#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <float.h>
#include <math.h>
#include <math.h>
#include <ctype.h>
#if defined(TEST_TARGET_calculate)
#include <varch/command.h>
#include <varch/unitt.h>
#include <varch/calculate.h>
#else  
#include "init.h"
#include "command.h"
#include "unitt.h"
#include "calculate.h"
#include "kern.h"
#endif

/************************************************************************************/
/************************************* Unit Test ************************************/
/************************************************************************************/

// #define EXIT_TEST
extern uint64_t unitt_clock(void);

typedef union {
    uint64_t int_;
    double double_;
} doubel_ut;

extern uint64_t unitt_clock(void);

// #define EXIT_TEST

static char expbuffer[1000];

static double random_double() 
{
    doubel_ut random;

    for (int i = 0; i < 8; i++) 
    {
        random.int_ <<= 8;
        random.int_ |= rand() & 0xFF;
    }

#if 0
    if (isnan(random.double_)) random.double_ = 1.0;
    else if (isinf(random.double_))
    {
        if (random.double_ > 0) random.double_ = 2.0;
        else                    random.double_ = -2.0;
    }
    else if (random.double_ == 0.0) random.double_ = 1.0;
#else  
    uint64_t temp = random.int_;
    random.double_ = (double)temp / 100;
#endif 

    return random.double_;
}

static int double_eq(double a, double b)
{
    double epsilon = 1e-6;
    doubel_ut a1 = {.double_ = a}, b1 = {.double_ = b};

    if (a1.int_ == b1.int_) return 1;
    if (isnan(a) && isnan(b)) return 1;
    if (isinf(a) && isinf(b)) return 1;
    if (fabs(a - b) < epsilon) return 1;

    return 0;
}

static int test_add(void)
{
    for (int i = 0; i < 100; i++)
    {
        double a, b;
        doubel_ut r1 = {.int_ = 0}, r2 = {.int_ = 0};

        a = random_double();
        b = random_double();

        snprintf(expbuffer, sizeof(expbuffer), "%lf + %lf", a, b);

        r1.double_ = calculate(expbuffer);
        r2.double_ = a + b;

        if (!double_eq(r1.double_, r2.double_)) 
        {
            printf("add fail: \r\nexpert: \r\n%llu | %lf \r\nactual: \r\n%llu | %lf \r\n", r2.int_, r2.double_, r1.int_, r1.double_);
            #if defined (EXIT_TEST)
            exit(0);
            #endif 
            return UNITT_E_FAIL;
        }
    }
    
    return UNITT_E_OK;
}

static int test_sub(void)
{
    for (int i = 0; i < 100; i++)
    {
        double a, b;
        doubel_ut r1 = {.int_ = 0}, r2 = {.int_ = 0};

        a = random_double();
        b = random_double();

        snprintf(expbuffer, sizeof(expbuffer), "%lf - %lf", a, b);

        r1.double_ = calculate(expbuffer);
        r2.double_ = a - b;

        if (!double_eq(r1.double_, r2.double_)) 
        {
            printf("sub fail: \r\nexpert: \r\n%llu | %lf \r\nactual: \r\n%llu | %lf \r\n", r2.int_, r2.double_, r1.int_, r1.double_);
            #if defined (EXIT_TEST)
            exit(0);
            #endif 
            return UNITT_E_FAIL;
        }
    }
    
    return UNITT_E_OK;
}

static int test_mul(void)
{
    for (int i = 0; i < 100; i++)
    {
        double a, b;
        doubel_ut r1 = {.int_ = 0}, r2 = {.int_ = 0};

        a = random_double();
        b = random_double();

        snprintf(expbuffer, sizeof(expbuffer), "%lf * %lf", a, b);

        r1.double_ = calculate(expbuffer);
        r2.double_ = a * b;

        if (!double_eq(r1.double_, r2.double_)) 
        {
            printf("mul fail: \r\nexpert: \r\n%llu | %lf \r\nactual: \r\n%llu | %lf \r\n", r2.int_, r2.double_, r1.int_, r1.double_);
            #if defined (EXIT_TEST)
            exit(0);
            #endif 
            return UNITT_E_FAIL;
        }
    }
    
    return UNITT_E_OK;
}

static int test_div(void)
{
    for (int i = 0; i < 100; i++)
    {
        double a, b;
        doubel_ut r1 = {.int_ = 0}, r2 = {.int_ = 0};

        a = random_double();
        b = random_double();

        snprintf(expbuffer, sizeof(expbuffer), "%lf / %lf", a, b);

        r1.double_ = calculate(expbuffer);
        r2.double_ = a / b;

        if (!double_eq(r1.double_, r2.double_)) 
        {
            printf("div fail: \r\nexpert: \r\n%llu | %lf \r\nactual: \r\n%llu | %lf \r\n", r2.int_, r2.double_, r1.int_, r1.double_);
            #if defined (EXIT_TEST)
            exit(0);
            #endif 
            return UNITT_E_FAIL;
        }
    }
    
    return UNITT_E_OK;
}

static void unitt_task(void)
{
    static UNITT_TCASE rand_tests[] = {
        UNITT_TCASE(test_add),
        UNITT_TCASE(test_sub),
        UNITT_TCASE(test_mul),
        UNITT_TCASE(test_div),
    };

    static UNITT suites[] = {
        { "calculate suite", rand_tests, sizeof(rand_tests) / sizeof(rand_tests[0]) , unitt_clock },
    };

    UNITT_EXE(suites);
}

/************************************************************************************/
/************************************* Base Test ************************************/
/************************************************************************************/

static void ls(void)
{
    const char *name = NULL;
    int fargc = 0;
    double value = 0;

    while (name = calculate_ls_const(&value))
    {
        printf("- %s<%lf>\r\n", name, value);
    }

    while (name = calculate_ls_func(&fargc))
    {
        printf("- %s(%d)\r\n", name, fargc);
    }
}

static int command_calculate(const char *expression)
{
    double r = NAN;
    if (!expression) return 0;
    r = calculate(expression);
    if (fabs(floor(r) - r) <= DBL_EPSILON && fabs(r) < 1.0e60) printf("%.0lf\r\n", r);
    else if (fabs(r) < 1.0e-6 || fabs(r) > 1.0e9) printf("%e\r\n", r);
    else 
    {
        char p[64];
        int len = 0;
        len = sprintf(p, "%lf", r);
        while (len > 0 && p[len-1] == '0' && p[len-2] != '.') {p[--len] = 0;}
        printf("%s\r\n", p);
    }
    return 1;
}

static double factorial(double n)
{
    if (n < 1) return 1;
    return n * factorial(n - 1);
}

static void test_base(void)
{
    const char *expression[] = {
        "    ( 99 * 3 ) ",
        "  min  (12, 3)",
        "sin (  11 / 2 *  Pi ) + 100 ",
    };

    for (int i = 0; i < sizeof(expression) / sizeof(expression[0]); i++)
    {
        printf("cal: %s = %lf\r\n", expression[i], calculate(expression[i]));
    }
}

static void test_export(void)
{
    int ret = 0;
    ret = calculate_function("fac", factorial, 1);
    printf("export func '%s' ret<%d>\r\n", "fac", ret);
    ret = calculate_constant("K", 1024);
    printf("export const '%s' ret<%d>\r\n", "K", ret);
    ls();
}

/************************************************************************************/
/*************************************  Command  ************************************/
/************************************************************************************/

static void usage(void)
{
    printf(
"Usage: calculate [opt] [arg] ...\n"
"\n"
"options:\n"
"    -e <execute>        Specifies the function to execute, the default is the <base> test\n"
"                        <base>      Test base function\n"
"                        <ut>        Unit test\n"
"                        <cal>       Calculate string math expression\n"
"                        <export>    Test base export function\n"
"    -h                  Print help\n"
"    -v                  Print version\n"
"    -u [<period>]       Unit test period, unit ms, the default is 1000ms\n"
"    -c <calculate>      Calculation expression\n"
"    -l                  Lists the currently supported calculation functions and constants\n"
"\n"
    );
}

static int test(int argc, char *argv[])
{
    char *execute = NULL;
    int ut_period = 1000;
    char *expression = NULL;

    /* reset getopt */
    command_opt_init();

    while (1)
    {
        int opt = command_getopt(argc, argv, "e:hvu::lc:");
        if (opt == -1) break;

        switch (opt) 
        {
        case 'c' :
            expression = command_optarg;
            break;
        case 'l' :
            ls();
            return 0;
        case 'u' :
            if (command_optarg) ut_period = atoi(command_optarg);
            break;
        case 'e' :
            execute = command_optarg;
            break;
        case 'v' :
            printf("calculate version %d.%d.%d\r\n", CALCULATE_V_MAJOR, CALCULATE_V_MINOR, CALCULATE_V_PATCH);
            return 0;
        case '?':
            printf("Unknown option `%c`\r\n", command_optopt);
            return -1;
        case 'h' : 
        default:
            usage();
            return 0;
        }
    }

    if (execute)
    {
        if (!strcmp(execute, "base"))
        {
            test_base();
        }
        else if (!strcmp(execute, "ut"))
        {
            srand((unsigned int)time(NULL));
            #if defined(TEST_TARGET_calculate)
            while (1)
            {
                unitt_task();
                usleep(1000 * ut_period);
            }
            #else  
            printf("create task %d\r\n", task_create(ut_period, unitt_task));
            #endif
        }
        else if (!strcmp(execute, "cal"))
        {
            if (expression)
            {
                command_calculate(expression);
            }
            else  
            {
                printf("Use the -c option to specify the evaluated expression!\r\n");
            }
        }
        else if (!strcmp(execute, "export"))
        {
            test_export();
        }
    }
    else  
    {
        test_base();
    }
    
    return 0;
}

/************************************************************************************/
/************************************ Test entry ************************************/
/************************************************************************************/

#if defined(TEST_TARGET_calculate)
int main(int argc, char *argv[])
{
    return test(argc, argv);
}
#else 
void test_calculate(void)
{
    command_export("calculate", test);

    // command("calculate");
    // command("calculate -e ut");
    // command("calculate -e cal -c 1+2");
    // command("calculate -e export");
}
init_export_app(test_calculate);
#endif