/*
 * Unit test for timespec's
 *
 * This file is Copyright (c) 2010 by the GPSD project
 * SPDX-License-Identifier: BSD-2-clause
 *
 */
#include <stdlib.h>
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>   /* required by C99, for int32_t */
#include <string.h>
#include <math.h>
#include <unistd.h>

#include "../compiler.h"
#include "../revision.h"
#include "../ppsthread.h"
#include "../timespec.h"

#define TS_ZERO         {0,0}
#define TS_ZERO_ONE     {0,1}
#define TS_ZERO_TWO     {0,2}
#define TS_ZERO_TREES   {0,333333333}
#define TS_ZERO_SIXS7   {0,666666667}
#define TS_ZERO_NINES   {0,999999999}
#define TS_ONE          {1,0}
#define TS_ONE_ONE      {1,1}
#define TS_TWO          {2,0}
#define TS_N_ZERO_ONE   {0,-1}
#define TS_N_ZERO_TWO   {0,-2}
#define TS_N_ZERO_TREES {0,-333333333}
#define TS_N_ZERO_NINES {0,-999999999}
#define TS_N_ONE        {-1,0}

/* minutes, hours, days */
#define TS_ONEM         {60,0}			/* one minute */
#define TS_ONEM_TREES   {60,333333333}		/* one minute, threes */
#define TS_ONEM_NINES   {60,999999999}		/* one minute, nines */
#define TS_ONEH         {3600,0}		/* one hour */
#define TS_ONEH_TREES   {3600,333333333}	/* one hour, threes */
#define TS_ONEH_NINES   {3600,999999999}	/* one hour, nines */
#define TS_ONED         {86400,0}		/* one day */
#define TS_ONED_TREES   {86400,333333333}	/* one day, threes */
#define TS_ONED_NINES   {86400,999999999}	/* one day, nines */
#define TS_N_ONEM       {-60,0}			/* negative one minute */
#define TS_N_ONEH       {-3600,0}		/* negative one hour */
#define TS_N_ONED       {-86400,0}		/* negative one day */

/* Dec 31, 23:59 2037 GMT */
#define TS_2037         {2145916799, 0}
#define TS_2037_ONE     {2145916799, 1}
#define TS_2037_TWO     {2145916799, 2}
#define TS_2037_X       {2145916799, 123456789}
#define TS_2037_TREES   {2145916799, 333333333}
#define TS_2037_SIXS7   {2145916799, 666666667}
#define TS_2037_NINES   {2145916799, 999999999}
#define TS_N_2037_TREES {-2145916799, -333333333}
#define TS_N_2037_NINES {-2145916799, -999999999}

/* a 32 bit copy of timespec_diff_ns() to force a 32 bit int */
/* used to demonstrate how 32 bit longs can not work */
#define timespec_diff_ns32(x, y) \
 (int32_t)((int32_t)(((x).tv_sec-(y).tv_sec)*NS_IN_SEC)+(x).tv_nsec-(y).tv_nsec)

/* a 64 bit copy of timespec_diff_ns() to force a 64 bit int */
/* used to demonstrate how 64 bit long longs can work */
#define timespec_diff_ns64(x, y) \
 (int64_t)((int64_t)(((x).tv_sec-(y).tv_sec)*NS_IN_SEC)+(x).tv_nsec-(y).tv_nsec)

/* convert long long ns to a timespec */
#define ns_to_timespec(ts, ns) \
	(ts).tv_sec  = ns / NS_IN_SEC; \
	(ts).tv_nsec = ns % NS_IN_SEC;

/* convert double to a timespec */
static inline void d_str( const double d, char *buf, size_t buf_size)
{
    /* convert to string */
    if ( 0 <= d ) {
	(void) snprintf( buf, buf_size, " %.9f", d);
    } else {
	(void) snprintf( buf, buf_size, "%.9f", d);
    }
}

/* a - b should be c */
struct subtract_test {
	struct timespec a;	
	struct timespec b;
	struct timespec c;
	bool last;  		/* last test marker */
};

struct subtract_test subtract_tests[] = {
	{ TS_ZERO,        TS_ZERO,        TS_ZERO,         0},
	{ TS_ONE,         TS_ONE,         TS_ZERO,         0},
	{ TS_ZERO_ONE,    TS_ZERO_ONE,    TS_ZERO,         0},
	{ TS_ONE_ONE,     TS_ONE_ONE,     TS_ZERO,         0},
	{ TS_N_ONE,       TS_N_ONE,       TS_ZERO,         0},
	{ TS_N_ZERO_ONE,  TS_N_ZERO_ONE,  TS_ZERO,         0},
	{ TS_ZERO_TREES,  TS_ZERO_TREES,  TS_ZERO,         0},
	{ TS_ZERO_NINES,  TS_ZERO_NINES,  TS_ZERO,         0},
	{ TS_ZERO_TREES,  TS_ZERO,        TS_ZERO_TREES,   0},
	{ TS_ZERO,        TS_N_ONE,       TS_ONE,          0},
	{ TS_ONE,         TS_ZERO,        TS_ONE,          0},
	{ TS_TWO,         TS_ONE,         TS_ONE,          0},
	{ TS_ONE_ONE,     TS_ONE,         TS_ZERO_ONE,     0},
	{ TS_ONE,         TS_ZERO_TREES,  TS_ZERO_SIXS7,   0},
	{ TS_ONE,         TS_ZERO_NINES,  TS_ZERO_ONE,     0},
	{ TS_ZERO_TWO,    TS_ZERO_ONE,    TS_ZERO_ONE,     0},
	{ TS_2037_ONE,    TS_2037,        TS_ZERO_ONE,     0},
	{ TS_ONE_ONE,     TS_ZERO_NINES,  TS_ZERO_TWO,     0},
	{ TS_ONEM,        TS_ZERO,        TS_ONEM,         0},
	{ TS_ONEM_TREES,  TS_ZERO,        TS_ONEM_TREES,   0},
	{ TS_ONEM_NINES,  TS_ZERO,        TS_ONEM_NINES,   0},
	{ TS_ZERO,        TS_ONEM,        TS_N_ONEM,       0},
	{ TS_ONEH,        TS_ZERO,        TS_ONEH,         0},
	{ TS_ONEH_TREES,  TS_ZERO,        TS_ONEH_TREES,   0},
	{ TS_ONEH_NINES,  TS_ZERO,        TS_ONEH_NINES,   0},
	{ TS_ZERO,        TS_ONEH,        TS_N_ONEH,       0},
	{ TS_ONED,        TS_ZERO,        TS_ONED,         0},
	{ TS_ONED_TREES,  TS_ZERO,        TS_ONED_TREES,   0},
	{ TS_ONED_NINES,  TS_ZERO,        TS_ONED_NINES,   0},
	{ TS_ZERO,        TS_ONED,        TS_N_ONED,       0},
	{ TS_2037_NINES,  TS_2037,        TS_ZERO_NINES,   0},
	{ TS_2037_TREES,  TS_ZERO,        TS_2037_TREES,   0},
	{ TS_2037_SIXS7,  TS_2037,        TS_ZERO_SIXS7,   0},
	{ TS_2037_TREES,  TS_2037,        TS_ZERO_TREES,   0},
	{ TS_2037_NINES,  TS_ZERO,        TS_2037_NINES,   0},
	{ TS_ZERO,        TS_ONE,         TS_N_ONE,        0},
	{ TS_ONE,         TS_TWO,         TS_N_ONE,        0},
	{ TS_ZERO,        TS_ZERO_ONE,    TS_N_ZERO_ONE,   0},
	{ TS_ONE,         TS_ONE_ONE,     TS_N_ZERO_ONE,   0},
	{ TS_ZERO_ONE,    TS_ZERO_TWO,    TS_N_ZERO_ONE,   0},
	{ TS_2037,        TS_2037_ONE,    TS_N_ZERO_ONE,   0},
	{ TS_ZERO_NINES,  TS_ONE_ONE,     TS_N_ZERO_TWO,   0},
	{ TS_2037,        TS_2037_NINES,  TS_N_ZERO_NINES, 0},
	{ TS_ZERO,        TS_2037_NINES,  TS_N_2037_NINES, 1},
};

typedef struct format_test {
	struct timespec input;
	char *expected;
	bool last;
} format_test_t;

struct format_test format_tests[] = {
	{ TS_ZERO,         " 0.000000000", 0},
	{ TS_ZERO_ONE,     " 0.000000001", 0},
	{ TS_ZERO_TWO,     " 0.000000002", 0},
	{ TS_ZERO_NINES,   " 0.999999999", 0},
	{ TS_ONE,          " 1.000000000", 0},
	{ TS_ONE_ONE,      " 1.000000001", 0},
	{ TS_TWO,          " 2.000000000", 0},
	{ TS_N_ZERO_ONE,   "-0.000000001", 0},
	{ TS_N_ZERO_TWO,   "-0.000000002", 0},
	{ TS_N_ZERO_NINES, "-0.999999999", 0},
	{ TS_N_ONE,        "-1.000000000", 0},
	{ TS_ONEM,         " 60.000000000", 0},
	{ TS_ONEM_TREES,   " 60.333333333", 0},
	{ TS_ONEH,         " 3600.000000000", 0},
	{ TS_ONEH_TREES,   " 3600.333333333", 0},
	{ TS_ONED,         " 86400.000000000", 0},
	{ TS_ONED_TREES,   " 86400.333333333", 0},
	{ TS_N_ONEM,        "-60.000000000", 0},
	{ TS_N_ONEH,        "-3600.000000000", 0},
	{ TS_N_ONED,        "-86400.000000000", 0},
	{ { -1, 1},        "-1.000000001", 0},
	{ { -1, -1},       "-1.000000001", 0},
	{ TS_2037,         " 2145916799.000000000", 0},
	{ TS_2037_ONE,     " 2145916799.000000001", 0},
	{ TS_2037_TREES,   " 2145916799.333333333", 1},
	{ TS_2037_NINES,   " 2145916799.999999999", 1},
};

/*
 * test subtractions using native timespec math: TS_SUB()
 *
 */
static int test_ts_subtract( int verbose )
{
    struct subtract_test *p = subtract_tests;
    int fail_count = 0;

    while ( 1 ) {
	char buf_a[TIMESPEC_LEN];
	char buf_b[TIMESPEC_LEN];
	char buf_c[TIMESPEC_LEN];
	char buf_r[TIMESPEC_LEN];
	struct timespec r;

        TS_SUB(&r, &p->a, &p->b);
        timespec_str( &p->a, buf_a, sizeof(buf_a) );
        timespec_str( &p->b, buf_b, sizeof(buf_b) );
        timespec_str( &p->c, buf_c, sizeof(buf_c) );
        timespec_str( &r,    buf_r, sizeof(buf_r) );
	if ( (p->c.tv_sec != r.tv_sec) || (p->c.tv_nsec != r.tv_nsec) ) {
		printf("%21s - %21s = %21s, FAIL s/b %21s\n",
		buf_a, buf_b, buf_r, buf_c);
		fail_count++;
	} else if ( verbose ) {
		printf("%21s - %21s = %21s\n", buf_a, buf_b, buf_r);
	}
		
	
	if ( p->last ) {
		break;
	}
	p++;
    };

    if ( fail_count ) {
	printf("timespec subtract test failed %d tests\n", fail_count );
    } else {
	puts("timespec subtract test succeeded\n");
    }
    return fail_count;
}

/*
 * test subtractions using timespec_diff_ns()
 *
 */
static int test_ns_subtract( int verbose )
{
    struct subtract_test *p = subtract_tests;
    int fail_count = 0;

    while ( 1 ) {
	char buf_a[TIMESPEC_LEN];
	char buf_b[TIMESPEC_LEN];
	char buf_c[TIMESPEC_LEN];
	char buf_r[TIMESPEC_LEN];
	struct timespec r;
	long long r_ns;

        r_ns = timespec_diff_ns(p->a, p->b);
        timespec_str( &p->a, buf_a, sizeof(buf_a) );
        timespec_str( &p->b, buf_b, sizeof(buf_b) );
        timespec_str( &p->c, buf_c, sizeof(buf_c) );
	ns_to_timespec( r, r_ns);
        timespec_str( &r,    buf_r, sizeof(buf_r) );
	if ( (p->c.tv_sec != r.tv_sec) || (p->c.tv_nsec != r.tv_nsec) ) {
		printf("%21s - %21s = %21s, FAIL s/b %21s\n",
			buf_a, buf_b, buf_r, buf_c);
		fail_count++;
	} else if ( verbose ) {
		printf("%21s - %21s = %21s\n", buf_a, buf_b, buf_r);
	}
		
	
	if ( p->last ) {
		break;
	}
	p++;
    };

    if ( fail_count ) {
	printf("ns subtract test failed %d tests\n", fail_count );
    } else {
	puts("ns subtract test succeeded\n");
    }
    return fail_count;
}

static int test_format(int verbose )
{
    format_test_t *p = format_tests;
    int fail_count = 0;

    while ( 1 ) {
	char buf[TIMESPEC_LEN];
	int fail;

        timespec_str( &p->input, buf, sizeof(buf) );
	fail = strncmp( buf, p->expected, TIMESPEC_LEN);
	if ( fail ) {
		printf("%21s, FAIL s/b: %21s\n", buf,  p->expected);
		fail_count++;
	} else if ( verbose )  {
		printf("%21s\n", buf);
	}
	
	if ( p->last ) {
		break;
	}
	p++;
    };

    if ( fail_count ) {
	printf("timespec_str test failed %d tests\n", fail_count );
    } else {
	puts("timespec_str test succeeded\n");
    }
    return fail_count;
}

static int ex_subtract_float( void )
{
    struct subtract_test *p = subtract_tests;
    int fail_count = 0;

    printf( "\n\nsubtract test examples using doubles,floats,longs:\n"
            " ts:  TS_SUB()\n"
            " l:   timespec_to_ns() math\n"
            " l32: timespec_to_ns() math with 32 bit long\n"
            " l64: timespec_to_ns() math with 64 bit long\n"
            " f:   float math\n"
            " d:   double float math\n"
	    "\n");

    while ( 1 ) {
	char buf_a[TIMESPEC_LEN];
	char buf_b[TIMESPEC_LEN];
	char buf_c[TIMESPEC_LEN];
	char buf_r[TIMESPEC_LEN];
	char buf_l[TIMESPEC_LEN];
	char buf_l32[TIMESPEC_LEN];
	char buf_l64[TIMESPEC_LEN];
	char buf_f[TIMESPEC_LEN];
	char buf_d[TIMESPEC_LEN];
	struct timespec ts_r;
	struct timespec ts_l;
	struct timespec ts_l32;
	struct timespec ts_l64;
	float f_a, f_b, f_r;
	double d_a, d_b, d_r;
	long long l;
	int32_t l32;  /* simulate a 32 bit long */
	int64_t l64;  /* simulate a 64 bit long */
	const char *fail_ts = "";
	const char *fail_l = "";
	const char *fail_l32 = "";
	const char *fail_l64 = "";
	const char *fail_f = "";
	const char *fail_d = "";

	/* timespec math */
        TS_SUB(&ts_r, &p->a, &p->b);

	/* float math */
	f_a = TSTONS( &p->a );
	f_b = TSTONS( &p->b );
	f_r = f_a - f_b;

	/* double float math */
	d_a = TSTONS( &p->a );
	d_b = TSTONS( &p->b );
	d_r = d_a - d_b;

	/* long math */
	l = timespec_diff_ns( p->a, p->b);
	l32 = timespec_diff_ns32( p->a, p->b);
	l64 = timespec_diff_ns64( p->a, p->b);

	/* now convert to strings */
        timespec_str( &p->a, buf_a, sizeof(buf_a) );
        timespec_str( &p->b, buf_b, sizeof(buf_b) );
        timespec_str( &p->c, buf_c, sizeof(buf_c) );
        timespec_str( &ts_r, buf_r, sizeof(buf_r) );

	ns_to_timespec( ts_l, l );
	timespec_str( &ts_l, buf_l, sizeof(buf_l) );
	ns_to_timespec( ts_l32, l32 );
	timespec_str( &ts_l32, buf_l32, sizeof(buf_l32) );
	ns_to_timespec( ts_l64, l64);
	timespec_str( &ts_l64, buf_l64, sizeof(buf_l64) );
	d_str( f_r, buf_f, sizeof(buf_f) );
	d_str( d_r, buf_d, sizeof(buf_d) );

	/* test strings */
	if ( strcmp( buf_r, buf_c) ) {
	    fail_ts = "FAIL";
            fail_count++;
	}
	if ( strcmp( buf_l, buf_c) ) {
	    fail_l = "FAIL";
            fail_count++;
	}
	if ( strcmp( buf_l32, buf_c) ) {
	    fail_l32 = "FAIL";
            fail_count++;
	}
	if ( strcmp( buf_l64, buf_c) ) {
	    fail_l64 = "FAIL";
            fail_count++;
	}
	if ( strcmp( buf_f, buf_c) ) {
	    fail_f = "FAIL";
            fail_count++;
	}
	if ( strcmp( buf_d, buf_c) ) {
	    fail_d = "FAIL";
            fail_count++;
	}
	printf("ts:  %21s - %21s = %21s %s\n"
	       "l;   %21s - %21s = %21lld %s\n"
	       "l32; %21s - %21s = %21lld %s\n"
	       "l64; %21s - %21s = %21lld %s\n"
	       "f;   %21.9f - %21.9f = %21.9f %s\n"
	       "d;   %21.9f - %21.9f = %21.9f %s\n"
	       "\n",
		buf_a, buf_b, buf_r, fail_ts,
		buf_a, buf_b, l, fail_l,
		buf_a, buf_b, (long long)l32, fail_l32,
		buf_a, buf_b, (long long)l64, fail_l64,
		f_a, f_b, f_r, fail_f,
		d_a, d_b, d_r, fail_d);
		
	
	if ( p->last ) {
		break;
	}
	p++;
    };

    if ( fail_count ) {
	printf("subtract test failed %d tests\n", fail_count );
    } else {
	puts("subtract test succeeded\n");
    }
    return fail_count;
}


/*
 * show examples of how integers and floats fail
 *
 */
static void ex_precision(void)
{
	format_test_t *p = format_tests;

	puts( "\n\n  Simple conversion examples\n\n"
		"ts:  timespec\n"
		"l32: 32 bit long\n"
		"l64: 64 bit long\n"
		"f:   float\n"
		"d:   double\n\n");

	while ( 1 ) {
	    float f;
	    double d;
	    int32_t l32;
	    int64_t l64;
	    char buf_ts[TIMESPEC_LEN];
	    char buf_l32[TIMESPEC_LEN];
	    char buf_l64[TIMESPEC_LEN];
	    char buf_f[TIMESPEC_LEN];
	    char buf_d[TIMESPEC_LEN];
	    const char *fail_ts = "";
	    const char *fail_l32 = "";
	    const char *fail_l64 = "";
	    const char *fail_f = "";
	    const char *fail_d = "";

	    struct timespec *v = &(p->input);
	    struct timespec ts_l32;
	    struct timespec ts_l64;


	    /* convert to test size */
	    l32 = (int32_t)(v->tv_sec * NS_IN_SEC)+(int32_t)v->tv_nsec;
	    l64 = (int64_t)(v->tv_sec * NS_IN_SEC)+(int64_t)v->tv_nsec;
	    f = (float)TSTONS( v );
	    d = TSTONS( v );

	    /* now convert to strings */
	    timespec_str( v, buf_ts, sizeof(buf_ts) );
	    ns_to_timespec( ts_l32, l32);
	    timespec_str( &ts_l32, buf_l32, sizeof(buf_l32) );
	    ns_to_timespec( ts_l64, l64);
	    timespec_str( &ts_l64, buf_l64, sizeof(buf_l64) );
	    d_str( f, buf_f, sizeof(buf_f) );
	    d_str( d, buf_d, sizeof(buf_d) );

	    /* test strings */
	    if ( strcmp( buf_ts, p->expected) ) {
		fail_ts = "FAIL";
            }
	    if ( strcmp( buf_l32, p->expected) ) {
		fail_l32 = "FAIL";
            }
	    if ( strcmp( buf_l64, p->expected) ) {
		fail_l64 = "FAIL";
            }
	    if ( strcmp( buf_f, p->expected) ) {
		fail_f = "FAIL";
            }
	    if ( strcmp( buf_d, p->expected) ) {
		fail_d = "FAIL";
            }
	    printf( "ts:  %21s %s\n"
	            "l32: %21lld %s\n"
                    "l64: %21lld %s\n"
                    "f:   %21.9f %s\n"
		    "d:   %21.9f %s\n\n",
			buf_ts, fail_ts,
			(long long)l32, fail_l32,
			(long long)l64, fail_l64,
			f, fail_f,
			d, fail_d);

	    if ( p->last ) {
		    break;
	    }
	    p++;
	}

	printf( "\n\nSubtraction examples:\n");

        ex_subtract_float();
}

int main(int argc, char *argv[])
{
    int fail_count = 0;
    int verbose = 0;
    int option;

    while ((option = getopt(argc, argv, "h?vV")) != -1) {
	switch (option) {
	default:
		fail_count = 1;
		/* FALL THROUGH! */
	case '?':
	case 'h':
	    (void)fputs("usage: test_timespec [-v] [-V]\n", stderr);
	    exit(fail_count);
	case 'V':
	    (void)fprintf( stderr, "test_timespec %s\n",
		VERSION);
	    exit(EXIT_SUCCESS);
	case 'v':
	    verbose = 1;
	    break;
	}
    }


    fail_count = test_format( verbose );
    fail_count += test_ts_subtract( verbose );
    fail_count += test_ns_subtract( verbose );

    if ( fail_count ) {
	printf("timespec tests failed %d tests\n", fail_count );
	exit(1);
    }
    printf("timespec tests succeeded\n");

    if ( verbose ) {
	ex_precision();
    }
    exit(0);
}