/*
 * sum_prod.c
 *
 *  Created on: 14/03/2017
 *      Author: pedro
 */

#ifndef __OPENCL_VERSION__

#include <stddef.h>
#include <stdio.h>

#include "sum_prod.h"

#include "../bitmaps.h"
#include "../config.h"
#include "../variables.h"

#endif

#include "../kernels/cl_aux_functions.h"
#if CL_D_TYPE == CL_BITMAP
#include "../kernels/cl_bitmaps.h"
#elif CL_D_TYPE == CL_INTERVAL
#include  "../kernels/cl_intervals.h"
#endif
#include "../kernels/cl_constraints.h"
#include "../kernels/cl_variables.h"
#include "../kernels/cl_ttl.h"

#ifndef __OPENCL_VERSION__

/*
 * Creates a new constraint of the sum type and return the constraint ID
 * X . Y = k
 * X_ids - vector with the ID of the X variables
 * n_vs - maximum number of variables in X (equal to y) vector
 * Y_ids - vector with the ID of the Y variables
 * k - value of the product
 */
unsigned int c_sum_prod(unsigned int* X_ids, unsigned int* Y_ids, unsigned int n_vs, unsigned int k) {
	unsigned int i;

	// set to include in kernel compilation
	USE_CS[SUM_PROD] = 1;
	USE_NON_CS_REIFI[SUM_PROD] = 1;
	REV = 1;

	unsigned int* c_vs = malloc((n_vs * 2) * sizeof(unsigned int));

	for (i = 0; i < n_vs; i++) {
		c_vs[i] = X_ids[i];
	}
	for (; i < n_vs * 2; i++) {
		c_vs[i] = Y_ids[i - n_vs];
	}

	// creates a new generic constraint
	unsigned int c_id = c_new(c_vs, n_vs * 2, NULL, 0, -1);

	// pointers to this type of constraint functions
	CS[c_id].kind = SUM_PROD;
	CS[c_id].check_sol_f = &sum_prod_check;
	CS[c_id].constant_val = (int)k;

	free(c_vs);

	return c_id;
}

/*
 * Creates a new reified constraint of the sum type and return the constraint ID
 * X . Y = k
 * X_ids - vector with the ID of the X variables
 * n_vs - maximum number of variables in X (equal to y) vector
 * Y_ids - vector with the ID of the Y variables
 * k - value of the product
 * reif_v_id - ID of the reification variable
 */
unsigned int c_sum_prod_reif(unsigned int* X_ids, unsigned int* Y_ids, unsigned int n_vs, unsigned int k, int reif_v_id) {
	unsigned int i;

	if (VS[reif_v_id].max > 1) {
		v_del_gt(&VS[reif_v_id], 1);

		if (VS[reif_v_id].n_vals == 0) {
			fprintf(stderr, "\nError: Constraint SUM_PROD_REIF makes model inconsistent at creation:\n");
			exit(-1);
		}
	}

	// set to include in kernel compilation
	USE_CS[SUM_PROD] = 1;
	USE_CS_REIFI[SUM_PROD] = 1;
	REV = 1;

	unsigned int* c_vs = malloc((n_vs * 2) * sizeof(unsigned int));

	for (i = 0; i < n_vs; i++) {
		c_vs[i] = X_ids[i];
	}
	for (; i < n_vs * 2; i++) {
		c_vs[i] = Y_ids[i - n_vs];
	}

	// creates a new generic constraint
	unsigned int c_id = c_new(c_vs, n_vs * 2, NULL, 0, reif_v_id);

	// pointers to this type of constraint functions
	CS[c_id].kind = SUM_PROD;
	CS[c_id].check_sol_f = &sum_prod_check;
	CS[c_id].constant_val = (int)k;

	free(c_vs);

	return c_id;
}

/*
 * Return true if the sum constraint is respected or false if not
 * X . Y = k
 * c - constraint to check if is respected
 * explored - if the CSP was already explored, which mean that all the variables must already be singletons
 * */
bool sum_prod_check(constr* c, bool explored) {
	var** X = c->c_vs;
	var* x;
	int terms = c->n_c_vs / 2;
	var** Y = c->c_vs + terms;
	var* y;
	int k = c->constant_val;
	int sum = 0;
	int i;


	for (i = 0; i < terms; i++) {
		x = X[i];
		y = Y[i];

#if CHECK_SOL_N_VALS
		if ((x->to_label && x->n_vals == 1) || (y->to_label && y->n_vals == 1)) {
			if (explored) {
				fprintf(stderr, "\nError: Constraint SUM_PROD (%d) not respected:\n", c->c_id);

				for (i = 0; i < c->n_c_vs; i++) {
					fprintf(stderr, "Variable ID=%u -> minimum=%u, maximum=%u, number of values=%u\n\n", c->c_vs[i]->v_id, b_get_min_val(&c->c_vs[i]->domain_b),
							b_get_max_val(&c->c_vs[i]->domain_b), b_cnt_vals(&c->c_vs[i]->domain_b));
				}
			}
			return false;
		}
#endif

		sum += x->min * y->min;
	}
	if (sum != k) {
		if (explored) {
			fprintf(stderr, "\nError: Constraint SUM_PROD (%d) not respected:\n", c->c_id);

			for (i = 0; i < c->n_c_vs; i++) {
				fprintf(stderr, "Variable ID=%u -> minimum=%u, maximum=%u, number of values=%u\n\n", c->c_vs[i]->v_id, b_get_min_val(&c->c_vs[i]->domain_b),
						b_get_max_val(&c->c_vs[i]->domain_b), b_cnt_vals(&c->c_vs[i]->domain_b));
			}
		}
		return false;
	}

	return true;
}

#endif

#if CS_SUM_PROD == 1
/*
 * Propagate the domain of the variable with the ID prop_v_id through all the other variables on the same c_numb ID sum_prod constraint
 * X . Y = k
 * prop_ok will be set to 1 if success or to 0 if any domain became empty
 * vs_per_c_idx - vector with all constrained variables ID per constraint, per constraint ID order
 * vs_prop_ - all CSP variables with current step values
 * prop_v_id - variable ID to propagate
 * current_cs - constraint that should be propagated for the variable with prop_v_id ID
 * vs_id_to_prop_ - circular vector with the ids of the variables to propagate
 */
CUDA_FUNC void sum_prod_prop(CL_INTS_MEM int* vs_per_c_idx, CL_MEMORY VARS_PROP* vs_prop_, CL_CS_MEM cl_constr* current_cs, CL_MEMORY unsigned short* vs_id_to_prop_,
		bool* prop_ok CS_IGNORE_FUNC TTL_CTR) {

	int terms = current_cs->n_c_vs / 2;
	int k = current_cs->constant_val;
	int x_id;
	int y_id;
	int min, max;
	bool changed = 0;
	int i;

	// if the sum of the minimum of the products is greater than k
	min = 0;
	for (i = 0; i < terms; i++) {
		CHECK_TTL(ttl_ctr, 90)
		x_id = vs_per_c_idx[i];
		y_id = vs_per_c_idx[terms + i];

		min += V_MIN(vs_prop_[x_id]) * V_MIN(vs_prop_[y_id]);

		if (min > k) {
			*prop_ok = 0;
			return;
		}
	}

	// if the sum of the maximum of the products is lesser than k
	max = 0;
	for (i = 0; i < terms; i++) {
		CHECK_TTL(ttl_ctr, 91)
		x_id = vs_per_c_idx[i];
		y_id = vs_per_c_idx[terms + i];

		max += V_MAX(vs_prop_[x_id]) * V_MAX(vs_prop_[y_id]);
	}

	if (max < k) {
		*prop_ok = 0;
		return;
	}

	// poor man's propagation
	if (min == k) {
		for (i = 0; i < terms; i++) {
			CHECK_TTL(ttl_ctr, 92)
			x_id = vs_per_c_idx[i];
			y_id = vs_per_c_idx[terms + i];

			if (V_N_VALS(vs_prop_[x_id]) > 1) {
				if (V_MIN(vs_prop_[y_id]) != 0) {

					cl_v_del_gt_m(&changed, &vs_prop_[x_id], V_MIN(vs_prop_[x_id]) TTL_CTR_V);
					if (changed) {
						v_add_to_prop(vs_id_to_prop_, vs_prop_, x_id);
					}
				}
				if (V_MIN(vs_prop_[x_id]) != 0) {

					cl_v_del_gt_m(&changed, &vs_prop_[y_id], V_MIN(vs_prop_[y_id]) TTL_CTR_V);
					if (changed) {
						v_add_to_prop(vs_id_to_prop_, vs_prop_, y_id);
					}
				}
			}
		}

#if CL_CS_IGNORE
		cs_ignore[current_cs->c_id] = 1;
#endif
		return;
	}

	if (max == k) {
		for (i = 0; i < terms; i++) {
			CHECK_TTL(ttl_ctr, 93)
			x_id = vs_per_c_idx[i];
			y_id = vs_per_c_idx[terms + i];

			if (V_N_VALS(vs_prop_[x_id]) > 1) {
				if (V_MAX(vs_prop_[x_id]) != 0 && V_MAX(vs_prop_[y_id]) != 0) {

					cl_v_del_lt_m(&changed, &vs_prop_[x_id], V_MAX(vs_prop_[x_id]) TTL_CTR_V);
					if (changed) {
						v_add_to_prop(vs_id_to_prop_, vs_prop_, x_id);
					}

					cl_v_del_lt_m(&changed, &vs_prop_[y_id], V_MAX(vs_prop_[y_id]) TTL_CTR_V);
					if (changed) {
						v_add_to_prop(vs_id_to_prop_, vs_prop_, y_id);
					}
				}
			}
		}

#if CL_CS_IGNORE
		cs_ignore[current_cs->c_id] = 1;
#endif
	}
}

#if CS_R_SUM_PROD == 1
/*
 * Validate sum_prod constraint to be normally propagated, when reified
 * X . Y = k
 * vs_per_c_idx - vector with all constrained variables ID per constraint, per constraint ID order
 * vs_prop_ - all CSP variables with current step values
 * current_cs - constraint that should be propagated for the variable with prop_v_id ID
 * vs_id_to_prop_ - circular vector with the ids of the variables to propagate
 */
CUDA_FUNC void sum_prod_reif( CL_INTS_MEM int* vs_per_c_idx, CL_MEMORY VARS_PROP* vs_prop_, CL_CS_MEM cl_constr* current_cs, CL_MEMORY unsigned short* vs_id_to_prop_
		CS_IGNORE_FUNC TTL_CTR) {

	int terms = current_cs->n_c_vs / 2;
	int k = current_cs->constant_val;
	int x_id;
	int y_id;
	int min, max;
	bool all_singl = true;
	int i;

	// if the sum of the minimum of the products is greater than k
	min = 0;
	for (i = 0; i < terms; i++) {
		CHECK_TTL(ttl_ctr, 94)
		x_id = vs_per_c_idx[i];
		y_id = vs_per_c_idx[terms + i];

		min += V_MIN(vs_prop_[x_id]) * V_MIN(vs_prop_[y_id]);

		if (V_N_VALS(vs_prop_[x_id]) != 1) {
			all_singl = false;
		}

		if (min > k) {
			cl_v_bool_del_val_m(&vs_prop_[current_cs->reif_var_id], 1 TTL_CTR_V);
			v_add_to_prop(vs_id_to_prop_, vs_prop_, convert_int(current_cs->reif_var_id));

#if CL_CS_IGNORE
		cs_ignore[current_cs->c_id] = 1;
#endif
			return;
		}
	}

	if (all_singl && min == k) {
		cl_v_bool_del_val_m(&vs_prop_[current_cs->reif_var_id], 0 TTL_CTR_V);
		v_add_to_prop(vs_id_to_prop_, vs_prop_, convert_int(current_cs->reif_var_id));

#if CL_CS_IGNORE
		cs_ignore[current_cs->c_id] = 1;
#endif
		return;
	}

	// if the sum of the maximum of the products is lesser than k
	max = 0;
	for (i = 0; i < terms; i++) {
		CHECK_TTL(ttl_ctr, 95)
		x_id = vs_per_c_idx[i];
		y_id = vs_per_c_idx[terms + i];

		max += V_MAX(vs_prop_[x_id]) * V_MAX(vs_prop_[y_id]);
	}

	if (max < k) {
		cl_v_bool_del_val_m(&vs_prop_[current_cs->reif_var_id], 1 TTL_CTR_V);
		v_add_to_prop(vs_id_to_prop_, vs_prop_, convert_int(current_cs->reif_var_id));

#if CL_CS_IGNORE
		cs_ignore[current_cs->c_id] = 1;
#endif
	}
}

/*
 * Propagate the domain of the variable with the ID prop_v_id through all the other variables on the same c_numb ID sum_prod constraint
 * X . Y != k
 * vs_per_c_idx - vector with all constrained variables ID per constraint, per constraint ID order
 * vs_prop_ - all CSP variables with current step values
 * prop_v_id - variable ID to propagate
 * current_cs - constraint that should be propagated for the variable with prop_v_id ID
 * vs_id_to_prop_ - circular vector with the ids of the variables to propagate
 */
CUDA_FUNC void sum_prod_prop_opposite(CL_INTS_MEM int* vs_per_c_idx, CL_MEMORY VARS_PROP* vs_prop_, CL_CS_MEM cl_constr* current_cs, bool* prop_ok TTL_CTR) {

	int terms = current_cs->n_c_vs / 2;
	int k = current_cs->constant_val;
	int x_id;
	int y_id;
	int min, max;
	int i;

	// if the sum of the minimum of the products is equal to k
	min = 0;
	max = 0;
	for (i = 0; i < terms; i++) {
		CHECK_TTL(ttl_ctr, 228)
		x_id = vs_per_c_idx[i];
		y_id = vs_per_c_idx[terms + i];

		min += V_MIN(vs_prop_[x_id]) * V_MIN(vs_prop_[y_id]);
		max += V_MAX(vs_prop_[x_id]) * V_MAX(vs_prop_[y_id]);
	}

	if (min == max && max == k) {
		*prop_ok = 0;
		return;
	}
}

#endif

CUDA_FUNC void sum_prod_propagate(CL_INTS_MEM int* vs_per_c_idx, CL_MEMORY VARS_PROP* vs_prop_, CL_CS_MEM cl_constr* current_cs, CL_MEMORY unsigned short* vs_id_to_prop_,
		bool* prop_ok PROPAGATED_FUNC CS_IGNORE_FUNC TTL_CTR) {

#if CS_R_SUM_PROD == 0
	sum_prod_prop(vs_per_c_idx, vs_prop_, current_cs, vs_id_to_prop_, prop_ok CS_IGNORE_CALL TTL_CTR_V);
#if CL_STATS == 1
	*propagated = true;
#endif
#elif CS_R_SUM_PROD == 1
	if (current_cs->reified == 1) {
		if (V_N_VALS(vs_prop_[current_cs->reif_var_id]) > 1) {
			sum_prod_reif(vs_per_c_idx, vs_prop_, current_cs, vs_id_to_prop_ CS_IGNORE_CALL TTL_CTR_V);

		} else {
			if (V_MIN(vs_prop_[current_cs->reif_var_id]) == 1) {
				sum_prod_prop(vs_per_c_idx, vs_prop_, current_cs, vs_id_to_prop_, prop_ok CS_IGNORE_CALL TTL_CTR_V);
			} else {
				sum_prod_prop_opposite(vs_per_c_idx, vs_prop_, current_cs, prop_ok TTL_CTR_V);
			}
#if CL_STATS == 1
			*propagated = true;
#endif
		}
	} else {
		sum_prod_prop(vs_per_c_idx, vs_prop_, current_cs, vs_id_to_prop_, prop_ok CS_IGNORE_CALL TTL_CTR_V);
#if CL_STATS == 1
		*propagated = true;
#endif
	}
#endif
}

#endif