/*
* Copyright © 2020 Wolfgang Christl

* Permission is hereby granted, free of charge, to any person obtaining a copy of this 
* software and associated documentation files (the “Software”), to deal in the Software 
* without restriction, including without limitation the rights to use, copy, modify, merge, 
* publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons 
* to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or 
* substantial portions of the Software.
* 
* THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, 
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR 
* PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE 
* FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 
* SOFTWARE.
*/

#include <esp_log.h>
#include <driver/i2c.h>
#ifdef LV_LVGL_H_INCLUDE_SIMPLE
#include <lvgl.h>
#else
#include <lvgl/lvgl.h>
#endif
#include "ft6x36.h"
#include "tp_i2c.h"
#include "../lvgl_i2c_conf.h"

#define TAG "FT6X36"


ft6x36_status_t ft6x36_status;
uint8_t current_dev_addr;       // set during init

esp_err_t ft6x06_i2c_read8(uint8_t slave_addr, uint8_t register_addr, uint8_t *data_buf) {
    i2c_cmd_handle_t i2c_cmd = i2c_cmd_link_create();

    i2c_master_start(i2c_cmd);
    i2c_master_write_byte(i2c_cmd, (slave_addr << 1) | I2C_MASTER_WRITE, true);
    i2c_master_write_byte(i2c_cmd, register_addr, I2C_MASTER_ACK);

    i2c_master_start(i2c_cmd);
    i2c_master_write_byte(i2c_cmd, (slave_addr << 1) | I2C_MASTER_READ, true);

    i2c_master_read_byte(i2c_cmd, data_buf, I2C_MASTER_NACK);
    i2c_master_stop(i2c_cmd);
    esp_err_t ret = i2c_master_cmd_begin(TOUCH_I2C_PORT, i2c_cmd, 1000 / portTICK_RATE_MS);
    i2c_cmd_link_delete(i2c_cmd);
    return ret;
}

/**
  * @brief  Read the FT6x36 gesture ID. Initialize first!
  * @param  dev_addr: I2C FT6x36 Slave address.
  * @retval The gesture ID or 0x00 in case of failure
  */
uint8_t ft6x36_get_gesture_id() {
    if (!ft6x36_status.inited) {
        ESP_LOGE(TAG, "Init first!");
        return 0x00;
    }
    uint8_t data_buf;
    esp_err_t ret;
    if ((ret = ft6x06_i2c_read8(current_dev_addr, FT6X36_GEST_ID_REG, &data_buf) != ESP_OK))
        ESP_LOGE(TAG, "Error reading from device: %s", esp_err_to_name(ret));
    return data_buf;
}

/**
  * @brief  Initialize for FT6x36 communication via I2C
  * @param  dev_addr: Device address on communication Bus (I2C slave address of FT6X36).
  * @retval None
  */
void ft6x06_init(uint16_t dev_addr) {
    if (!ft6x36_status.inited) {

/* I2C master is initialized before calling this function */
#if 0
        esp_err_t code = i2c_master_init();
#else
        esp_err_t code = ESP_OK;
#endif

        if (code != ESP_OK) {
            ft6x36_status.inited = false;
            ESP_LOGE(TAG, "Error during I2C init %s", esp_err_to_name(code));
        } else {
            ft6x36_status.inited = true;
            current_dev_addr = dev_addr;
            uint8_t data_buf;
            esp_err_t ret;
            ESP_LOGI(TAG, "Found touch panel controller");
            if ((ret = ft6x06_i2c_read8(dev_addr, FT6X36_PANEL_ID_REG, &data_buf) != ESP_OK))
                ESP_LOGE(TAG, "Error reading from device: %s",
                         esp_err_to_name(ret));    // Only show error the first time
            ESP_LOGI(TAG, "\tDevice ID: 0x%02x", data_buf);

            ft6x06_i2c_read8(dev_addr, FT6X36_CHIPSELECT_REG, &data_buf);
            ESP_LOGI(TAG, "\tChip ID: 0x%02x", data_buf);

            ft6x06_i2c_read8(dev_addr, FT6X36_DEV_MODE_REG, &data_buf);
            ESP_LOGI(TAG, "\tDevice mode: 0x%02x", data_buf);

            ft6x06_i2c_read8(dev_addr, FT6X36_FIRMWARE_ID_REG, &data_buf);
            ESP_LOGI(TAG, "\tFirmware ID: 0x%02x", data_buf);

            ft6x06_i2c_read8(dev_addr, FT6X36_RELEASECODE_REG, &data_buf);
            ESP_LOGI(TAG, "\tRelease code: 0x%02x", data_buf);
        }
    }
}

/**
  * @brief  Get the touch screen X and Y positions values. Ignores multi touch
  * @param  drv:
  * @param  data: Store data here
  * @retval Always false
  */
bool ft6x36_read(lv_indev_drv_t *drv, lv_indev_data_t *data) {
    uint8_t data_xy[4];        // 2 bytes X | 2 bytes Y
    uint8_t touch_pnt_cnt;        // Number of detected touch points
    static int16_t last_x = 0;  // 12bit pixel value
    static int16_t last_y = 0;  // 12bit pixel value

    ft6x06_i2c_read8(current_dev_addr, FT6X36_TD_STAT_REG, &touch_pnt_cnt);
    if (touch_pnt_cnt != 1) {    // ignore no touch & multi touch
        data->point.x = last_x;
        data->point.y = last_y;
        data->state = LV_INDEV_STATE_REL;
        return false;
    }

    // Read X value
    i2c_cmd_handle_t i2c_cmd = i2c_cmd_link_create();

    i2c_master_start(i2c_cmd);
    i2c_master_write_byte(i2c_cmd, (current_dev_addr << 1) | I2C_MASTER_WRITE, true);
    i2c_master_write_byte(i2c_cmd, FT6X36_P1_XH_REG, I2C_MASTER_ACK);

    i2c_master_start(i2c_cmd);
    i2c_master_write_byte(i2c_cmd, (current_dev_addr << 1) | I2C_MASTER_READ, true);

    i2c_master_read_byte(i2c_cmd, &data_xy[0], I2C_MASTER_ACK);     // reads FT6X36_P1_XH_REG
    i2c_master_read_byte(i2c_cmd, &data_xy[1], I2C_MASTER_NACK);    // reads FT6X36_P1_XL_REG
    i2c_master_stop(i2c_cmd);
    esp_err_t ret = i2c_master_cmd_begin(TOUCH_I2C_PORT, i2c_cmd, 1000 / portTICK_RATE_MS);
    i2c_cmd_link_delete(i2c_cmd);
    if (ret != ESP_OK) {
        ESP_LOGE(TAG, "Error getting X coordinates: %s", esp_err_to_name(ret));
        data->point.x = last_x;
        data->point.y = last_y;
        data->state = LV_INDEV_STATE_REL;   // no touch detected
        return false;
    }

    // Read Y value
    i2c_cmd = i2c_cmd_link_create();

    i2c_master_start(i2c_cmd);
    i2c_master_write_byte(i2c_cmd, (current_dev_addr << 1) | I2C_MASTER_WRITE, true);
    i2c_master_write_byte(i2c_cmd, FT6X36_P1_YH_REG, I2C_MASTER_ACK);

    i2c_master_start(i2c_cmd);
    i2c_master_write_byte(i2c_cmd, (current_dev_addr << 1) | I2C_MASTER_READ, true);

    i2c_master_read_byte(i2c_cmd, &data_xy[2], I2C_MASTER_ACK);     // reads FT6X36_P1_YH_REG
    i2c_master_read_byte(i2c_cmd, &data_xy[3], I2C_MASTER_NACK);    // reads FT6X36_P1_YL_REG
    i2c_master_stop(i2c_cmd);
    ret = i2c_master_cmd_begin(TOUCH_I2C_PORT, i2c_cmd, 1000 / portTICK_RATE_MS);
    i2c_cmd_link_delete(i2c_cmd);
    if (ret != ESP_OK) {
        ESP_LOGE(TAG, "Error getting Y coordinates: %s", esp_err_to_name(ret));
        data->point.x = last_x;
        data->point.y = last_y;
        data->state = LV_INDEV_STATE_REL;   // no touch detected
        return false;
    }

    last_x = ((data_xy[0] & FT6X36_MSB_MASK) << 8) | (data_xy[1] & FT6X36_LSB_MASK);
    last_y = ((data_xy[2] & FT6X36_MSB_MASK) << 8) | (data_xy[3] & FT6X36_LSB_MASK);

#if CONFIG_LV_FT6X36_INVERT_X
    last_x =  LV_HOR_RES - last_x;
#endif
#if CONFIG_LV_FT6X36_INVERT_Y
    last_y = LV_VER_RES - last_y;
#endif
#if CONFIG_LV_FT6X36_SWAPXY
    int16_t swap_buf = last_x;
    last_x = last_y;
    last_y = swap_buf;
#endif
    data->point.x = last_x;
    data->point.y = last_y;
    data->state = LV_INDEV_STATE_PR;
    ESP_LOGD(TAG, "X=%u Y=%u", data->point.x, data->point.y);
    return false;
}