From 2c8167557861692d84f8b3b8c19e294ed55fe85d Mon Sep 17 00:00:00 2001
From: Nick Thomas <me@ur.gs>
Date: Mon, 5 Mar 2018 23:37:54 +0000
Subject: [PATCH] Add the beginnings of SMTP session management

---
 internal/smtp/server.go  | 20 ++++++++++++++++++--
 internal/smtp/session.go | 32 ++++++++++++++++++++++++++++++++
 internal/store/store.go  |  4 ++--
 3 files changed, 52 insertions(+), 4 deletions(-)
 create mode 100644 internal/smtp/session.go

diff --git a/internal/smtp/server.go b/internal/smtp/server.go
index fdb419a..539d2fd 100644
--- a/internal/smtp/server.go
+++ b/internal/smtp/server.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"io"
 	"log"
+	"sync/atomic"
 
 	"github.com/emersion/go-smtp"
 
@@ -27,8 +28,10 @@ func NewServer(cancel context.CancelFunc, datastore store.Interface, submission
 	out.server.TLSConfig = datastore.TLSConfig()
 
 	if submission {
+		out.name = "submission"
 		out.server.Addr = ":587"
 	} else {
+		out.name = "SMTP"
 		out.server.Addr = ":25"
 	}
 
@@ -36,9 +39,13 @@ func NewServer(cancel context.CancelFunc, datastore store.Interface, submission
 }
 
 type concrete struct {
+	name   string
 	cancel context.CancelFunc
 	store  store.Interface
 	server *smtp.Server
+
+	// Session IDs
+	sid uint64
 }
 
 func (c *concrete) Run() {
@@ -52,8 +59,17 @@ func (c *concrete) Run() {
 }
 
 // backend implementation for go-smtp
-func (c *concrete) Login(string, string) (smtp.User, error) {
-	return nil, nil
+func (c *concrete) Login(user, pass string) (smtp.User, error) {
+	// FIXME: TODO: Check for account existence and correct password(!)
+	session := &Session{
+		ID:          atomic.AddUint64(&c.sid, uint64(1)),
+		AccountName: user,
+		ServiceName: c.name,
+	}
+
+	log.Printf("Beginning %s session %d for %s", c.name, session.ID, user)
+
+	return session, nil
 }
 
 func (c *concrete) Close() error {
diff --git a/internal/smtp/session.go b/internal/smtp/session.go
new file mode 100644
index 0000000..a4989cb
--- /dev/null
+++ b/internal/smtp/session.go
@@ -0,0 +1,32 @@
+package smtp
+
+import (
+	"fmt"
+	"io"
+	"io/ioutil"
+	"log"
+)
+
+// type Session implements the User interface for emersion/go-smtp
+type Session struct {
+	ID          uint64
+	AccountName string
+	ServiceName string
+}
+
+func (s *Session) Send(from string, to []string, r io.Reader) error {
+	data, err := ioutil.ReadAll(r)
+	if err != nil {
+		return err
+	}
+
+	log.Printf("%s session %d for %s: from=%s, to=%s, r=<<EOF\n%s\nEOF", s.ServiceName, s.ID, s.AccountName, from, to, string(data))
+
+	return fmt.Errorf("Not yet implemented")
+}
+
+func (s *Session) Logout() error {
+	log.Printf("Ending %s session %d for %s", s.ServiceName, s.ID, s.AccountName)
+
+	return nil
+}
diff --git a/internal/store/store.go b/internal/store/store.go
index 06de5bd..5ad35ed 100644
--- a/internal/store/store.go
+++ b/internal/store/store.go
@@ -68,8 +68,8 @@ type concrete struct {
 	storm        *storm.DB
 	domainBucket storm.Node
 
-	// These are persisted in BoltDB, but we
-	// Might as well keep them in memory for the duration, though.
+	// These are persisted in BoltDB, but we might as well keep them in memory
+	// for the duration. Calls to SetDomain/SetTLS will invalidate them.
 	domain string
 	cert   tls.Certificate
 }