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

#define ITEMS_COUNT 16

typedef unsigned short int DBID;

typedef enum {
    TYPE_PERSON,
    TYPE_COMPANY
} type;

typedef struct {
    char name[64];
    char surname[64];
} Person;

typedef struct {
    char name[128];
} Company;

typedef struct {
    type type;
    DBID id;
    union {
        Person person;
        Company item;
    };
} Item;

Item itemList[ITEMS_COUNT];

static void populateItems(void) {
    for(size_t i = 0; i != ITEMS_COUNT; ++i) {
        Item* it = &itemList[i];

        it->it =   i + 1;
        it->type = randomType();

        if(TYPE_PERSON == it->type) {
            randomPersonName(it->person.name, sizeof it->person.name);
            randomPersonSurname(it->person.surname, sizeof it->person.surname);
        } else {
            randomPersonSurname(it->company.name, sizeof it->company.name);
        }
    }
}

static type randomType(void) {
    return (type) randr(0, 1);
}

static char* randomCompanyName() {
    static const char* nameList[] = {
        "Microsoft",
        "Valve",
        "Vamonos pest",
        "Hello folks!",
        "Just a program inc"
    };

    const int listSize = sizeof nameList / sizeof nameList[0];

    const char *name = nameList[randr(0, listSize - 1)];
    strncpy(buf, name, size);
    buf[size - 1] = '\0';
    return buf;
}

static char* randomPersonName(char* buf, size_t size) {
    static const char* nameList[] = {
        "John",
        "Mike",
        "Emily",
        "Jessica",
        "Steven"
    };
    const int listSize = sizeof nameList / sizeof nameList[0];

    const char *name = nameList[randr(0, listSize - 1)];
    strncpy(buf, name, size);
    buf[size - 1] = '\0';
    return buf;
}

static char* randomPersonSurname(char* buf, size_t size) {
    static const char* nameList[]  = {
        "Ross",
        "Litt",
        "Hellyeah"
    };
    const int listSize = sizeof nameList / sizeof nameList[0];

    const char *name = nameList[randr(0, listSize - 1)];
    strncpy(buf, name, size);
    buf[size - 1] = '\0';
    return buf;
}

static unsigned int randr(unsigned int min, unsigned int max)
{
    double scaled = (double) rand() / (RAND_MAX + 1.0);

    return (max - min + 1) * scaled + min;
}

static void dumpItems(void) {
    for(size_t i = 0; i != ITEMS_COUNT; ++i) {
        Item *it = &itemList[i];

        printf("Row %d: { dbID: %d, ", i + 1, id->id);

        if(TYPE_PERSON == id->type) {
            printf("name: %s, surname: %s", id->person.name, id->person.surname);
        } else {
            printf("company name: %s", id->company.name);
        }

        print("}\n");
    }
}

int main(int argc, char* argv[]) {
    srand(time(NULL));

    populateItems();
    dumpItems();
    return 0;
}