#ifndef UC_BITEVEC_H_
#define UC_BITEVEC_H_

#include <limits.h>

#ifdef __cplusplus
extern "C" {
#endif

/** Backing type of the bit vector*/
typedef unsigned long uc_bv_integer;

struct UCBitVec {
    //storage for the bits
    uc_bv_integer *vec;
    //number of elements int the above vec.
    size_t vec_len;
};

/**
 *  Evaluates the number of uc_bv_integer elements  required for a bitvec to store nbit bits.
 */
#define UC_BV_LEN(nbits)   ((nbits/(sizeof(uc_bv_integer)*CHAR_BIT)) + (nbits % (sizeof(uc_bv_integer)*CHAR_BIT) == 0 ? 0 : 1))

/** Initialize a bitvec with predefined backing array.
 * The backing array element type must be uc_bv_integer
 * Use as
 * @code
 * uc_bv_integer v[10];
 * struct UCBitVec v = UC_BV_STATIC_INIT(v);
 * @endcode
 */
#define UC_BV_STATIC_INIT(vec_data)\
{\
vec_data,\
sizeof vec_data/sizeof vec_data[0]}


/**
 * Returns a newly malloced bitvec, capable of storing at least nbits bits
 * All bits are initially zero.
 *
 */
struct UCBitVec *uc_bv_new(size_t nbits);

/** free a bitvec previously allocated by bitvec_new
 */
void uc_bv_free(struct UCBitVec *v);

//Note that accessing a bit beyond the nbits originally initialized
//for the given bitvec is undedefined

/** Sets bit number b */
void uc_bv_set_bit(struct UCBitVec *v,int b);

/** Clears bit number b*/
void uc_bv_clr_bit(struct UCBitVec *v,int b);

/** Gets the current value (0 or 1) of bit number @b*/
int uc_bv_get_bit(const struct UCBitVec *v,int b);

/** Sets all bits to zero */
void uc_bv_clr_all(struct UCBitVec *v);

/** Sets all bits to one */
void uc_bv_set_all(struct UCBitVec *v);

/** Initialize bits from a array of ints, each array element maps to one bit.
 * The bits are initialized from the int array so zero maps to zero and non-zero maps to one.
 * e..g to set the 5 first bits, to 01110:
 * int a[] = {0,1,1,1,0};
 * set_bits_from_array(v,a,5);
 * */
void uc_bv_set_bits_from_array(struct UCBitVec *v,const char *array,size_t array_len);

/** Find the index of the first zero bit in the bitvec.
 * @param v The bitvec to search
 * @return The index of the first zero bit, or -1 if all bits are set
 */
int uc_bv_find_first_zero(const struct UCBitVec *v);

#ifdef __cplusplus
}
#endif

#endif