feat(mail): add email priority support for compose and read

shortcuts/mail/helpers.go

@@ -1163,6 +1163,7 @@ func buildMessageOutput(msg map[string]interface{}, html bool) map[string]interf
 	out["date_formatted"] = normalized.DateFormatted
 	out["message_state_text"] = normalized.MessageStateText
 	if normalized.PriorityType != "" {
+		out["priority_type"] = normalized.PriorityType
 		out["priority_type_text"] = normalized.PriorityTypeText
 	}
 	out["body_plain_text"] = normalized.BodyPlainText
@@ -1241,11 +1242,22 @@ func buildMessageForCompose(msg map[string]interface{}, urlMap map[string]string
 	out.MessageStateText = messageStateText(state)
 	out.FolderID = strVal(msg["folder_id"])
 	out.LabelIDs = toStringList(msg["label_ids"])
+	// Priority: prefer label_ids (HIGH_PRIORITY/LOW_PRIORITY), fall back to priority_type field.
 	priorityType := strVal(msg["priority_type"])
 	out.PriorityType = priorityType
 	if priorityType != "" {
 		out.PriorityTypeText = priorityTypeText(priorityType)
 	}
+	for _, label := range out.LabelIDs {
+		switch label {
+		case "HIGH_PRIORITY":
+			out.PriorityType = "1"
+			out.PriorityTypeText = "high"
+		case "LOW_PRIORITY":
+			out.PriorityType = "5"
+			out.PriorityTypeText = "low"
+		}
+	}
 	if securityLevel := toSecurityLevel(msg["security_level"]); securityLevel != nil {
 		out.SecurityLevel = securityLevel
 	}
@@ -1708,6 +1720,48 @@ func priorityTypeText(priorityType string) string {
 	}
 }
 
+// priorityFlag is the common flag definition for --priority, shared by all compose shortcuts.
+var priorityFlag = common.Flag{
+	Name: "priority",
+	Desc: "Email priority: high, normal, low. If omitted, no priority header is set.",
+}
+
+// parsePriority parses the --priority flag value and returns the X-Cli-Priority
+// header value. Returns "" if the priority should not be set (empty or "normal").
+func parsePriority(value string) (string, error) {
+	switch strings.ToLower(strings.TrimSpace(value)) {
+	case "":
+		return "", nil
+	case "high":
+		return "1", nil
+	case "normal":
+		return "", nil
+	case "low":
+		return "5", nil
+	default:
+		return "", fmt.Errorf("invalid --priority value %q: expected high, normal, or low", value)
+	}
+}
+
+// validatePriorityFlag validates the --priority flag value in Validate, so invalid
+// values are caught before Execute (and before dry-run prints an API plan).
+func validatePriorityFlag(runtime *common.RuntimeContext) error {
+	v := runtime.Str("priority")
+	if v == "" {
+		return nil
+	}
+	_, err := parsePriority(v)
+	return err
+}
+
+// applyPriority sets the X-Cli-Priority header on the EML builder if priority is non-empty.
+func applyPriority(bld emlbuilder.Builder, priority string) emlbuilder.Builder {
+	if priority == "" {
+		return bld
+	}
+	return bld.Header("X-Cli-Priority", priority)
+}
+
 // parseNetAddrs converts a comma-separated address string to []net/mail.Address.
 // It reuses ParseMailboxList for display-name-aware parsing and deduplicates
 // by email address (case-insensitive), preserving the first occurrence.

shortcuts/mail/helpers_test.go

@@ -1077,3 +1077,143 @@ func TestValidateSendTime_Valid(t *testing.T) {
 		t.Fatalf("expected nil for valid future send-time, got %v", err)
 	}
 }
+
+func TestParsePriority(t *testing.T) {
+	cases := []struct {
+		name    string
+		input   string
+		want    string
+		wantErr bool
+	}{
+		{"empty", "", "", false},
+		{"high", "high", "1", false},
+		{"normal", "normal", "", false},
+		{"low", "low", "5", false},
+		{"case-insensitive HIGH", "HIGH", "1", false},
+		{"whitespace padding", "  low  ", "5", false},
+		{"invalid", "urgent", "", true},
+		{"numeric not accepted", "1", "", true},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			got, err := parsePriority(tc.input)
+			if tc.wantErr {
+				if err == nil {
+					t.Fatalf("parsePriority(%q): expected error, got nil", tc.input)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("parsePriority(%q): unexpected error: %v", tc.input, err)
+			}
+			if got != tc.want {
+				t.Errorf("parsePriority(%q) = %q, want %q", tc.input, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestBuildMessageOutput_PriorityFromLabels(t *testing.T) {
+	cases := []struct {
+		name         string
+		labels       []interface{}
+		priorityType string
+		wantType     string
+		wantText     string
+	}{
+		{"high from label", []interface{}{"UNREAD", "HIGH_PRIORITY"}, "", "1", "high"},
+		{"low from label", []interface{}{"LOW_PRIORITY"}, "", "5", "low"},
+		{"no priority label", []interface{}{"UNREAD"}, "", "", ""},
+		{"label overrides priority_type field", []interface{}{"HIGH_PRIORITY"}, "5", "1", "high"},
+		{"priority_type fallback when no label", []interface{}{"UNREAD"}, "1", "1", "high"},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			msg := map[string]interface{}{
+				"message_id": "m1",
+				"label_ids":  tc.labels,
+			}
+			if tc.priorityType != "" {
+				msg["priority_type"] = tc.priorityType
+			}
+			out := buildMessageOutput(msg, false)
+			gotText, _ := out["priority_type_text"].(string)
+			if gotText != tc.wantText {
+				t.Errorf("priority_type_text = %q, want %q", gotText, tc.wantText)
+			}
+			gotType, _ := out["priority_type"].(string)
+			if gotType != tc.wantType {
+				t.Errorf("priority_type = %q, want %q", gotType, tc.wantType)
+			}
+		})
+	}
+}
+
+func TestApplyPriority(t *testing.T) {
+	// Empty priority: EML must not contain X-Cli-Priority header.
+	emptyBld := emlbuilder.New().
+		From("", "sender@example.com").
+		To("", "recipient@example.com").
+		Subject("no priority").
+		TextBody([]byte("body"))
+	emptyBld = applyPriority(emptyBld, "")
+	raw, err := emptyBld.BuildBase64URL()
+	if err != nil {
+		t.Fatalf("build EML failed: %v", err)
+	}
+	eml := decodeBase64URL(raw)
+	if strings.Contains(eml, "X-Cli-Priority") {
+		t.Errorf("expected no X-Cli-Priority header when priority is empty, got EML:\n%s", eml)
+	}
+
+	// Non-empty priority: header must be present with the exact value.
+	highBld := emlbuilder.New().
+		From("", "sender@example.com").
+		To("", "recipient@example.com").
+		Subject("high priority").
+		TextBody([]byte("body"))
+	highBld = applyPriority(highBld, "1")
+	raw, err = highBld.BuildBase64URL()
+	if err != nil {
+		t.Fatalf("build EML failed: %v", err)
+	}
+	eml = decodeBase64URL(raw)
+	if !strings.Contains(eml, "X-Cli-Priority: 1") {
+		t.Errorf("expected X-Cli-Priority: 1 in EML, got:\n%s", eml)
+	}
+}
+
+func TestValidatePriorityFlag(t *testing.T) {
+	makeRuntime := func(priority string) *common.RuntimeContext {
+		cmd := &cobra.Command{Use: "test"}
+		cmd.Flags().String("priority", "", "")
+		if priority != "" {
+			_ = cmd.Flags().Set("priority", priority)
+		}
+		return common.TestNewRuntimeContext(cmd, nil)
+	}
+
+	cases := []struct {
+		name     string
+		priority string
+		wantErr  bool
+	}{
+		{"empty ok", "", false},
+		{"high ok", "high", false},
+		{"normal ok", "normal", false},
+		{"low ok", "low", false},
+		{"invalid urgent", "urgent", true},
+		{"invalid numeric", "1", true},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			err := validatePriorityFlag(makeRuntime(tc.priority))
+			if tc.wantErr && err == nil {
+				t.Errorf("validatePriorityFlag(%q): expected error, got nil", tc.priority)
+			}
+			if !tc.wantErr && err != nil {
+				t.Errorf("validatePriorityFlag(%q): unexpected error: %v", tc.priority, err)
+			}
+		})
+	}
+}

shortcuts/mail/mail_draft_create.go

@@ -47,6 +47,7 @@
 		{Name: "attach", Desc: "Optional. Regular attachment file paths (relative path only). Separate multiple paths with commas. Each path must point to a readable local file."},
 		{Name: "inline", Desc: "Optional. Inline images as a JSON array. Each entry: {\"cid\":\"<unique-id>\",\"file_path\":\"<relative-path>\"}. All file_path values must be relative paths. Cannot be used with --plain-text. CID images are embedded via <img src=\"cid:...\"> in the HTML body. CID is a unique identifier, e.g. a random hex string like \"a1b2c3d4e5f6a7b8c9d0\"."},
 		signatureFlag,
+		priorityFlag,
 	},
 	DryRun: func(ctx context.Context, runtime *common.RuntimeContext) *common.DryRunAPI {
 		input, err := parseDraftCreateInput(runtime)
@@ -79,19 +80,23 @@
 		if err := validateComposeInlineAndAttachments(runtime.FileIO(), runtime.Str("attach"), runtime.Str("inline"), runtime.Bool("plain-text"), runtime.Str("body")); err != nil {
 			return err
 		}
-		return nil
+		return validatePriorityFlag(runtime)
 	},
 	Execute: func(ctx context.Context, runtime *common.RuntimeContext) error {
 		input, err := parseDraftCreateInput(runtime)
 		if err != nil {
 			return err
 		}
+		priority, err := parsePriority(runtime.Str("priority"))
+		if err != nil {
+			return err
+		}
 		mailboxID := resolveComposeMailboxID(runtime)
 		sigResult, err := resolveSignature(ctx, runtime, mailboxID, runtime.Str("signature-id"), runtime.Str("from"))
 		if err != nil {
 			return err
 		}
-		rawEML, err := buildRawEMLForDraftCreate(runtime, input, sigResult)
+		rawEML, err := buildRawEMLForDraftCreate(runtime, input, sigResult, priority)
 		if err != nil {
 			return err
 		}
@@ -129,7 +134,7 @@
 	return input, nil
 }
 
-func buildRawEMLForDraftCreate(runtime *common.RuntimeContext, input draftCreateInput, sigResult *signatureResult) (string, error) {
+func buildRawEMLForDraftCreate(runtime *common.RuntimeContext, input draftCreateInput, sigResult *signatureResult, priority string) (string, error) {
 	senderEmail := resolveComposeSenderEmail(runtime)
 	if senderEmail == "" {
 		return "", fmt.Errorf("unable to determine sender email; please specify --from explicitly")
@@ -190,6 +195,7 @@
 	} else {
 		bld = bld.TextBody([]byte(input.Body))
 	}
+	bld = applyPriority(bld, priority)
 	allFilePaths := append(append(splitByComma(input.Attach), inlineSpecFilePaths(inlineSpecs)...), autoResolvedPaths...)
 	if err := checkAttachmentSizeLimit(runtime.FileIO(), allFilePaths, 0); err != nil {
 		return "", err

shortcuts/mail/mail_draft_create_test.go

@@ -33,7 +33,7 @@ func TestBuildRawEMLForDraftCreate_ResolvesLocalImages(t *testing.T) {
 		Body:    `<p>Hello</p><p><img src="./test_image.png" /></p>`,
 	}
 
-	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil)
+	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "")
 	if err != nil {
 		t.Fatalf("buildRawEMLForDraftCreate() error = %v", err)
 	}
@@ -58,7 +58,7 @@ func TestBuildRawEMLForDraftCreate_NoLocalImages(t *testing.T) {
 		Body:    `<p>Hello <b>world</b></p>`,
 	}
 
-	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil)
+	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "")
 	if err != nil {
 		t.Fatalf("buildRawEMLForDraftCreate() error = %v", err)
 	}
@@ -93,7 +93,7 @@ func TestBuildRawEMLForDraftCreate_AutoResolveCountedInSizeLimit(t *testing.T) {
 		Attach:  "./big.txt",
 	}
 
-	_, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil)
+	_, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "")
 	if err == nil {
 		t.Fatal("expected size limit error when auto-resolved image + attachment exceed 25MB")
 	}
@@ -113,7 +113,7 @@ func TestBuildRawEMLForDraftCreate_OrphanedInlineSpecError(t *testing.T) {
 		Inline:  `[{"cid":"orphan","file_path":"./unused.png"}]`,
 	}
 
-	_, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil)
+	_, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "")
 	if err == nil {
 		t.Fatal("expected error for orphaned --inline CID not referenced in body")
 	}
@@ -133,7 +133,7 @@ func TestBuildRawEMLForDraftCreate_MissingCIDRefError(t *testing.T) {
 		Inline:  `[{"cid":"present","file_path":"./present.png"}]`,
 	}
 
-	_, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil)
+	_, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "")
 	if err == nil {
 		t.Fatal("expected error for missing CID reference")
 	}
@@ -142,6 +142,40 @@ func TestBuildRawEMLForDraftCreate_MissingCIDRefError(t *testing.T) {
 	}
 }
 
+func TestBuildRawEMLForDraftCreate_WithPriority(t *testing.T) {
+	input := draftCreateInput{
+		From:    "sender@example.com",
+		Subject: "priority test",
+		Body:    `<p>Hello</p>`,
+	}
+
+	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "1")
+	if err != nil {
+		t.Fatalf("buildRawEMLForDraftCreate() error = %v", err)
+	}
+	eml := decodeBase64URL(rawEML)
+	if !strings.Contains(eml, "X-Cli-Priority: 1") {
+		t.Errorf("expected X-Cli-Priority: 1 in EML, got:\n%s", eml)
+	}
+}
+
+func TestBuildRawEMLForDraftCreate_NoPriority(t *testing.T) {
+	input := draftCreateInput{
+		From:    "sender@example.com",
+		Subject: "no priority",
+		Body:    `<p>Hello</p>`,
+	}
+
+	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "")
+	if err != nil {
+		t.Fatalf("buildRawEMLForDraftCreate() error = %v", err)
+	}
+	eml := decodeBase64URL(rawEML)
+	if strings.Contains(eml, "X-Cli-Priority") {
+		t.Errorf("expected no X-Cli-Priority header when priority is empty, got:\n%s", eml)
+	}
+}
+
 func TestBuildRawEMLForDraftCreate_PlainTextSkipsResolve(t *testing.T) {
 	chdirTemp(t)
 	os.WriteFile("img.png", []byte{0x89, 'P', 'N', 'G', 0x0D, 0x0A, 0x1A, 0x0A}, 0o644)
@@ -153,7 +187,7 @@ func TestBuildRawEMLForDraftCreate_PlainTextSkipsResolve(t *testing.T) {
 		PlainText: true,
 	}
 
-	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil)
+	rawEML, err := buildRawEMLForDraftCreate(newRuntimeWithFrom("sender@example.com"), input, nil, "")
 	if err != nil {
 		t.Fatalf("buildRawEMLForDraftCreate() error = %v", err)
 	}

shortcuts/mail/mail_draft_edit.go

@@ -33,6 +33,7 @@ var MailDraftEdit = common.Shortcut{
 		{Name: "set-bcc", Desc: "Replace the entire Bcc recipient list with the addresses provided here. Separate multiple addresses with commas. Display-name format is supported."},
 		{Name: "patch-file", Desc: "Edit entry point for body edits, incremental recipient changes, header edits, attachment changes, or inline-image changes. All body edits MUST go through --patch-file. Two body ops: set_body (full replacement including quote) and set_reply_body (replaces only user-authored content, auto-preserves quote block). Run --inspect first to check has_quoted_content, then --print-patch-template for the JSON structure. Relative path only."},
 		{Name: "print-patch-template", Type: "bool", Desc: "Print the JSON template and supported operations for the --patch-file flag. Recommended first step before generating a patch file. No draft read or write is performed."},
+		{Name: "set-priority", Desc: "Set email priority: high, normal, low. Setting 'normal' removes any existing priority header."},
 		{Name: "inspect", Type: "bool", Desc: "Inspect the draft without modifying it. Returns the draft projection including subject, recipients, body summary, has_quoted_content (whether the draft contains a reply/forward quote block), attachments_summary (with part_id and cid for each attachment), and inline_summary. Run this BEFORE editing body to check has_quoted_content: if true, use set_reply_body in --patch-file to preserve the quote; if false, use set_body."},
 	},
 	DryRun: func(ctx context.Context, runtime *common.RuntimeContext) *common.DryRunAPI {
@@ -276,6 +277,19 @@ func buildDraftEditPatch(runtime *common.RuntimeContext) (draftpkg.Patch, error)
 	setRecipients("cc", runtime.Str("set-cc"))
 	setRecipients("bcc", runtime.Str("set-bcc"))
 
+	// --set-priority → inject set_header / remove_header op
+	if setPriority := runtime.Str("set-priority"); setPriority != "" {
+		headerVal, pErr := parsePriority(setPriority)
+		if pErr != nil {
+			return patch, pErr
+		}
+		if headerVal != "" {
+			patch.Ops = append(patch.Ops, draftpkg.PatchOp{Op: "set_header", Name: "X-Cli-Priority", Value: headerVal})
+		} else {
+			patch.Ops = append(patch.Ops, draftpkg.PatchOp{Op: "remove_header", Name: "X-Cli-Priority"})
+		}
+	}
+
 	if len(patch.Ops) == 0 {
 		return patch, output.ErrValidation("at least one edit operation is required; use direct flags such as --set-subject/--set-to, or use --patch-file for body edits and other advanced operations (run --print-patch-template first)")
 	}