--- a/src/imap/ngx_imap.h
+++ b/src/imap/ngx_imap.h
@@ -4,40 +4,63 @@
 
 #include <ngx_config.h>
 #include <ngx_core.h>
+#include <ngx_event.h>
+#include <ngx_event_connect.h>
 
 
 typedef struct {
-    ngx_connection_t      *connection;
+    ngx_peer_connection_t   upstream;
 
-    ngx_buf_t             *downstream_buffer;
-    ngx_buf_t             *upstream_buffer;
+    ngx_buf_t              *buffer;
 } ngx_imap_proxy_ctx_t;
 
 
 typedef struct {
-    uint32_t               signature;         /* "IMAP" */
+    uint32_t                signature;         /* "IMAP" */
+
+    ngx_connection_t       *connection;
+    ngx_buf_t              *buffer;
+
+    ngx_imap_proxy_ctx_t   *proxy;
 
-    ngx_connection_t      *connection;
-    ngx_imap_proxy_ctx_t  *proxy;
+    ngx_uint_t              command;
+    ngx_array_t             args;
+
+    /* used to parse IMAP/POP3 command */
+
+    ngx_uint_t              state;
+    u_char                 *arg_start;
+    u_char                 *arg_end;
 } ngx_imap_session_t;
 
 
-#define NGX_POP3_USER      1
-#define NGX_POP3_PASS      2
-#define NGX_POP3_APOP      3
-#define NGX_POP3_STAT      4
-#define NGX_POP3_LIST      5
-#define NGX_POP3_RETR      6
-#define NGX_POP3_DELE      7
-#define NGX_POP3_NOOP      8
-#define NGX_POP3_RSET      9
-#define NGX_POP3_TOP       10
-#define NGX_POP3_UIDL      11
-#define NGX_POP3_QUIT      12
+#define NGX_POP3_USER       1
+#define NGX_POP3_PASS       2
+#define NGX_POP3_APOP       3
+#define NGX_POP3_STAT       4
+#define NGX_POP3_LIST       5
+#define NGX_POP3_RETR       6
+#define NGX_POP3_DELE       7
+#define NGX_POP3_NOOP       8
+#define NGX_POP3_RSET       9
+#define NGX_POP3_TOP        10
+#define NGX_POP3_UIDL       11
+#define NGX_POP3_QUIT       12
+
+
+#define NGX_IMAP_PARSE_INVALID_COMMAND  10
+
+
+#define NGX_IMAP_PROXY_INVALID  10
+#define NGX_IMAP_PROXY_ERROR    11
 
 
 void ngx_imap_init_connection(ngx_connection_t *c);
 void ngx_imap_close_connection(ngx_connection_t *c);
 
+void ngx_imap_proxy_init(ngx_imap_session_t *s);
+
+ngx_int_t ngx_pop3_parse_command(ngx_imap_session_t *s);
+
 
 #endif /* _NGX_IMAP_H_INCLUDED_ */