adding callout support

Author: sspaeti

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Changelog
 
 # 2026-04-17
+- **GitHub/Obsidian-style callouts in emails** — compose emails with callout syntax `> [!note]`, `> [!tip]`, `> [!warning]` for styled alert boxes in HTML emails; rendered with colored left borders, subtle backgrounds, and emoji icons using Kanagawa theme colors (crystalBlue, springGreen, carpYellow, oniViolet, autumnRed); compact spacing with emoji and title matching body text size (15px) for minimal visual intrusion; supports custom titles (`> [!note] Custom Title`), multiple paragraphs, and nested callouts; always expanded (no collapsible behavior), no JavaScript required; works in both syntaxes: `> [!note]` (with space) or `>[!note]` (without space); uses local fork of goldmark-obsidian-callout with email-optimized rendering; same syntax used in neomd's README now works in your composed emails
 - **Timer-based mark-as-read** — emails are no longer marked as read immediately when opened; instead, a configurable timer (default 7 seconds) starts when you enter the reader; if you stay for the full duration, the email is marked as `\Seen`; if you exit early (quick peek), it stays unread; prevents accidental marking when browsing through emails
 - **`mark_as_read_after_secs` config** — new `[ui]` option to control mark-as-read delay in seconds (default 7); set to `0` for immediate marking (old behavior); set to any value to customize the delay
 - **Fix: local UI state sync on mark-as-read** — inbox list now updates immediately when an email is marked as read, either via timer or manual toggle (`n`); previously the server was updated but the local UI showed stale unread indicators until manual refresh

docs/content/docs/sending.md

@@ -14,6 +14,73 @@ When attachments are present the MIME structure is upgraded automatically:
 - **Images** → `multipart/related` with `Content-ID` — displayed inline in the email body
 - **Other files** (PDF, zip, …) → `multipart/mixed` — shown as downloadable attachments
 
+## Callouts (Admonition)
+
+neomd supports GitHub/Obsidian-style [callouts](https://www.ssp.sh/brain/admonition-call-outs) through the [this extension (with my fork)](https://github.com/sspaeti/goldmark-obsidian-callout-for-neomd) for highlighted information boxes in your emails. Use the `> [!TYPE]` syntax to create styled alert boxes:
+
+This is how it looks at the recievers end:
+![neomd](images/callouts.png)
+
+```markdown
+> [!note]
+> This is a note callout with default styling
+
+> [!tip] Pro Tip
+> Use custom titles by adding text after the type
+
+> [!warning] Important
+> Callouts can have multiple paragraphs
+>
+> Just add blank blockquote lines between them
+
+> [!important]
+> Recipients see colored boxes with icons in HTML email clients
+> while plain text clients show it as a blockquote
+```
+
+**Available callout types:**
+- `[!note]` — Blue info box
+- `[!tip]` — Green success/tip box
+- `[!important]` — Purple important box
+- `[!warning]` — Yellow warning box
+- `[!caution]` — Red caution/danger box
+
+**Features:**
+- Custom titles — add text after the type: `> [!warning] Security Alert`
+- Multiple paragraphs — use `> ` (blockquote with space) for blank lines
+- Works in both syntaxes: `> [!note]` (with space) or `>[!note]` (without space)
+
+**What recipients see:**
+
+HTML email clients (Gmail, Outlook, Apple Mail) display callouts as colored boxes with:
+- Colored left border (4px solid)
+- Colored background
+- Bold title with icon
+- Proper spacing and padding
+
+>[!NOTE]
+> Plain text email clients show callouts as regular blockquotes (graceful degradation).
+
+**Example in composed email:**
+
+```markdown
+Hi team,
+
+Here's the update on the project:
+
+> [!tip] Good News
+> We're ahead of schedule! The new feature shipped yesterday.
+
+> [!warning] Action Required
+> Please review the security audit by Friday.
+>
+> Contact @security if you have questions.
+
+Thanks,
+Simon
+```
+
+
 ## Multiple From Addresses
 
 Add `[[senders]]` blocks to config to define extra identities that share an existing account's SMTP credentials:

docs/static/images/callouts.png

@@ -5,6 +5,7 @@ go 1.24.2
 require (
 	github.com/BurntSushi/toml v1.6.0
 	github.com/JohannesKaufmann/html-to-markdown v1.6.0
+	github.com/VojtaStruhar/goldmark-obsidian-callout v0.1.0
 	github.com/charmbracelet/bubbles v1.0.0
 	github.com/charmbracelet/bubbletea v1.3.10
 	github.com/charmbracelet/glamour v0.9.1
@@ -51,3 +52,5 @@ require (
 	golang.org/x/term v0.30.0 // indirect
 	golang.org/x/text v0.23.0 // indirect
 )
+
+replace github.com/VojtaStruhar/goldmark-obsidian-callout => /home/sspaeti/git/email/goldmark-obsidian-callout-for-neomd

go.mod

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 
+	callout "github.com/VojtaStruhar/goldmark-obsidian-callout"
 	"github.com/yuin/goldmark"
 	"github.com/yuin/goldmark/extension"
 	"github.com/yuin/goldmark/renderer/html"
@@ -28,16 +29,32 @@ pre{background:#f6f8fa;padding:12px;border-radius:4px;overflow:auto;font-family:
 blockquote{border-left:3px solid #ddd;color:#666;margin:0 0 1em;padding-left:1em}
 hr{border:0;border-bottom:1px solid #eee;margin:20px 0}
 img{max-width:100%%;height:auto}
+.callout{border-left:3px solid;padding:8px 12px;margin:0.8em 0;border-radius:3px;background:#f6f8fa}
+.callout-title{font-weight:600;margin-bottom:4px;display:flex;align-items:center;font-size:15px}
+.callout-icon{font-size:15px;margin-right:6px}
+.callout-title-inner{line-height:1.3}
+.callout>:last-child{margin-bottom:0}
+.callout-note{border-left-color:#7E9CD8;background:#f0f3fc}
+.callout-tip{border-left-color:#98BB6C;background:#f2f7f0}
+.callout-important{border-left-color:#957FB8;background:#f4f2f7}
+.callout-warning{border-left-color:#E6C384;background:#fdf9f0}
+.callout-caution{border-left-color:#C34043;background:#fcf0f0}
+.callout-info{border-left-color:#7FB4CA;background:#f0f6f8}
+.callout-danger{border-left-color:#E82424;background:#fef0f0}
+.callout-success{border-left-color:#76946A;background:#f1f6f0}
 </style>
 </head>
 <body>
 %s
 </body>
 </html>`
 
-// md is the goldmark renderer with GFM extensions.
+// md is the goldmark renderer with GFM extensions and callout support.
 var md = goldmark.New(
-	goldmark.WithExtensions(extension.GFM),
+	goldmark.WithExtensions(
+		extension.GFM,
+		callout.ObsidianCallout,
+	),
 	goldmark.WithRendererOptions(html.WithHardWraps()),
 )
 

internal/render/html.go

@@ -66,3 +66,105 @@ func TestToANSI_Smoke(t *testing.T) {
 		t.Fatalf("ToANSI returned error: %v", err)
 	}
 }
+
+func TestToHTML_Callout_Note(t *testing.T) {
+	md := "> [!note]\n> This is a note callout\n"
+	out, err := ToHTML(md)
+	if err != nil {
+		t.Fatalf("ToHTML returned error: %v", err)
+	}
+	// Print actual HTML for debugging
+	t.Logf("Actual HTML output:\n%s", out)
+	if !strings.Contains(out, "callout") {
+		t.Errorf("expected 'callout' class in output, got:\n%s", out)
+	}
+	if !strings.Contains(out, "callout-note") {
+		t.Errorf("expected 'callout-note' class in output, got:\n%s", out)
+	}
+	if !strings.Contains(out, "This is a note callout") {
+		t.Errorf("expected callout content in output, got:\n%s", out)
+	}
+}
+
+func TestToHTML_Callout_WithTitle(t *testing.T) {
+	md := "> [!warning] Custom Warning Title\n> This is a warning\n"
+	out, err := ToHTML(md)
+	if err != nil {
+		t.Fatalf("ToHTML returned error: %v", err)
+	}
+	if !strings.Contains(out, "callout-warning") {
+		t.Errorf("expected 'callout-warning' class in output, got:\n%s", out)
+	}
+	if !strings.Contains(out, "Custom Warning Title") {
+		t.Errorf("expected custom title in output, got:\n%s", out)
+	}
+	if !strings.Contains(out, "This is a warning") {
+		t.Errorf("expected callout content in output, got:\n%s", out)
+	}
+}
+
+func TestToHTML_Callout_MultiParagraph(t *testing.T) {
+	md := "> [!tip]\n> First paragraph\n> \n> Second paragraph\n"
+	out, err := ToHTML(md)
+	if err != nil {
+		t.Fatalf("ToHTML returned error: %v", err)
+	}
+	if !strings.Contains(out, "callout-tip") {
+		t.Errorf("expected 'callout-tip' class in output, got:\n%s", out)
+	}
+	if !strings.Contains(out, "First paragraph") {
+		t.Errorf("expected first paragraph in output, got:\n%s", out)
+	}
+	if !strings.Contains(out, "Second paragraph") {
+		t.Errorf("expected second paragraph in output, got:\n%s", out)
+	}
+}
+
+func TestToHTML_Callout_Types(t *testing.T) {
+	tests := []struct {
+		name      string
+		callType  string
+		wantClass string
+	}{
+		{"note", "note", "callout-note"},
+		{"tip", "tip", "callout-tip"},
+		{"important", "important", "callout-important"},
+		{"warning", "warning", "callout-warning"},
+		{"caution", "caution", "callout-caution"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			md := "> [!" + tt.callType + "]\n> Test content\n"
+			out, err := ToHTML(md)
+			if err != nil {
+				t.Fatalf("ToHTML returned error: %v", err)
+			}
+			if !strings.Contains(out, tt.wantClass) {
+				t.Errorf("expected '%s' class in output, got:\n%s", tt.wantClass, out)
+			}
+		})
+	}
+}
+
+func TestToHTML_Callout_NoSpaceSyntax(t *testing.T) {
+	// Test if >[!note] works without space after >
+	md := ">[!note] No Space Test\n>This tests the syntax without space\n"
+	out, err := ToHTML(md)
+	if err != nil {
+		t.Fatalf("ToHTML returned error: %v", err)
+	}
+	// Check if it rendered as callout or as regular blockquote
+	if strings.Contains(out, "callout-note") {
+		// Success: >[!note] (no space) DOES work as callout
+		if !strings.Contains(out, "No Space Test") {
+			t.Errorf("expected title in callout output, got:\n%s", out)
+		}
+		if !strings.Contains(out, "This tests the syntax without space") {
+			t.Errorf("expected content in callout output, got:\n%s", out)
+		}
+	} else {
+		// Failure: rendered as blockquote instead
+		t.Errorf(">[!note] without space did not render as callout. Use '> [!note]' (with space) instead. Got:\n%s", out)
+	}
+}