#define VERSION "1.0"
#define AUTHOR "DukePyrolator"  
	/* Jens 'DukePyrolator' Voss  <DukePyrolator@FantasyIRC.net */
#include "module.h"
#include "datafiles.h"

#define HELP_SYNTAX "Syntax: \002LINK \037ADD\037|\037DEL\037|\037LIST\037 [\037#chan1\037] [\037#chan2\037]\002"



/*
    known bugs:     cs ist not free'd after module unloading (memleak)
*/

/* dont change it ! */
#define CL_VERSION 1
#define HASH(nick)   ((tolower((nick)[0])&31)<<5 | (tolower((nick)[1])&31))

typedef struct chanlink_ ChanLink;
struct chanlink_ {
    ChanLink *next, *prev;
    char *chan, *newchan;
    uint32 flags;
};

ChanLink *clists[1024];

int cs_link(User *u);
int do_on_join(char *source, int ac, char **av);

/* database functions */
void load_cl_db(void);
void save_cl_db(void);
int del_cl(ChanLink *cl);
ChanLink *make_cl(char *chan);
ChanLink *find_cl(char *chan);
void insert_cl(ChanLink * cl);

char *ChanLinkDB = "ChanLink.db";


/*************************************************************************************/
int AnopeInit(int argc, char **argv) {
    Command *c;
    Message *m;

    c = createCommand("LINK", cs_link, is_services_admin, -1, -1, -1 , -1, -1);
    moduleAddCommand(CHANSERV, c, MOD_UNIQUE);

    if (UseTokens) 
        m = createMessage("~", do_on_join); /* sjoin */
    else
	m = createMessage("SJOIN", do_on_join); /* sjoin */
    moduleAddMessage(m, MOD_HEAD);

    moduleAddAuthor(AUTHOR);
    moduleAddVersion(VERSION);
    load_cl_db();
    return MOD_CONT;
}

/******************************************************************/

void AnopeFini(void) {
    save_cl_db();
}

/******************************************************************/
int cs_link(User *u) {
    ChanLink *cl;
    char *temp = moduleGetLastBuffer();
    char *cmd = myStrGetToken(temp,' ',0);
    char *option1 = myStrGetToken(temp,' ',1);
    char *option2 = myStrGetTokenRemainder(temp,' ',2);
    int i = 0, j = 0;


    if (!cmd) {
	notice_user(s_ChanServ, u, HELP_SYNTAX);
	goto MODCONT;
    }
    
    if (!stricmp("ADD",cmd)) {
	if (!option2) {
    	    notice_user(s_ChanServ, u, HELP_SYNTAX);
    	    goto MODCONT;
	}
	if (!(cl = find_cl(option1))) {
		cl = make_cl(option1);
	}
	if (cl->newchan) 
		free(cl->newchan);
	cl->newchan = sstrdup(option2);
	save_cl_db();
	notice_user(s_ChanServ, u, "New Link added");
    	goto MODCONT;
    }
    if (!stricmp("DEL",cmd)) {
	if (!option1) {
	    notice_user(s_ChanServ, u, HELP_SYNTAX);
	    goto MODCONT;
	}
	if (cl = find_cl(option1)) {
	    del_cl(cl);    
	    save_cl_db();
	    notice_user(s_ChanServ, u, "Link for chan %s removed", option1);
	    goto MODCONT;
	}
	notice_user(s_ChanServ, u, "no link for this chan");
	goto MODCONT;
    }
    if (!stricmp("LIST", cmd)) {
	notice_user(s_ChanServ, u, "Linked Channels:");
        for (i = 0; i < 1024; i++) {
    	    for (cl = clists[i]; cl; cl = cl->next) {
		j++;
		notice_user(s_ChanServ, u, " %i. %s -> %s", j, cl->chan, cl->newchan);
	    }
	}
	goto MODCONT;
    }
    notice_user(s_ChanServ, u, HELP_SYNTAX);

    MODCONT:
    if (cmd) free(cmd);
    if (option1) free(option1);
    if (option2) free(option2);
    return MOD_CONT;
}

/******************************************************************/

int do_on_join(char *source, int ac, char **av) {
    User *u;
    ChanLink *cl;
    char *buf;

    if (ac == 3) {
	buf = sstrdup(av[2]);
	if (buf[0] == '@') buf++;  
    	u = finduser(buf);
	free(buf);
    } else return MOD_CONT;

    if (cl = find_cl(av[1])) {
	send_cmd(NULL, "SVSPART %s %s %s", u->nick, av[1], "...");
	send_cmd(NULL, "SVSJOIN %s %s", u->nick, cl->newchan);
	return MOD_STOP;
    }

    return MOD_CONT;
}

/******************************************************************/

void insert_cl(ChanLink * cl)
{
    int index = HASH(cl->chan);

    cl->prev = NULL;
    cl->next = clists[index];
    if (cl->next)
        cl->next->prev = cl;
    clists[index] = cl;
}

/*******************************************************************/

ChanLink *find_cl(char *chan)
{
    ChanLink *cl;

    if (!chan)
        return NULL;
    for (cl = clists[HASH(chan)]; cl; cl = cl->next) {
        if (!stricmp(cl->chan, chan))
            return cl;
    }
    return NULL;
}

/*******************************************************************/

ChanLink *make_cl(char *chan)
{
    ChanLink *cl;

    cl = scalloc(sizeof(ChanLink), 1);
    cl->chan = sstrdup(chan);
    cl->newchan = NULL;
    cl->flags = 0;
    insert_cl(cl);
    return cl;
}

/*************************************************************************/

int del_cl(ChanLink *cl)
{
    if (cl) {
        clists[HASH(cl->chan)] = cl->next;
        if (cl->chan)
            free(cl->chan);
	if (cl->newchan)
	    free(cl->newchan);
        free(cl);
    }
    return 0;
}

/*************************************************************************/

#define SAFE(x) do {                                            \
    if ((x) < 0) {                                              \
        restore_db(f);                                          \
        log_perror("Write error on %s", ChanLinkDB);                \
        if (time(NULL) - lastwarn > WarningTimeout) {           \
            anope_cmd_global(NULL, "Write error on %s: %s", ChanLinkDB, \
                        strerror(errno));                       \
            lastwarn = time(NULL);                              \
        }                                                       \
        return;                                                 \
    }                                                           \
} while (0)

void save_cl_db(void)
{
    dbFILE *f;
    int i;
    ChanLink *cl;
    static time_t lastwarn = 0;

    if (!(f = open_db("cs_link", ChanLinkDB, "w", CL_VERSION)))
        return;

    for (i = 0; i < 1024; i++) {
        for (cl = clists[i]; cl; cl = cl->next) {
            SAFE(write_int8(1, f));
            SAFE(write_string(cl->chan, f));
	    SAFE(write_string(cl->newchan, f));
            SAFE(write_int32(cl->flags, f));
            SAFE(write_int8(0, f));
        }
    }
    close_db(f);

}

#undef SAFE


/******************************************************************/

#define SAFE(x) do {                                    \
    if ((x) < 0) {                                      \
    fatal("Read error on %s", ChanLinkDB);              \
        failed = 1;                                     \
        break;                                          \
    }                                                   \
} while (0)

void load_cl_db(void)
{
    dbFILE *f;
    int i, c, ver;
    ChanLink *cl;
    int failed = 0;
    char *s;

    if (!(f = open_db("cs_link", ChanLinkDB, "r", CL_VERSION)))
        return;
    ver = get_file_version(f);
    for (i = 0; i < 1024 && !failed; i++) {
        while ((c = getc_db(f)) == 1) {
            if (c != 1)
                fatal("Invalid format in %s", ChanLinkDB);

            SAFE(read_string(&s, f));
            cl = make_cl(s);
            free(s);
	    SAFE(read_string(&cl->newchan, f));
            SAFE(read_int32(&cl->flags, f));
        }
    }
    close_db(f);
}

#undef SAFE

/********************************************************************/
/*                     end of file                                  */ 
/********************************************************************/