/**********
Copyright 1991 Regents of the University of California.  All rights reserved.
**********/

#include "ngspice/ngspice.h"
#include "ivars.h"
#include "../misc/util.h" /* ngdirname() */

char *Spice_Path;
char *News_File;
char *Help_Path;
char *Lib_Path;
char *Inp_Path;
char *Spice_Exec_Path;


static void
env_overr(char **v, char *e)
{
    char *p;
    if (v && e && (p = getenv(e)) != NULL)
        *v = p;
}

static void
mkvar(char **p, char *path_prefix, char *var_dir, char *env_var)
{
    /* Override by environment variables */
    char *buffer = getenv(env_var);

    if (buffer)
        *p = tprintf("%s",buffer);
    else
        *p = tprintf("%s%s%s", path_prefix, DIR_PATHSEP, var_dir);
}

    /* $dprefix has been set to /usr/local or C:/Spice (Windows) in configure.ac,
    or to <path> given by prefix="<path>" as parameter to ./configure command.
    NGSPICEBINDIR has been set to $dprefix/bin in config.h.
    NGSPICEDATADIR has been set to $dprefix/share/ngspice in config.h.
    If --enable-relpath is selected as paramter to the ./configure command, then
    NGSPICEBINDIR is set to ../bin in config.h.
    NGSPICEDATADIR is set to ../share/ngspice in config.h.
    Spice_Exec_Dir has been set to NGSPICEBINDIR in conf.c,
    may be overridden here by environmental variable SPICE_EXEC_DIR.
    Spice_Lib_Dir has been set to NGSPICEDATADIR in conf.c,
    may be overridden here by environmental variable SPICE_LIB_DIR.
    The search path for codemodels in spinit contains $dprefix, or, if --enable-relpath
    is given, to ../lib, set by src/makefile.am. With Visual C, it is set manually by
    an entry to ngspice\visualc\src\include\ngspice\config.h.
    For Windows GUI and Console the path is set relative to the executable.*/
void
ivars(char *argv0)
{
    char *temp=NULL;
#if defined (HAS_WINGUI) || defined (__MINGW32__) || defined (_MSC_VER)
    char *ngpath;
#endif

#ifdef HAS_RELPATH
    Spice_Lib_Dir = temp = copy("../share/ngspice");
#elif !defined SHARED_MODULE && (defined (HAS_WINGUI) || defined (__MINGW32__) || defined (_MSC_VER))
    ngpath = ngdirname(argv0);
    mkvar(&Spice_Lib_Dir, ngpath, "../share/ngspice", "SPICE_LIB_DIR");
    tfree(ngpath);
#else
    env_overr(&Spice_Lib_Dir, "SPICE_LIB_DIR");
#endif

    /* for printing a news file */
    mkvar(&News_File, Spice_Lib_Dir, "news", "SPICE_NEWS");
    /* help directory, not used in Windows mode */
    mkvar(&Help_Path, Spice_Lib_Dir, "helpdir", "SPICE_HELP_DIR");
    /* where spinit is found */
    mkvar(&Lib_Path, Spice_Lib_Dir, "scripts", "SPICE_SCRIPTS");
    /* used to call ngspice with aspice command, not used in Windows mode */
    mkvar(&Spice_Path, Spice_Exec_Dir, "ngspice", "SPICE_PATH");
    tfree(temp);
    /* may be used to store input files (*.lib, *.include, ...) */
    /* get directory where ngspice resides */
#if defined (HAS_WINGUI) || defined (__MINGW32__) || defined (_MSC_VER)
    {
        ngpath = ngdirname(argv0);
        /* set path either to <ngspice-bin-directory>/input or,
        if set, to environment variable NGSPICE_INPUT_DIR */
        mkvar(&Inp_Path, ngpath, "input", "NGSPICE_INPUT_DIR");
        tfree(ngpath);
    }
#else
    NG_IGNORE(argv0);
    /* set path either to environment variable NGSPICE_INPUT_DIR
    (if given) or to NULL */
    env_overr(&Inp_Path, "NGSPICE_INPUT_DIR");
    Inp_Path = copy(Inp_Path); /* allow tfree */
#endif
    env_overr(&Spice_Host, "SPICE_HOST"); /* aspice */
    env_overr(&Bug_Addr, "SPICE_BUGADDR");
    env_overr(&Def_Editor, "SPICE_EDITOR");
    
    /* Set raw file mode, 0 by default (binary) set in conf.c, 
    may be overridden by environmental
    variable, not sure if acknowledged everywhere in ngspice */
    env_overr(&temp, "SPICE_ASCIIRAWFILE");
    if(temp)
       AsciiRawFile = atoi(temp);

    /* path of the ngspice executable */
    if (argv0) {
        Spice_Exec_Path = copy(argv0);
        /* find the last occurence of "ngspice" in Spice_Exec_Path */
        char* path_end = strstr(Spice_Exec_Path, "ngspice");
        if (path_end) {
            char* exec_only = strstr(path_end + 7, "ngspice");
            while (exec_only) {
                path_end = strstr(exec_only, "ngspice");
                if (path_end)
                    exec_only = strstr(path_end + 7, "ngspice");
            }
            if (path_end)
                *path_end = '\0';
        }
    }
    else
        Spice_Exec_Path = NULL;
}

void
destroy_ivars(void)
{
    tfree(News_File);
    tfree(Help_Path);
    tfree(Lib_Path);
    tfree(Spice_Path);
    tfree(Inp_Path);
    tfree(Spice_Exec_Path);
}