First version to show (raw) email bodies.

Made xwebmail work with new handlers package.
Pulls important headers from the database and provides extremely basic folder
view on webpage.
Reverted layout customizations returning folder view to original wider width.
JS App now handles all the rendering, index.html only contains placeholder
with background to indicate loading.

db/util.go

@@ -42,7 +42,7 @@ type Original struct {
 }
 
 func (c *Conn) Originals(oCh chan<- Original, errc chan<- error, donec <-chan struct{}) {
-	query := `
+	const query = `
 SELECT
 	uid,
 	hash,
@@ -224,7 +224,7 @@ VALUES
 	return nil
 }
 
-var MagicAllLabel = "[all]"
+const MagicAllLabel = "[all]"
 
 type Paginator struct {
 	Label  string
@@ -232,11 +232,84 @@ type Paginator struct {
 	Count  int
 }
 
+type Address mail.Address
+
+type MessageHeader struct {
+	Hash    string
+	From    *Address
+	To      []*Address
+	Cc      []*Address
+	Subject string
+	Date    time.Time
+	Seen    bool
+	// TODO
+	Summary, ListId string
+}
+
 // Index returns ranges of metadata for messages as defined by paginator.
-func (c *Conn) Index(p *Paginator) error {
+func (c *Conn) Index(p *Paginator) ([]*MessageHeader, error) {
+	const query = `
+SELECT
+    hash, name, value
+FROM
+    search_header
+WHERE
+    name IN ('Date', 'Subject', 'To', 'From', 'Cc')
+ORDER BY
+    hash
+LIMIT
+    100
+-- TODO add offset based on Paginator
+;
+`
+	var res []*MessageHeader
 	if p.Label == MagicAllLabel {
 		// Paginate all messages.
 	}
+
 	// Else, filter by label.
-	return nil
+	rows, err := c.Query(query)
+	if err != nil {
+		return res, err
+	}
+	var mh *MessageHeader
+	for rows.Next() {
+		var hash, name, value string
+		if err := rows.Scan(&hash, &name, &value); err != nil {
+			return res, err
+		}
+		if mh == nil {
+			// First Row
+			mh = new(MessageHeader)
+			mh.Hash = hash
+		}
+
+		if hash != mh.Hash {
+			res = append(res, mh)
+			mh = new(MessageHeader)
+			mh.Hash = hash
+		}
+		switch name {
+		case "Date":
+			t, err := time.Parse(time.RFC3339Nano, value)
+			if err != nil {
+				return res, err
+			}
+			mh.Date = t
+		case "Subject":
+			mh.Subject = value
+		case "To":
+			mh.To = append(mh.To, &Address{Address: value})
+		case "From":
+			mh.From = &Address{Address: value}
+		case "Cc":
+			mh.Cc = append(mh.Cc, &Address{Address: value})
+		}
+	}
+	// Intentionally don't handle the last MessageHeader, it is likely
+	// incomplete if LIMIT in the query cuts off a message midstream.
+	if err := rows.Err(); err != nil {
+		return res, err
+	}
+	return res, nil
 }