home-manager/modules/programs/alot.nix

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

with lib;

let

  cfg = config.programs.alot;

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

  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 = ''
          Fixed string representation for this tag. The tag can be
          hidden from view, if the key translated is set to
          <literal>""</literal>, the empty string.
        '';
      };

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

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

      focus = mkOption {
        type = types.nullOr types.str;
        default = null;
        description = "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;
          sent_box = "maildir" + "://" + maildir.absPath + "/" + folders.sent;
          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 = ''
        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 = ''
        Content of the hooks file.
      '';
    };

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

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

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

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

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

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

    tags = mkOption {
      type = types.attrsOf tagSubmodule;
      default = {};
      description = "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 = literalExample ''
        {
          auto_remove_unread = true;
          ask_subject = false;
          thread_indent_replies = 2;
        }
      '';
      description = ''
        Configuration options added to alot configuration file.
      '';
    };

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

  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;
    };
  };
}