Add custom SMTP authentication supportHEADmaster

- Add SMTPUsername and SMTPPassword fields to Settings struct
- Update DoSMTP method to use custom credentials when available
- Add SMTP credential fields to all theme templates
- Support independent username/password configuration

Fixes authentication issues when using different SMTP credentials
than login credentials, useful for app-specific passwords.

5 files changed, 183 insertions, 2 deletions

diff --git a/plugins/base/public/settings.html b/plugins/base/public/settings.html
index 7acacb5..da950e4 100644
--- a/plugins/base/public/settings.html
+++ b/plugins/base/public/settings.html
@@ -9,9 +9,46 @@
 <h2>Settings</h2>
 
 <form method="post" action="">
+  <label for="from">Full name:</label>
+  <input type="text" name="from" id="from" value="{{.Settings.From}}">
+  <br><br>
+
+  <label for="signature">Message signature:</label>
+  <textarea name="signature" id="signature" rows="5">{{.Settings.Signature}}</textarea>
+  <br><br>
+
+  <label for="smtp_username">Custom SMTP Username (optional):</label>
+  <input type="text" name="smtp_username" id="smtp_username" value="{{.Settings.SMTPUsername}}" placeholder="Leave empty to use login username">
+  <br>
+  <small>Use this if your SMTP server requires different credentials than your email login</small>
+  <br><br>
+
+  <label for="smtp_password">Custom SMTP Password (optional):</label>
+  <input type="password" name="smtp_password" id="smtp_password" value="{{.Settings.SMTPPassword}}" placeholder="Leave empty to use login password">
+  <br>
+  <small>Use this if your SMTP server requires different credentials than your email login</small>
+  <br><br>
+
+  <label for="subscriptions">Subscribed folders:</label>
+  <select name="subscriptions" id="subscriptions" multiple>
+    {{ $subs := .Subscriptions }}
+    {{ range .Mailboxes }}
+    {{ if and (ne .Name "INBOX") (not (.HasAttr "\\Noselect")) }}
+    <option
+      value="{{.Name}}"
+      {{ if $subs.Has .Name }}
+      selected
+      {{ end }}
+    >{{.Name}}</option>
+    {{ end }}
+    {{ end }}
+  </select>
+  <br><br>
+
   <label for="messages_per_page">Messages per page:</label>
   <input type="number" name="messages_per_page" id="messages_per_page" required value="{{.Settings.MessagesPerPage}}">
   <br><br>
+
   <input type="submit" value="Save">
 </form>
 
diff --git a/plugins/base/routes.go b/plugins/base/routes.go
index 623a5cc..4640c93 100644
--- a/plugins/base/routes.go
+++ b/plugins/base/routes.go
@@ -1243,6 +1243,8 @@ type Settings struct {
 	Signature       string
 	From            string
 	Subscriptions   []string
+	SMTPUsername    string
+	SMTPPassword    string
 }
 
 func loadSettings(s alps.Store) (*Settings, error) {
@@ -1268,6 +1270,12 @@ func (s *Settings) check() error {
 	if len(s.From) > 512 {
 		return fmt.Errorf("Full name must be 512 characters or fewer")
 	}
+	if len(s.SMTPUsername) > 255 {
+		return fmt.Errorf("SMTP username must be 255 characters or fewer")
+	}
+	if len(s.SMTPPassword) > 255 {
+		return fmt.Errorf("SMTP password must be 255 characters or fewer")
+	}
 	return nil
 }
 
@@ -1311,6 +1319,8 @@ func handleSettings(ctx *alps.Context) error {
 		}
 		settings.Signature = ctx.FormValue("signature")
 		settings.From = ctx.FormValue("from")
+		settings.SMTPUsername = ctx.FormValue("smtp_username")
+		settings.SMTPPassword = ctx.FormValue("smtp_password")
 
 		params, err := ctx.FormParams()
 		if err != nil {
diff --git a/session.go b/session.go
index a85bff6..f241b6a 100644
--- a/session.go
+++ b/session.go
@@ -112,7 +112,23 @@ func (s *Session) DoSMTP(f func(*smtp.Client) error) error {
 	}
 	defer c.Close()
 
-	auth := sasl.NewPlainClient("", s.username, s.password)
+	// Try to get custom SMTP credentials from user settings
+	smtpUsername := s.username
+	smtpPassword := s.password
+
+	// Load settings to check for custom SMTP credentials
+	if settings, err := s.loadSMTPSettings(); err == nil {
+		// Use custom username if provided, otherwise keep login username
+		if settings.SMTPUsername != "" {
+			smtpUsername = settings.SMTPUsername
+		}
+		// Use custom password if provided, otherwise keep login password
+		if settings.SMTPPassword != "" {
+			smtpPassword = settings.SMTPPassword
+		}
+	}
+
+	auth := sasl.NewPlainClient("", smtpUsername, smtpPassword)
 	if err := c.Auth(auth); err != nil {
 		return AuthError{err}
 	}
@@ -128,6 +144,34 @@ func (s *Session) DoSMTP(f func(*smtp.Client) error) error {
 	return nil
 }
 
+// SMTPSettings represents custom SMTP authentication settings
+type SMTPSettings struct {
+	SMTPUsername string
+	SMTPPassword string
+}
+
+// loadSMTPSettings is a helper method to load SMTP settings for this session
+func (s *Session) loadSMTPSettings() (*SMTPSettings, error) {
+	const settingsKey = "base.settings"
+	var fullSettings struct {
+		MessagesPerPage int
+		Signature       string
+		From            string
+		Subscriptions   []string
+		SMTPUsername    string
+		SMTPPassword    string
+	}
+
+	if err := s.Store().Get(settingsKey, &fullSettings); err != nil {
+		return nil, err
+	}
+
+	return &SMTPSettings{
+		SMTPUsername: fullSettings.SMTPUsername,
+		SMTPPassword: fullSettings.SMTPPassword,
+	}, nil
+}
+
 // SetHTTPBasicAuth adds an Authorization header field to the request with
 // this session's credentials.
 func (s *Session) SetHTTPBasicAuth(req *http.Request) {
diff --git a/themes/alps/settings.html b/themes/alps/settings.html
index 61e76e6..c845055 100644
--- a/themes/alps/settings.html
+++ b/themes/alps/settings.html
@@ -33,6 +33,30 @@
         </div>
 
         <div class="action-group">
+          <label for="smtp_username">Custom SMTP Username (optional)</label>
+          <input
+            type="text"
+            name="smtp_username"
+            id="smtp_username"
+            value="{{.Settings.SMTPUsername}}"
+            placeholder="Leave empty to use login username"
+          />
+          <small>Use this if your SMTP server requires different credentials than your email login</small>
+        </div>
+
+        <div class="action-group">
+          <label for="smtp_password">Custom SMTP Password (optional)</label>
+          <input
+            type="password"
+            name="smtp_password"
+            id="smtp_password"
+            value="{{.Settings.SMTPPassword}}"
+            placeholder="Leave empty to use login password"
+          />
+          <small>Use this if your SMTP server requires different credentials than your email login</small>
+        </div>
+
+        <div class="action-group">
           <label for="subscriptions">Subscribed folders</label>
           <select name="subscriptions" id="subscriptions" multiple>
             {{ $subs := .Subscriptions }}
diff --git a/themes/sourcehut/settings.html b/themes/sourcehut/settings.html
index c197789..43228af 100644
--- a/themes/sourcehut/settings.html
+++ b/themes/sourcehut/settings.html
@@ -12,6 +12,72 @@
 <div class="container">
   <form method="post" class="col-md-12">
     <div class="form-group">
+      <label for="from">Full name:</label>
+      <input
+        type="text"
+        name="from"
+        id="from"
+        class="form-control"
+        value="{{.Settings.From}}"
+        placeholder="Your display name for outgoing emails"
+      />
+    </div>
+
+    <div class="form-group">
+      <label for="signature">Message signature:</label>
+      <textarea
+        name="signature"
+        id="signature"
+        class="form-control"
+        rows="5"
+        placeholder="Optional signature to append to your emails"
+      >{{.Settings.Signature}}</textarea>
+    </div>
+
+    <div class="form-group">
+      <label for="smtp_username">Custom SMTP Username (optional):</label>
+      <input
+        type="text"
+        name="smtp_username"
+        id="smtp_username"
+        class="form-control"
+        value="{{.Settings.SMTPUsername}}"
+        placeholder="Leave empty to use login username"
+      />
+      <small class="form-text text-muted">Use this if your SMTP server requires different credentials than your email login</small>
+    </div>
+
+    <div class="form-group">
+      <label for="smtp_password">Custom SMTP Password (optional):</label>
+      <input
+        type="password"
+        name="smtp_password"
+        id="smtp_password"
+        class="form-control"
+        value="{{.Settings.SMTPPassword}}"
+        placeholder="Leave empty to use login password"
+      />
+      <small class="form-text text-muted">Use this if your SMTP server requires different credentials than your email login</small>
+    </div>
+
+    <div class="form-group">
+      <label for="subscriptions">Subscribed folders:</label>
+      <select name="subscriptions" id="subscriptions" class="form-control" multiple>
+        {{ $subs := .Subscriptions }}
+        {{ range .Mailboxes }}
+        {{ if and (ne .Name "INBOX") (not (.HasAttr "\\Noselect")) }}
+        <option
+          value="{{.Name}}"
+          {{ if $subs.Has .Name }}
+          selected
+          {{ end }}
+        >{{.Name}}</option>
+        {{ end }}
+        {{ end }}
+      </select>
+    </div>
+
+    <div class="form-group">
       <label for="messages_per_page">Messages per page:</label>
       <input
         type="number"
@@ -21,6 +87,7 @@
         class="form-control"
         value="{{.Settings.MessagesPerPage}}" />
     </div>
+
     <div class="pull-right">
       <a
         href="/"
@@ -34,5 +101,4 @@
   </form>
 </div>
 
-
 {{template "foot.html"}}