move parsing of !pm send to utils, update !pm send instructions

utils/command.go

@@ -0,0 +1,25 @@
+package utils
+
+import (
+	"fmt"
+	"strings"
+)
+
+// ErrInvalidArgs returned when a command's arguments are invalid
+var ErrInvalidArgs = fmt.Errorf("invalid arguments")
+
+// ParseSend parses "!pm send" command, returns to, subject, body, err
+func ParseSend(commandSlice []string) (string, string, string, error) {
+	if len(commandSlice) < 3 {
+		return "", "", "", ErrInvalidArgs
+	}
+
+	message := strings.Join(commandSlice, " ")
+	lines := strings.Split(message, "\n")
+	commandSlice = strings.Split(lines[0], " ")
+	to := commandSlice[1]
+	subject := lines[1]
+	body := strings.Join(lines[2:], "\n")
+
+	return to, subject, body, nil
+}