#include "jim.h"
#include "jimautoconf.h"
#include <string.h>

/* -----------------------------------------------------------------------------
 * Dynamic libraries support (WIN32 not supported)
 * ---------------------------------------------------------------------------*/

#if defined(HAVE_DLOPEN) || defined(HAVE_DLOPEN_COMPAT)

#ifdef HAVE_DLFCN_H
#include <dlfcn.h>
#endif

/**
 * Note that Jim_LoadLibrary() requires a path to an existing file.
 * 
 * If it is necessary to search JIM_LIBPATH, use Jim_PackageRequire() instead.
 */
int Jim_LoadLibrary(Jim_Interp *interp, const char *pathName)
{
    void *handle = dlopen(pathName, RTLD_LAZY);
    if (handle == NULL) {
        Jim_SetResultFormatted(interp, "error loading extension \"%s\": %s", pathName,
            dlerror());
    }
    else {
        /* We use a unique init symbol depending on the extension name.
         * This is done for compatibility between static and dynamic extensions.
         * For extension readline.so, the init symbol is "Jim_readlineInit"
         */
        const char *pt;
        const char *pkgname;
        int pkgnamelen;
        char initsym[40];
        int (*onload) (Jim_Interp *);

        pt = strrchr(pathName, '/');
        if (pt) {
            pkgname = pt + 1;
        }
        else {
            pkgname = pathName;
        }
        pt = strchr(pkgname, '.');
        if (pt) {
            pkgnamelen = pt - pkgname;
        }
        else {
            pkgnamelen = strlen(pkgname);
        }
        snprintf(initsym, sizeof(initsym), "Jim_%.*sInit", pkgnamelen, pkgname);

        if ((onload = dlsym(handle, initsym)) == NULL) {
            Jim_SetResultFormatted(interp,
                "No %s symbol found in extension %s", initsym, pathName);
        }
        else if (onload(interp) != JIM_ERR) {
            Jim_SetEmptyResult(interp);
            return JIM_OK;
        }
    }
    if (handle) {
        dlclose(handle);
    }
    return JIM_ERR;
}
#else /* JIM_DYNLIB */
int Jim_LoadLibrary(Jim_Interp *interp, const char *pathName)
{
    JIM_NOTUSED(interp);
    JIM_NOTUSED(pathName);

    Jim_SetResultString(interp, "the Jim binary has no support for [load]", -1);
    return JIM_ERR;
}
#endif /* JIM_DYNLIB */

/* [load] */
static int Jim_LoadCoreCommand(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
{
    if (argc < 2) {
        Jim_WrongNumArgs(interp, 1, argv, "libaryFile");
        return JIM_ERR;
    }
    return Jim_LoadLibrary(interp, Jim_GetString(argv[1], NULL));
}

int Jim_loadInit(Jim_Interp *interp)
{
    Jim_CreateCommand(interp, "load", Jim_LoadCoreCommand, NULL, NULL);
    return JIM_OK;
}