We build too many walls and not enough bridges

pkg/message/flags.go

@@ -0,0 +1,83 @@
+// Copyright (c) 2020 Proton Technologies AG
+//
+// This file is part of ProtonMail Bridge.
+//
+// ProtonMail Bridge is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// ProtonMail Bridge is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with ProtonMail Bridge.  If not, see <https://www.gnu.org/licenses/>.
+
+package message
+
+import (
+	"github.com/ProtonMail/proton-bridge/pkg/pmapi"
+	"github.com/emersion/go-imap"
+)
+
+//nolint[gochecknoglobals]
+var (
+	AppleMailJunkFlag      = imap.CanonicalFlag("$Junk")
+	ThunderbirdJunkFlag    = imap.CanonicalFlag("Junk")
+	ThunderbirdNonJunkFlag = imap.CanonicalFlag("NonJunk")
+)
+
+func GetFlags(m *pmapi.Message) (flags []string) {
+	if m.Unread == 0 {
+		flags = append(flags, imap.SeenFlag)
+	}
+	if !m.Has(pmapi.FlagSent) && !m.Has(pmapi.FlagReceived) {
+		flags = append(flags, imap.DraftFlag)
+	}
+	if m.Has(pmapi.FlagReplied) || m.Has(pmapi.FlagRepliedAll) {
+		flags = append(flags, imap.AnsweredFlag)
+	}
+
+	hasSpam := false
+
+	for _, l := range m.LabelIDs {
+		if l == pmapi.StarredLabel {
+			flags = append(flags, imap.FlaggedFlag)
+		}
+		if l == pmapi.SpamLabel {
+			flags = append(flags, AppleMailJunkFlag, ThunderbirdJunkFlag)
+			hasSpam = true
+		}
+	}
+
+	if !hasSpam {
+		flags = append(flags, ThunderbirdNonJunkFlag)
+	}
+
+	return
+}
+
+func ParseFlags(m *pmapi.Message, flags []string) {
+	if (m.Flags & pmapi.FlagSent) == 0 {
+		m.Flags |= pmapi.FlagReceived
+	}
+	m.Unread = 1
+	for _, f := range flags {
+		switch f {
+		case imap.SeenFlag:
+			m.Unread = 0
+		case imap.DraftFlag:
+			m.Flags &= ^pmapi.FlagSent
+			m.Flags &= ^pmapi.FlagReceived
+			m.LabelIDs = append(m.LabelIDs, pmapi.DraftLabel)
+		case imap.FlaggedFlag:
+			m.LabelIDs = append(m.LabelIDs, pmapi.StarredLabel)
+		case imap.AnsweredFlag:
+			m.Flags |= pmapi.FlagReplied
+		case AppleMailJunkFlag, ThunderbirdJunkFlag:
+			m.LabelIDs = append(m.LabelIDs, pmapi.SpamLabel)
+		}
+	}
+}