#include <stdio.h>
#include <string.h>
#include <inttypes.h>
#include "sdkconfig.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_chip_info.h"
#include "esp_flash.h"
#include "esp_system.h"

#include "esp_log.h"
#include "esp_event.h"
#include "esp_netif.h"
#include "nvs_flash.h"

#include "driver/spi_master.h"

#include "esp_eth.h"
#include "esp_eth_mac.h"
#include "esp_eth_phy.h"
#include "esp_eth_com.h"

#include "esp_eth_mac_w5500.h"
#include "esp_eth_phy_w5500.h"

static const char *TAG = "INETMON";

// -------------------- PIN CONFIG --------------------
#define PIN_SCK   12
#define PIN_MOSI  11
#define PIN_MISO  13
#define PIN_CS    10
#define PIN_RST   9
#define PIN_INT   14

static esp_eth_handle_t eth_handle = NULL;


// -------------------- EVENT HANDLER --------------------
static void eth_event_handler(void *arg, esp_event_base_t event_base,
                              int32_t event_id, void *event_data)
{
    switch (event_id) {

        case ETHERNET_EVENT_CONNECTED:
            ESP_LOGI(TAG, "Ethernet LINK UP");
            break;

        case ETHERNET_EVENT_DISCONNECTED:
            ESP_LOGI(TAG, "Ethernet LINK DOWN");
            break;

        case ETHERNET_EVENT_START:
            ESP_LOGI(TAG, "Ethernet START");
            break;

        case ETHERNET_EVENT_STOP:
            ESP_LOGI(TAG, "Ethernet STOP");
            break;

        default:
            break;
    }
}

static void got_ip_event_handler(void *arg, esp_event_base_t event_base,
                                 int32_t event_id, void *event_data)
{
    ip_event_got_ip_t *event = (ip_event_got_ip_t *)event_data;

    ESP_LOGI(
        TAG,
        "IP: " IPSTR " GW: " IPSTR " MASK: " IPSTR,
        IP2STR(&event->ip_info.ip),
        IP2STR(&event->ip_info.gw),
        IP2STR(&event->ip_info.netmask)
    );
}

extern "C" void app_main(void)
{
    printf("Hello world!\n");

    /* Print chip information */
    esp_chip_info_t chip_info;
    uint32_t flash_size;
    esp_chip_info(&chip_info);
    printf("This is %s chip with %d CPU core(s), %s%s%s%s, ",
           CONFIG_IDF_TARGET,
           chip_info.cores,
           (chip_info.features & CHIP_FEATURE_WIFI_BGN) ? "WiFi/" : "",
           (chip_info.features & CHIP_FEATURE_BT) ? "BT" : "",
           (chip_info.features & CHIP_FEATURE_BLE) ? "BLE" : "",
           (chip_info.features & CHIP_FEATURE_IEEE802154) ? ", 802.15.4 (Zigbee/Thread)" : ""
    );

    unsigned major_rev = chip_info.revision / 100;
    unsigned minor_rev = chip_info.revision % 100;
    printf("silicon revision v%d.%d, ", major_rev, minor_rev);
    if(esp_flash_get_size(NULL, &flash_size) != ESP_OK) {
        printf("Get flash size failed");
        return;
    }

    printf("%" PRIu32 "MB %s flash\n", flash_size / (uint32_t)(1024 * 1024),
           (chip_info.features & CHIP_FEATURE_EMB_FLASH) ? "embedded" : "external");

    printf("Minimum free heap size: %" PRIu32 " bytes\n", esp_get_minimum_free_heap_size());

    fflush(stdout);

    ESP_LOGI(TAG, "Starting W5500 Ethernet...");

    // NVS + event loop
    ESP_ERROR_CHECK(nvs_flash_init());
    ESP_ERROR_CHECK(esp_netif_init());
    ESP_ERROR_CHECK(esp_event_loop_create_default());

    esp_event_handler_register(ETH_EVENT, ESP_EVENT_ANY_ID, &eth_event_handler, NULL);
    esp_event_handler_register(IP_EVENT, IP_EVENT_ETH_GOT_IP, &got_ip_event_handler, NULL);

    // ---------------- SPI BUS ----------------
    spi_bus_config_t buscfg = {};

    buscfg.mosi_io_num = PIN_MOSI;
    buscfg.miso_io_num = PIN_MISO;
    buscfg.sclk_io_num = PIN_SCK;

    buscfg.quadwp_io_num = -1;
    buscfg.quadhd_io_num = -1;

    buscfg.data4_io_num = -1;
    buscfg.data5_io_num = -1;
    buscfg.data6_io_num = -1;
    buscfg.data7_io_num = -1;

    buscfg.max_transfer_sz = 0;
    buscfg.flags = 0;
    buscfg.isr_cpu_id = ESP_INTR_CPU_AFFINITY_AUTO;
    buscfg.intr_flags = 0;

    ESP_ERROR_CHECK(
        spi_bus_initialize(SPI2_HOST, &buscfg, SPI_DMA_CH_AUTO)
    );

    // ---------------- SPI DEVICE CONFIG ----------------
    spi_device_interface_config_t spi_devcfg = {};

    spi_devcfg.command_bits = 16;
    spi_devcfg.address_bits = 8;
    spi_devcfg.mode = 0;

    spi_devcfg.clock_speed_hz = 5 * 1000 * 1000;

    spi_devcfg.spics_io_num = PIN_CS;
    spi_devcfg.queue_size = 20;

    // ---------------- W5500 CONFIG ----------------
    eth_w5500_config_t w5500_config =
        ETH_W5500_DEFAULT_CONFIG(SPI2_HOST, &spi_devcfg);

    w5500_config.int_gpio_num = PIN_INT;

    // ---------------- MAC / PHY ----------------
    eth_mac_config_t mac_config = ETH_MAC_DEFAULT_CONFIG();
    eth_phy_config_t phy_config = ETH_PHY_DEFAULT_CONFIG();

    phy_config.reset_gpio_num = PIN_RST;

    // ---------------- CREATE MAC + PHY ----------------
    esp_eth_mac_t *mac =
        esp_eth_mac_new_w5500(&w5500_config, &mac_config);

    esp_eth_phy_t *phy =
        esp_eth_phy_new_w5500(&phy_config);

    esp_eth_config_t eth_config =
        ETH_DEFAULT_CONFIG(mac, phy);

    ESP_ERROR_CHECK(
        esp_eth_driver_install(&eth_config, &eth_handle)
    );

    uint8_t mac_addr[6];
    ESP_ERROR_CHECK(
        esp_eth_ioctl(
            eth_handle,
            ETH_CMD_G_MAC_ADDR,
            mac_addr
        )
    );

    ESP_LOGI(
        TAG,
        "Ethernet MAC: %02X:%02X:%02X:%02X:%02X:%02X",
        mac_addr[0],
        mac_addr[1],
        mac_addr[2],
        mac_addr[3],
        mac_addr[4],
        mac_addr[5]
    );

    // ---------------- NETWORK INTERFACE ----------------
    esp_netif_config_t cfg = ESP_NETIF_DEFAULT_ETH();
    esp_netif_t *eth_netif = esp_netif_new(&cfg);

    ESP_ERROR_CHECK(
        esp_netif_attach(
            eth_netif,
            esp_eth_new_netif_glue(eth_handle)
        )
    );

    // ---------------- START ETH ----------------
    ESP_ERROR_CHECK(esp_eth_start(eth_handle));

    ESP_LOGI(TAG, "W5500 init complete, waiting for DHCP...");

    while (true) {
        vTaskDelay(pdMS_TO_TICKS(2000));
    }

    // printf("Restarting now.\n");
    // esp_restart();
}