/* C wrappers around some zfs calls and C in general that should simplify
 * using libzfs from go language, and make go code shorter and more readable.
 */

#include <libzfs.h>
#include <memory.h>
#include <string.h>
#include <stdio.h>

#include "zpool.h"

char *sZPOOL_CONFIG_VERSION = ZPOOL_CONFIG_VERSION;
char *sZPOOL_CONFIG_POOL_NAME = ZPOOL_CONFIG_POOL_NAME;
char *sZPOOL_CONFIG_POOL_STATE = ZPOOL_CONFIG_POOL_STATE;
char *sZPOOL_CONFIG_POOL_TXG = ZPOOL_CONFIG_POOL_TXG;
char *sZPOOL_CONFIG_POOL_GUID = ZPOOL_CONFIG_POOL_GUID;
char *sZPOOL_CONFIG_CREATE_TXG = ZPOOL_CONFIG_CREATE_TXG;
char *sZPOOL_CONFIG_TOP_GUID = ZPOOL_CONFIG_TOP_GUID;
char *sZPOOL_CONFIG_VDEV_TREE = ZPOOL_CONFIG_VDEV_TREE;
char *sZPOOL_CONFIG_TYPE = ZPOOL_CONFIG_TYPE;
char *sZPOOL_CONFIG_CHILDREN = ZPOOL_CONFIG_CHILDREN;
char *sZPOOL_CONFIG_ID = ZPOOL_CONFIG_ID;
char *sZPOOL_CONFIG_GUID = ZPOOL_CONFIG_GUID;
char *sZPOOL_CONFIG_PATH = ZPOOL_CONFIG_PATH;
char *sZPOOL_CONFIG_DEVID = ZPOOL_CONFIG_DEVID;
char *sZPOOL_CONFIG_METASLAB_ARRAY = ZPOOL_CONFIG_METASLAB_ARRAY;
char *sZPOOL_CONFIG_METASLAB_SHIFT = ZPOOL_CONFIG_METASLAB_SHIFT;
char *sZPOOL_CONFIG_ASHIFT = ZPOOL_CONFIG_ASHIFT;
char *sZPOOL_CONFIG_ASIZE = ZPOOL_CONFIG_ASIZE;
char *sZPOOL_CONFIG_DTL = ZPOOL_CONFIG_DTL;
char *sZPOOL_CONFIG_SCAN_STATS = ZPOOL_CONFIG_SCAN_STATS;
char *sZPOOL_CONFIG_VDEV_STATS = ZPOOL_CONFIG_VDEV_STATS;
char *sZPOOL_CONFIG_WHOLE_DISK = ZPOOL_CONFIG_WHOLE_DISK;
char *sZPOOL_CONFIG_ERRCOUNT = ZPOOL_CONFIG_ERRCOUNT;
char *sZPOOL_CONFIG_NOT_PRESENT = ZPOOL_CONFIG_NOT_PRESENT;
char *sZPOOL_CONFIG_SPARES = ZPOOL_CONFIG_SPARES;
char *sZPOOL_CONFIG_IS_SPARE = ZPOOL_CONFIG_IS_SPARE;
char *sZPOOL_CONFIG_NPARITY = ZPOOL_CONFIG_NPARITY;
char *sZPOOL_CONFIG_HOSTID = ZPOOL_CONFIG_HOSTID;
char *sZPOOL_CONFIG_HOSTNAME = ZPOOL_CONFIG_HOSTNAME;
char *sZPOOL_CONFIG_LOADED_TIME = ZPOOL_CONFIG_LOADED_TIME;
char *sZPOOL_CONFIG_UNSPARE = ZPOOL_CONFIG_UNSPARE;
char *sZPOOL_CONFIG_PHYS_PATH = ZPOOL_CONFIG_PHYS_PATH;
char *sZPOOL_CONFIG_IS_LOG = ZPOOL_CONFIG_IS_LOG;
char *sZPOOL_CONFIG_L2CACHE = ZPOOL_CONFIG_L2CACHE;
char *sZPOOL_CONFIG_HOLE_ARRAY = ZPOOL_CONFIG_HOLE_ARRAY;
char *sZPOOL_CONFIG_VDEV_CHILDREN = ZPOOL_CONFIG_VDEV_CHILDREN;
char *sZPOOL_CONFIG_IS_HOLE = ZPOOL_CONFIG_IS_HOLE;
char *sZPOOL_CONFIG_DDT_HISTOGRAM = ZPOOL_CONFIG_DDT_HISTOGRAM;
char *sZPOOL_CONFIG_DDT_OBJ_STATS = ZPOOL_CONFIG_DDT_OBJ_STATS;
char *sZPOOL_CONFIG_DDT_STATS = ZPOOL_CONFIG_DDT_STATS;
char *sZPOOL_CONFIG_SPLIT = ZPOOL_CONFIG_SPLIT;
char *sZPOOL_CONFIG_ORIG_GUID = ZPOOL_CONFIG_ORIG_GUID;
char *sZPOOL_CONFIG_SPLIT_GUID = ZPOOL_CONFIG_SPLIT_GUID;
char *sZPOOL_CONFIG_SPLIT_LIST = ZPOOL_CONFIG_SPLIT_LIST;
char *sZPOOL_CONFIG_REMOVING = ZPOOL_CONFIG_REMOVING;
char *sZPOOL_CONFIG_RESILVER_TXG = ZPOOL_CONFIG_RESILVER_TXG;
char *sZPOOL_CONFIG_COMMENT = ZPOOL_CONFIG_COMMENT;
char *sZPOOL_CONFIG_SUSPENDED = ZPOOL_CONFIG_SUSPENDED;
char *sZPOOL_CONFIG_TIMESTAMP = ZPOOL_CONFIG_TIMESTAMP;
char *sZPOOL_CONFIG_BOOTFS = ZPOOL_CONFIG_BOOTFS;
char *sZPOOL_CONFIG_MISSING_DEVICES = ZPOOL_CONFIG_MISSING_DEVICES;
char *sZPOOL_CONFIG_LOAD_INFO = ZPOOL_CONFIG_LOAD_INFO;
char *sZPOOL_CONFIG_REWIND_INFO = ZPOOL_CONFIG_REWIND_INFO;
char *sZPOOL_CONFIG_UNSUP_FEAT = ZPOOL_CONFIG_UNSUP_FEAT;
char *sZPOOL_CONFIG_ENABLED_FEAT = ZPOOL_CONFIG_ENABLED_FEAT;
char *sZPOOL_CONFIG_CAN_RDONLY = ZPOOL_CONFIG_CAN_RDONLY;
char *sZPOOL_CONFIG_FEATURES_FOR_READ = ZPOOL_CONFIG_FEATURES_FOR_READ;
char *sZPOOL_CONFIG_FEATURE_STATS = ZPOOL_CONFIG_FEATURE_STATS;
char *sZPOOL_CONFIG_ERRATA = ZPOOL_CONFIG_ERRATA;
char *sZPOOL_CONFIG_OFFLINE = ZPOOL_CONFIG_OFFLINE;
char *sZPOOL_CONFIG_FAULTED = ZPOOL_CONFIG_FAULTED;
char *sZPOOL_CONFIG_DEGRADED = ZPOOL_CONFIG_DEGRADED;
char *sZPOOL_CONFIG_REMOVED = ZPOOL_CONFIG_REMOVED;
char *sZPOOL_CONFIG_FRU = ZPOOL_CONFIG_FRU;
char *sZPOOL_CONFIG_AUX_STATE = ZPOOL_CONFIG_AUX_STATE;
char *sZPOOL_REWIND_POLICY = ZPOOL_REWIND_POLICY;
char *sZPOOL_REWIND_REQUEST = ZPOOL_REWIND_REQUEST;
char *sZPOOL_REWIND_REQUEST_TXG = ZPOOL_REWIND_REQUEST_TXG;
char *sZPOOL_REWIND_META_THRESH = ZPOOL_REWIND_META_THRESH;
char *sZPOOL_REWIND_DATA_THRESH = ZPOOL_REWIND_DATA_THRESH;
char *sZPOOL_CONFIG_LOAD_TIME = ZPOOL_CONFIG_LOAD_TIME;
char *sZPOOL_CONFIG_LOAD_DATA_ERRORS = ZPOOL_CONFIG_LOAD_DATA_ERRORS;
char *sZPOOL_CONFIG_REWIND_TIME = ZPOOL_CONFIG_REWIND_TIME;

static char _lasterr_[1024];

const char *lasterr(void) {
	return _lasterr_;
}

zpool_list_t *create_zpool_list_item() {
	zpool_list_t *zlist = malloc(sizeof(zpool_list_t));
	memset(zlist, 0, sizeof(zpool_list_t));
	return zlist;
}

int zpool_list_callb(zpool_handle_t *pool, void *data) {
	zpool_list_t **lroot = (zpool_list_t**)data;
	zpool_list_t *nroot = create_zpool_list_item();

	if ( !((*lroot)->zph) ) {
		(*lroot)->zph = pool;
	} else {
		nroot->zph = pool;
		nroot->pnext = (void*)*lroot;
		*lroot = nroot;
	}
	return 0;
}

int zpool_list(libzfs_handle_t *libzfs, zpool_list_t **first) {
	int err = 0;
	zpool_list_t *zlist = create_zpool_list_item();
	err = zpool_iter(libzfs, zpool_list_callb, &zlist);
	if ( zlist->zph ) {
		*first = zlist;
	} else {
		*first = 0;
		free(zlist);
	}
	return err;
}

zpool_list_t* zpool_list_open(libzfs_handle_t *libzfs, const char *name) {
	zpool_list_t *zlist = create_zpool_list_item();
	zlist->zph = zpool_open(libzfs, name);
	if ( zlist->zph ) {
		return zlist;
	} else {
		free(zlist);
	}
	return 0;
}

zpool_list_t *zpool_next(zpool_list_t *pool) {
	return pool->pnext;
}

void zpool_list_close(zpool_list_t *pool) {
	zpool_close(pool->zph);
	free(pool);
}

property_list_t *new_property_list() {
	property_list_t *r = malloc(sizeof(property_list_t));
	memset(r, 0, sizeof(property_list_t));
	return r;
}

void free_properties(property_list_t *root) {
	if (root != 0) {
		property_list_t *tmp = 0;
		do {
			tmp = root->pnext;
			free(root);
			root = tmp;
		} while(tmp);
	}
}

property_list_t *next_property(property_list_t *list) {
	if (list != 0) {
		return list->pnext;
	}
	return list;
}


void zprop_source_tostr(char *dst, zprop_source_t source) {
	switch (source) {
	case ZPROP_SRC_NONE:
		strcpy(dst, "none");
		break;
	case ZPROP_SRC_TEMPORARY:
		strcpy(dst, "temporary");
		break;
	case ZPROP_SRC_LOCAL:
		strcpy(dst, "local");
		break;
	case ZPROP_SRC_INHERITED:
		strcpy(dst, "inherited");
		break;
	case ZPROP_SRC_RECEIVED:
		strcpy(dst, "received");
		break;
	default:
		strcpy(dst, "default");
		break;
	}
}


int read_zpool_property(zpool_handle_t *zh, property_list_t *list, int prop) {

	int r = 0;
	zprop_source_t source;

	r = zpool_get_prop(zh, prop,
		list->value, INT_MAX_VALUE, &source);
	if (r == 0) {
		// strcpy(list->name, zpool_prop_to_name(prop));
		zprop_source_tostr(list->source, source);
	}
	list->property = (int)prop;
	return r;
}

int read_append_zpool_property(zpool_handle_t *zh, property_list_t **proot,
	zpool_prop_t prop) {
	int r = 0;
	property_list_t *newitem = NULL, *root = *proot;
	newitem = new_property_list();

	r = read_zpool_property(zh, newitem, prop);
	// printf("p: %s %s %s\n", newitem->name, newitem->value, newitem->source);
	newitem->pnext = root;
	*proot = root = newitem;
	if (r != 0) {
		free_properties(root);
		*proot = NULL;
	}
	return r;
}

property_list_t *read_zpool_properties(zpool_handle_t *zh) {
	// read pool name as first property
	property_list_t *root = NULL, *list = NULL;

	int r = read_append_zpool_property(zh, &root, ZPOOL_PROP_NAME);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_SIZE);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_CAPACITY);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_ALTROOT);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_HEALTH);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_GUID);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_VERSION);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_BOOTFS);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_DELEGATION);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_AUTOREPLACE);
	if (r != 0) {
		return 0;
	}


	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_CACHEFILE);
	if (r != 0) {
		return 0;
	}


	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_FAILUREMODE);
	if (r != 0) {
		return 0;
	}


	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_LISTSNAPS);
	if (r != 0) {
		return 0;
	}


	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_AUTOEXPAND);
	if (r != 0) {
		return 0;
	}


	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_DEDUPDITTO);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_DEDUPRATIO);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_FREE);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_ALLOCATED);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_READONLY);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_ASHIFT);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_COMMENT);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_EXPANDSZ);
	if (r != 0) {
		return 0;
	}

	r = read_append_zpool_property(zh, &root, ZPOOL_PROP_FREEING);
	if (r != 0) {
		return 0;
	}


	list = new_property_list();
	list->property = ZPOOL_NUM_PROPS;
	sprintf(list->value, "%d", ZPOOL_NUM_PROPS);
	list->pnext = root;
	zprop_source_tostr(list->source, ZPROP_SRC_NONE);
	root = list;

	// printf("Finished properties reading.\n");
	return root;
}

pool_state_t zpool_read_state(zpool_handle_t *zh) {
	return zpool_get_state(zh);
}


const char *gettext(const char *txt) {
	return txt;
}
/*
 * Add a property pair (name, string-value) into a property nvlist.
 */
int
add_prop_list(const char *propname, char *propval, nvlist_t **props,
	boolean_t poolprop) {
	zpool_prop_t prop = ZPROP_INVAL;
	zfs_prop_t fprop;
	nvlist_t *proplist;
	const char *normnm;
	char *strval;

	if (*props == NULL &&
	    nvlist_alloc(props, NV_UNIQUE_NAME, 0) != 0) {
		(void) snprintf(_lasterr_, 1024, "internal error: out of memory");
		return (1);
	}

	proplist = *props;

	if (poolprop) {
		const char *vname = zpool_prop_to_name(ZPOOL_PROP_VERSION);

		if ((prop = zpool_name_to_prop(propname)) == ZPROP_INVAL &&
		    !zpool_prop_feature(propname)) {
			(void) snprintf(_lasterr_, 1024, "property '%s' is "
			    "not a valid pool property", propname);
			return (2);
		}

		/*
		 * feature@ properties and version should not be specified
		 * at the same time.
		 */
		// if ((prop == ZPROP_INVAL && zpool_prop_feature(propname) &&
		//     nvlist_exists(proplist, vname)) ||
		//     (prop == ZPOOL_PROP_VERSION &&
		//     prop_list_contains_feature(proplist))) {
		// 	(void) fprintf(stderr, gettext("'feature@' and "
		// 	    "'version' properties cannot be specified "
		// 	    "together\n"));
		// 	return (2);
		// }


		if (zpool_prop_feature(propname))
			normnm = propname;
		else
			normnm = zpool_prop_to_name(prop);
	} else {
		if ((fprop = zfs_name_to_prop(propname)) != ZPROP_INVAL) {
			normnm = zfs_prop_to_name(fprop);
		} else {
			normnm = propname;
		}
	}

	if (nvlist_lookup_string(proplist, normnm, &strval) == 0 &&
	    prop != ZPOOL_PROP_CACHEFILE) {
		(void) snprintf(_lasterr_, 1024, "property '%s' "
		    "specified multiple times", propname);
		return (2);
	}

	if (nvlist_add_string(proplist, normnm, propval) != 0) {
		(void) snprintf(_lasterr_, 1024, "internal "
		    "error: out of memory\n");
		return (1);
	}

	return (0);
}

int nvlist_lookup_uint64_array_vds(nvlist_t *nv, const char *p,
	vdev_stat_t **vds, uint_t *c) {
		return nvlist_lookup_uint64_array(nv, p, (uint64_t**)vds, c);
}

int nvlist_lookup_uint64_array_ps(nvlist_t *nv, const char *p,
	pool_scan_stat_t **vds, uint_t *c) {
		return nvlist_lookup_uint64_array(nv, p, (uint64_t**)vds, c);
}

nvlist_t** nvlist_alloc_array(int count) {
	return malloc(count*sizeof(nvlist_t*));
}

void nvlist_array_set(nvlist_t** a, int i, nvlist_t *item) {
	a[i] = item;
}

void nvlist_free_array(nvlist_t **a) {
	free(a);
}

nvlist_t *nvlist_array_at(nvlist_t **a, uint_t i) {
	return a[i];
}

int refresh_stats(zpool_list_t *pool)
{
	boolean_t missing;
	int err = zpool_refresh_stats(pool->zph, &missing);
	if ( err != 0 ) {
		return err;
	}
	if ( missing == B_TRUE ) {
		return -1;
	}
	return 0;
}