#include <esp_wifi.h>
#include <esp_event.h>
#include <esp_log.h>
#include <esp_system.h>
#include <nvs_flash.h>
#include <sys/param.h>
#include "esp_netif.h"
#include "esp_eth.h"
#include "protocol_examples_common.h"

#include <esp_http_server.h>
#include "bme280.h"

static const char *TAG = "BME280";

static esp_err_t bme280_readout_handler(httpd_req_t *req);
static httpd_handle_t start_webserver(void);
static void stop_webserver(httpd_handle_t server);
static void disconnect_handler(void* arg, esp_event_base_t event_base, 
      int32_t event_id, void* event_data);
static void connect_handler(void* arg, esp_event_base_t event_base, 
      int32_t event_id, void* event_data);

static const httpd_uri_t bme280_uri = {
   .uri       = "/bme280",
   .method    = HTTP_GET,
   .handler   = bme280_readout_handler
};


void setup_i2c(void);
int8_t init_bme280(void);
int8_t bme280_readout();
int8_t lastReadoutStatus = 1;
extern struct bme280_dev bme280; // from bme280_sup.c

void app_main(void)
{
   static httpd_handle_t server = NULL;

   ESP_ERROR_CHECK(nvs_flash_init());
   ESP_ERROR_CHECK(esp_netif_init());
   ESP_ERROR_CHECK(esp_event_loop_create_default());

   /* Register event handlers to start server when Wi-Fi or Ethernet is connected,
    * and stop server when disconnection happens.
    */

#ifdef CONFIG_EXAMPLE_CONNECT_WIFI
   ESP_ERROR_CHECK(esp_event_handler_register(IP_EVENT, IP_EVENT_STA_GOT_IP, &connect_handler, &server));
   ESP_ERROR_CHECK(esp_event_handler_register(WIFI_EVENT, WIFI_EVENT_STA_DISCONNECTED, &disconnect_handler, &server));
#endif // CONFIG_EXAMPLE_CONNECT_WIFI
#ifdef CONFIG_EXAMPLE_CONNECT_ETHERNET
   ESP_ERROR_CHECK(esp_event_handler_register(IP_EVENT, IP_EVENT_ETH_GOT_IP, &connect_handler, &server));
   ESP_ERROR_CHECK(esp_event_handler_register(ETH_EVENT, ETHERNET_EVENT_DISCONNECTED, &disconnect_handler, &server));
#endif // CONFIG_EXAMPLE_CONNECT_ETHERNET

   /* This helper function configures Wi-Fi or Ethernet, as selected in menuconfig.
    * Read "Establishing Wi-Fi or Ethernet Connection" section in
    * examples/protocols/README.md for more information about this function.
    */
   ESP_ERROR_CHECK(example_connect());

   setup_i2c();
   int8_t ret = init_bme280();
   printf("BME init result %d\n", ret);

   /* while(1) {  */
      /* lastReadoutStatus = bme280_readout(); */
      /* vTaskDelay(1600/portTICK_PERIOD_MS); */
   /* } */
}

struct bme280_data comp_data;
int8_t bme280_readout(){
   int8_t ret;
   char msgbuf[128];
   ret = bme280_set_sensor_mode(BME280_NORMAL_MODE, &bme280);
   bme280.delay_ms(40);
   ret = bme280_get_sensor_data(BME280_ALL, &comp_data, &bme280);
   if (ret != BME280_OK)
      ESP_LOGI(TAG, "bme280_get_sensor_data() returned %d", ret);

   snprintf(msgbuf, sizeof(msgbuf), "%.1f C, %0.1f hPa, %0.1f%%",
         comp_data.temperature, comp_data.pressure / 100., comp_data.humidity);
   ESP_LOGI(TAG, "%s", msgbuf);

   return ret;
}

static esp_err_t bme280_readout_handler(httpd_req_t *req)
{
   char buffer[128];
   httpd_resp_set_type(req, "text/json");
   int8_t ret = bme280_readout();
   if (ret == 0) {
      snprintf(buffer, sizeof(buffer), "{\"status\": \"ok\", \"sensor\": \"bedroom-bme280-01\", \"temp\": %.2f, \"humidity\": %.2f, \"pressure\": %0.2f}",
            comp_data.temperature, comp_data.humidity, comp_data.pressure/100.);
      ESP_LOGI(TAG, "%s", buffer);
      httpd_resp_send(req, buffer, -1);
   }
   else {
      ESP_LOGE(TAG, "bme280_readout failed");
      httpd_resp_send(req, "{\"status\": failed, \"error\": \"could not read from sensor\"}", -1);
   }

   return ESP_OK;
}

static httpd_handle_t start_webserver(void)
{
   httpd_handle_t server = NULL;

   // Start the httpd server
   ESP_LOGI(TAG, "Starting server");

   httpd_config_t conf = HTTPD_DEFAULT_CONFIG();

   esp_err_t ret = httpd_start(&server, &conf);
   if (ESP_OK != ret) {
      ESP_LOGI(TAG, "Error starting server!");
      return NULL;
   }

   // Set URI handlers
   ESP_LOGI(TAG, "Registering URI handlers");
   httpd_register_uri_handler(server, &bme280_uri);
   return server;
}

static void stop_webserver(httpd_handle_t server)
{
   httpd_stop(server);
}

static void disconnect_handler(void* arg, esp_event_base_t event_base, 
      int32_t event_id, void* event_data)
{
   httpd_handle_t* server = (httpd_handle_t*) arg;
   if (*server) {
      stop_webserver(*server);
      *server = NULL;
   }
}

static void connect_handler(void* arg, esp_event_base_t event_base, 
      int32_t event_id, void* event_data)
{
   httpd_handle_t* server = (httpd_handle_t*) arg;
   if (*server == NULL) {
      *server = start_webserver();
   }
}