/*
 * exactly_var.c
 *
 *  Created on: 13/03/2017
 *      Author: Pedro
 */

#ifndef __OPENCL_VERSION__

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

#include "exactly_var.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 exactly_var type and return the constraint ID
 * #{i | X[i] = k} = y
 * X_ids - vector with the ID of the variables that may contain the value of y
 * n_vs - maximum number of variables in X vector
 * c - number of variables in X that must contain the value of y
 * y_id - variable with the value that should be contained by the variables in X
 */
unsigned int c_exactly_var(unsigned int *X_ids, unsigned int n_vs, unsigned int c, unsigned int y_id) {
	unsigned int i;

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

	unsigned int *c_vs = malloc((n_vs + 1) * sizeof(unsigned int));

	for (i = 0; i < n_vs; i++) {
		c_vs[i] = X_ids[i];
	}
	c_vs[n_vs] = y_id;

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

	// pointers to this type of constraint functions
	CS[c_id].kind = EXACTLY_VAR;
	CS[c_id].check_sol_f = &exactly_var_check;
	CS[c_id].constant_val = (int) c;

	free(c_vs);

	return c_id;
}

/*
 * Creates a new constraint of the exactly_var type and return the constraint ID
 * #{i | X[i] = k} = y
 * X_ids - vector with the ID of the variables that may contain the value of y
 * n_vs - maximum number of variables in X vector
 * c - number of variables in X that must contain the value of y
 * y_id - variable with the value that should be contained by the variables in X
 * reif_v_id - ID of the reification variable
 */
unsigned int c_exactly_var_reif(unsigned int *X_ids, unsigned int n_vs, unsigned int c, unsigned int y_id, 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) {
			printf("\nConstraint EXACTLY_VAR_REIF makes model inconsistent at creation. No solution found.\n");

#if defined(WIN32) || defined(_WIN32) || defined(__WIN32) && !defined(__CYGWIN__)
			printf("\nPress any key to exit\n");
			int a = getchar();
#endif

			exit(0);
		}
	}

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

	unsigned int *c_vs = malloc((n_vs + 1) * sizeof(unsigned int));

	for (i = 0; i < n_vs; i++) {
		c_vs[i] = X_ids[i];
	}
	c_vs[n_vs] = y_id;

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

	// pointers to this type of constraint functions
	CS[c_id].kind = EXACTLY_VAR;
	CS[c_id].check_sol_f = &exactly_var_check;
	CS[c_id].constant_val = (int) c;

	free(c_vs);

	return c_id;
}

/*
 * Return true if the exactly_var constraint is respected or false if not
 * #{i | X[i] = k} = y
 * 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 exactly_var_check(constr *c, bool explored) {
	var **X = c->c_vs;
	var *x;
	var *y = c->c_vs[c->n_c_vs - 1];
	int k = c->constant_val;
	unsigned int set = 0;
	int i;

	if (!explored) {
		for (i = 0; i < c->n_c_vs; i++) {
			if (c->c_vs[i]->n_vals > 1) {
				return false;
			}
		}
	}

	if (c->reified && VS[c->reif_v_id].n_vals > 1) {
		if (explored) {
			fprintf(stderr, "\nError: Reification variable of constraint EXACTLY_VAR_REIF (%d) has 2 values.\n", c->c_id);
			return false;
		}
	}

	for (i = 0; i < c->n_c_vs - 1; i++) {
		x = X[i];

		if (x->min == k) {
			set++;
		}
	}

	if (((!c->reified || (c->reified && VS[c->reif_v_id].min == 1)) && set != y->min) || (c->reified && VS[c->reif_v_id].min == 0 && set == y->min)) {

		if (explored) {

			if (c->reified) {
				fprintf(stderr, "\nError: Constraint EXACTLY_VAR_REIF (%d) not respected:\n", c->c_id);
				fprintf(stderr, "Reif ID=%u -> minimum=%u, maximum=%u, number of values=%u\n\n", c->reif_v_id, b_get_min_val(&VS[c->reif_v_id].domain_b),
						b_get_max_val(&VS[c->reif_v_id].domain_b), b_cnt_vals(&VS[c->reif_v_id].domain_b));

			} else {
				fprintf(stderr, "\nError: Constraint EXACTLY_VAR (%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_EXACTLY_VAR == 1
/*
 * Propagate the domain of the variable with the ID prop_v_id through all the other variables on the same c_numb ID exactly_var constraint
 * #{i | X[i] = k} = y
 * 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
 * prop_ok - will be set to 1 or 0 if the constraint is respected or not
 */
CUDA_FUNC void exactly_var_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 y_id = vs_per_c_idx[current_cs->n_c_vs - 1];
	int k = current_cs->constant_val;
	int x_id;
	int set = 0;
	int possible = 0;
	bool contains;
	bool changed = 0;
	int i;

	for (i = 0; i < current_cs->n_c_vs - 1; i++) {
		CHECK_TTL(ttl_ctr, 61)
		x_id = vs_per_c_idx[i];

		// if more than c variables are already set to k, return 0
		if (V_N_VALS(vs_prop_[x_id]) == 1 && V_MIN(vs_prop_[x_id]) == k) {
			if (++set > V_MAX(vs_prop_[y_id])) {
				*prop_ok = 0;
				return;
			}
			// number of variables that may be set to k
		} else {
			cl_v_contains_val_m(&contains, &vs_prop_[x_id], k TTL_CTR_V);
			if (contains) {
				possible++;
			}
		}
	}

	// if there are not enough variables to set to k
	if (set + possible < V_MIN(vs_prop_[y_id])) {
		*prop_ok = 0;
		return;
	}

	if (V_N_VALS(vs_prop_[y_id]) == 1) {

		// if the sum of the variables that contain k are y, assign all of them to k
		if (set + possible == V_MIN(vs_prop_[y_id])) {

			for (i = 0; possible > 0; i++) {
				CHECK_TTL(ttl_ctr, 62)

				x_id = vs_per_c_idx[i];
				if (V_N_VALS(vs_prop_[x_id]) > 1) {

					cl_v_contains_val_m(&contains, &vs_prop_[x_id], k TTL_CTR_V);
					if (contains) {
						cl_v_del_all_except_val_m(&changed, &vs_prop_[x_id], k TTL_CTR_V);
						possible--;
						v_add_to_prop(vs_id_to_prop_, vs_prop_, x_id);
					}
				}
			}

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

		// if all the variables already assigned to k are y, remove k from the other variables
		if (set == V_MAX(vs_prop_[y_id])) {

			for (i = 0; possible > 0; i++) {
				CHECK_TTL(ttl_ctr, 63)

				x_id = vs_per_c_idx[i];
				if (V_N_VALS(vs_prop_[x_id]) > 1) {

					cl_v_del_all_except_val_m(&changed, &vs_prop_[x_id], k TTL_CTR_V);
					if (changed) {
						possible--;
						v_add_to_prop(vs_id_to_prop_, vs_prop_, x_id);
					}
				}
			}
#if CL_CS_IGNORE
			cs_ignore[current_cs->c_id] = 1;
#endif
		}
		return;
	}

	// if prop_v_id != y_id or y is not singleton
	// if the sum of the variables that contain k are min(y), assign all of them to k
	// and remove all values except min from y
	if (set + possible == V_MIN(vs_prop_[y_id])) {

		for (i = 0; possible > 0; i++) {
			CHECK_TTL(ttl_ctr, 65)

			x_id = vs_per_c_idx[i];
			if (V_N_VALS(vs_prop_[x_id]) > 1) {

				cl_v_contains_val_m(&contains, &vs_prop_[x_id], k TTL_CTR_V);
				if (contains) {
					cl_v_del_all_except_val_m(&changed, &vs_prop_[x_id], k TTL_CTR_V);
					possible--;
					v_add_to_prop(vs_id_to_prop_, vs_prop_, x_id);
				}
			}
		}
		cl_v_del_all_except_val_m(&changed, &vs_prop_[y_id], V_MIN(vs_prop_[y_id]) TTL_CTR_V);
		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 all the variables already assigned to k are y max, remove k from the other variables
	if (set == V_MAX(vs_prop_[y_id])) {

		for (i = 0; possible > 0; i++) {
			CHECK_TTL(ttl_ctr, 66)

			x_id = vs_per_c_idx[i];
			if (V_N_VALS(vs_prop_[x_id]) > 1) {

				cl_v_del_val_m(&changed, &vs_prop_[x_id], k TTL_CTR_V);
				if (changed) {
					possible--;
					v_add_to_prop(vs_id_to_prop_, vs_prop_, x_id);
				}
			}
		}
		cl_v_del_all_except_val_m(&changed, &vs_prop_[y_id], V_MAX(vs_prop_[y_id]) TTL_CTR_V);
		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;
	}

	// remove from y the value that are not capable of corresponding to the number of x variables that contain k
	if (set > V_MIN(vs_prop_[y_id])) {
		cl_v_del_lt_m(&changed, &vs_prop_[y_id], set TTL_CTR_V);

		if (changed) {
			v_add_to_prop(vs_id_to_prop_, vs_prop_, y_id);
		}
	}
	if (set + possible < V_MAX(vs_prop_[y_id])) {
		cl_v_del_gt_m(&changed, &vs_prop_[y_id], set + possible TTL_CTR_V);

		if (changed) {
			v_add_to_prop(vs_id_to_prop_, vs_prop_, y_id);
		}
	}
}

#if CS_R_EXACTLY_VAR == 1
/*
 * Validate exactly_var constraint to be normally propagated, when reified
 * #{i | X[i] = k} = y
 * 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 exactly_var_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 y_id = vs_per_c_idx[current_cs->n_c_vs - 1];
	int k = current_cs->constant_val;
	int x_id;
	int set = 0;
	int possible = 0;
	bool contains;
	int i;

	for (i = 0; i < current_cs->n_c_vs - 1; i++) {
		CHECK_TTL(ttl_ctr, 67)
		x_id = vs_per_c_idx[i];

		// if more than c variables are already set to k, return 0
		if (V_N_VALS(vs_prop_[x_id]) == 1 && V_MIN(vs_prop_[x_id]) == k) {
			if (++set > V_MAX(vs_prop_[y_id])) {
				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;
			}
			// number of variables that may be set to k
		} else {
			cl_v_contains_val_m(&contains, &vs_prop_[x_id], k TTL_CTR_V);
			if (contains) {
				possible++;
			}
		}
	}

	// if there are not enough variables to set to k
	if (set + possible < V_MIN(vs_prop_[y_id])) {
		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;
	}

	// constraint already fixed
	if (V_N_VALS(vs_prop_[y_id]) == 1 && set == V_MIN(vs_prop_[y_id]) && possible == 0) {
		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
	}
}

/*
 * Propagate the domain of the variable with the ID prop_v_id through all the other variables on the same c_numb ID exactly_var opposite constraint
 * #{i | X[i] = k} != y
 * 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 exactly_var_prop_opposite( 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 y_id = vs_per_c_idx[current_cs->n_c_vs - 1];
	int k = current_cs->constant_val;
	int x_id;
	int set = 0;
	int possible = 0;
	bool contains;
	bool changed = 0;
	int i;

	for (i = 0; i < current_cs->n_c_vs - 1; i++) {
		CHECK_TTL(ttl_ctr, 217)
		x_id = vs_per_c_idx[i];

		// if more than c variables are already set to k, return 0
		if (V_N_VALS(vs_prop_[x_id]) == 1 && V_MIN(vs_prop_[x_id]) == k) {
			if (++set > V_MAX(vs_prop_[y_id])) {
				return;
			}
			// number of variables that may be set to k
		} else {
			cl_v_contains_val_m(&contains, &vs_prop_[x_id], k TTL_CTR_V);
			if (contains) {
				possible++;
			}
		}
	}

	// if there are not enough variables to set to k
	if (set + possible < V_MIN(vs_prop_[y_id])) {

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

	if (V_N_VALS(vs_prop_[y_id]) == 1) {

		// if the sum of the variables that are assigned with k are y, and that contain k are y+1, assign the one to k
		if (set == V_MIN(vs_prop_[y_id]) && possible == 1) {

			for (i = 0; possible > 0; i++) {
				CHECK_TTL(ttl_ctr, 216)

				x_id = vs_per_c_idx[i];
				if (V_N_VALS(vs_prop_[x_id]) > 1) {

					cl_v_contains_val_m(&contains, &vs_prop_[x_id], k TTL_CTR_V);
					if (contains) {
						cl_v_del_all_except_val_m(&changed, &vs_prop_[x_id], k TTL_CTR_V);
						possible--;
						v_add_to_prop(vs_id_to_prop_, vs_prop_, x_id);
					}
				}
			}
#if CL_CS_IGNORE
			cs_ignore[current_cs->c_id] = 1;
#endif
		}
	}
}

#endif

/*
 * Decides the propagator to call for this constraint
 * 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
 * prop_ok - will be set to 1 or 0 if the constraint is respected or not
 */
CUDA_FUNC void exactly_var_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_EXACTLY_VAR == 0
	exactly_var_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_EXACTLY_VAR == 1
	if (current_cs->reified == 1) {
		if (V_N_VALS(vs_prop_[current_cs->reif_var_id]) > 1) {
			exactly_var_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) {
				exactly_var_prop(vs_per_c_idx, vs_prop_, current_cs, vs_id_to_prop_, prop_ok CS_IGNORE_CALL TTL_CTR_V);
			} else {
				exactly_var_prop_opposite(vs_per_c_idx, vs_prop_, current_cs, vs_id_to_prop_ CS_IGNORE_CALL TTL_CTR_V);
			}
#if CL_STATS == 1
			*propagated = true;
#endif
		}
	} else {
		exactly_var_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