Forked the emersion/go-imap v1 project.

imapclient/thread.go

@@ -0,0 +1,85 @@
+package imapclient
+
+import (
+	"fmt"
+
+	"github.com/emersion/go-imap/v2"
+	"github.com/emersion/go-imap/v2/internal/imapwire"
+)
+
+// ThreadOptions contains options for the THREAD command.
+type ThreadOptions struct {
+	Algorithm      imap.ThreadAlgorithm
+	SearchCriteria *imap.SearchCriteria
+}
+
+func (c *Client) thread(numKind imapwire.NumKind, options *ThreadOptions) *ThreadCommand {
+	cmd := &ThreadCommand{}
+	enc := c.beginCommand(uidCmdName("THREAD", numKind), cmd)
+	enc.SP().Atom(string(options.Algorithm)).SP().Atom("UTF-8").SP()
+	writeSearchKey(enc.Encoder, options.SearchCriteria)
+	enc.end()
+	return cmd
+}
+
+// Thread sends a THREAD command.
+//
+// This command requires support for the THREAD extension.
+func (c *Client) Thread(options *ThreadOptions) *ThreadCommand {
+	return c.thread(imapwire.NumKindSeq, options)
+}
+
+// UIDThread sends a UID THREAD command.
+//
+// See Thread.
+func (c *Client) UIDThread(options *ThreadOptions) *ThreadCommand {
+	return c.thread(imapwire.NumKindUID, options)
+}
+
+func (c *Client) handleThread() error {
+	cmd := findPendingCmdByType[*ThreadCommand](c)
+	for c.dec.SP() {
+		data, err := readThreadList(c.dec)
+		if err != nil {
+			return fmt.Errorf("in thread-list: %v", err)
+		}
+		if cmd != nil {
+			cmd.data = append(cmd.data, *data)
+		}
+	}
+	return nil
+}
+
+// ThreadCommand is a THREAD command.
+type ThreadCommand struct {
+	commandBase
+	data []ThreadData
+}
+
+func (cmd *ThreadCommand) Wait() ([]ThreadData, error) {
+	err := cmd.wait()
+	return cmd.data, err
+}
+
+type ThreadData struct {
+	Chain      []uint32
+	SubThreads []ThreadData
+}
+
+func readThreadList(dec *imapwire.Decoder) (*ThreadData, error) {
+	var data ThreadData
+	err := dec.ExpectList(func() error {
+		var num uint32
+		if len(data.SubThreads) == 0 && dec.Number(&num) {
+			data.Chain = append(data.Chain, num)
+		} else {
+			sub, err := readThreadList(dec)
+			if err != nil {
+				return err
+			}
+			data.SubThreads = append(data.SubThreads, *sub)
+		}
+		return nil
+	})
+	return &data, err
+}