/* This file is part of the Zebra server.
   Copyright (C) Index Data

Zebra is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.

Zebra is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

*/


#if HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <assert.h>
#include <string.h>
#if HAVE_DLFCN_H
#include <dlfcn.h>
#endif

#include <direntz.h>
#include <yaz/snprintf.h>
#include <idzebra/util.h>
#include <idzebra/recctrl.h>

struct recTypeClass {
    RecType recType;
    struct recTypeClass *next;
    void *module_handle;
};

struct recTypeInstance {
    RecType recType;
    struct recTypeInstance *next;
    int init_flag;
    void *clientData;
};

struct recTypes {
    data1_handle dh;
    struct recTypeInstance *entries;
};

static void recTypeClass_add (struct recTypeClass **rts, RecType *rt,
                              NMEM nmem, void *module_handle);


RecTypeClass recTypeClass_create (Res res, NMEM nmem)
{
    struct recTypeClass *rts = 0;

#if IDZEBRA_STATIC_GRS_SGML
    if (1)
    {
        extern RecType idzebra_filter_grs_sgml[];
        recTypeClass_add (&rts, idzebra_filter_grs_sgml, nmem, 0);
    }
#endif

#if IDZEBRA_STATIC_TEXT
    if (1)
    {
        extern RecType idzebra_filter_text[];
        recTypeClass_add (&rts, idzebra_filter_text, nmem, 0);
    }
#endif

#if IDZEBRA_STATIC_GRS_XML
#if HAVE_EXPAT_H
    if (1)
    {
        extern RecType idzebra_filter_grs_xml[];
        recTypeClass_add (&rts, idzebra_filter_grs_xml, nmem, 0);
    }
#endif
#endif

#if IDZEBRA_STATIC_GRS_REGX
    if (1)
    {
        extern RecType idzebra_filter_grs_regx[];
        recTypeClass_add (&rts, idzebra_filter_grs_regx, nmem, 0);
    }
#endif

#if IDZEBRA_STATIC_GRS_MARC
    if (1)
    {
        extern RecType idzebra_filter_grs_marc[];
        recTypeClass_add (&rts, idzebra_filter_grs_marc, nmem, 0);
    }
#endif

#if IDZEBRA_STATIC_SAFARI
    if (1)
    {
        extern RecType idzebra_filter_safari[];
        recTypeClass_add (&rts, idzebra_filter_safari, nmem, 0);
    }
#endif

#if IDZEBRA_STATIC_ALVIS
    if (1)
    {
        extern RecType idzebra_filter_alvis[];
        recTypeClass_add (&rts, idzebra_filter_alvis, nmem, 0);
    }
#endif

#if IDZEBRA_STATIC_DOM
    if (1)
    {
        extern RecType idzebra_filter_dom[];
        recTypeClass_add (&rts, idzebra_filter_dom, nmem, 0);
    }
#endif

    return rts;
}

static void load_from_dir(RecTypeClass *rts, NMEM nmem, const char *dirname)
{
#if HAVE_DLFCN_H
    DIR *dir = opendir(dirname);
    if (dir)
    {
        struct dirent *de;

        while ((de = readdir(dir)))
        {
            size_t dlen = strlen(de->d_name);
            if (dlen >= 5 &&
                !memcmp(de->d_name, "mod-", 4) &&
                !strcmp(de->d_name + dlen - 3, ".so"))
            {
                void *mod_p, *fl;
                char fname[FILENAME_MAX*2+1];
                yaz_snprintf(fname, sizeof(fname), "%s/%s",
                        dirname, de->d_name);
                mod_p = dlopen(fname, RTLD_NOW|RTLD_GLOBAL);
                if (mod_p && (fl = dlsym(mod_p, "idzebra_filter")))
                {
                    yaz_log(YLOG_LOG, "Loaded filter module %s", fname);
                    recTypeClass_add(rts, fl, nmem, mod_p);
                }
                else if (mod_p)
                {
                    const char *err = dlerror();
                    yaz_log(YLOG_WARN, "dlsym failed %s %s",
                            fname, err ? err : "none");
                    dlclose(mod_p);
                }
                else
                {
                    const char *err = dlerror();
                    yaz_log(YLOG_WARN, "dlopen failed %s %s",
                            fname, err ? err : "none");

                }
            }
        }
        closedir(dir);
    }
#endif
}

void recTypeClass_load_modules(RecTypeClass *rts, NMEM nmem,
                               const char *module_path)
{
    while (module_path)
    {
        const char *comp_ptr;
        char comp[FILENAME_MAX+1];
        size_t len;

        len = yaz_filepath_comp(&module_path, &comp_ptr);
        if (!len || len >= FILENAME_MAX)
            break;

        memcpy(comp, comp_ptr, len);
        comp[len] = '\0';

        load_from_dir(rts, nmem, comp);
    }
}

static void recTypeClass_add(struct recTypeClass **rts, RecType *rt,
                             NMEM nmem, void *module_handle)
{
    while (*rt)
    {
        struct recTypeClass *r = (struct recTypeClass *)
            nmem_malloc (nmem, sizeof(*r));

        r->next = *rts;
        *rts = r;

        r->module_handle = module_handle;
        module_handle = 0; /* so that we only store module_handle once */
        r->recType = *rt;

        rt++;
    }
}

void recTypeClass_info(RecTypeClass rtc, void *cd,
                       void (*cb)(void *cd, const char *s))
{
    for (; rtc; rtc = rtc->next)
        (*cb)(cd, rtc->recType->name);
}

void recTypeClass_destroy(RecTypeClass rtc)
{
    for (; rtc; rtc = rtc->next)
    {
#if HAVE_DLFCN_H
        if (rtc->module_handle)
            dlclose(rtc->module_handle);
#endif
    }
}

RecTypes recTypes_init(RecTypeClass rtc, data1_handle dh)
{
    RecTypes rts = (RecTypes) nmem_malloc(data1_nmem_get(dh), sizeof(*rts));

    struct recTypeInstance **rti = &rts->entries;

    rts->dh = dh;

    for (; rtc; rtc = rtc->next)
    {
        *rti = nmem_malloc(data1_nmem_get(dh), sizeof(**rti));
        (*rti)->recType = rtc->recType;
        (*rti)->init_flag = 0;
        rti = &(*rti)->next;
    }
    *rti = 0;
    return rts;
}

void recTypes_destroy (RecTypes rts)
{
    struct recTypeInstance *rti;

    for (rti = rts->entries; rti; rti = rti->next)
    {
        if (rti->init_flag)
            (*(rti->recType)->destroy)(rti->clientData);
    }
}

RecType recType_byName (RecTypes rts, Res res, const char *name,
                        void **clientDataP)
{
    struct recTypeInstance *rti;

    for (rti = rts->entries; rti; rti = rti->next)
    {
        size_t slen = strlen(rti->recType->name);
        if (!strncmp (rti->recType->name, name, slen)
            && (name[slen] == '\0' || name[slen] == '.'))
        {
            if (!rti->init_flag)
            {
                rti->init_flag = 1;
                rti->clientData =
                    (*(rti->recType)->init)(res, rti->recType);
            }
            *clientDataP = rti->clientData;
            if (name[slen])
                slen++;  /* skip . */

            if (rti->recType->config)
            {
                if ((*(rti->recType)->config)
                    (rti->clientData, res, name+slen) != ZEBRA_OK)
                    return 0;
            }
            return rti->recType;
        }
    }
    return 0;
}

/*
 * Local variables:
 * c-basic-offset: 4
 * c-file-style: "Stroustrup"
 * indent-tabs-mode: nil
 * End:
 * vim: shiftwidth=4 tabstop=8 expandtab
 */