notmuch: translate filter/search options to query

Translate the regular filter and search options to a notmuch query to
achieve a basic equivalence across backends for these commands.

The following examples have the same filtering effect:
	:filter -uf koni
	:filter -u from:koni
	:filter tag:unread from:koni

And ':filter -x Flagged' would translate to ':filter tag:flagged'.

Fixes: https://todo.sr.ht/~rjarry/aerc/177
Signed-off-by: Koni Marti <koni.marti@gmail.com>
Tested-by: Inwit <inwit@sindominio.net>

2 files changed, 106 insertions, 4 deletions

diff --git a/worker/notmuch/search.go b/worker/notmuch/search.go
new file mode 100644
index 00000000..e1428b45
--- /dev/null
+++ b/worker/notmuch/search.go
@@ -0,0 +1,86 @@
+//go:build notmuch
+// +build notmuch
+
+package notmuch
+
+import (
+	"strconv"
+	"strings"
+
+	"git.sr.ht/~rjarry/aerc/log"
+	"git.sr.ht/~sircmpwn/getopt"
+)
+
+type queryBuilder struct {
+	s string
+}
+
+func (q *queryBuilder) add(s string) {
+	if len(s) == 0 {
+		return
+	}
+	if len(q.s) != 0 {
+		q.s += " and "
+	}
+	q.s += "(" + s + ")"
+}
+
+func translate(args []string) (string, error) {
+	if len(args) == 0 {
+		return "", nil
+	}
+	var qb queryBuilder
+	opts, optind, err := getopt.Getopts(args, "rux:X:bat:H:f:c:d:")
+	if err != nil {
+		// if error occurs here, don't fail
+		log.Errorf("getopts failed: %v", err)
+		return strings.Join(args[1:], ""), nil
+	}
+	body := false
+	for _, opt := range opts {
+		switch opt.Option {
+		case 'r':
+			qb.add("not tag:unread")
+		case 'u':
+			qb.add("tag:unread")
+		case 'x':
+			qb.add(getParsedFlag(opt.Value))
+		case 'X':
+			qb.add("not " + getParsedFlag(opt.Value))
+		case 'H':
+			// TODO
+		case 'f':
+			qb.add("from:" + opt.Value)
+		case 't':
+			qb.add("to:" + opt.Value)
+		case 'c':
+			qb.add("cc:" + opt.Value)
+		case 'a':
+			// TODO
+		case 'b':
+			body = true
+		case 'd':
+			qb.add("date:" + strconv.Quote(opt.Value))
+		}
+	}
+	switch {
+	case body:
+		qb.add("body:" + strconv.Quote(strings.Join(args[optind:], " ")))
+	default:
+		qb.add(strings.Join(args[optind:], " "))
+	}
+	return qb.s, nil
+}
+
+func getParsedFlag(name string) string {
+	switch strings.ToLower(name) {
+	case "answered":
+		return "tag:replied"
+	case "seen":
+		return "(not tag:unread)"
+	case "flagged":
+		return "tag:flagged"
+	default:
+		return name
+	}
+}
diff --git a/worker/notmuch/worker.go b/worker/notmuch/worker.go
index 0ac37ff3..af0f279c 100644
--- a/worker/notmuch/worker.go
+++ b/worker/notmuch/worker.go
@@ -535,13 +535,19 @@ func (w *worker) handleFlagMessages(msg *types.FlagMessages) error {
 }
 
 func (w *worker) handleSearchDirectory(msg *types.SearchDirectory) error {
-	// the first item is the command (search / filter)
-	s := strings.Join(msg.Argv[1:], " ")
+	// the first item is the command (:search)
+	log.Debugf("search args: %v", msg.Argv)
+	s, err := translate(msg.Argv)
+	if err != nil {
+		log.Debugf("ERROR: %v", err)
+		return err
+	}
 	// we only want to search in the current query, so merge the two together
 	search := w.query
 	if s != "" {
 		search = fmt.Sprintf("(%v) and (%v)", w.query, s)
 	}
+	log.Debugf("search query: '%s'", search)
 	uids, err := w.uidsFromQuery(search)
 	if err != nil {
 		return err
@@ -634,9 +640,14 @@ func (w *worker) loadExcludeTags(
 func (w *worker) emitDirectoryContents(parent types.WorkerMessage) error {
 	query := w.query
 	if msg, ok := parent.(*types.FetchDirectoryContents); ok {
-		s := strings.Join(msg.FilterCriteria[1:], " ")
+		log.Debugf("filter input: '%v'", msg.FilterCriteria)
+		s, err := translate(msg.FilterCriteria)
+		if err != nil {
+			return err
+		}
 		if s != "" {
 			query = fmt.Sprintf("(%v) and (%v)", query, s)
+			log.Debugf("filter query: '%s'", query)
 		}
 	}
 	uids, err := w.uidsFromQuery(query)
@@ -658,9 +669,14 @@ func (w *worker) emitDirectoryContents(parent types.WorkerMessage) error {
 func (w *worker) emitDirectoryThreaded(parent types.WorkerMessage) error {
 	query := w.query
 	if msg, ok := parent.(*types.FetchDirectoryThreaded); ok {
-		s := strings.Join(msg.FilterCriteria[1:], " ")
+		log.Debugf("filter input: '%v'", msg.FilterCriteria)
+		s, err := translate(msg.FilterCriteria)
+		if err != nil {
+			return err
+		}
 		if s != "" {
 			query = fmt.Sprintf("(%v) and (%v)", query, s)
+			log.Debugf("filter query: '%s'", query)
 		}
 	}
 	threads, err := w.db.ThreadsFromQuery(query)