf (submodule (import ./alot-accounts.nix pkgs));
    };
  };

  config = mkIf cfg.enable {
    home.packages = [ pkgs.alot ];

    xdg.configFile."alot/config".text = configFile;

    xdg.configFile."alot/hooks.py" = mkIf (cfg.hooks != "") {
      text = ''
        # Generated by Home Manager.
      '' + cfg.hooks;
    };
  };
}