#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

typedef struct {
    char *var;
    char *value;
} cfgEntry;


#define MAX_ENTRIES  20

static int numRead = 0;
static cfgEntry *cfgData [MAX_ENTRIES];

char *GetEnv (const char *env_str)
{
    int i;
    char *ret_val;

    ret_val = getenv (env_str);
    if (ret_val == NULL) {
        assert (cfgData != NULL);
        i = 0;
        while ((i < numRead) && (strcmp (env_str, cfgData [i]->var) != 0)) i++;
        if (i < numRead) ret_val = cfgData [i]->value;
   }

   return (ret_val);
}

void FreeSDDASCfg ()
{
    int i;
    for (i = 0; i < numRead; i++) {
        free (cfgData [i]->var);
        free (cfgData [i]->value);
        free (cfgData [i]);
    }
    numRead = 0;
}

void InitSDDASCfg (char *path)
{
    char tmp [1024];

/* This will open the config file and keep it values in memory. */

    if (numRead == 0) {
        FILE *cfgFile;
        char *value, *ptr;
        int found_config = 0;

        cfgFile = fopen (path, "r");
        if (cfgFile != NULL) {
            while ((numRead < MAX_ENTRIES) && (fgets (tmp, 1024, cfgFile) != NULL)) {
                value = strchr (tmp, '=');
                if (value == NULL) {
                    fprintf (stderr, "Error reading sddas.cfg file - No equal sign!\n");
                } else {
                    cfgData [numRead] = (cfgEntry *) malloc (sizeof (cfgEntry));
                    value [0] = '\0';
                    value++;             /* value is now one past the equal sign */
                    cfgData [numRead]->var = strdup (tmp);
                    if (strcmp (tmp, "SDDAS_CONFIG") == 0) found_config = 1;
                    ptr = strchr (value, '"');
                    if (ptr == NULL) {
                        fprintf (stderr, "Error reading sddas.cfg file - no leading quote!\n");
                    } else {
                        ptr [0] = '\0';
                        ptr++;             /* ptr is now a correct value with a trailing "*/
                        value = strrchr (ptr, '"');
                        if (value == NULL) {
                            fprintf (stderr, "Error reading sddas.cfg file - no trailing quote!\n");
                        } else {
                            value [0] = '\0';
                            cfgData [numRead]->value = strdup (ptr);
                            numRead++;
                        }
                    }
                }
            }
            fclose (cfgFile);
        }

/* If SDDAS_CONFIG is not set, set it! */

        if (found_config == 0) {
            strcpy (tmp, GetEnv ("SDDAS_HOME"));
            strcat (tmp, "/config");
            cfgData [numRead] = (cfgEntry *) malloc (sizeof (cfgEntry));
            cfgData [numRead]->var = strdup ("SDDAS_CONFIG");
            cfgData [numRead]->value = strdup (tmp);
            numRead++;
        }
    }
}

#ifdef TEST

int main ()
{
    InitSDDASCfg ("/devel/sddas/config");
    printf ("%s\n", GetEnv ("SDDAS_HICOLOR"));
    FreeSDDASCfg ();
    exit (0);
}

#endif