#ifndef PCAN_BOOT_H
#define PCAN_BOOT_H

#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

#define PCAN_BOOT_VERSION          1U
#define PCAN_BOOT_BLOCK_SIZE       8U
#define PCAN_BOOT_BLOCK_COUNT      65536UL
#define PCAN_BOOT_SLOT_SIZE        (PCAN_BOOT_BLOCK_COUNT * PCAN_BOOT_BLOCK_SIZE)
#define PCAN_BOOT_SLOT_NONE        0xFFU

#define PCAN_BOOT_MSG_CONTROL      0x9U
#define PCAN_BOOT_MSG_DATA_A       0xAU
#define PCAN_BOOT_MSG_DATA_B       0xBU
#define PCAN_BOOT_MSG_STATUS       0xCU
#define PCAN_BOOT_MSG_DISCOVERY    0xDU

#define PCAN_BOOT_ROUTE_FROM_PM      0U
#define PCAN_BOOT_ROUTE_FROM_DEVICE  1U

typedef enum {
    PCAN_BOOT_CMD_IDENTIFY       = 0x01U,
    PCAN_BOOT_CMD_ENTER_BOOT     = 0x02U,
    PCAN_BOOT_CMD_BEGIN_IMAGE    = 0x03U,
    PCAN_BOOT_CMD_BEGIN_COMPAT   = 0x04U,
    PCAN_BOOT_CMD_ERASE          = 0x05U,
    PCAN_BOOT_CMD_VERIFY         = 0x06U,
    PCAN_BOOT_CMD_COMMIT         = 0x07U,
    PCAN_BOOT_CMD_CONFIRM        = 0x08U,
    PCAN_BOOT_CMD_REBOOT         = 0x09U,
    PCAN_BOOT_CMD_ABORT          = 0x0AU,
    PCAN_BOOT_CMD_QUERY_PROGRESS = 0x0BU
} pcan_boot_command_t;

typedef enum {
    PCAN_BOOT_STATUS_OK              = 0x00U,
    PCAN_BOOT_STATUS_BUSY            = 0x01U,
    PCAN_BOOT_STATUS_INVALID_COMMAND = 0x02U,
    PCAN_BOOT_STATUS_WRONG_DEVICE    = 0x03U,
    PCAN_BOOT_STATUS_WRONG_HARDWARE  = 0x04U,
    PCAN_BOOT_STATUS_INVALID_SIZE    = 0x05U,
    PCAN_BOOT_STATUS_CRC_ERROR       = 0x06U,
    PCAN_BOOT_STATUS_FLASH_ERROR     = 0x07U,
    PCAN_BOOT_STATUS_SEQUENCE_ERROR  = 0x08U,
    PCAN_BOOT_STATUS_SIGNATURE_ERROR = 0x09U,
    PCAN_BOOT_STATUS_SESSION_ERROR   = 0x0AU,
    PCAN_BOOT_STATUS_VOLTAGE_ERROR   = 0x0BU,
    PCAN_BOOT_STATUS_INVALID_STATE   = 0x0CU
} pcan_boot_status_t;

typedef enum {
    PCAN_BOOT_STATE_IDLE = 0,
    PCAN_BOOT_STATE_METADATA,
    PCAN_BOOT_STATE_READY_TO_ERASE,
    PCAN_BOOT_STATE_RECEIVING,
    PCAN_BOOT_STATE_VERIFIED,
    PCAN_BOOT_STATE_FAILED
} pcan_boot_state_t;

typedef struct {
    uint32_t image_size;
    uint32_t image_crc32;
    uint32_t firmware_version;
    uint16_t product_type;
    uint8_t hardware_revision_min;
    uint8_t hardware_revision_max;
} pcan_boot_manifest_t;

typedef struct {
    uint8_t device_type;
    uint8_t device_id;
    uint16_t product_type;
    uint8_t hardware_revision;
    uint32_t firmware_version;
    uint8_t active_slot;
    uint8_t ack_window; /**< 1 — ACK каждого блока, 16 — ACK каждых 16 блоков. */
} pcan_boot_config_t;

typedef struct {
    bool (*send)(void *user, uint32_t can_id, const uint8_t *data, uint8_t dlc);
    bool (*erase_slot)(void *user, uint8_t slot);
    bool (*write_slot)(void *user, uint8_t slot, uint32_t offset,
                       const uint8_t *data, uint8_t length);
    bool (*authorize)(void *user, const pcan_boot_manifest_t *manifest);
    bool (*verify_image)(void *user, uint8_t slot,
                         const pcan_boot_manifest_t *manifest);
    bool (*set_pending_slot)(void *user, uint8_t slot,
                             const pcan_boot_manifest_t *manifest);
    bool (*confirm_running_slot)(void *user);
    void (*reboot)(void *user);
} pcan_boot_port_t;

typedef struct {
    pcan_boot_config_t config;
    pcan_boot_port_t port;
    void *port_user;
    pcan_boot_manifest_t manifest;
    pcan_boot_state_t state;
    uint32_t running_crc32;
    uint32_t bytes_received;
    uint16_t next_block;
    uint8_t session_id;
    uint8_t target_slot;
    uint8_t last_status;
    bool have_image;
    bool have_compat;
} pcan_boot_t;

/** Инициализирует экземпляр. Все обязательные callbacks должны быть заданы. */
bool pcan_boot_init(pcan_boot_t *boot, const pcan_boot_config_t *config,
                    const pcan_boot_port_t *port, void *port_user);

/** Сбрасывает незавершённую сессию, не меняя конфигурацию и callbacks. */
void pcan_boot_abort(pcan_boot_t *boot);

/**
 * Обрабатывает один Extended CAN-кадр.
 * Возвращает true, если кадр принадлежал загрузочному сервису этого прибора.
 */
bool pcan_boot_process(pcan_boot_t *boot, uint32_t can_id,
                       const uint8_t *data, uint8_t dlc);

/** Переносимые операции с 29-битным ProtoCAN ID. */
uint32_t pcan_boot_make_id(uint8_t priority, uint8_t route,
                           uint8_t device_type, uint8_t device_id,
                           uint8_t msg_type, uint16_t msg_body);
uint8_t pcan_boot_id_route(uint32_t can_id);
uint8_t pcan_boot_id_device_type(uint32_t can_id);
uint8_t pcan_boot_id_device_id(uint32_t can_id);
uint8_t pcan_boot_id_msg_type(uint32_t can_id);
uint16_t pcan_boot_id_msg_body(uint32_t can_id);

#ifdef __cplusplus
}
#endif

#endif /* PCAN_BOOT_H */