/*
 * CS5600 University of Utah
 * Charles McGarvey
 * mcgarvey@eng.utah.edu
 */

#ifndef _COMMON_H_
#define _COMMON_H_

#include <math.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "config.h"


/*
 * Define a keyword for use while defining small and fast functions.
 */
#if EXTRA_INLINE
#define INLINE_MAYBE static inline
#else
#define INLINE_MAYBE static
#endif


/*
 * Define a type for scalar values, either float or double.
 */
#if DOUBLE_FLOAT
typedef double scal_t;
#define SCALAR_SIZE 8
#define S(K) K
#define scal_floor  floor
#define scal_ceil   ceil
#define scal_min    fmin
#define scal_max    fmax
#define scal_abs    fabs
#define scal_pow    pow
#define scal_sqrt   sqrt
#define scal_sin    sin
#define scal_cos    cos
#define scal_tan    tan
#define scal_asin   asin
#define scal_acos   acos
#define scal_atan   atan
#else
typedef float scal_t;
#define SCALAR_SIZE 4
#define S(K) K##f
#define scal_floor  floorf
#define scal_ceil   ceilf
#define scal_min    fminf
#define scal_max    fmaxf
#define scal_abs    fabsf
#define scal_pow    powf
#define scal_sqrt   sqrtf
#define scal_sin    sinf
#define scal_cos    cosf
#define scal_tan    tanf
#define scal_asin   asinf
#define scal_acos   acosf
#define scal_atan   atanf
#endif

#define scal_min2(A,B,C) scal_min(scal_min(A,B),C)
#define scal_max2(A,B,C) scal_max(scal_max(A,B),C)

#define SCAL_EPSILON (S(0.000001))

/*
 * Check if two scalars are mostly equal, given a margin of error.
 */
INLINE_MAYBE
bool scal_isequal2(scal_t a, scal_t b, scal_t e)
{
    return scal_abs(a -b) < e;
}

/*
 * Check if two scalars are mostly equal.
 */
INLINE_MAYBE
bool scal_isequal(scal_t a, scal_t b)
{
    return scal_isequal2(a, b, SCAL_EPSILON);
}

/*
 * Clamp a scalar between two values.
 */
INLINE_MAYBE
scal_t scal_clamp(scal_t s, scal_t min, scal_t max)
{
    if (s < min) {
        return min;
    }
    if (max < s) {
        return max;
    }
    return s;
}


/*
 * Define min and max functions for integers.
 */
INLINE_MAYBE
int imin(int a, int b)
{
    return a < b ? a : b;
}
INLINE_MAYBE
int imax(int a, int b)
{
    return a < b ? b : a;
}


/*
 * Define some macros for packing and unpacking bytes to and from larger ints.
 */
#define PACK(W,N,B) (((B) << (8 * (N))) | ((W) & ~(0xff << (8 * (N)))))
#define UNPACK(W,N) ((uint8_t)((W) >> (8 * (N))) & 0xff)


/*
 * Try to execute a statement and print a status message.  If the statement
 * resolves to 0, it is considered to have succeeded; any other evaluation is
 * an error condition and an abort(3) occurs.
 * return.
 */
#if VERBOSITY >= 1
#define TRY_DO(L, K, ARGS...) \
printf("* " L "... ", ##ARGS); \
fflush(stdout); \
if ((K) == 0) printf("done!\n"); \
else abort()
#else
#define TRY_DO(L, K, ARGS...) \
if ((K) != 0) abort()
#endif


/*
 * Declare a type of destructor functions.
 */
typedef void (*dtor_t)(void*);
#define DTOR(A) (dtor_t)(A)


/*
 * Allocate a block of memory of a certain size.  This follows the semantics
 * of malloc(3), except it will never return NULL and will abort(3) if the
 * memory could not be allocated.
 */
void* mem_alloc(size_t size);

/*
 * Change the size of a block of memory.  This follows the semantics of
 * realloc(3), except it will never return NULL and will abort(3) if the
 * memory could not be allocated.
 */
void* mem_realloc(void* mem, size_t size);

/*
 * Deallocate a block of memory previously allocated by mem_alloc or malloc(3)
 * and friends.  This is essentially just a call to free(3).
 */
void mem_free(void* mem);

/*
 * Set a function to call if either mem_alloc or mem_realloc fails, or NULL if
 * no callback should be called.  The callback takes the same arguments as
 * realloc(3) and may try to fulfill the request.  The return value of the
 * callback function will be returned from the allocation function and must be
 * a valid pointer to an allocated block of memory.  The callback function
 * should not call mem_alloc or mem_realloc and must not return if a block of
 * memory could not be allocated.
 */
void mem_set_fn(void* (*fn)(void*, size_t));

/*
 * Get the number of blocks currently allocated with either mem_alloc or
 * mem_realloc.  This number should be zero at the end of a process running
 * this program.
 */
int mem_blocks();


/*
 * Duplicate a string; like the non-standard strdup(3) but uses mem_alloc.
 * The result needs to be freed with mem_free.
 */
INLINE_MAYBE
char* mem_strdup(const char* str)
{
    size_t size = strlen(str) + 1;
    return (char*)memcpy(mem_alloc(size), str, size);
}

/*
 * Get an allocated string made up of two strings concatenated together.
 * The result needs to be freed with mem_free.
 */
INLINE_MAYBE
char* mem_strcat(const char* str1, const char* str2)
{
    size_t size1 = strlen(str1);
    size_t size2 = strlen(str2);
    char* str = (char*)mem_alloc(size1 + size2 + 1);
    memcpy(str + size1, str2, size2 + 1);
    return memcpy(str, str1, size1);
}


/*
 * Cut a string short at the last matching character.  The string will be
 * modified if the character was matched.  Either way, str is returned.
 */
INLINE_MAYBE
char* strcut(char* str, int c)
{
    char* ptr = strrchr(str, c);
    if (ptr != NULL) {
        *ptr = '\0';
    }
    return str;
}

/*
 * Trim white space off of the right side of a string.
 */
void rtrim(char *str);

/*
 * Trim white space off of the left side of a string.
 */
void ltrim(char *str);

/*
 * Trim white space off of both sides of a string.
 */
INLINE_MAYBE
void trim(char *str)
{
    rtrim(str);
    ltrim(str);
}


/*
 * Initialize the timer.
 */
void timer_start();

/*
 * Stop the timer and return how many microseconds passed after
 * initialization.
 */
long timer_stop();


#endif // _COMMON_H_