#include "server_config.h"
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <glib.h>
#include "gam_error.h"
#include "gam_excludes.h"

typedef struct _gam_exclude gam_exclude;
typedef gam_exclude* gam_exclude_ptr;

struct _gam_exclude {
    const char *pattern;
    GPatternSpec *comp;
    int exclude;	/* 0 == notify, 1 == poll */
};

static int initialized = 0;
static GList *excludes = NULL;
static char *static_excludes[] = {
#ifdef HAVE_LINUX
    "/media/*",
    "/mnt/*",
    "/dev/*",
    "/proc/*",
#endif
    NULL
};

/**
 * gam_exclude_add:
 * @pattern: the pattern to exclude
 * @exclude: 1 to exclude, 0 to include
 *
 * Add an exclude pattern
 *
 * Returns -1 in case of error, and 0 otherwise
 */
int
gam_exclude_add(const char *pattern, int exclude) {
    GPatternSpec *comp;
    gam_exclude_ptr ptr;

    comp = g_pattern_spec_new((const gchar *) pattern);
    if (comp == NULL)
        return(-1);
    ptr = (gam_exclude_ptr) malloc(sizeof(gam_exclude));
    if (ptr == NULL) {
        g_pattern_spec_free(comp);
	return(-1);
    }
    ptr->pattern = g_strdup(pattern);
    ptr->comp = comp;
    ptr->exclude = exclude;
    excludes = g_list_append(excludes, ptr);
    GAM_DEBUG(DEBUG_INFO, "added %s,%d to excludes\n", pattern, exclude);
    return(0);
}

/**
 * gam_exclude_check_all:
 * @filename: the filename to check
 *
 * Check a filename against the exclude patterns
 * The first matching pattern counts, whether positive or negative
 *
 * Returns 1 if a match is found and 0 otherwise.
 */
static int
gam_exclude_check_all(const char *filename) {
    GList *cur;
    gam_exclude_ptr ptr;
    unsigned int len;

    if ((filename == NULL) || (excludes == NULL))
        return(0);
    
    cur = excludes;
    len = strlen(filename);
    while (cur != NULL) {
        ptr = cur->data;
	if ((ptr != NULL) && (ptr->comp != NULL) &&
	    (g_pattern_match(ptr->comp, len, filename, NULL))) {
	    return(ptr->exclude);
	}
	cur = g_list_next(cur);
    }
    return(0);
}

/************************************************************************
 *									*
 *  Files to exclude from kernel watching due to dnotify limitations 	*
 *									*
 ************************************************************************/

/**
 * gam_exclude_init:
 *
 * Initialize the excluding check mechanism
 *
 * Return 0 in case of success and -1 in case of failure.
 */
int
gam_exclude_init(void) {
    unsigned int i;

    if (initialized)
        return(-1);

    for (i = 0;i < (sizeof(static_excludes)/sizeof(static_excludes[0]));i++) {
        if (static_excludes[i] != NULL)
	    gam_exclude_add(static_excludes[i], 1);
    }
    initialized = 1;
    return(0);
}

/**
 * gam_exclude_check:
 * @filename: the absolute file path
 *
 * Check if the file should be monitored using the kernel dnotify
 * mechanism or not.
 *
 * Returns TRUE if the file should not be monitored by dnotify, and FALSE
 *         otherwise.
 */
gboolean
gam_exclude_check(const char *filename) {
    if (gam_exclude_check_all(filename))
        return(TRUE);

    return(FALSE);
}

void            gam_exclude_debug       (void)
{
	GList *l;

	GAM_DEBUG (DEBUG_INFO, "Dumping exclude list\n");
	for (l = excludes;l;l = l->next)
	{
		gam_exclude_ptr exclude = l->data;
		GAM_DEBUG (DEBUG_INFO, "Exclude: use %s on %s\n", exclude->exclude == 0 ? "KERNEL" : "POLL", exclude->pattern);
	}
}