/**
 * @file se050_session_internal.h
 * @brief SE050 Session Internal Definitions
 * 
 * Internal definitions for session implementation.
 * 
 * License: MIT (Clean-room implementation)
 */

#ifndef SE050_SESSION_INTERNAL_H
#define SE050_SESSION_INTERNAL_H

#include "se050_i2c_hal.h"
#include "se050_wireguard.h"
#include <stdint.h>

/* Session states */
typedef enum {
    SESSION_STATE_CREATED = 0,
    SESSION_STATE_OPENED,
    SESSION_STATE_CLOSED,
} session_state_t;

/**
 * @brief SCP03 secure channel context
 */
typedef struct se050_scp03_ctx {
    struct se050_session_ctx *session;  /**< Associated session */
    uint8_t enc_key[16];                /**< Encryption key */
    uint8_t mac_key[16];                /**< MAC key */
    uint8_t dek_key[16];                /**< DEK key */
    uint8_t cmd_icv[8];                 /**< Command ICV */
    uint8_t rsp_icv[8];                 /**< Response ICV */
    uint64_t cmd_counter;               /**< Command counter */
    uint64_t rsp_counter;               /**< Response counter */
    uint8_t initialized;                /**< Initialization flag */
} se050_scp03_ctx_t;

/**
 * @brief RNG context (forward declaration)
 */
typedef struct se050_rng_ctx se050_rng_ctx_t;

/**
 * @brief Session context structure
 */
typedef struct se050_session_ctx se050_session_ctx_t;

struct se050_session_ctx {
    se050_i2c_hal_t *hal;           /**< I2C HAL interface */
    session_state_t state;          /**< Current session state */
    uint32_t session_id;            /**< Unique session identifier */
    se050_scp03_ctx_t *scp03;       /**< SCP03 secure channel context */
    uint8_t session_key[32];        /**< Session encryption key */
    size_t session_key_len;         /**< Session key length */
    se050_rng_ctx_t *rng;           /**< RNG context */
};

#endif /* SE050_SESSION_INTERNAL_H */