#ifndef SHA256_ARM_H
#define SHA256_ARM_H

#include <stdint.h>

// Ensure the ARM NEON headers are included if available
#if defined(__ARM_NEON) || defined(_MSC_VER) || defined(__GNUC__)
#  include <arm_neon.h>
#endif

// Function prototypes
#ifdef __cplusplus
extern "C" {
#endif


/**
 * @brief Resets the SHA256 state to initial values
 * 
 * @param state Array of 8 uint32_t for maintaining state
 */
void sha256_init_arm(uint32_t state[8]);


/**
 * Processes multiple blocks of data with the SHA-256 algorithm using ARMv8 SHA extensions.
 * The caller is responsible for setting the initial state and padding the final block.
 *
 * @param state The initial hash state (8 uint32_t elements).
 * @param data The input data to hash.
 * @param length The length of the input data in bytes. Must be a multiple of 64.
 */
void sha256_process_arm(uint32_t state[8], const uint8_t data[], uint32_t length);

/**
 * Computes a double SHA-256 hash on given data using ARM architecture optimizations. The function first
 * hashes the input data, then hashes the result again. This method is commonly used in blockchain technologies.
 *
 * @param state Array of 8 uint32_t for the hash state, initialized prior to this call.
 * @param data Pointer to the data to be hashed.
 * @param len Length of the data in bytes.
 */
void sha256_double_arm(const uint8_t *input, size_t length, uint8_t hash[SHA256_BLOCK_SIZE]);


void sha256_arm(const uint8_t *input, size_t length, uint8_t hash[SHA256_BLOCK_SIZE]);


#ifdef __cplusplus
}
#endif

#endif // SHA256_ARM_H