#ifndef _INCLUDE_FRAME_
#define _INCLUDE_FRAME_

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

//#define COM_FRAME_DEBUG

#define COM_FRAME_MAGIC_NUMBER 0xEB90
#define COM_FRAME_DEFAULT_PAYLOAD_LENGTH 2
#define COM_FRAME_PADDING_DATA 0xAA

#define COM_FRAME_TYPE_COMMAND              0x00C0
#define COM_FRAME_TYPE_SPEECH_INJECTED      0x00D0
#define COM_FRAME_TYPE_SPEECH_TEXT          0x00D0
#define COM_FRAME_TYPE_SPEECH_PCM           0x00D1
#define COM_FRAME_TYPE_AUDIO           0x00D1
#define COM_FRAME_TYPE_REQUEST              0x0090
#define COM_FRAME_TYPE_TELEMETRY_REQUEST    0x00B0
#define COM_FRAME_TYPE_TELEMETRY_ANSWER       0x0070
#define COM_FRAME_TYPE_TELEMETRY_ERROR      0x0071

#define COM_FRAME_ADDRESS_VOIX 0x011A

// added by gejp start 2024.10.03
#define COM_FRAME_TYPE_GRANT_TIME 0x0085
#define COM_FRAME_TYPE_VOICE_ANNOUNCEMENT_AND_ALARM_CODE_REQUEST 0x0083 
#define COM_FRAME_TYPE_VOICE_ANNOUNCEMENT_AND_ALARM_CODE_RESPONSE 0x0083 

#define byteswapl(x) (0xff000000 & x << 24) \
                |(0x00ff0000 & x <<  8) \
                |(0x0000ff00 & x >>  8) \
                |(0x000000ff & x >> 24) 
#define byteswaps(x) (0xff00 & x << 8) \
                |(0x00ff & x >> 8)

#ifdef __cplusplus
extern "C" {
#endif

struct ComFrameHeader {
	uint16_t magic_number;
	uint16_t address;
	uint16_t type;
	uint16_t length;
} __attribute__((packed));

typedef struct _ComFrame {
    struct ComFrameHeader header;
    uint8_t payload[COM_FRAME_DEFAULT_PAYLOAD_LENGTH];
} ComFrame;

#define ComFrame_HEADER(frame) ((struct ComFrameHeader*)(frame))
#define ComFrame_ADDRESS(frame) (ComFrame_HEADER(frame)->address)
#define ComFrame_TYPE(frame) (ComFrame_HEADER(frame)->type)
#define ComFrame_PAYLOAD(frame) (frame->payload)
#define ComFrame_PAYLOAD_LENGTH(frame) (ComFrame_HEADER(frame)->length - 1)
#define ComFrame_PAYLOAD_ALIGNED_LENGTH(frame) (ComFrame_HEADER(frame)->length & (~1))
#define ComFrame_CHECKSUM(frame) (((uint16_t*)&(frame)->payload)[ComFrame_HEADER(frame)->length >> 1])
#define ComFrame_LENGTH(frame) (sizeof(ComFrame) + ComFrame_PAYLOAD_ALIGNED_LENGTH(frame) - COM_FRAME_DEFAULT_PAYLOAD_LENGTH + sizeof(uint16_t))

/// @brief init frame header struct
/// @param header header struct
/// @param address device address
/// @param type frame type
/// @param length frame payload length + 1
static __inline void ComFrameHeader_Init(struct ComFrameHeader* header, uint16_t address, uint16_t type, uint16_t length) {
    header->magic_number = COM_FRAME_MAGIC_NUMBER;
    header->address = address;
    header->type = type;
    header->length = length;
}

/// @brief swap haeder structure endianness
/// @param header header struct
static __inline void ComFrameHeader_SwapEndian(struct ComFrameHeader* header) {
    header->magic_number = byteswaps(header->magic_number);
    header->address = byteswaps(header->address);
    header->type = byteswaps(header->type);
    header->length = byteswaps(header->length);
}

/// @brief check magic number of header struct
/// @param header header struct
/// @param swap_endian whether to switch endianness
/// @return structure validity, true means invalid
static __inline bool ComFrameHeader_Check(const struct ComFrameHeader* header, const bool swap_endian) {
    uint16_t number = header->magic_number;
    if (swap_endian) {
        number = byteswaps(number);
    }
    if (number != COM_FRAME_MAGIC_NUMBER) {
        return true;
    }
    number = header->address;
    if (swap_endian) {
        number = byteswaps(number);
    }
    if (number != COM_FRAME_ADDRESS_VOIX) {
        return true;
    }
    if (ComFrame_LENGTH(header) < 12) {
        return true;
    }
    number = header->type;
    if (swap_endian) {
        number = byteswaps(number);
    }
    // if ( // commented by gejp 20201007
    //     number != COM_FRAME_TYPE_COMMAND &&
    //     number != COM_FRAME_TYPE_SPEECH_INJECTED &&
    //     number != COM_FRAME_TYPE_SPEECH_TEXT &&
    //     number != COM_FRAME_TYPE_SPEECH_PCM &&
    //     number != COM_FRAME_TYPE_AUDIO &&
    //     number != COM_FRAME_TYPE_REQUEST &&
    //     number != COM_FRAME_TYPE_TELEMETRY_REQUEST
    // ) {
    //     return true;
    // }
    return false;
}

/// @brief create new com frame uninitialized
/// @param payload_length length of payload
/// @return new uinitialized frame
static __inline ComFrame* ComFrame_NewUninited(uint16_t payload_length) {
    if (payload_length & 1) {
        payload_length += 1;
    }
    return (ComFrame*)malloc(sizeof(ComFrame) + payload_length - COM_FRAME_DEFAULT_PAYLOAD_LENGTH + sizeof(uint16_t));
}

/// @brief get frame checksum
/// @param frame com frame struct
/// @param swap_endian whether to switch endianness
/// @return checksum
static __inline uint16_t ComFrame_Checksum(const ComFrame* frame, const bool swap_endian) {
    const uint16_t* buffer = (const uint16_t*)&frame->payload;
    uint16_t length = ComFrame_HEADER(frame)->length;
    if (swap_endian) {
        length = byteswaps(length);
    }
    return buffer[length >> 1];
}

/// @brief get frame length
/// @param frame com frame struct
/// @param swap_endian whether to switch endianness
/// @return length of the frame
static __inline uint32_t ComFrame_Length(const ComFrame* frame, const bool swap_endian) {
    uint16_t length = ComFrame_HEADER(frame)->length;
    if (swap_endian) {
        length = byteswaps(length);
    }
    length &= (~1);
    return sizeof(ComFrame) + length - COM_FRAME_DEFAULT_PAYLOAD_LENGTH + sizeof(uint16_t);
}

/// @brief destroy the frame
/// @param frame the frame to destroy
static __inline void ComFrame_Del(ComFrame* frame) {
    if (frame) free(frame);
}

/// @brief flush receive buffer
/// @param offset the size used, usually the length of the data frame
/// @param buffer receive buffer
/// @param p_cached_size cache size to reset, not null
/// @note please set the offset to 0 after calling the function if used with ComFrame_ReceiveEx
static __inline void ComFrame_ReceiveFlushBuffer(size_t offset, uint8_t* buffer, size_t* p_cached_size) {
    *p_cached_size -= offset;
    memmove(buffer, buffer + offset, *p_cached_size);
}

/// @brief calculate the checksum of the specified payload
/// @param header header struct (must be little endian)
/// @param payload payload data
/// @return checksum
uint16_t ComFramePayload_EvalChecksum(const struct ComFrameHeader* header, const void* payload);

/// @brief verify the checksum of the specified payload
/// @param header header struct (must be little endian)
/// @param payload payload data
/// @param checksum checksum to verify
/// @param swap_checksum_endian whether to switch checksum endianness
/// @return payload validity, true means invalid
bool ComFramePayload_VerifyChecksum(const struct ComFrameHeader* header, const void* payload, uint16_t checksum);

/// @brief create new com frame from header and known checksum
/// @param header header struct (must be little endian)
/// @param payload payload data
/// @param checksum payload checksum
/// @param swap_endian whether to switch endianness
/// @return new frame
ComFrame* ComFrame_FromHeaderEx(const struct ComFrameHeader* header, const void* payload, uint16_t checksum, const bool swap_endian);

/// @brief create new com frame from header
/// @param header header struct (must be little endian)
/// @param payload payload data
/// @param swap_endian whether to switch endianness
/// @return new frame
ComFrame* ComFrame_FromHeader(const struct ComFrameHeader* header, const void* payload, const bool swap_endian);

/// @brief create new com frame
/// @param address device address
/// @param type frame type
/// @param payload payload data
/// @param payload_length payload data real length
/// @param swap_endian whether to switch endianness
/// @return new frame
ComFrame* ComFrame_New(uint16_t address, uint16_t type, const void* payload, uint16_t payload_length, const bool swap_endian);

/// @brief update frame payload and checksum
/// @param frame com frame struct
/// @param payload payload data or NULL, if set to NULL, the payload will not be updated.
/// @param payload_length payload data real length
/// @param swap_endian whether to switch endianness
void ComFrame_UpdatePayload(ComFrame* frame, const void* payload, const uint16_t payload_length, const bool swap_endian);

/// @brief verify frame checksum
/// @param frame con frame struct
/// @param swap_endian whether to switch endianness
/// @return structure validity, true means invalid
bool ComFrame_Verify(const ComFrame* frame, const bool swap_endian);

/// @brief send a frame to com
/// @param tty_id com tty id
/// @param frame con frame struct
/// @param swap_endian whether to switch endianness
/// @return error number, 0 means ok
ssize_t ComFrame_Send(int tty_id, const ComFrame* frame, const bool swap_endian);

/// @brief receive a frame from com
/// @param tty_id com tty id
/// @param buffer_size receive buffer size
/// @param swap_endian whether to switch endianness
/// @return new frame (little endian) or NULL
ComFrame* ComFrame_Receive(int tty_id, const size_t buffer_size, const bool swap_endian);

/// @brief receive a frame from com
/// @param tty_id com tty id
/// @param buffer buffer pointer, create a new one when it is NULL
/// @param buffer_size receive buffer size
/// @param p_offset offset will be set if not null
/// @param p_cached_size cached size will be set if not null
/// @param p_run_flag run flag pointer, if the inner date is set to false, the function will stop and return NULL
/// @param swap_endian whether to switch endianness
/// @return frame (little endian) in buffer or NULL
ComFrame* ComFrame_ReceiveEx(int tty_id, void* buffer, const size_t buffer_size, size_t* p_offset, size_t* p_cached_size, bool* p_run_flag, const bool swap_endian);

int get_com_tty_id(const char* path, unsigned int baudRate);
void init_tty(int tty_id, unsigned int baudRate);

#ifdef __cplusplus
}
#endif

#endif