/*
  Copyright 2018, UCAR/Unidata
  See COPYRIGHT file for copying and redistribution conditions.
*/

#include "config.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

#include "netcdf.h"
#include "netcdf_filter.h"

#undef DEBUG

#define PARAMS_ID 32768

/* The C standard apparently defines all floating point constants as double;
   we rely on that in this code. Update: apparently not true when
   -ansi flag is used.
*/
#define DBLVAL 12345678.12345678

#define FLTVAL 789.0

#define LONGLONGVAL -9223372036854775807LL
#define ULONGLONGVAL 18446744073709551615ULL

#define MAXPARAMS 32
#define NPARAMS 16 /* # of unsigned ints in params */

/* Test support for the conversions */
/* Not sure if this kind of casting via union is legal C99 */
static union {
    unsigned int ui;
    float f;
} uf;

static union {
    unsigned int ui[2];
    double d;
} ud;

static union {
    unsigned int ui[2];
    unsigned long long ull;
    long long ll;
} ul;

/* Expected contents of baseline:
id = 32768
index	spec item	Value
----------------------------------------
0	-17b			4294967279
1	23ub			23
2	-25S			42949677271
3	27US			27
4	77			77
5	93U			93
6	2147483647		?
7	-2147483648		?
8	4294967295U		?
9	789f			1145389056
<8-bytes start here >
10	-9223372036854775807L	1, 2147483647
12	18446744073709551615UL	4294967295U, 4294967295U
14	12345678.12345678d	3287505826, 1097305129

expected (LE):
{239, 23, 65511, 27, 77, 93, 2147483647, 2147483648, 4294967295, 1145389056,
 1, 2147483648, 4294967295, 4294967295, 3287505826, 1097305129}

params (LE):
0x000000ef
0x00000017
0x0000ffe7
0x0000001b
0x0000004d
0x0000005d
0x7fffffff
0x80000000
0xffffffff
0x44454000
0x000000001 .ll
0x80000000
0xffffffff .ull
0xffffffff
0xc3f35ba2 .d
0x41678c29

expected (BE):
{239, 23, 65511, 27, 77, 93, 2147483647, 2147483648, 4294967295, 1145389056,
 16777216, 128, 4294967295, 4294967295, 2723935171, 697067329}

params (BE):
0x000000ef
0x00000017
0x0000ffe7
0x0000001b
0x0000004d
0x0000005d
0x7fffffff
0x80000000
0xffffffff
0x44454000
0x01000000 .ll
0x00000080
0xffffffff .ull
0xffffffff
0xa25bf3c3 .d
0x298c6741

*/

static unsigned int baseline[MAXPARAMS]; /* Expected */

static const char* spec = 
"user-defined, -17b, 23ub, -25S, 27US, 77, 93U, 2147483647, -2147483648, 4294967295U, 789f, -9223372036854775807L, 18446744073709551615UL, 12345678.12345678d";

/* Define the type strings for each spec entry */
static const char* spectype[] = {"i", "b", "ub", "s", "us", "i", "ui", "i", "i", "ui", "f", "ll", "ull", "d"};

static int nerrs = 0;

static void
mismatch(size_t i, unsigned int *params, const char* tag)
{
    fprintf(stderr,"mismatch: %s [%d] baseline=%u params=%u\n",tag,(int)i,baseline[i],params[i]);
    fflush(stderr);
    nerrs++;
}

static void
mismatch2(size_t i, unsigned int *params, const char* tag)
{
    fprintf(stderr,"mismatch2: %s [%ld-%ld] baseline=%u,%u params=%u,%u\n",
	tag,(long)i,(long)(i+1),baseline[i],baseline[i+1],params[i],params[i+1]);
    fflush(stderr);
    nerrs++;
}

static void
insert(int index, void* src, size_t size)
{
    void* dst = &baseline[index];
    memcpy(dst,src,size);
}

static void
buildbaseline(void)
{
    unsigned int val4;
    unsigned long long val8;
    float float4;
    double float8;

    val4 = ((unsigned int)-17) & 0xff;
    insert(0,&val4,sizeof(val4)); /* signed int*/
    val4 = (unsigned int)23;
    insert(1,&val4,sizeof(val4)); /* unsigned int*/
    val4 = ((unsigned int)-25) & 0xffff;
    insert(2,&val4,sizeof(val4)); /* signed int*/
    val4 = (unsigned int)27;
    insert(3,&val4,sizeof(val4)); /* unsigned int*/
    val4 = (unsigned int)77;
    insert(4,&val4,sizeof(val4)); /* signed int*/
    val4 = (unsigned int)93;
    insert(5,&val4,sizeof(val4)); /* unsigned int*/
    val4 = 2147483647; /*0x7fffffff*/
    insert(6,&val4,sizeof(val4)); /* signed int */
    val4 = (-2147483647)-1; /*0x80000000*/
    insert(7,&val4,sizeof(val4)); /* signed int */
    val4 = 4294967295U; /*0xffffffff*/
    insert(8,&val4,sizeof(val4)); /* unsigned int */
    float4 = (float)FLTVAL;
    insert(9,&float4,sizeof(float4)); /*float */
    val8 = LONGLONGVAL;
    insert(10,&val8,sizeof(val8)); /* signed long long */
    val8 = ULONGLONGVAL;
    insert(12,&val8,sizeof(val8)); /* unsigned long long */
    float8 = DBLVAL;
    insert(14,&float8,sizeof(float8)); /* double */
}

/**************************************************/
int
main(int argc, char **argv)
{
    int stat = 0;
    size_t i;
    /* Provide for 8-byte values */
    long long basell;
    unsigned long long baseull;
    float basef;
    double based;
    NC4_Filterspec* pfs = NULL;

    printf("\nTesting filter parser.\n");

    buildbaseline(); /* Build our comparison vector */

    stat = NC_parsefilterspec(spec,NC_FILTER_FORMAT_HDF5,(NC_Filterspec**)&pfs);
    if(stat) {
	fprintf(stderr,"NC_parsefilterspec failed\n");
	exit(1);
    }
    
    if(pfs->filterid != PARAMS_ID)
        fprintf(stderr,"mismatch: id: expected=%u actual=%u\n",(unsigned int)PARAMS_ID,pfs->filterid);

    /* Do all the 32 bit tests */
    for(i=0;i<=8;i++) {
	if(baseline[i] != pfs->params[i])
	    mismatch(i,pfs->params,spectype[i]);
    }

    /* float */
    uf.ui = pfs->params[9];
    memcpy(&basef,&baseline[9],4);
    if(uf.f != basef)
	mismatch(9,pfs->params,"uf.f");

    /* signed long long */
    ul.ui[0] = pfs->params[10];
    ul.ui[1] = pfs->params[11];
    NC4_filterfix8((unsigned char*)&ul.ll,1);
    memcpy(&basell,&baseline[10],8);
    if(ul.ll != basell)
	mismatch2(10,pfs->params,"ul.ll");

    /* unsigned long long */
    ul.ui[0] = pfs->params[12];
    ul.ui[1] = pfs->params[13];
    NC4_filterfix8((unsigned char*)&ul.ull,1);
    memcpy(&baseull,&baseline[12],8);
    if(ul.ull != baseull)
	mismatch2(12,pfs->params,"ul.ull");

    /* double */
    ud.ui[0] = pfs->params[14];
    ud.ui[1] = pfs->params[15];
    NC4_filterfix8((unsigned char*)&ud.d,1);
    memcpy(&based,&baseline[14],8);
    if(ud.d != based)
	mismatch2(14,pfs->params,"ud.d");

    if (!nerrs)
       printf("SUCCESS!!\n");

    if(pfs && pfs->params) free(pfs->params);
    if(pfs) free(pfs);
    
    return (nerrs > 0 ? 1 : 0);
}

#ifdef DEBUG

/* Look at q0 and q1) to determine type */
static int
gettype(const int q0, const int q1, int* isunsignedp)
{
    int type = 0;
    int isunsigned = 0;
    char typechar;
    
    isunsigned = (q0 == 'u' || q0 == 'U');
    if(q1 == '\0')
	typechar = q0; /* we were given only a single char */
    else if(isunsigned)
	typechar = q1; /* we have something like Ux as the tag */
    else
	typechar = q1; /* look at last char for tag */
    switch (typechar) {
    case 'f': case 'F': case '.': type = 'f'; break; /* float */
    case 'd': case 'D': type = 'd'; break; /* double */
    case 'b': case 'B': type = 'b'; break; /* byte */
    case 's': case 'S': type = 's'; break; /* short */
    case 'l': case 'L': type = 'l'; break; /* long long */
    case '0': case '1': case '2': case '3': case '4':
    case '5': case '6': case '7': case '8': case '9': type = 'i'; break;
    case 'u': case 'U': type = 'i'; isunsigned = 1; break; /* unsigned int */
    case '\0': type = 'i'; break;
    default: break;
    }
    if(isunsignedp) *isunsignedp = isunsigned;
    return type;
}

#ifdef WORDS_BIGENDIAN
/* Byte swap an 8-byte integer in place */
static void
byteswap8(unsigned char* mem)
{
    unsigned char c;
    c = mem[0];
    mem[0] = mem[7];
    mem[7] = c;
    c = mem[1];
    mem[1] = mem[6];
    mem[6] = c;
    c = mem[2];
    mem[2] = mem[5];
    mem[5] = c;
    c = mem[3];
    mem[3] = mem[4];
    mem[4] = c;
}

/* Byte swap an 8-byte integer in place */
static void
byteswap4(unsigned char* mem)
{
    unsigned char c;
    c = mem[0];
    mem[0] = mem[3];
    mem[3] = c;
    c = mem[1];
    mem[1] = mem[2];
    mem[2] = c;
}

#endif

#if 0
static void
NC4_filterfix8(unsigned char* mem, int decode)
{
#ifdef WORDS_BIGENDIAN
    if(decode) { /* Apply inverse of the encode case */
	byteswap4(mem); /* step 1: byte-swap each piece */
	byteswap4(mem+4);
	byteswap8(mem); /* step 2: convert to little endian format */
    } else { /* encode */
	byteswap8(mem); /* step 1: convert to little endian format */
	byteswap4(mem); /* step 2: byte-swap each piece */
	byteswap4(mem+4);
    }
#else /* Little endian */
    /* No action is necessary */
#endif	    
}
#endif

#endif /*DEBUG*/