#include <esp_wifi.h>
#include <esp_event.h>
#include <esp_log.h>
#include <esp_system.h>
#include <esp_http_server.h>
#include <nvs_flash.h>
#include <sys/param.h>
#include <string.h>
#include "esp_eth.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"


#define EXAMPLE_ESP_WIFI_SSID      "softAP_SE"
#define EXAMPLE_ESP_WIFI_PASS      "SE_12345678"
#define EXAMPLE_MAX_STA_CONN       10

static const char *TAG = "softAP_WebServer";

/* An HTTP GET handler */
static esp_err_t hello_get_handler(httpd_req_t *req)
{
    char*  buf;
    size_t buf_len;

    /* Get header value string length and allocate memory for length + 1,
     * extra byte for null termination */
    buf_len = httpd_req_get_hdr_value_len(req, "Host") + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        /* Copy null terminated value string into buffer */
        if (httpd_req_get_hdr_value_str(req, "Host", buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found header => Host: %s", buf);
        }
        free(buf);
    }

    buf_len = httpd_req_get_hdr_value_len(req, "Test-Header-2") + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        if (httpd_req_get_hdr_value_str(req, "Test-Header-2", buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found header => Test-Header-2: %s", buf);
        }
        free(buf);
    }

    buf_len = httpd_req_get_hdr_value_len(req, "Test-Header-1") + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        if (httpd_req_get_hdr_value_str(req, "Test-Header-1", buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found header => Test-Header-1: %s", buf);
        }
        free(buf);
    }

    /* Read URL query string length and allocate memory for length + 1,
     * extra byte for null termination */
    buf_len = httpd_req_get_url_query_len(req) + 1;
    if (buf_len > 1) {
        buf = malloc(buf_len);
        if (httpd_req_get_url_query_str(req, buf, buf_len) == ESP_OK) {
            ESP_LOGI(TAG, "Found URL query => %s", buf);
            char param[32];
            /* Get value of expected key from query string */
            if (httpd_query_key_value(buf, "query1", param, sizeof(param)) == ESP_OK) {
                ESP_LOGI(TAG, "Found URL query parameter => query1=%s", param);
            }
            if (httpd_query_key_value(buf, "query3", param, sizeof(param)) == ESP_OK) {
                ESP_LOGI(TAG, "Found URL query parameter => query3=%s", param);
            }
            if (httpd_query_key_value(buf, "query2", param, sizeof(param)) == ESP_OK) {
                ESP_LOGI(TAG, "Found URL query parameter => query2=%s", param);
            }
        }
        free(buf);
    }

    /* Set some custom headers */
    httpd_resp_set_hdr(req, "Custom-Header-1", "Custom-Value-1");
    httpd_resp_set_hdr(req, "Custom-Header-2", "Custom-Value-2");

    /* Send response with custom headers and body set as the
     * string passed in user context*/
    const char* resp_str = (const char*) req->user_ctx;
    httpd_resp_send(req, resp_str, HTTPD_RESP_USE_STRLEN);

    /* After sending the HTTP response the old HTTP request
     * headers are lost. Check if HTTP request headers can be read now. */
    if (httpd_req_get_hdr_value_len(req, "Host") == 0) {
        ESP_LOGI(TAG, "Request headers lost");
    }
    return ESP_OK;
}


static const httpd_uri_t hello = {
    .uri       = "/hello",
    .method    = HTTP_GET,
    .handler   = hello_get_handler,
    .user_ctx  = "Hola Mundo!!"
};

static httpd_handle_t start_webserver(void)
{
    httpd_handle_t server = NULL;
    httpd_config_t config = HTTPD_DEFAULT_CONFIG();

    // Iniciar el servidor httpd 
    ESP_LOGI(TAG, "Iniciando el servidor en el puerto: '%d'", config.server_port);
    if (httpd_start(&server, &config) == ESP_OK) {
        // Manejadores de URI
        ESP_LOGI(TAG, "Registrando manejadores de URI");
        httpd_register_uri_handler(server, &hello);
        return server;
    }

    //ESP_LOGI(TAG, "Error starting server!");
    return NULL;
}

static void wifi_event_handler(void* arg, esp_event_base_t event_base, int32_t event_id, void* event_data)
{
    if (event_id == WIFI_EVENT_AP_STACONNECTED) {
        wifi_event_ap_staconnected_t* event = (wifi_event_ap_staconnected_t*) event_data;
        ESP_LOGI(TAG, "estacion %X:%X:%X:%X:%X:%X se unio, AID=%d", event->mac[5], event->mac[4],event->mac[3],event->mac[2],event->mac[1],event->mac[0], event->aid);
    } else if (event_id == WIFI_EVENT_AP_STADISCONNECTED) {
        wifi_event_ap_stadisconnected_t* event = (wifi_event_ap_stadisconnected_t*) event_data;
        ESP_LOGI(TAG, "estacion %X:%X:%X:%X:%X:%X se desconecto, AID=%d", event->mac[5], event->mac[4],event->mac[3],event->mac[2],event->mac[1],event->mac[0], event->aid);
    }
}

esp_err_t wifi_init_softap(void)
{
    esp_netif_create_default_wifi_ap();

    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK(esp_wifi_init(&cfg));

    ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, ESP_EVENT_ANY_ID, &wifi_event_handler, NULL));

    wifi_config_t wifi_config = {
        .ap = {
            .ssid = EXAMPLE_ESP_WIFI_SSID,
            .ssid_len = strlen(EXAMPLE_ESP_WIFI_SSID),
            .password = EXAMPLE_ESP_WIFI_PASS,
            .max_connection = EXAMPLE_MAX_STA_CONN,
            .authmode = WIFI_AUTH_WPA_WPA2_PSK
        },
    };
    if (strlen(EXAMPLE_ESP_WIFI_PASS) == 0) {
        wifi_config.ap.authmode = WIFI_AUTH_OPEN;
    }

    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_AP));
    ESP_ERROR_CHECK(esp_wifi_set_config(ESP_IF_WIFI_AP, &wifi_config));
    ESP_ERROR_CHECK(esp_wifi_start());

    ESP_LOGI(TAG, "Inicializacion de softAP terminada. SSID: %s password: %s",
             EXAMPLE_ESP_WIFI_SSID, EXAMPLE_ESP_WIFI_PASS);
    return ESP_OK;
}


void app_main(void)
{
    httpd_handle_t server = NULL;

    ESP_ERROR_CHECK(nvs_flash_init());
    esp_netif_init();

    ESP_ERROR_CHECK(esp_event_loop_create_default());

    ESP_LOGI(TAG, "init softAP");
    ESP_ERROR_CHECK(wifi_init_softap());

    server = start_webserver();
}