#include "furi-hal-random.h"
#include <furi.h>
#include <furi-hal.h>

#include <stm32wbxx_ll_rng.h>
#include <stm32wbxx_ll_hsem.h>

#include <hw_conf.h>

uint32_t furi_hal_random_get() {

    while( LL_HSEM_1StepLock(HSEM, CFG_HW_RNG_SEMID));
    LL_RNG_Enable(RNG);

    while (!LL_RNG_IsActiveFlag_DRDY(RNG));

    if ((LL_RNG_IsActiveFlag_CECS(RNG)) || (LL_RNG_IsActiveFlag_SECS(RNG))) {
        furi_crash("TRNG error");
    }

    uint32_t random_val = LL_RNG_ReadRandData32(RNG);

    LL_RNG_Disable(RNG);
    LL_HSEM_ReleaseLock(HSEM, CFG_HW_RNG_SEMID, 0);

    return random_val;
}

void furi_hal_random_fill_buf(uint8_t* buf, uint32_t len) {

    while( LL_HSEM_1StepLock(HSEM, CFG_HW_RNG_SEMID));
    LL_RNG_Enable(RNG);

    for (uint32_t i = 0; i < len; i+= 4) {
        while (!LL_RNG_IsActiveFlag_DRDY(RNG));

        if ((LL_RNG_IsActiveFlag_CECS(RNG)) || (LL_RNG_IsActiveFlag_SECS(RNG))) {
            furi_crash("TRNG error");
        }

        uint32_t random_val = LL_RNG_ReadRandData32(RNG);

        uint8_t len_cur = ((i+4) < len) ? (4) : (len-i);
        memcpy(&buf[i], &random_val, len_cur);
    }

    LL_RNG_Disable(RNG);
    LL_HSEM_ReleaseLock(HSEM, CFG_HW_RNG_SEMID, 0);
}

void srand(unsigned seed) {
}

int rand() {
    return (furi_hal_random_get() & RAND_MAX);
}