/*
 * Copyright (c) 2025 Qingsong Gou <gouqs@hotmail.com>
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#define DT_DRV_COMPAT focaltech_ft6146

#include <zephyr/kernel.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/input/input.h>
#include <zephyr/input/input_touch.h>
#include <zephyr/logging/log.h>

LOG_MODULE_REGISTER(ft6146, CONFIG_INPUT_LOG_LEVEL);

/* FT6146 register definitions */
#define FT6146_REG_DEVICE_MODE            0x00
#define FT6146_REG_GEST_ID                0x01
#define FT6146_REG_TD_STATUS              0x02
#define FT6146_REG_P1_XH                  0x03
#define FT6146_REG_P1_XL                  0x04
#define FT6146_REG_P1_YH                  0x05
#define FT6146_REG_P1_YL                  0x06
#define FT6146_REG_P1_WEIGHT              0x07
#define FT6146_REG_P1_MISC                0x08
#define FT6146_REG_P2_XH                  0x09
#define FT6146_REG_P2_XL                  0x0A
#define FT6146_REG_P2_YH                  0x0B
#define FT6146_REG_P2_YL                  0x0C
#define FT6146_REG_P2_WEIGHT              0x0D
#define FT6146_REG_P2_MISC                0x0E
#define FT6146_REG_THRESHOLD              0x80
#define FT6146_REG_FILTER_COE             0x85
#define FT6146_REG_CTRL                   0x86
#define FT6146_REG_TIMEENTERMONITOR       0x87
#define FT6146_REG_PERIODACTIVE           0x88
#define FT6146_REG_PERIODMONITOR          0x89
#define FT6146_REG_RADIAN_VALUE           0x91
#define FT6146_REG_OFFSET_LEFT_RIGHT      0x92
#define FT6146_REG_OFFSET_UP_DOWN         0x93
#define FT6146_REG_DIST_LEFT_RIGHT        0x94
#define FT6146_REG_DIST_UP_DOWN           0x95
#define FT6146_REG_ZOOM_DIS_SQR           0x96
#define FT6146_REG_RADIAN_THRESHOLD       0x97
#define FT6146_REG_SMALL_OBJECT_THRESHOLD 0x98

/* Device mode values */
#define FT6146_DEVICE_MODE_NORMAL 0x00
#define FT6146_DEVICE_MODE_TEST   0x04
#define FT6146_DEVICE_MODE_SYSTEM 0x01

/* Gesture IDs */
#define FT6146_GESTURE_NO_GESTURE 0x00
#define FT6146_GESTURE_MOVE_UP    0x10
#define FT6146_GESTURE_MOVE_RIGHT 0x14
#define FT6146_GESTURE_MOVE_DOWN  0x18
#define FT6146_GESTURE_MOVE_LEFT  0x1C
#define FT6146_GESTURE_ZOOM_IN    0x48
#define FT6146_GESTURE_ZOOM_OUT   0x49

/* Reset timing */
#define FT6146_RESET_DELAY_MS      10
#define FT6146_POST_RESET_DELAY_MS 100

#define CTP_DOWN    (0U)
#define CTP_UP      (1U)
#define CTP_MOVE    (2U)
#define CTP_RESERVE (3U)

#define POSITION_H_MSK          0x0FU
#define EVENT_FLAG_MASK         0xC0U

struct ft6146_data {
	const struct device *dev;
	struct gpio_callback int_cb;
	struct k_work work;
	struct k_timer poll_timer;
};

struct ft6146_config {
	struct input_touchscreen_common_config common;
	struct i2c_dt_spec i2c;
	struct gpio_dt_spec reset_gpio;
#ifdef CONFIG_INPUT_FT6146_INTERRUPT
	struct gpio_dt_spec int_gpio;
#endif
};

INPUT_TOUCH_STRUCT_CHECK(struct ft6146_config);

static void ft6146_process_touch(const struct device *dev, uint8_t status)
{
	const struct ft6146_config *config = dev->config;
	uint8_t point_data[9];
	uint8_t event_flag;
	uint16_t x, y;
	int ret;

	/* Read touch data */
	ret = i2c_burst_read_dt(&config->i2c, FT6146_REG_DEVICE_MODE, point_data,
				sizeof(point_data));
	if (ret < 0) {
		LOG_ERR("Failed to read touch data: %d", ret);
		return;
	}

	event_flag = FIELD_GET(EVENT_FLAG_MASK, point_data[FT6146_REG_P1_XH]);
	x = ((point_data[FT6146_REG_P1_XH] & POSITION_H_MSK) << 8) + point_data[FT6146_REG_P1_XL];
	y = ((point_data[FT6146_REG_P1_YH] & POSITION_H_MSK) << 8) + point_data[FT6146_REG_P1_YL];

	LOG_DBG("event_flag:%d, x:%d, y:%d", event_flag, x, y);
	if ((event_flag == CTP_DOWN) || (event_flag == CTP_MOVE)) {
		input_touchscreen_report_pos(dev, x, y, K_FOREVER);
		input_report_key(dev, INPUT_BTN_TOUCH, 1, true, K_FOREVER);
	} else if (event_flag == CTP_UP) {
		input_report_key(dev, INPUT_BTN_TOUCH, 0, true, K_FOREVER);
	}
}

static void ft6146_work_handler(struct k_work *work)
{
	struct ft6146_data *data = CONTAINER_OF(work, struct ft6146_data, work);
	const struct device *dev = data->dev;

	ft6146_process_touch(dev, 0);
}

#ifndef CONFIG_INPUT_FT6146_INTERRUPT
static void ft6146_poll_timer_handler(struct k_timer *timer)
{
	struct ft6146_data *data = CONTAINER_OF(timer, struct ft6146_data, poll_timer);

	k_work_submit(&data->work);
}
#else
static void ft6146_isr_handler(const struct device *dev, struct gpio_callback *cb, uint32_t pins)
{
	struct ft6146_data *data = CONTAINER_OF(cb, struct ft6146_data, int_cb);

	k_work_submit(&data->work);
}
#endif

static int ft6146_reset(const struct device *dev)
{
	const struct ft6146_config *config = dev->config;
	int ret;

	if (!config->reset_gpio.port) {
		return 0;
	}

	if (!device_is_ready(config->reset_gpio.port)) {
		LOG_ERR("Reset GPIO not ready");
		return -ENODEV;
	}

	ret = gpio_pin_configure_dt(&config->reset_gpio, GPIO_OUTPUT_ACTIVE);
	if (ret < 0) {
		LOG_ERR("Failed to configure reset GPIO: %d", ret);
		return ret;
	}

	k_msleep(FT6146_RESET_DELAY_MS);

	/* De-assert reset */
	ret = gpio_pin_set_dt(&config->reset_gpio, 0);
	if (ret < 0) {
		LOG_ERR("Failed to de-assert reset: %d", ret);
		return ret;
	}

	k_msleep(FT6146_POST_RESET_DELAY_MS);

	return ret;
}

static int ft6146_init(const struct device *dev)
{
	const struct ft6146_config *config = dev->config;
	struct ft6146_data *data = dev->data;
	int ret;

	if (!i2c_is_ready_dt(&config->i2c)) {
		LOG_ERR("I2C bus not ready");
		return -ENODEV;
	}

	data->dev = dev;

	/* Perform reset sequence */
	ret = ft6146_reset(dev);
	if (ret < 0) {
		return ret;
	}

	/* Initialize work queue */
	k_work_init(&data->work, ft6146_work_handler);

#ifdef CONFIG_INPUT_FT6146_INTERRUPT
	if (!gpio_is_ready_dt(&config->int_gpio)) {
		LOG_ERR("Interrupt GPIO controller device not ready");
		return -ENODEV;
	}

	ret = gpio_pin_configure_dt(&config->int_gpio, GPIO_INPUT);
	if (ret < 0) {
		LOG_ERR("Failed to configure interrupt GPIO: %d", ret);
		return ret;
	}

	ret = gpio_pin_interrupt_configure_dt(&config->int_gpio, GPIO_INT_EDGE_TO_ACTIVE);
	if (ret < 0) {
		LOG_ERR("Failed to configure interrupt: %d", ret);
		return ret;
	}

	gpio_init_callback(&data->int_cb, ft6146_isr_handler, BIT(config->int_gpio.pin));
	ret = gpio_add_callback(config->int_gpio.port, &data->int_cb);
	if (ret < 0) {
		LOG_ERR("Failed to add callback: %d", ret);
		return ret;
	}
#else
	/* Initialize polling timer */
	k_timer_init(&data->poll_timer, ft6146_poll_timer_handler, NULL);
	k_timer_start(&data->poll_timer, K_MSEC(CONFIG_INPUT_FT6146_PERIOD),
		      K_MSEC(CONFIG_INPUT_FT6146_PERIOD));
#endif

	return ret;
}

#define FT6146_INIT(n)                                                                             \
	static struct ft6146_data ft6146_data_##n;                                                 \
                                                                                                   \
	static const struct ft6146_config ft6146_config_##n = {                                    \
		.common = INPUT_TOUCH_DT_INST_COMMON_CONFIG_INIT(n),                               \
		.i2c = I2C_DT_SPEC_INST_GET(n),                                                    \
		.reset_gpio = GPIO_DT_SPEC_INST_GET_OR(n, reset_gpios, {0}),                       \
		COND_CODE_1(CONFIG_INPUT_FT6146_INTERRUPT,                                         \
		(.int_gpio = GPIO_DT_SPEC_INST_GET(n, int_gpios),), ()) };                         \
                                                                                                   \
	DEVICE_DT_INST_DEFINE(n, ft6146_init, NULL, &ft6146_data_##n, &ft6146_config_##n,          \
			      POST_KERNEL, CONFIG_INPUT_INIT_PRIORITY, NULL);

DT_INST_FOREACH_STATUS_OKAY(FT6146_INIT)