/* Copyright (c) 2015-2017, Michael Santos <michael.santos@gmail.com>
 *
 * Permission to use, copy, modify, and/or 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <ctype.h>
#include <limits.h>
#include <err.h>
#include <sys/types.h>

#include <strophe.h>

#define XMPPIPE_VERSION "0.12.0"
#define XMPPIPE_RESOURCE "xmppipe"

#define XMPPIPE_STREQ(a,b)      (strcmp((a),(b)) == 0)
#define XMPPIPE_STRNEQ(a,b)     (strcmp((a),(b)) != 0)

#define BASE64_LENGTH(n)        ((((n) + 2) / 3) * 4)

enum {
    XMPPIPE_S_DISCONNECTED,
    XMPPIPE_S_CONNECTING,
    XMPPIPE_S_CONNECTED,

    XMPPIPE_S_MUC_SERVICE_LOOKUP,
    XMPPIPE_S_MUC_FEATURE_LOOKUP,
    XMPPIPE_S_MUC_WAITJOIN,
    XMPPIPE_S_MUC_JOIN,
    XMPPIPE_S_MUC_UNLOCK,

    XMPPIPE_S_READY,
    XMPPIPE_S_READY_AVAIL,
    XMPPIPE_S_READY_EMPTY,
};

enum {
    XMPPIPE_OPT_DISCARD = 1 << 0,           /* Throw away stdin if no occupants in MUC */
    XMPPIPE_OPT_DISCARD_TO_STDOUT = 1 << 1, /* Throw away stdin and send to local stdout */
    XMPPIPE_OPT_EOF = 1 << 2,               /* Keep running on stdin EOF */
    XMPPIPE_OPT_SIGPIPE = 1 << 3,           /* Exit if no occupants in MUC */
    XMPPIPE_OPT_GROUPCHAT = 1 << 4,         /* Use groupchat */
    XMPPIPE_OPT_CHAT_MARKER = 1 << 5,       /* Display chat markers */
};

enum {
    XMPPIPE_FMT_TEXT = 0,
    XMPPIPE_FMT_CSV
};

typedef struct {
    xmpp_ctx_t *ctx;
    xmpp_conn_t *conn;
    int handled;

    char *room;         /* room, room@conference.xmpp.example.com */
    char *server;       /* xmpp.example.com */
    char *resource;     /* nick */
    char *mucservice;   /* conference.xmpp.example.com */
    char *mucjid;       /* room@conference.xmpp.example.com/nick */
    char *subject;      /* topic/subject for MUC */
    char *out;          /* room@conference.xmpp.example.com */

    int status;
    int occupants;
    u_int32_t poll;     /* milliseconds */
    u_int32_t keepalive; /* periodically send a keepalive (milliseconds) */
    u_int32_t keepalive_fail;  /* number of consecutive keepalives without a reply */
    u_int32_t keepalive_limit; /* number of keepalives without a reply */
    u_int32_t interval; /* time since last keepalive (milliseconds) */
    size_t bufsz;       /* size of read buffer */

    int sm_enabled;     /* stanzas: iq, message, presence */

    u_int32_t sm_request; /* count of sent stanzas */
    u_int32_t sm_request_unack; /* count of unacknowledged stream management requests */
    u_int32_t sm_request_interval; /* request ack every interval stanzas */

    u_int32_t sm_ack_recv;  /* count of stanzas received from server */
    u_int32_t sm_ack_sent;  /* server's count of stanzas we've sent */

    u_int32_t sm_unacked;
    u_int32_t sm_fc;

    int opt;
    int verbose;
    int encode;         /* base64 encode/decode data to MUC */
    int format;         /* input format: stdin, colon */
} xmppipe_state_t;

/* handlers */
int handle_message(xmpp_conn_t * const, xmpp_stanza_t * const, void * const);
int handle_null(xmpp_conn_t * const, xmpp_stanza_t * const, void * const);
int handle_ping_reply(xmpp_conn_t * const, xmpp_stanza_t * const, void * const);
int handle_version(xmpp_conn_t * const, xmpp_stanza_t * const, void * const);

void xmppipe_send_stanza(xmppipe_state_t *, char *, size_t);
void xmppipe_send_stanza_fmt(xmppipe_state_t *state, char *buf, size_t len);
void xmppipe_send_message(xmppipe_state_t *, char *, char *, char *, size_t);
void xmppipe_send(xmppipe_state_t *, xmpp_stanza_t *const);

int xmppipe_fmt_init();
char *xmppipe_fmt_encode(const char *);
char *xmppipe_nfmt_encode(const char *, size_t);
char *xmppipe_fmt_decode(const char *);
char *xmppipe_nfmt_decode(const char *, size_t);
int xmppipe_set_nonblock(int fd);

char *xmppipe_servername(char *);
char *xmppipe_roomname(char *);
char *xmppipe_conference(char *, char *);
char *xmppipe_mucjid(char *, char *);

char *xmppipe_getenv(const char *);
char *xmppipe_strdup(const char *);
void *xmppipe_malloc(size_t);
void *xmppipe_calloc(size_t, size_t);
char *xmppipe_strtok(char *str, char const *delims);

xmpp_stanza_t *xmppipe_stanza_new(xmpp_ctx_t *);
void xmppipe_stanza_set_attribute(xmpp_stanza_t * const, const char * const,
        const char * const);
void xmppipe_stanza_set_id(xmpp_stanza_t * const, const char * const);
void xmppipe_stanza_set_name(xmpp_stanza_t *, const char * const);
void xmppipe_stanza_set_ns(xmpp_stanza_t * const, const char * const);
void xmppipe_stanza_set_text(xmpp_stanza_t *, const char * const);
void xmppipe_stanza_set_type(xmpp_stanza_t * const, const char * const);
void xmppipe_stanza_add_child(xmpp_stanza_t *, xmpp_stanza_t *);

int xmppipe_sandbox_init(xmppipe_state_t *state);
int xmppipe_sandbox_stdin(xmppipe_state_t *state);
int xmppipe_conn_fd(xmppipe_state_t *state);

int b64_ntop(u_char const *src, size_t srclength, char *target,
        size_t targsize);
int b64_pton(char const *src, u_char *target, size_t targsize);

#ifndef HAVE_STRTONUM
long long strtonum(const char *numstr, long long minval, long long maxval,
        const char **errstrp);
#endif