#include <stdlib.h>

#include <string.h>

#include <isl_int.h>

extern int isl_sioimath_decode(isl_sioimath val, int32_t *small, mp_int *big);

extern int isl_sioimath_decode_big(isl_sioimath val, mp_int *big);

extern int isl_sioimath_decode_small(isl_sioimath val, int32_t *small);

extern isl_sioimath isl_sioimath_encode_small(int32_t val);

extern isl_sioimath isl_sioimath_encode_big(mp_int val);

extern int isl_sioimath_is_small(isl_sioimath val);

extern int isl_sioimath_is_big(isl_sioimath val);

extern int32_t isl_sioimath_get_small(isl_sioimath val);

extern mp_int isl_sioimath_get_big(isl_sioimath val);

extern void isl_siomath_uint32_to_digits(uint32_t num, mp_digit *digits,

	mp_size *used);

extern void isl_siomath_ulong_to_digits(unsigned long num, mp_digit *digits,

	mp_size *used);

extern void isl_siomath_uint64_to_digits(uint64_t num, mp_digit *digits,

	mp_size *used);

extern mp_int isl_sioimath_bigarg_src(isl_sioimath arg,

	isl_sioimath_scratchspace_t *scratch);

extern mp_int isl_sioimath_siarg_src(signed long arg,

	isl_sioimath_scratchspace_t *scratch);

extern mp_int isl_sioimath_si64arg_src(int64_t arg,

	isl_sioimath_scratchspace_t *scratch);

extern mp_int isl_sioimath_uiarg_src(unsigned long arg,

	isl_sioimath_scratchspace_t *scratch);

extern mp_int isl_sioimath_reinit_big(isl_sioimath_ptr ptr);

extern void isl_sioimath_set_small(isl_sioimath_ptr ptr, int32_t val);

extern void isl_sioimath_set_int32(isl_sioimath_ptr ptr, int32_t val);

extern void isl_sioimath_set_int64(isl_sioimath_ptr ptr, int64_t val);

extern void isl_sioimath_promote(isl_sioimath_ptr dst);

extern void isl_sioimath_try_demote(isl_sioimath_ptr dst);

extern void isl_sioimath_init(isl_sioimath_ptr dst);

extern void isl_sioimath_clear(isl_sioimath_ptr dst);

extern void isl_sioimath_set(isl_sioimath_ptr dst, isl_sioimath_src val);

extern void isl_sioimath_set_si(isl_sioimath_ptr dst, long val);

extern void isl_sioimath_set_ui(isl_sioimath_ptr dst, unsigned long val);

extern int isl_sioimath_fits_slong(isl_sioimath_src val);

extern long isl_sioimath_get_si(isl_sioimath_src val);

extern int isl_sioimath_fits_ulong(isl_sioimath_src val);

extern unsigned long isl_sioimath_get_ui(isl_sioimath_src val);

extern double isl_sioimath_get_d(isl_sioimath_src val);

extern char *isl_sioimath_get_str(isl_sioimath_src val);

extern void isl_sioimath_abs(isl_sioimath_ptr dst, isl_sioimath_src arg);

extern void isl_sioimath_neg(isl_sioimath_ptr dst, isl_sioimath_src arg);

extern void isl_sioimath_swap(isl_sioimath_ptr lhs, isl_sioimath_ptr rhs);

extern void isl_sioimath_add_ui(isl_sioimath_ptr dst, isl_sioimath lhs,

	unsigned long rhs);

extern void isl_sioimath_sub_ui(isl_sioimath_ptr dst, isl_sioimath lhs,

	unsigned long rhs);

extern void isl_sioimath_add(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_sub(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_mul(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_mul_2exp(isl_sioimath_ptr dst, isl_sioimath lhs,

	unsigned long rhs);

extern void isl_sioimath_mul_si(isl_sioimath_ptr dst, isl_sioimath lhs,

	signed long rhs);

extern void isl_sioimath_mul_ui(isl_sioimath_ptr dst, isl_sioimath lhs,

	unsigned long rhs);

extern void isl_sioimath_pow_ui(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	unsigned long rhs);

extern void isl_sioimath_addmul(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_addmul_ui(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	unsigned long rhs);

extern void isl_sioimath_submul(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_submul_ui(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	unsigned long rhs);

/* Implements the Euclidean algorithm to compute the greatest common divisor of

 * two values in small representation.

 */

static uint32_t isl_sioimath_smallgcd(int32_t lhs, int32_t rhs)

{

	uint32_t dividend, divisor, remainder;

	dividend = labs(lhs);

	divisor = labs(rhs);

	while (divisor) {

		remainder = dividend % divisor;

		dividend = divisor;

		divisor = remainder;

	}

	return dividend;

}

/* Compute the greatest common divisor.

 *

 * Per GMP convention, gcd(0,0)==0 and otherwise always positive.

 */

void isl_sioimath_gcd(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs)

{

	int32_t lhssmall, rhssmall;

	uint32_t smallgcd;

	isl_sioimath_scratchspace_t scratchlhs, scratchrhs;

	if (isl_sioimath_decode_small(lhs, &lhssmall) &&

	    isl_sioimath_decode_small(rhs, &rhssmall)) {

		smallgcd = isl_sioimath_smallgcd(lhssmall, rhssmall);

		isl_sioimath_set_small(dst, smallgcd);

		return;

	}

	impz_gcd(isl_sioimath_reinit_big(dst),

	    isl_sioimath_bigarg_src(lhs, &scratchlhs),

	    isl_sioimath_bigarg_src(rhs, &scratchrhs));

	isl_sioimath_try_demote(dst);

}

/* Compute the lowest common multiple of two numbers.

 */

void isl_sioimath_lcm(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs)

{

	int32_t lhssmall, rhssmall;

	uint32_t smallgcd;

	uint64_t multiple;

	isl_sioimath_scratchspace_t scratchlhs, scratchrhs;

	if (isl_sioimath_decode_small(lhs, &lhssmall) &&

	    isl_sioimath_decode_small(rhs, &rhssmall)) {

		if (lhssmall == 0 || rhssmall == 0) {

			isl_sioimath_set_small(dst, 0);

			return;

		}

		smallgcd = isl_sioimath_smallgcd(lhssmall, rhssmall);

		multiple = (uint64_t) abs(lhssmall) * (uint64_t) abs(rhssmall);

		isl_sioimath_set_int64(dst, multiple / smallgcd);

		return;

	}

	impz_lcm(isl_sioimath_reinit_big(dst),

	    isl_sioimath_bigarg_src(lhs, &scratchlhs),

	    isl_sioimath_bigarg_src(rhs, &scratchrhs));

	isl_sioimath_try_demote(dst);

}

extern void isl_sioimath_tdiv_q(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_tdiv_q_ui(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	unsigned long rhs);

extern void isl_sioimath_cdiv_q(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_fdiv_q(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern void isl_sioimath_fdiv_q_ui(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	unsigned long rhs);

extern void isl_sioimath_fdiv_r(isl_sioimath_ptr dst, isl_sioimath_src lhs,

	isl_sioimath_src rhs);

/* Parse a number from a string.

 * If it has less than 10 characters then it will fit into the small

 * representation (i.e. strlen("2147483647")). Otherwise, let IMath parse it.

 */

void isl_sioimath_read(isl_sioimath_ptr dst, const char *str)

{

	int32_t small;

	if (strlen(str) < 10) {

		small = strtol(str, NULL, 10);

		isl_sioimath_set_small(dst, small);

		return;

	}

	mp_int_read_string(isl_sioimath_reinit_big(dst), 10, str);

	isl_sioimath_try_demote(dst);

}

extern int isl_sioimath_sgn(isl_sioimath_src arg);

extern int isl_sioimath_cmp(isl_sioimath_src lhs, isl_sioimath_src rhs);

extern int isl_sioimath_cmp_si(isl_sioimath_src lhs, signed long rhs);

extern int isl_sioimath_abs_cmp(isl_sioimath_src lhs, isl_sioimath_src rhs);

extern int isl_sioimath_is_divisible_by(isl_sioimath_src lhs,

	isl_sioimath_src rhs);

extern uint32_t isl_sioimath_hash(isl_sioimath_src arg, uint32_t hash);

extern size_t isl_sioimath_sizeinbase(isl_sioimath_src arg, int base);

extern void isl_sioimath_print(FILE *out, isl_sioimath_src i, int width);

/* Print an isl_int to FILE*. Adds space padding to the left until at least

 * width characters are printed.

 */

void isl_sioimath_print(FILE *out, isl_sioimath_src i, int width)

{

	size_t len;

	int32_t small;

	mp_int big;

	char *buf;

	if (isl_sioimath_decode_small(i, &small)) {

		fprintf(out, "%*" PRIi32, width, small);

		return;

	}

	big = isl_sioimath_get_big(i);

	len = mp_int_string_len(big, 10);

	buf = malloc(len);

	mp_int_to_string(big, 10, buf, len);

	fprintf(out, "%*s", width, buf);

	free(buf);

}

/* Print a number to stdout. Meant for debugging.

 */

void isl_sioimath_dump(isl_sioimath_src arg)

{

	isl_sioimath_print(stdout, arg, 0);

}