preferences.c

#include "crb/preferences.h"

static struct crb_preferences *prefs;

int crb_preferences_initialize(char *prefs_file)
{
    if (prefs != NULL)
        crb_preferences_cleanup();

    if (prefs_file == NULL) {
        printf("Must specify a valid preferences file.\n");
        return 0;
    }

    prefs = malloc(sizeof(struct crb_preferences));

    prefs->file = strdup(prefs_file);

    INIT_LIST_HEAD(&prefs->list);

    prefs->lua_state = lua_open();
    luaL_openlibs(prefs->lua_state);

    crb_preferences_load_prefs();

    return 1;
}

int crb_preferences_cleanup(void)
{
    free(prefs->file);
    prefs->file = NULL;

    lua_close(prefs->lua_state);
    prefs->lua_state = NULL;

    free(prefs);
    prefs = NULL;

    return 1;
}

static int crb_preferences_clear_prefs(void)
{
    struct crb_preference *tmp;
    struct list_head *pos, *q;

    list_for_each_safe(pos, q, &prefs->list) {
        tmp = list_entry(pos, struct crb_preference, preferences);
        list_del(pos);
        if (tmp->type == PREFERENCE_STRING)
            free(tmp->svalue);
        free(tmp);
    }

    return 1;
}

int crb_preferences_load_prefs(void)
{
    struct crb_preference *pref;

    if (prefs == NULL || prefs->lua_state == NULL) {
        printf("Attempted to load preferences before performing initialization.\n");
        return 0;
    }

    crb_preferences_clear_prefs();

    /* Set defaults first */

    pref = malloc(sizeof(struct crb_preference));
    pref->name = PREFERENCE_SCREENHEIGHT;
    pref->type = PREFERENCE_INTEGER;
    pref->ivalue = PREFERENCE_SCREENHEIGHT_DEFAULT;
    list_add(&(pref->preferences), &(prefs->list));

    pref = malloc(sizeof(struct crb_preference));
    pref->name = PREFERENCE_SCREENWIDTH;
    pref->type = PREFERENCE_INTEGER;
    pref->ivalue = PREFERENCE_SCREENWIDTH_DEFAULT;
    list_add(&(pref->preferences), &(prefs->list));

    /* Load preferences from Lua file */
    if (luaL_loadfile(prefs->lua_state, prefs->file) || lua_pcall(prefs->lua_state, 0, 0, 0)) {
        printf("Error loading preferences file:\n%s\n", lua_tostring(prefs->lua_state, -1));
        return 0;
    }

    lua_getglobal(prefs->lua_state, PREFERENCE_SCREENHEIGHT);

    /* todo */

    return 1;
}

static struct crb_preference *crb_preferences_get_pref(const char *name)
{
    struct list_head *pos;
    struct crb_preference *pref;

    if (prefs == NULL || name == NULL)
        return NULL;

    list_for_each(pos, &prefs->list) {
        pref = list_entry(pos, struct crb_preference, preferences);
        if (!strcmp(pref->name, name))
            return pref;
    }

    return NULL;
}

int crb_preferences_pref_exists(const char *name)
{
    return crb_preferences_get_pref(name) != NULL;
}

int crb_preferences_get_int(const char *name, int *value)
{
    struct crb_preference *pref = crb_preferences_get_pref(name);

    if (pref == NULL || pref->type != PREFERENCE_INTEGER)
        return 0;

    *value = pref->ivalue;

    return 1;
}

int crb_preferences_get_string(const char *name, char **value)
{
    struct crb_preference *pref = crb_preferences_get_pref(name);

    if (pref == NULL || pref->type != PREFERENCE_STRING)
        return 0;

    *value = strdup(pref->svalue);

    return 1;
}

int crb_preferences_put_int(const char *name, int value)
{
    struct crb_preference *pref = crb_preferences_get_pref(name);

    if (prefs == NULL)
        return 0;

    if (pref == NULL) {
        pref = malloc(sizeof(struct crb_preference));
        pref->name = name;

        list_add(&(pref->preferences), &(prefs->list));
    }

    pref->type = PREFERENCE_INTEGER;

    if (pref->svalue != NULL)
        free(pref->svalue);
    pref->svalue = NULL;

    pref->ivalue = value;

    return 1;
}

int crb_preferences_put_string(const char *name, char *value)
{
    struct crb_preference *pref = crb_preferences_get_pref(name);

    if (prefs == NULL)
        return 0;

    if (pref == NULL) {
        pref = malloc(sizeof(struct crb_preference));
        pref->name = name;

        list_add(&(pref->preferences), &(prefs->list));
    }

    pref->type = PREFERENCE_STRING;

    if (pref->svalue != NULL)
        free(pref->svalue);
    pref->ivalue = 0;

    pref->svalue = strdup(value);

    return 1;
}

int crb_preferences_save_prefs(void)
{
    /* todo */
}

preferences.h

#ifndef PREFERENCES_H
#define PREFERENCES_H

#include "universal_include.h"

/* Preference constants */
#define PREFERENCE_SCREENWIDTH  "ScreenWidth"
#define PREFERENCE_SCREENHEIGHT "ScreenHeight"

/* Preference defaults */
#define PREFERENCE_SCREENWIDTH_DEFAULT  854
#define PREFERENCE_SCREENHEIGHT_DEFAULT 480

enum preference_type {
    PREFERENCE_INTEGER,
    PREFERENCE_STRING
};

struct crb_preference {
    char             *name;

    int               ivalue;
    char             *svalue;

    int               type;

    struct list_head  preferences;
};

struct crb_preferences {
    char             *file;

    struct list_head  list;

    lua_State        *lua_state;
};

int crb_preferences_initialize(char *prefs_file);
int crb_preferences_cleanup(void);

int crb_preferences_load_prefs(void);
int crb_preferences_save_prefs(void);

int crb_preferences_pref_exists(const char *name);
int crb_preferences_get_int(const char *name, int *value);
int crb_preferences_get_string(const char *name, char **value);

int crb_preferences_put_int(const char *name, int value);
int crb_preferences_put_string(const char *name, char *value);


#endif /* PREFERENCES_H */