/* quantum.h: Header file for libquantum

   Copyright 2003-2013 Bjoern Butscher, Hendrik Weimer

   This file is part of libquantum

   libquantum is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published
   by the Free Software Foundation; either version 3 of the License,
   or (at your option) any later version.

   libquantum is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with libquantum; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA

*/

#ifndef __QUANTUM_H

#define __QUANTUM_H

#define COMPLEX_FLOAT @CF_TYPE@
#define MAX_UNSIGNED @MU_TYPE@

#define quantum_density_operation(function, rho, ...) \
do{ \
  int quantum_int; \
  for(quantum_int=0; quantum_int < rho.num; quantum_int++) \
    function(__VA_ARGS__, &rho.reg[quantum_int]); \
} while(0)

/* A ROWS x COLS matrix with complex elements */

struct quantum_matrix_struct {
  int rows;
  int cols;
  COMPLEX_FLOAT *t;
};

typedef struct quantum_matrix_struct quantum_matrix;

/* The quantum register */

struct quantum_reg_struct
{
  int width;    /* number of qubits in the qureg */
  int size;     /* number of non-zero vectors */
  int hashw;    /* width of the hash array */
  COMPLEX_FLOAT *amplitude;
  MAX_UNSIGNED *state;
  int *hash;
};

typedef struct quantum_reg_struct quantum_reg;

struct quantum_density_op_struct
{
  int num;          /* total number of state vectors */
  float *prob;      /* probabilities of the state vectors */
  quantum_reg *reg; /* state vectors */
};

typedef struct quantum_density_op_struct quantum_density_op;

enum {
  QUANTUM_SOLVER_LANCZOS,
  QUANTUM_SOLVER_LANCZOS_MODIFIED,
  QUANTUM_SOLVER_IMAGINARY_TIME
};

extern quantum_reg quantum_new_qureg(MAX_UNSIGNED initval, int width);
extern quantum_reg quantum_new_qureg_size(int n, int width);
extern quantum_reg quantum_new_qureg_sparse(int n, int width);
extern void quantum_delete_qureg(quantum_reg *reg);
extern void quantum_print_qureg(quantum_reg reg);
extern void quantum_addscratch(int bits, quantum_reg *reg);
extern void quantum_print_timeop(int width, void f(quantum_reg *));

extern void quantum_cnot(int control, int target, quantum_reg *reg);
extern void quantum_toffoli(int control1, int control2, int target, 
			    quantum_reg *reg);
extern void quantum_unbounded_toffoli(int controlling, quantum_reg *reg, ...);
extern void quantum_sigma_x(int target, quantum_reg *reg);
extern void quantum_sigma_y(int target, quantum_reg *reg);
extern void quantum_sigma_z(int target, quantum_reg *reg);
extern void quantum_gate1(int target, quantum_matrix m, quantum_reg *reg);
extern void quantum_gate2(int target1, int target2, quantum_matrix m, 
			  quantum_reg *reg);
extern void quantum_r_x(int target, float gamma, quantum_reg *reg);
extern void quantum_r_y(int target, float gamma, quantum_reg *reg);
extern void quantum_r_z(int target, float gamma, quantum_reg *reg);
extern void quantum_phase_scale(int target, float gamma, quantum_reg *reg);
extern void quantum_phase_kick(int target, float gamma, quantum_reg *reg);
extern void quantum_hadamard(int target, quantum_reg *reg);
extern void quantum_walsh(int width, quantum_reg *reg);
extern void quantum_cond_phase(int control, int target, quantum_reg *reg);
extern void quantum_cond_phase_inv(int control, int target, quantum_reg *reg);
extern void quantum_cond_phase_kick(int control, int target, float gamma, 
				    quantum_reg *reg);
extern void quantum_cond_phase_shift(int control, int target, float gamma, 
				    quantum_reg *reg);
extern int quantum_gate_counter(int inc);

extern void quantum_qft(int width, quantum_reg *reg);
extern void quantum_qft_inv(int width, quantum_reg *reg);

extern void quantum_exp_mod_n(int N, int x, int width_input, int width, 
			      quantum_reg *reg);

extern MAX_UNSIGNED quantum_measure(quantum_reg reg);
extern int quantum_bmeasure(int pos, quantum_reg *reg);
extern int quantum_bmeasure_bitpreserve(int pos, quantum_reg *reg);

extern quantum_matrix quantum_new_matrix(int cols, int rows);
extern void quantum_delete_matrix(quantum_matrix *m);
extern quantum_matrix quantum_mmult(quantum_matrix A, quantum_matrix B);

extern int quantum_ipow(int a, int b);
extern int quantum_gcd(int u, int v);
extern void quantum_cancel(int *a, int *b);
extern void quantum_frac_approx(int *a, int *b, int width);
extern int quantum_getwidth(int n);

extern double quantum_prob(COMPLEX_FLOAT a);

extern float quantum_get_decoherence();
extern void quantum_set_decoherence(float lambda);
extern void quantum_decohere(quantum_reg *reg);

extern quantum_reg quantum_matrix2qureg(quantum_matrix *m, int width);
extern quantum_matrix quantum_qureg2matrix(quantum_reg reg);
extern quantum_reg quantum_kronecker(quantum_reg *reg1, quantum_reg *reg2);
extern COMPLEX_FLOAT quantum_dot_product(quantum_reg *reg1, quantum_reg *reg2);
extern quantum_reg quantum_vectoradd(quantum_reg *reg1, quantum_reg *reg2);
extern void quantum_vectoradd_inplace(quantum_reg *reg1, quantum_reg *reg2);
extern quantum_reg quantum_matrix_qureg(quantum_reg A(MAX_UNSIGNED, double),
					double t, quantum_reg *reg, int flags);
extern void quantum_scalar_qureg(COMPLEX_FLOAT r, quantum_reg *reg);
extern void quantum_print_timeop(int width, void f(quantum_reg *));

extern void quantum_qec_encode(int type, int width, quantum_reg *reg);
extern void quantum_qec_decode(int type, int width, quantum_reg *reg);

extern const char * quantum_get_version();

extern void quantum_objcode_start();
extern void quantum_objcode_stop();
extern int quantum_objcode_write(char *file);
extern void quantum_objcode_run(char *file, quantum_reg *reg);

extern quantum_density_op quantum_new_density_op(int num, float *prob,
						 quantum_reg *reg);
extern quantum_density_op quantum_qureg2density_op(quantum_reg *reg);
extern void quantum_reduced_density_op(int pos, quantum_density_op *rho);
extern quantum_matrix quantum_density_matrix(quantum_density_op *rho);
extern void quantum_print_density_matrix(quantum_density_op *rho);
extern void quantum_delete_density_op(quantum_density_op *rho);
extern float quantum_purity(quantum_density_op *rho);

extern void *quantum_error_handler(void *f(int));
extern const char *quantum_strerr(int errno);
extern void quantum_error(int errno);

extern void quantum_rk4(quantum_reg *reg, double t, double dt, 
			quantum_reg H(MAX_UNSIGNED, double), int flags);
extern double quantum_rk4a(quantum_reg *reg, double t, double *dt, 
			   double epsilon, 
			   quantum_reg H(MAX_UNSIGNED, double), int flags);

extern void quantum_diag_time(double t, quantum_reg *reg0, quantum_reg *regt, 
			      quantum_reg *tmp1, quantum_reg *tmp2, 
			      quantum_matrix H, @RF_TYPE@ **w);


extern double quantum_groundstate(quantum_reg *reg, double epsilon, 
				  quantum_reg H(MAX_UNSIGNED, double), 
				  int solver, double stepsize);

#endif