#include <string.h>
#include <stddef.h>

#include "config.h"
#include "matrix.h"
#include "quantum.h"

#define ROWS_PER_HAND (MATRIX_ROWS / 2)

#ifdef RGBLIGHT_ENABLE
#  include "rgblight.h"
#endif

#ifdef BACKLIGHT_ENABLE
#  include "backlight.h"
extern backlight_config_t backlight_config;
#endif

#if defined(USE_I2C) || defined(EH)

#  include "i2c_master.h"
#  include "i2c_slave.h"

typedef struct _I2C_slave_buffer_t {
    uint8_t      backlit_level;
#if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
    rgblight_syncinfo_t rgblight_sync;
#endif
    matrix_row_t smatrix[ROWS_PER_HAND];
} I2C_slave_buffer_t;

static I2C_slave_buffer_t * const i2c_buffer = (I2C_slave_buffer_t *)i2c_slave_reg;

#  define I2C_BACKLIT_START offsetof(I2C_slave_buffer_t, backlit_level)
#  define I2C_RGB_START offsetof(I2C_slave_buffer_t, rgblight_sync)
#  define I2C_KEYMAP_START offsetof(I2C_slave_buffer_t, smatrix)

#  define TIMEOUT 100

#  ifndef SLAVE_I2C_ADDRESS
#    define SLAVE_I2C_ADDRESS 0x32
#  endif

// Get rows from other half over i2c
bool transport_master(matrix_row_t matrix[]) {
  i2c_readReg(SLAVE_I2C_ADDRESS, I2C_KEYMAP_START, (void *)matrix, sizeof(i2c_buffer->smatrix), TIMEOUT);

  // write backlight info
#  ifdef BACKLIGHT_ENABLE
  static uint8_t prev_level = ~0;
  uint8_t        level      = get_backlight_level();
  if (level != prev_level) {
    if (i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_BACKLIT_START, (void *)&level, sizeof(level), TIMEOUT) >= 0) {
      prev_level = level;
    }
  }
#  endif

#  if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
  if (rgblight_get_change_flags()) {
    rgblight_syncinfo_t rgblight_sync;
    rgblight_get_syncinfo(&rgblight_sync);
    if (i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_RGB_START,
                     (void *)&rgblight_sync, sizeof(rgblight_sync), TIMEOUT) >= 0) {
      rgblight_clear_change_flags();
    }
  }
#  endif

  return true;
}

void transport_slave(matrix_row_t matrix[]) {
  // Copy matrix to I2C buffer
  memcpy((void*)i2c_buffer->smatrix, (void *)matrix, sizeof(i2c_buffer->smatrix));

// Read Backlight Info
#  ifdef BACKLIGHT_ENABLE
  backlight_set(i2c_buffer->backlit_level);
#  endif

#  if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
  // Update the RGB with the new data
  if (i2c_buffer->rgblight_sync.status.change_flags != 0) {
      rgblight_update_sync(&i2c_buffer->rgblight_sync, false);
      i2c_buffer->rgblight_sync.status.change_flags = 0;
  }
#  endif
}

void transport_master_init(void) { i2c_init(); }

void transport_slave_init(void) { i2c_slave_init(SLAVE_I2C_ADDRESS); }

#else  // USE_SERIAL

#  include "serial.h"

typedef struct _Serial_s2m_buffer_t {
  // TODO: if MATRIX_COLS > 8 change to uint8_t packed_matrix[] for pack/unpack
  matrix_row_t smatrix[ROWS_PER_HAND];
} Serial_s2m_buffer_t;

typedef struct _Serial_m2s_buffer_t {
#  ifdef BACKLIGHT_ENABLE
  uint8_t           backlight_level;
#  endif
} Serial_m2s_buffer_t;

#if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
// When MCUs on both sides drive their respective RGB LED chains,
// it is necessary to synchronize, so it is necessary to communicate RGB
// information. In that case, define RGBLIGHT_SPLIT with info on the number
// of LEDs on each half.
//
// Otherwise, if the master side MCU drives both sides RGB LED chains,
// there is no need to communicate.

typedef struct _Serial_rgblight_t {
    rgblight_syncinfo_t rgblight_sync;
} Serial_rgblight_t;

volatile Serial_rgblight_t serial_rgblight = {};
uint8_t volatile status_rgblight           = 0;
#endif

volatile Serial_s2m_buffer_t serial_s2m_buffer = {};
volatile Serial_m2s_buffer_t serial_m2s_buffer = {};
uint8_t volatile status0                       = 0;

enum serial_transaction_id {
    GET_SLAVE_MATRIX = 0,
#if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
    PUT_RGBLIGHT,
#endif
};

SSTD_t transactions[] = {
    [GET_SLAVE_MATRIX] = {
        (uint8_t *)&status0,
        sizeof(serial_m2s_buffer),
        (uint8_t *)&serial_m2s_buffer,
        sizeof(serial_s2m_buffer),
        (uint8_t *)&serial_s2m_buffer,
    },
#if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
    [PUT_RGBLIGHT] = {
        (uint8_t *)&status_rgblight,
        sizeof(serial_rgblight),
        (uint8_t *)&serial_rgblight,
        0, NULL // no slave to master transfer
    },
#endif
};

void transport_master_init(void) { soft_serial_initiator_init(transactions, TID_LIMIT(transactions)); }

void transport_slave_init(void) { soft_serial_target_init(transactions, TID_LIMIT(transactions)); }

#if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)

// rgblight synchronization information communication.

void transport_rgblight_master(void) {
  if (rgblight_get_change_flags()) {
    rgblight_get_syncinfo((rgblight_syncinfo_t *)&serial_rgblight.rgblight_sync);
    if (soft_serial_transaction(PUT_RGBLIGHT) == TRANSACTION_END) {
        rgblight_clear_change_flags();
    }
  }
}

void transport_rgblight_slave(void) {
  if (status_rgblight == TRANSACTION_ACCEPTED) {
    rgblight_update_sync((rgblight_syncinfo_t *)&serial_rgblight.rgblight_sync,
                         false);
    status_rgblight = TRANSACTION_END;
  }
}

#else
#define transport_rgblight_master()
#define transport_rgblight_slave()
#endif

bool transport_master(matrix_row_t matrix[]) {
#ifndef SERIAL_USE_MULTI_TRANSACTION
  if (soft_serial_transaction() != TRANSACTION_END) {
    return false;
  }
#else
  transport_rgblight_master();
  if (soft_serial_transaction(GET_SLAVE_MATRIX) != TRANSACTION_END) {
    return false;
  }
#endif

  // TODO:  if MATRIX_COLS > 8 change to unpack()
  for (int i = 0; i < ROWS_PER_HAND; ++i) {
    matrix[i] = serial_s2m_buffer.smatrix[i];
  }

#  ifdef BACKLIGHT_ENABLE
  // Write backlight level for slave to read
  serial_m2s_buffer.backlight_level = backlight_config.enable ? backlight_config.level : 0;
#  endif

  return true;
}

void transport_slave(matrix_row_t matrix[]) {
  transport_rgblight_slave();
  // TODO: if MATRIX_COLS > 8 change to pack()
  for (int i = 0; i < ROWS_PER_HAND; ++i) {
    serial_s2m_buffer.smatrix[i] = matrix[i];
  }
#  ifdef BACKLIGHT_ENABLE
  backlight_set(serial_m2s_buffer.backlight_level);
#  endif
}

#endif