#include "esp_check.h"
#include "esp_log.h"

#include "i2c_bus.h"

static const char *TAG = "i2c_bus";

/*
 * CrowPanel 7" Advance pins. The Basic model uses 19/20 instead -- and on the
 * ESP32-S3 those are the native USB D-/D+ pins, which is a separate trap.
 */
#define I2C_BUS_SDA_GPIO 15
#define I2C_BUS_SCL_GPIO 16
#define I2C_BUS_PORT     I2C_NUM_0

static i2c_master_bus_handle_t bus = NULL;

esp_err_t i2c_bus_init(void)
{
    if (bus != NULL) {
        return ESP_OK;
    }

    const i2c_master_bus_config_t cfg = {
        .i2c_port = I2C_BUS_PORT,
        .sda_io_num = I2C_BUS_SDA_GPIO,
        .scl_io_num = I2C_BUS_SCL_GPIO,
        .clk_source = I2C_CLK_SRC_DEFAULT,
        .glitch_ignore_cnt = 7,
        .flags.enable_internal_pullup = true,
    };

    ESP_RETURN_ON_ERROR(i2c_new_master_bus(&cfg, &bus), TAG, "i2c bus init failed");
    ESP_LOGI(TAG, "I2C bus up on SDA=%d SCL=%d", I2C_BUS_SDA_GPIO, I2C_BUS_SCL_GPIO);
    return ESP_OK;
}

i2c_master_bus_handle_t i2c_bus_get(void)
{
    return bus;
}

void i2c_bus_scan(const char *tag)
{
    if (bus == NULL) {
        ESP_LOGW(tag, "I2C bus not initialized");
        return;
    }

    int n = 0;
    for (uint8_t addr = 0x03; addr < 0x78; addr++) {
        if (i2c_master_probe(bus, addr, 20) == ESP_OK) {
            const char *what = "?";
            if (addr == 0x30) what = "STC8H1K28 board controller";
            else if (addr == 0x5D || addr == 0x14) what = "GT911 touch";
            ESP_LOGI(tag, "  I2C 0x%02X  %s", addr, what);
            n++;
        }
    }
    ESP_LOGI(tag, "  %d device(s) on the bus", n);
}