neomutt: Initial IMAP support (#4597)

neomutt: Updated options and added tests

neomutt: Added test for individual mailbox type

neomutt: Formatted code

neomutt: Enable ssl_force_tls based on IMAP instead of SMTP

neomutt: Applied suggestions from @chayleaf

neomutt: fix breaking tests

modules/programs/neomutt-accounts.nix

@@ -17,6 +17,14 @@ let
         default = null;
         description = "Name to display";
       };
+
+      type = mkOption {
+        type = types.nullOr (types.enum [ "maildir" "imap" ]);
+        example = "imap";
+        default = null;
+        description =
+          "Whether this mailbox is a maildir folder or an IMAP mailbox";
+      };
     };
   };
 
@@ -75,6 +83,14 @@ in {
       description = "Use a different name as mailbox name";
     };
 
+    mailboxType = mkOption {
+      type = types.enum [ "maildir" "imap" ];
+      default = "maildir";
+      example = "imap";
+      description =
+        "Whether this account uses maildir folders or IMAP mailboxes";
+    };
+
     extraMailboxes = mkOption {
       type = with types; listOf (either str (submodule extraMailboxOptions));
       default = [ ];

modules/programs/neomutt.nix

@@ -8,6 +8,59 @@ let
   neomuttAccounts =
     filter (a: a.neomutt.enable) (attrValues config.accounts.email.accounts);
 
+  accountCommandNeeded = any (a:
+    a.neomutt.enable && (a.neomutt.mailboxType == "imap"
+      || (any (m: !isString m && m.type == "imap") a.neomutt.extraMailboxes)))
+    (attrValues config.accounts.email.accounts);
+
+  accountCommand = let
+    imapAccounts = filter (a:
+      a.neomutt.enable && a.imap.host != null && a.userName != null
+      && a.passwordCommand != null) (attrValues config.accounts.email.accounts);
+    accountCase = account:
+      let passwordCmd = toString account.passwordCommand;
+      in ''
+        ${account.userName}@${account.imap.host})
+            found=1
+            username="${account.userName}"
+            password="$(${passwordCmd})"
+            ;;'';
+  in pkgs.writeShellScriptBin "account-command.sh" ''
+    # Automatically set login variables based on the current account.
+    # This requires NeoMutt >= 2022-05-16
+
+    while [ ! -z "$1" ]; do
+      case "$1" in
+         --hostname)
+             shift
+             hostname="$1"
+             ;;
+         --username)
+             shift
+             username="$1@"
+             ;;
+         --type)
+            shift
+            type="$1"
+             ;;
+         *)
+            exit 1
+            ;;
+      esac
+    shift
+    done
+
+    found=
+    case "''${username}''${hostname}" in
+      ${concatMapStringsSep "\n" accountCase imapAccounts}
+    esac
+
+    if [ -n "$found" ]; then
+      echo "username: $username"
+      echo "password: $password"
+    fi
+  '';
+
   sidebarModule = types.submodule {
     options = {
       enable = mkEnableOption "sidebar support";
@@ -101,6 +154,21 @@ let
 
   accountFilename = account: config.xdg.configHome + "/neomutt/" + account.name;
 
+  accountRootIMAP = account:
+    let
+      userName =
+        lib.optionalString (account.userName != null) "${account.userName}@";
+      port = lib.optionalString (account.imap.port != null)
+        ":${toString account.imap.port}";
+      protocol = if account.imap.tls.enable then "imaps" else "imap";
+    in "${protocol}://${userName}${account.imap.host}${port}";
+
+  accountRoot = account:
+    if account.neomutt.mailboxType == "imap" then
+      accountRootIMAP account
+    else
+      account.maildir.absPath;
+
   genCommonFolderHooks = account:
     with account; {
       from = "'${address}'";
@@ -128,12 +196,12 @@ let
         smtp_pass = ''"`${passCmd}`"'';
       };
 
-  genMaildirAccountConfig = account:
+  genAccountConfig = account:
     with account;
     let
       folderHook = mapAttrsToList setOption (genCommonFolderHooks account
         // optionalAttrs cfg.changeFolderWhenSourcingAccount {
-          folder = "'${account.maildir.absPath}'";
+          folder = "'${accountRoot account}'";
         });
     in ''
       ${concatStringsSep "\n" folderHook}
@@ -145,29 +213,40 @@ let
         "mailboxes"
       else
         ''named-mailboxes "${account.neomutt.mailboxName}"'';
+      mailroot = accountRoot account;
+      hookName = if account.neomutt.mailboxType == "imap" then
+        "account-hook"
+      else
+        "folder-hook";
       extraMailboxes = concatMapStringsSep "\n" (extra:
-        if isString extra then
-          ''mailboxes "${account.maildir.absPath}/${extra}"''
+        let
+          mailboxroot = if !isString extra && extra.type == "imap" then
+            accountRootIMAP account
+          else if !isString extra && extra.type == "maildir" then
+            account.maildir.absPath
+          else
+            mailroot;
+        in if isString extra then
+          ''mailboxes "${mailboxroot}/${extra}"''
         else if extra.name == null then
-          ''mailboxes "${account.maildir.absPath}/${extra.mailbox}"''
+          ''mailboxes "${mailboxroot}/${extra.mailbox}"''
         else
-          ''
-            named-mailboxes "${extra.name}" "${account.maildir.absPath}/${extra.mailbox}"'')
+          ''named-mailboxes "${extra.name}" "${mailboxroot}/${extra.mailbox}"'')
         account.neomutt.extraMailboxes;
     in with account; ''
       # register account ${name}
-      ${mailboxes} "${maildir.absPath}/${folders.inbox}"
+      ${mailboxes} "${mailroot}/${folders.inbox}"
       ${extraMailboxes}
-      folder-hook ${maildir.absPath}/ " \
+      ${hookName} ${mailroot}/ " \
           source ${accountFilename account} "
     '';
 
   mraSection = account:
     with account;
-    if account.maildir != null then
-      genMaildirAccountConfig account
+    if account.imap.host != null || account.maildir != null then
+      genAccountConfig account
     else
-      throw "Only maildir is supported at the moment";
+      throw "Only maildir and IMAP is supported at the moment";
 
   optionsStr = attrs: concatStringsSep "\n" (mapAttrsToList setOption attrs);
 
@@ -219,7 +298,7 @@ let
     in ''
       # Generated by Home Manager.
       set ssl_force_tls = ${
-        lib.hm.booleans.yesNo (smtp.tls.enable || smtp.tls.useStartTls)
+        lib.hm.booleans.yesNo (imap.tls.enable || imap.tls.useStartTls)
       }
       set certificate_file=${toString config.accounts.email.certificatesFile}
 
@@ -366,7 +445,11 @@ in {
         "source ${pkgs.neomutt}/share/doc/neomutt/vim-keys/vim-keys.rc"}
 
         # Register accounts
-        ${concatMapStringsSep "\n" registerAccount neomuttAccounts}
+        ${
+          optionalString (accountCommandNeeded) ''
+            set account_command = '${accountCommand}/bin/account-command.sh'
+          ''
+        }${concatMapStringsSep "\n" registerAccount neomuttAccounts}
 
         # Source primary account
         source ${accountFilename primary}