/*

 * Copyright (c) 2014 Sunil Nimmagadda <sunil@nimmagadda.net>

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

#include <sys/tree.h>

#include <sha1.h>

#include "imsgev.h"

#include "iobuf.h"

#include "ioev.h"

#define	ARGLEN		40

#define POP3S		0x01

#define	F_DELE		0x01

struct passwd;

enum imsg_type {

	IMSG_AUTH,

	IMSG_MAILDROP_INIT,

	IMSG_MAILDROP_RETR,

	IMSG_MAILDROP_DELE,

	IMSG_MAILDROP_RSET,

	IMSG_MAILDROP_LIST,

	IMSG_MAILDROP_LISTALL,

	IMSG_MAILDROP_UPDATE

};

enum m_type {

	M_MBOX,

	M_MAILDIR

};

struct msg {

	union {

		SIMPLEQ_ENTRY(msg)	q_entry;

		RB_ENTRY(msg)		t_entry;

	}				e;

	char				hash[SHA1_DIGEST_STRING_LENGTH];

	size_t				sz;

	size_t				nlines;

	union {

		long			offset;

		const char		*fname;

	}				u;

	int				flags;

};

struct mdrop {

	union {

		SIMPLEQ_HEAD(, msg)	q_msgs;

		RB_HEAD(msgtree, msg)	t_msgs;

	}				e;

	size_t				nmsgs;

	size_t				sz;

	struct msg			**msgs_index; /* random access msgs */

	int				fd;

};

struct stats {

	size_t	nmsgs;

	size_t	sz;

};

struct retr_req {

	unsigned int	idx;

	unsigned int	ntop;

	int		top;

};

struct retr_res {

	size_t		nlines;

	long		offset;

	unsigned int	ntop;

	int		top;

};

struct list_req {

	unsigned int	idx;

	int		uidl;

};

struct list_res {

	unsigned int	idx;

	union {

		size_t	sz;

		char	hash[SHA1_DIGEST_STRING_LENGTH];

	}		u;

	int		uidl;

};

struct m_backend {

	int (*init)(struct mdrop *, size_t *, size_t *);

	int (*retr)(struct mdrop *, unsigned int, size_t *, long *);

	int (*update)(struct mdrop *);

};

struct auth_req {

	char	user[ARGLEN];

	char	pass[ARGLEN];

};

struct listener {

	struct event		ev;

	struct event		pause;

	int			flags;

	int			sock;

};

enum state {

	AUTH,

	TRANSACTION,

	UPDATE

};

struct session {

	SPLAY_ENTRY(session)	entry;

	struct iobuf		iobuf;

	struct io		io;

	struct sockaddr_storage	ss;

	char			user[ARGLEN];

	char			pass[ARGLEN];

	size_t			m_sz;

	size_t			nmsgs;

	struct listener		*l;

	struct imsgev		*iev_maildrop;

	uint32_t		id;

	int			flags;

	enum state		state;

};

/* pop3e.c */

void pop3_main(int [2], struct passwd *, const char *, const char *);

/* session.c */

void session_init(struct listener *, int, const struct sockaddr_storage *);

void session_close(struct session *, int);

void session_reply(struct session *, char *, ...);

void session_set_state(struct session *, enum state);

void session_imsgev_init(struct session *, int);

SPLAY_HEAD(session_tree, session);

int session_cmp(struct session *, struct session *);

SPLAY_PROTOTYPE(session_tree, session, entry, session_cmp);

/* maildrop.c */

pid_t maildrop_setup(uint32_t, int [2], struct passwd *);

/* util.c */

void set_nonblocking(int);

void log_init(int);

void logit(int, const char *, ...);

void vlog(int, const char *, va_list);

void fatal(const char *);

void fatalx(const char *);

void *xcalloc(size_t, size_t, const char *);

void iobuf_xfqueue(struct iobuf *, const char *, const char *, ...);

void iobuf_xqueue(struct iobuf *, const char *, const void *, size_t);

int imsgev_xcompose(struct imsgev *, u_int16_t, u_int32_t,

    uint32_t, int, void *, u_int16_t, const char *);

int get_index(struct session *, const char *, unsigned int *);

void log_connect(uint32_t, struct sockaddr_storage *, socklen_t);