#include "canbus.h"
#include <zephyr/logging/log.h>
#include <zephyr/kernel.h>
#include "settings.h"

const struct device *const can_dev = DEVICE_DT_GET(DT_CHOSEN(zephyr_canbus));

K_THREAD_STACK_DEFINE(rx_thread_stack, RX_THREAD_STACK_SIZE);

static uint8_t node_id = 12; // Default node ID

LOG_MODULE_REGISTER(canbus, CONFIG_LOG_CAN_LEVEL);

static int canbus_set(const char *key, size_t len, settings_read_cb read_cb, void *cb_arg)
{
    const char *next;
    int rc;

    // Handle setting values for CAN bus configuration
    LOG_DBG("Setting CAN bus configuration: key=%s, len=%zu", key, len);
    if (settings_name_steq(key, "node_id", &next) && next != NULL)
    {
        if (len != sizeof(node_id))
        {
            LOG_ERR("Invalid length for node_id setting: %zu", len);
            return -EINVAL; // Invalid argument
        }

        rc = read_cb(cb_arg, &node_id, sizeof(node_id));
        if (rc < 0)
        {
            LOG_ERR("Failed to read node_id setting: %d", rc);
            return rc; // Read error
        }
        LOG_DBG("Set CAN bus node ID to: %d", node_id);
    }
    return 0; // Return 0 on success
}

struct settings_handler canbus_settings_handler = {
    .name = "canbus",
    .h_set = canbus_set, // No settings set handler
};

int canbus_init(void)
{
    int rc;
    settings_subsys_init();
    settings_register(&canbus_settings_handler);
    settings_load();

    rc = settings_get_val_len("canbus/node_id");
    if (rc < 0)
    {
        LOG_ERR("Failed to check CAN bus settings: %d", rc);
        return rc;
    }

    else if (rc == 0)
    {
        LOG_WRN("No CAN bus node id found in settings, using default default (%d)", node_id);
        settings_save_one("canbus/node_id", &node_id, sizeof(node_id));
        if (rc < 0)
        {
            LOG_ERR("Failed to save default CAN bus node id: %d", rc);
            return rc;
        }
    }
    else
    {
        rc = settings_load_one("canbus/node_id", &node_id, sizeof(node_id));
        if (rc < 0)
        {
            LOG_ERR("Failed to load CAN bus node id from settings: %d", rc);
            return rc;
        }
        LOG_DBG("Loaded CAN bus node id: %d", node_id);
    }

    if (!device_is_ready(can_dev))
    {
        LOG_ERR("CAN device %s is not ready", can_dev->name);
        return -ENODEV;
    }

#ifdef CONFIG_LOOPBACK_MODE
    rc = can_set_mode(can_dev, CAN_MODE_LOOPBACK);
    if (rc != 0)
    {
        LOG_ERR("Failed to set CAN loopback mode: %d", rc);
        return rc;
    }
#endif
    return 0;
}