/* Copyright 2020 Christopher Courtney, aka Drashna Jael're  (@drashna) <drashna@live.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

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

#include "matrix.h"
#include QMK_KEYBOARD_H

#define ROWS_PER_HAND (MATRIX_ROWS / 2)

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

#ifdef BACKLIGHT_ENABLE
#    include "backlight.h"
#endif

#ifdef ENCODER_ENABLE
#    include "encoder.h"
static pin_t encoders_pad[] = ENCODERS_PAD_A;
#    define NUMBER_OF_ENCODERS (sizeof(encoders_pad) / sizeof(pin_t))
#endif

#ifdef POINTING_DEVICE_ENABLE
static uint16_t device_cpi    = 0;
static int8_t   split_mouse_x = 0, split_mouse_y = 0;
#endif

#if defined(USE_I2C)

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

typedef struct _I2C_slave_buffer_t {
    matrix_row_t smatrix[ROWS_PER_HAND];
    uint8_t      backlight_level;
#    if defined(RGBLIGHT_ENABLE) && defined(RGBLIGHT_SPLIT)
    rgblight_syncinfo_t rgblight_sync;
#    endif
#    ifdef ENCODER_ENABLE
    uint8_t encoder_state[NUMBER_OF_ENCODERS];
#    endif
#    ifdef WPM_ENABLE
    uint8_t current_wpm;
#    endif
    int8_t   mouse_x;
    int8_t   mouse_y;
    uint16_t device_cpi;
} I2C_slave_buffer_t;

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

#    define I2C_BACKLIGHT_START offsetof(I2C_slave_buffer_t, backlight_level)
#    define I2C_RGB_START offsetof(I2C_slave_buffer_t, rgblight_sync)
#    define I2C_KEYMAP_START offsetof(I2C_slave_buffer_t, mmatrix)
#    define I2C_ENCODER_START offsetof(I2C_slave_buffer_t, encoder_state)
#    define I2C_WPM_START offsetof(I2C_slave_buffer_t, current_wpm)
#    define I2C_MOUSE_X_START offsetof(I2C_slave_buffer_t, mouse_x)
#    define I2C_MOUSE_Y_START offsetof(I2C_slave_buffer_t, mouse_y)
#    define I2C_MOUSE_DPI_START offsetof(I2C_slave_buffer_t, device_cpi)
#    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
    uint8_t level = is_backlight_enabled() ? get_backlight_level() : 0;
    if (level != i2c_buffer->backlight_level) {
        if (i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_BACKLIGHT_START, (void *)&level, sizeof(level), TIMEOUT) >= 0) {
            i2c_buffer->backlight_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

#    ifdef ENCODER_ENABLE
    i2c_readReg(SLAVE_I2C_ADDRESS, I2C_ENCODER_START, (void *)i2c_buffer->encoder_state, sizeof(i2c_buffer->encoder_state), TIMEOUT);
    encoder_update_raw(i2c_buffer->encoder_state);
#    endif

#    ifdef WPM_ENABLE
    uint8_t current_wpm = get_current_wpm();
    if (current_wpm != i2c_buffer->current_wpm) {
        if (i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_WPM_START, (void *)&current_wpm, sizeof(current_wpm), TIMEOUT) >= 0) {
            i2c_buffer->current_wpm = current_wpm;
        }
    }
#    endif

#    ifdef POINTING_DEVICE_ENABLE
    if (is_keyboard_left()) {
        report_mouse_t temp_report = pointing_device_get_report();
        i2c_readReg(SLAVE_I2C_ADDRESS, I2C_MOUSE_X_START, (void *)&i2c_buffer->mouse_x, sizeof(i2c_buffer->mouse_x), TIMEOUT);
        temp_report.x = i2c_buffer->mouse_x;
        i2c_readReg(SLAVE_I2C_ADDRESS, I2C_MOUSE_Y_START, (void *)&i2c_buffer->mouse_y, sizeof(i2c_buffer->mouse_y), TIMEOUT);
        temp_report.y = i2c_buffer->mouse_y;
        pointing_device_set_report(temp_report);

        if (device_cpi != i2c_buffer->device_cpi) {
            if(i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_MOUSE_DPI_START, (void *)&device_cpi, sizeof(device_cpi), TIMEOUT) >= 0) {
                i2c_buffer->device_cpi = device_cpi
            }
        }
    }
#    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->backlight_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

#    ifdef ENCODER_ENABLE
    encoder_state_raw(i2c_buffer->encoder_state);
#    endif

#    ifdef WPM_ENABLE
    set_current_wpm(i2c_buffer->current_wpm);
#    endif

#    ifdef POINTING_DEVICE_ENABLE
    if (!is_keyboard_left()) {
        static uint16_t cpi;
        if (cpi != i2c_buffer->device_cpi) {
            cpi = i2c_buffer->device_cpi;
            pmw_set_cpi(cpi);
        }
        i2c_buffer->mouse_x = split_mouse_x;
        i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_MOUSE_X_START, (void *)&i2c_buffer->mouse_x, sizeof(i2c_buffer->mouse_x), TIMEOUT);
        i2c_buffer->mouse_y = split_mouse_y;
        i2c_writeReg(SLAVE_I2C_ADDRESS, I2C_MOUSE_Y_START, (void *)&i2c_buffer->mouse_y, sizeof(i2c_buffer->mouse_y), TIMEOUT);
    }

#    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];
#    ifdef ENCODER_ENABLE
    uint8_t encoder_state[NUMBER_OF_ENCODERS];
#    endif
    int8_t mouse_x;
    int8_t mouse_y;
} Serial_s2m_buffer_t;

typedef struct _Serial_m2s_buffer_t {
#    ifdef BACKLIGHT_ENABLE
    uint8_t backlight_level;
#    endif
#    ifdef WPM_ENABLE
    uint8_t current_wpm;
#    endif
    uint16_t device_cpi;
} 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 = is_backlight_enabled() ? get_backlight_level() : 0;
#    endif

#    ifdef ENCODER_ENABLE
    encoder_update_raw((uint8_t *)serial_s2m_buffer.encoder_state);
#    endif

#    ifdef WPM_ENABLE
    // Write wpm to slave
    serial_m2s_buffer.current_wpm = get_current_wpm();
#    endif

#    ifdef POINTING_DEVICE_ENABLE
    if (is_keyboard_left()) {
        report_mouse_t temp_report = pointing_device_get_report();
        temp_report.x              = serial_s2m_buffer.mouse_x;
        temp_report.y              = serial_s2m_buffer.mouse_y;
        pointing_device_set_report(temp_report);
        serial_m2s_buffer.device_cpi = device_cpi;
    }
#    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

#    ifdef ENCODER_ENABLE
    encoder_state_raw((uint8_t *)serial_s2m_buffer.encoder_state);
#    endif

#    ifdef WPM_ENABLE
    set_current_wpm(serial_m2s_buffer.current_wpm);
#    endif

#    ifdef POINTING_DEVICE_ENABLE
    if (!is_keyboard_left()) {
        static uint16_t cpi;
        if (cpi != serial_m2s_buffer.device_cpi) {
            cpi = serial_m2s_buffer.device_cpi;
            pmw_set_cpi(cpi);
        }
        serial_s2m_buffer.mouse_x = split_mouse_x;
        serial_s2m_buffer.mouse_y = split_mouse_y;
    }

#    endif
}

#endif

#ifdef POINTING_DEVICE_ENABLE
void master_mouse_send(int8_t x, int8_t y) {
    split_mouse_x = x;
    split_mouse_y = y;
}
void trackball_set_cpi(uint16_t cpi) {
    if (!is_keyboard_left()) {
        pmw_set_cpi(cpi);
    } else {
        device_cpi = cpi * 1.5;
    }
}
#endif
