#include <errno.h>
#include <stdbool.h>
#include <stdint.h>

#include <zephyr/device.h>
#include <zephyr/drivers/power/ip5306.h>
#include <zephyr/logging/log.h>
#include <zephyr/sys/util.h>

#include "ip5306_priv.h"

#if IS_ENABLED(CONFIG_IP5306_KEEPALIVE_HW_NRF)
#include <soc_nrf_common.h>
#define IP5306_CFG_KEEPALIVE_PSEL_INIT(inst) \
	.keepalive_psel = NRF_DT_GPIOS_TO_PSEL_OR(DT_DRV_INST(inst), keepalive_gpios, 0),
#else
#define IP5306_CFG_KEEPALIVE_PSEL_INIT(inst)
#endif

LOG_MODULE_REGISTER(ip5306, LOG_LEVEL_INF);

#define DT_DRV_COMPAT injoinic_ip5306

#define IP5306_REG_READ0 0x70
#define IP5306_REG_READ1 0x71
#define IP5306_STATUS_BIT BIT(3)

static int ip5306_read_reg(const struct device *dev, uint8_t reg, uint8_t *val)
{
	const struct ip5306_config *cfg = dev->config;

	return i2c_reg_read_byte_dt(&cfg->i2c, reg, val);
}

static int ip5306_get_status_bit(const struct device *dev, uint8_t reg, bool *flag)
{
	uint8_t value = 0U;
	int ret;

	if (flag == NULL) {
		return -EINVAL;
	}

	ret = ip5306_read_reg(dev, reg, &value);
	if (ret != 0) {
		return ret;
	}

	*flag = ((value & IP5306_STATUS_BIT) != 0U);
	return 0;
}

static int ip5306_api_is_charging(const struct device *dev, bool *charging)
{
	return ip5306_get_status_bit(dev, IP5306_REG_READ0, charging);
}

static int ip5306_api_is_charge_full(const struct device *dev, bool *full)
{
	return ip5306_get_status_bit(dev, IP5306_REG_READ1, full);
}

static void ip5306_keepalive_start(const struct device *dev)
{
	struct ip5306_data *data = dev->data;
	const struct ip5306_config *cfg = dev->config;

	if (!cfg->has_keepalive_gpio || (data->keepalive_interval_ms == 0U)) {
		data->backend = IP5306_KEEPALIVE_BACKEND_NONE;
		return;
	}

	/*
	 * 选择策略：
	 * 1) DTS 显式请求硬件 offload 时，先尝试硬件后端；
	 * 2) 若硬件依赖不可用或资源被占用，则告警后回退软件后端。
	 */
	if (cfg->keepalive_offload) {
#if IS_ENABLED(CONFIG_IP5306_KEEPALIVE_HW_NRF)
		int ret = ip5306_keepalive_hw_nrf_start(dev);

		if (ret == 0) {
			LOG_INF("Keepalive backend=HW(nRF), pulse=%ums interval=%ums",
				data->keepalive_pulse_ms, data->keepalive_interval_ms);
			return;
		}

		LOG_WRN("HW keepalive unavailable (%d), fallback to SW backend", ret);
#else
		LOG_WRN("HW keepalive requested but HW backend is not built, fallback to SW backend");
#endif
	}
	

	ip5306_keepalive_sw_start(dev);
	LOG_INF("Keepalive backend=SW, pulse=%ums interval=%ums",
		data->keepalive_pulse_ms, data->keepalive_interval_ms);
}

static int ip5306_init(const struct device *dev)
{
	const struct ip5306_config *cfg = dev->config;
	struct ip5306_data *data = dev->data;

	if (!i2c_is_ready_dt(&cfg->i2c)) {
		return -ENODEV;
	}

	if (cfg->has_keepalive_gpio) {
		if (!gpio_is_ready_dt(&cfg->keepalive_gpio)) {
			return -ENODEV;
		}

		if (gpio_pin_configure_dt(&cfg->keepalive_gpio, GPIO_OUTPUT_INACTIVE) != 0) {
			return -EIO;
		}
	}

	data->keepalive_high = false;
	data->dev = dev;
	data->backend = IP5306_KEEPALIVE_BACKEND_NONE;
	data->keepalive_pulse_ms = (cfg->keepalive_pulse_ms != 0U) ?
		cfg->keepalive_pulse_ms : IP5306_KEEPALIVE_DEFAULT_PULSE_MS;
	data->keepalive_interval_ms = (cfg->keepalive_interval_ms != 0U) ?
		cfg->keepalive_interval_ms : IP5306_KEEPALIVE_DEFAULT_INTERVAL_MS;

	ip5306_keepalive_start(dev);

	return 0;
}

static const struct ip5306_driver_api ip5306_api = {
	.is_charging = ip5306_api_is_charging,
	.is_charge_full = ip5306_api_is_charge_full,
};

#define IP5306_DEFINE(inst)                                                                      \
	static struct ip5306_data ip5306_data_##inst;                                                \
	static const struct ip5306_config ip5306_cfg_##inst = {                                      \
		.i2c = I2C_DT_SPEC_INST_GET(inst),                                                       \
		.keepalive_gpio = GPIO_DT_SPEC_INST_GET_OR(inst, keepalive_gpios, {0}),                  \
		IP5306_CFG_KEEPALIVE_PSEL_INIT(inst)                                                     \
		.keepalive_pulse_ms = DT_INST_PROP(inst, keepalive_pulse_ms),                            \
		.keepalive_interval_ms = DT_INST_PROP(inst, keepalive_interval_ms),                      \
		.has_keepalive_gpio = DT_INST_NODE_HAS_PROP(inst, keepalive_gpios),                      \
		.keepalive_offload = DT_INST_PROP_OR(inst, keepalive_offload, false),                    \
	};                                                                                           \
	DEVICE_DT_INST_DEFINE(inst, ip5306_init, NULL, &ip5306_data_##inst,                          \
			      &ip5306_cfg_##inst, POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, \
			      &ip5306_api);

DT_INST_FOREACH_STATUS_OKAY(IP5306_DEFINE)