#include "boards/pico.h"
#include "hardware/spi.h"
#include "pico/stdlib.h"
#include "pico/time.h"

// 16MHz 125Kbps
#define MCP_CFG1 (0x03)
#define MCP_CFG2 (0xF0)
#define MCP_CFG3 (0x86)

typedef struct {
  spi_inst_t *CHANNEL;
  uint8_t CS_PIN;
  // uint8_t TX_PIN;
  // uint8_t RX_PIN;
  // uint8_t SCK_PIN;
  // uint32_t SPI_CLOCK;
} mcp2515_config;

struct can_frame {
  uint32_t can_id; // 32 bit CAN_ID + EFF/RTR/ERR flags
  char can_dlc;    //  frame payload length in byte (0 .. CAN_MAX_DLEN) */
  char data[8];    // msg
};

enum MCP_ERROR {
  ERROR_OK = 0,
  ERROR_FAIL = 1,
  ERROR_ALLTXBUSY = 2,
  ERROR_FAILINIT = 3,
  ERROR_FAILTX = 4,
  ERROR_NOMSG = 5
};

void mcp2515_init(mcp2515_config *config, uint8_t cs_pin, uint8_t tx_pin,
                  uint8_t rx_pin, uint8_t sck_pin, spi_inst_t *spi_inst);
enum MCP_ERROR sendMessage(const struct can_frame *frame);
enum MPC_ERROR readMessage(struct can_frame *frame);