#include <ESP8266WiFi.h>
#include <ESP8266mDNS.h>
#include <ESP8266HTTPUpdateServer.h>
#include <ESP8266WebServer.h>
#include <WiFiManager.h>
#include <ArduinoJson.h>
#include <EEPROM.h>

#include "config.h"

//********* Config block *********//

uint8_t pins[LIGHTS_COUNT] = {12, 15, 13, 14};

IPAddress strip_ip   ( 192, 168,   0,  26); // choose an unique IP Adress
IPAddress gateway_ip ( 192, 168,   0,   1); // Router IP
IPAddress subnet_mask( 255, 255, 255,   0);
IPAddress dns        ( 192, 168,   0,   1);

//********************************//

#define LIGHT_VERSION 2.1

#define LAST_STATE_STARTUP_LIGHT_LAST_STATE 0
#define LAST_STATE_STARTUP_LIGHT_ON_STATE   1
#define LAST_STATE_STARTUP_LIGHT_OFF_STATE  2

#define LIGHT_STATE_ON  1
#define LIGHT_STATE_OFF 0

#define TIMING_CONTROL_ENABLED  1
#define TIMING_CONTROL_DISABLED 0

#define SCENE_RELEAX  0
#define SCENE_BRIGHT  1
#define SCENE_NIGHTLY 2

// 10 bit PWM
#define PWM_OFF               0 // 0V
#define PWM_MIN             640 // 15V - minimum light amount (~1%)
#define PWM_MAX            1023 // 24V - maximum light amount (100%)
#define BRI_TO_PWM_FACTOR 1.506 // 24V-15V = 9V range; 9V ≙ 1024-640 = 384 counts; 384/255 counts =~ 1,506 counts

//********************************//

uint8_t scene;
uint8_t tc_enabled;

bool light_state[LIGHTS_COUNT];
bool in_transition;

int transitiontime[LIGHTS_COUNT];
int bri[LIGHTS_COUNT];

float step_level[LIGHTS_COUNT];
float current_bri[LIGHTS_COUNT];
byte mac[6];

ESP8266WebServer server(80);
ESP8266HTTPUpdateServer httpUpdateServer;

uint32_t last_lightengine_activity = 0;

//********************************//

void apply_scene(uint8_t new_scene,  uint8_t light)
{
  if (new_scene == SCENE_RELEAX)
  {
    bri[light] = 144;
  } else if (new_scene == SCENE_BRIGHT)
  {
    bri[light] = 254;
  } else if (new_scene == SCENE_NIGHTLY)
  {
    bri[0] = 25;
    bri[1] =  0;
    bri[2] =  0;
    bri[3] =  0;
  }
}

//********************************//

void process_lightdata(uint8_t light, float transitiontime)
{
  transitiontime *= 16;
  if (light_state[light])
  {
    step_level[light] = (bri[light] - current_bri[light]) / transitiontime;
  } else {
    step_level[light] = current_bri[light] / transitiontime;
  }
}

//********************************//

void lightEngine()
{

  if (millis() < (last_lightengine_activity + TIME_LIGHTENGINE_INTERVAL_MS))
  {
    // abort processing, the transition setting is a delay of seconds
    return;
  }

  last_lightengine_activity = millis();

  for (int i = 0; i < LIGHTS_COUNT; i++) 
  {
    if (light_state[i])
    {
      if (bri[i] != current_bri[i])
      {
        in_transition = true;
        current_bri[i] += step_level[i] / 10.0;
        if ((step_level[i] > 0.0 && current_bri[i] > bri[i]) ||
            (step_level[i] < 0.0 && current_bri[i] < bri[i]))
        {
          current_bri[i] = bri[i];
        }

        uint16_t tmp_pwm = calcPWM(current_bri[i]);
        //Serial.println("pin" + (String)i + " = PWM(" + (String)tmp_pwm + ")");
        analogWrite(pins[i], tmp_pwm);
      }
    } else {

      if (current_bri[i] != 0)
      {
        in_transition = true;
        current_bri[i] -= step_level[i] / 10.0;
        if (current_bri[i] < 0)
        {
          current_bri[i] = 0;
        }

        uint16_t tmp_pwm = calcPWM(current_bri[i]);
        //Serial.println("pin" + (String)i + " = PWM(" + (String)tmp_pwm + ")");
        analogWrite(pins[i], tmp_pwm);
      }
    }
  }

  if (in_transition)
  {
    delay(6);
    in_transition = false;
  }
}

//********************************//

uint16_t calcPWM(float tbri)
{
  uint16_t tmp_pwm = PWM_OFF;
  if (tbri > 0.0)
  {
    tmp_pwm = PWM_MIN + (int)(tbri * BRI_TO_PWM_FACTOR);
  }
  if (tmp_pwm > PWM_MAX)
  {
    tmp_pwm = PWM_MAX;
  }
  //Serial.println((String)tbri + " => " + (String)tmp_pwm);
  return tmp_pwm;
}

//********************************//

void read_eeprom_config()
{
  for (uint8_t light = 0; light < LIGHTS_COUNT; light++)
  {
    apply_scene(EEPROM.read(EEPROM_SCENE_ADDRESS), light);
    step_level[light] = bri[light] / 150.0;

    if (EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS) == LAST_STATE_STARTUP_LIGHT_LAST_STATE ||
        (EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS) == LAST_STATE_STARTUP_LIGHT_ON_STATE &&
         EEPROM.read(EEPROM_LAST_STATE_ADDRESS + light) == LIGHT_STATE_ON))
    {
      light_state[light] = true; // set the light state to on
    }
  }

  uint8_t tmp = EEPROM.read(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS);
  if (tmp == TIMING_CONTROL_DISABLED)
  {
    tc_enabled = TIMING_CONTROL_DISABLED;

  } else if (tmp == TIMING_CONTROL_ENABLED)
  {
    tc_enabled = TIMING_CONTROL_ENABLED;
  
  } else {
  
    EEPROM.write(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS, TIMING_CONTROL_DISABLED);
    EEPROM.commit();
    tc_enabled = TIMING_CONTROL_DISABLED;
  }

  if (EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS) == 255)
  {
    // set the default value on uninitialized EEPROM
    EEPROM.write(EEPROM_LAST_STATE_STARTUP_ADDRESS, 0);
    EEPROM.commit();
  }

#ifdef USE_STATIC_IP
  if (EEPROM.read(EEPROM_DYNAMIC_IP_ADDRESS) == 255)
  {
    EEPROM.write(EEPROM_DYNAMIC_IP_ADDRESS, 0);
    EEPROM.commit();
  }
#else
  if (EEPROM.read(EEPROM_DYNAMIC_IP_ADDRESS) == 255)
  {
    EEPROM.write(EEPROM_DYNAMIC_IP_ADDRESS, 1);
    EEPROM.commit();
  }
#endif
}

//********************************//

void setup()
{
  EEPROM.begin(256);

  Serial.begin(SERIAL_BAUD_RATE);

  if (EEPROM.read(EEPROM_DYNAMIC_IP_ADDRESS) == 0)
  {
    WiFi.config(strip_ip, gateway_ip, subnet_mask, dns);
  }

  read_eeprom_config();

  for (int j = 0; j < 200; j++)
  {
    lightEngine();
  }

  WiFi.mode(WIFI_STA);
  WiFiManager wifiManager;
  wifiManager.setConfigPortalTimeout(120);
  wifiManager.autoConnect(light_name);

  IPAddress myIP = WiFi.localIP();
  Serial.print("IP: ");
  Serial.println(myIP);

  if (!light_state[0])
  {
    // Show that we are connected
    analogWrite(pins[0], 100);
    delay(500);
    analogWrite(pins[0], 0);
  }

  WiFi.macAddress(mac);

  pinMode(LED_BUILTIN, OUTPUT);     // Initialize the LED_BUILTIN pin as an output
  digitalWrite(LED_BUILTIN, HIGH);  // Turn the LED off by making the voltage HIGH

  httpUpdateServer.setup(&server); // start http server

  init_webserver();

  tc_init();

  server.begin();
} // end of setup

//********************************//

void loop()
{
  server.handleClient();
  lightEngine();

  if (tc_enabled == TIMING_CONTROL_ENABLED)
  {
    tc_update();
  }
}

//********************************//

void handleNotFound()
{
  String message = "File Not Found\n\n";
  message += "URI: ";
  message += server.uri();
  message += "\nMethod: ";
  message += (server.method() == HTTP_GET) ? "GET" : "POST";
  message += "\nArguments: ";
  message += server.args();
  message += "\n";

  for (uint8_t i = 0; i < server.args(); i++)
  {
    message += " " + server.argName(i) + ": " + server.arg(i) + "\n";
  }
  server.send(404, "text/plain", message);
}

//********************************//

void init_webserver()
{

#ifndef DISABLE_WEB_CONTROL
  server.on("/state", HTTP_PUT, []()
  { // HTTP PUT request used to set a new light state
    DynamicJsonDocument root(1024);
    DeserializationError error = deserializeJson(root, server.arg("plain"));

    if (error)
    {
      server.send(404, "text/plain", "FAIL. " + server.arg("plain"));
    } else {

      for (JsonPair state : root.as<JsonObject>())
      {
        const char* key = state.key().c_str();
        int light = atoi(key) - 1;
        JsonObject values = state.value();
        int transitiontime = 4;

        uint8_t tmp = EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS);
        if (values.containsKey("on"))
        {
          if (values["on"])
          {
            light_state[light] = true;
            if (tmp == LAST_STATE_STARTUP_LIGHT_LAST_STATE &&
                EEPROM.read(EEPROM_LAST_STATE_ADDRESS + light) == LIGHT_STATE_OFF)
            {
              EEPROM.write(EEPROM_LAST_STATE_ADDRESS + light, LIGHT_STATE_ON);
            }
          } else {
            light_state[light] = false;
            if (tmp == LAST_STATE_STARTUP_LIGHT_LAST_STATE &&
                EEPROM.read(EEPROM_LAST_STATE_ADDRESS + light) == LIGHT_STATE_ON)
            {
              EEPROM.write(EEPROM_LAST_STATE_ADDRESS + light, LIGHT_STATE_OFF);
            }
          }
        }

        if (values.containsKey("bri"))
        {
          bri[light] = values["bri"];
        }

        if (values.containsKey("bri_inc"))
        {
          bri[light] += (int) values["bri_inc"];
          if (bri[light] > 255) bri[light] = 255;
          else if (bri[light] < 1) bri[light] = 1;
        }

        if (values.containsKey("transitiontime"))
        {
          transitiontime = values["transitiontime"];
        }
        process_lightdata(light, transitiontime);
      }
      String output;
      serializeJson(root, output);
      server.send(200, "text/plain", output);
    }
  });

  server.on("/state", HTTP_GET, []()
  { // HTTP GET request used to fetch current light state
    uint8_t light = server.arg("light").toInt() - 1;
    DynamicJsonDocument root(1024);
    root["on"] = light_state[light];
    root["bri"] = bri[light];
    String output;
    serializeJson(root, output);
    server.send(200, "text/plain", output);
  });

  server.on("/detect", []()
  { // HTTP GET request used to discover the light type
    char macString[32] = {0};
    sprintf(macString, "%02X:%02X:%02X:%02X:%02X:%02X", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
    DynamicJsonDocument root(1024);
    root["name"] = light_name;
    root["lights"] = LIGHTS_COUNT;
    root["protocol"] = "native_multi";
    root["modelid"] = "LWB010";
    root["type"] = "dimmable_light";
    root["mac"] = String(macString);
    root["version"] = LIGHT_VERSION;
    String output;
    serializeJson(root, output);
    server.send(200, "text/plain", output);
  });

#endif // DISABLE_WEB_CONTROL

  server.on("/", []()
  {

#ifndef DISABLE_WEB_CONTROL
    static float transitiontime = 4.0;

    if (server.hasArg("transition"))
    {
      transitiontime = server.arg("transition").toFloat();
    }

    // startup behavior switch handling
    if (server.hasArg("startup"))
    {
      int startup = server.arg("startup").toInt();
      if (EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS) != startup)
      {
        EEPROM.write(EEPROM_LAST_STATE_STARTUP_ADDRESS, startup);

        for (uint8_t i = 0; i < LIGHTS_COUNT; i++)
        {
          uint8_t tmp = (light_state[i] == true ? LIGHT_STATE_ON : LIGHT_STATE_OFF);
          if (EEPROM.read(EEPROM_LAST_STATE_ADDRESS + i) != tmp)
          {
            EEPROM.write(EEPROM_LAST_STATE_ADDRESS + i, tmp);
          }
        }

        EEPROM.commit();
        Serial.print("Startup behavior set to "); Serial.println(EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS));
      }
    }
#endif // DISABLE_WEB_CONTROL

    // timing controller switch handling
    if (server.hasArg("tc"))
    {
      if (server.arg("tc") == "true")
      {
        if (tc_enabled == TIMING_CONTROL_DISABLED)
        {
          if (EEPROM.read(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS) != TIMING_CONTROL_ENABLED)
          {
            tc_enabled = TIMING_CONTROL_ENABLED;
            EEPROM.write(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS, TIMING_CONTROL_ENABLED);
            EEPROM.commit();
            Serial.print("Timing control = "); Serial.println(EEPROM.read(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS));
          }
        }

      } else { // tc is set to false or something else

        if (tc_enabled == TIMING_CONTROL_ENABLED)
        {
          tc_enabled = TIMING_CONTROL_DISABLED;
          if (EEPROM.read(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS) != TIMING_CONTROL_DISABLED)
          {
            EEPROM.write(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS, TIMING_CONTROL_DISABLED);
            EEPROM.commit();
            Serial.print("Timing control = "); Serial.println(EEPROM.read(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS));
          }
        }
      }
    }

#ifndef DISABLE_WEB_CONTROL

    // scene switch handling
    if (server.hasArg("scene"))
    {
      scene = server.arg("scene").toInt();
      if (EEPROM.read(EEPROM_SCENE_ADDRESS) != scene)
      {
        EEPROM.write(EEPROM_SCENE_ADDRESS, scene);
        EEPROM.commit();
        Serial.print("Scene set to "); Serial.println(EEPROM.read(EEPROM_SCENE_ADDRESS));
      }

    }

    if (server.hasArg("dip"))
    {
      uint8_t tmp = EEPROM.read(EEPROM_DYNAMIC_IP_ADDRESS);
      uint8_t tmp2 = (server.arg("dip") == "true" ? 1 : 0);
      if (tmp != tmp2)
      {
        EEPROM.write(EEPROM_DYNAMIC_IP_ADDRESS, tmp2);
        EEPROM.commit();
        Serial.print("Set dynamic IP to "); Serial.println(EEPROM.read(EEPROM_DYNAMIC_IP_ADDRESS));
      }
    }

    // process the received data for every light
    for (int light = 0; light < LIGHTS_COUNT; light++)
    {
      
      if (server.hasArg("bri" + (String)light))
      {
        bri[light] = (int)server.arg("bri" + (String)light).toInt();
        Serial.print("Brightness set to "); Serial.println(bri[light]);

      }
      
      if (server.hasArg("on" + (String)light))
      {
        uint8_t tmp = EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS);
        if (server.arg("on" + (String)light) == "true" && light_state[light] == false)
        {
          light_state[light] = true;
          if (tmp == 0 && EEPROM.read(EEPROM_LAST_STATE_ADDRESS + light) == 0)
          {
            EEPROM.write(EEPROM_LAST_STATE_ADDRESS + light, LIGHT_STATE_ON);
          }
          Serial.print("Light "); Serial.print(light); Serial.print(" state set to "); Serial.println(light_state[light]);

        } else if (server.arg("on" + (String)light) == "false"  && light_state[light] == true)
        {
          light_state[light] = false;
          if (tmp == 0 && EEPROM.read(EEPROM_LAST_STATE_ADDRESS + light) == 1)
          {
            EEPROM.write(EEPROM_LAST_STATE_ADDRESS + light, LIGHT_STATE_OFF);
          }
          Serial.print("Light "); Serial.print(light); Serial.print(" state set to "); Serial.println(light_state[light]);
        }

        EEPROM.commit();

      }

      // start alerting for every light
      if (server.hasArg("alert"))
      {
        if (light_state[light])
        {
          current_bri[light] = 0;
        } else {
          current_bri[light] = 255;
        }

      }

      // set the light step level
      if (light_state[light])
      {
        step_level[light] = ((float)bri[light] - current_bri[light]) / transitiontime;

      } else {
        step_level[light] = current_bri[light] / transitiontime;
      }
    }

#endif // DISABLE_WEB_CONTROL

    if (server.hasArg("resettc"))
    { // reqrite the tc config and reboot
      tc_write_default();
      ESP.reset();
    }

    if (server.hasArg("reset"))
    {
      ESP.reset();
    }

    // Generate HTML page
    String http_content = "<!doctype html>";
    http_content += "<html>";
    http_content += "<head>";
    http_content += "<meta charset=\"utf-8\">";
    http_content += "<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">";
    http_content += "<meta http-equiv=\"refresh\" content=\"15\">"; // Reload the page every 15 seconds automatically
    http_content += "<title>Light Setup</title>";
    http_content += "<link rel=\"stylesheet\" href=\"https://unpkg.com/purecss@0.6.2/build/pure-min.css\">";
    http_content += "</head>";
    http_content += "<body>";
    http_content += "<fieldset>";
    http_content += "<h3>" + (String)light_name + "</h3>";

    http_content += "<div class=\"pure-controls\">";
    http_content += "<span class=\"pure-form-message\"><a href=\"/?alert=1\">alert</a> &nbsp; <a href=\"/?reset=1\">reset</a> &nbsp; <a href=\"/?resettc\">reset timing control data</a> &nbsp; <a href=\"/update\">update</a></span>";
    http_content += "<label for=\"cb\" class=\"pure-checkbox\">";
    http_content += "</label>";
    http_content += "</div>";

    http_content += "<form class=\"pure-form pure-form-aligned\" action=\"/\" method=\"post\">";

#ifndef DISABLE_WEB_CONTROL
    http_content += "<br>";
    // Light control
    for (uint8 light_num = 0; light_num < LIGHTS_COUNT; light_num++)
    {
      http_content += "<h4>Light " + (String)(light_num+1) + "</h4>";
      http_content += "<div class=\"pure-control-group\">";
      http_content += "<label for=\"power\"><strong>Power</strong></label>";
      http_content += "<a class=\"pure-button"; if ( light_state[light_num]) http_content += " pure-button-primary"; http_content += "\" href=\"/?on" + (String)light_num + "=true\">ON</a>";
      http_content += "<a class=\"pure-button"; if (!light_state[light_num]) http_content += " pure-button-primary"; http_content += "\" href=\"/?on" + (String)light_num + "=false\">OFF</a>";
      http_content += "</div>";

      http_content += "<div class=\"pure-control-group\">";
      http_content += "<label for=\"bri\"" + (String)light_num + ">Bri</label>";
      http_content += "<input id=\"bri" + (String)light_num + "\" name=\"bri" + (String)light_num + "\" type=\"range\" min=\"0\" max=\"255\" value=\"" + (String)bri[light_num] + "\">";
      http_content += "<label id=\"bri" + (String)light_num + "_val\" name=\"bri" + (String)light_num + "\">" + (String)(int)(bri[light_num] * 100.0 / 255.0) + "</label>%";
      http_content += "<script>";
      http_content += "var slider" + (String)light_num + " = document.getElementById(\"bri" + (String)light_num + "\");";
      http_content += "var output" + (String)light_num + " = document.getElementById(\"bri" + (String)light_num + "\_val\");";
      http_content += "output" + (String)light_num + ".innerHTML = (Math.round((slider" + (String)light_num + ".value * 100.0 / 255.0) * 100) / 100).toFixed(2);";
      http_content += "slider" + (String)light_num + ".oninput = function() {";
      http_content += "output" + (String)light_num + ".innerHTML = (Math.round((this.value * 100.0 / 255.0) * 100) / 100).toFixed(2);";
      http_content += "}";
      http_content += "</script>";
      http_content += "</div>";
    }

    // timer data processing, startup state and scene for all of the lights
    http_content += "<br>";
    http_content += "<h3>Config</h3>";
    http_content += "<div class=\"pure-control-group\">";
    http_content += "<label for=\"startup\"><strong>Startup</strong></label>";
    http_content += "<select onchange=\"this.form.submit()\" id=\"startup\" name=\"startup\">";
    int ls_val = EEPROM.read(EEPROM_LAST_STATE_STARTUP_ADDRESS);
    http_content += "<option "; if (ls_val == LAST_STATE_STARTUP_LIGHT_LAST_STATE) http_content += "selected=\"selected\""; http_content += " value=\"0\">Last state</option>";
    http_content += "<option "; if (ls_val == LAST_STATE_STARTUP_LIGHT_ON_STATE)   http_content += "selected=\"selected\""; http_content += " value=\"1\">On</option>";
    http_content += "<option "; if (ls_val == LAST_STATE_STARTUP_LIGHT_OFF_STATE)  http_content += "selected=\"selected\""; http_content += " value=\"2\">Off</option>";
    http_content += "</select>";
    http_content += "</div>";

    http_content += "<div class=\"pure-control-group\">";
    http_content += "<label for=\"scene\"><strong>Scene</strong></label>";
    http_content += "<select onchange = \"this.form.submit()\" id=\"scene\" name=\"scene\">";
    int sc_val = EEPROM.read(EEPROM_SCENE_ADDRESS);
    http_content += "<option "; if (sc_val == SCENE_RELEAX)  http_content += "selected=\"selected\""; http_content += " value=\"0\">Relax</option>";
    http_content += "<option "; if (sc_val == SCENE_BRIGHT)  http_content += "selected=\"selected\""; http_content += " value=\"1\">Bright</option>";
    http_content += "<option "; if (sc_val == SCENE_NIGHTLY) http_content += "selected=\"selected\""; http_content += " value=\"2\">Night</option>";
    http_content += "</select>";
    http_content += "</div>";

    http_content += "<div class=\"pure-control-group\">";
    http_content += "<label for=\"power\"><strong>Timing control</strong></label>";
    int tc_val = EEPROM.read(EEPROM_TIMING_CONTROL_ENABLED_ADDRESS);
    http_content += "<a class=\"pure-button"; if (tc_val == TIMING_CONTROL_ENABLED)  http_content += "  pure-button-primary"; http_content += "\" href=\"/?tc=true\">ON</a>";
    http_content += "<a class=\"pure-button"; if (tc_val == TIMING_CONTROL_DISABLED) http_content += "  pure-button-primary"; http_content += "\" href=\"/?tc=false\">OFF</a>";
    http_content += "</div>";
    http_content += "<br>";

    http_content += "<div class=\"pure-control-group\">";
    http_content += "<label for=\"transition\">Transition time (s)</label>";
    http_content += "<input id=\"transition\" name=\"transition\" type=\"text\" placeholder=\"10\" value=\"" + (String)transitiontime + "\">";
    http_content += "</div>";

    // Wifi settings
    http_content += "<br>";
    http_content += "<h3>Wifi</h3>";
    http_content += "<div class=\"pure-control-group\">";
    http_content += "<label for=\"ip\">SSID</label>";
    http_content += "<input id=\"ssid\" name=\"ssid\" type=\"text\" value=\"" + WiFi.SSID() + "\">";
    http_content += "</div>";
    http_content += "<div class=\"pure-control-group\">";
    http_content += "<label for=\"wpw\">Passphrase</label>";
    http_content += "<input id=\"wpw\" name=\"wpw\" type=\"text\" placeholder=\"1234password\">";
    http_content += "</div>";

    // Network settings
    uint8_t dip = EEPROM.read(EEPROM_DYNAMIC_IP_ADDRESS);
    http_content += "<br>";
    http_content += "<h3>Network</h3>";
    http_content += "<div class=\"pure-control-group\">";
    http_content += "<label for=\"dip\"><strong>Dynamic-IP</strong></label>";
    http_content += "<a class=\"pure-button"; if ( dip) http_content += " pure-button-primary"; http_content += "\" href=\"/?dip=true\">ON</a>";
    http_content += "<a class=\"pure-button"; if (!dip) http_content += " pure-button-primary"; http_content += "\" href=\"/?dip=false\">OFF</a>";
    http_content += "</div>";

    if (dip == 0)
    {
      http_content += "<div class=\"pure-control-group\">";
      http_content += "<label for=\"ip\">IP</label>";
      http_content += "<input id=\"ip\" name=\"ip\" type=\"text\" value=\"" + WiFi.localIP().toString() + "\">";
      http_content += "</div>";
      http_content += "<div class=\"pure-control-group\">";
      http_content += "<label for=\"gwip\">Gateway IP</label>";
      http_content += "<input id=\"gwip\" name=\"gwip\" type=\"text\" value=\"" + WiFi.gatewayIP().toString() + "\">";
      http_content += "</div>";
      http_content += "<div class=\"pure-control-group\">";
      http_content += "<label for=\"ip\">Netmask</label>";
      http_content += "<input id=\"netmask\" name=\"netmas\" type=\"text\" value=\"" + WiFi.subnetMask().toString() + "\">";
      http_content += "</div>";
    }

    http_content += "<div class=\"pure-controls\">";
    http_content += "<button type=\"submit\" class=\"pure-button pure-button-primary\">Save</button>";
    http_content += "</div>";

#endif // DISABLE_WEB_CONTROL

    http_content += "</fieldset>";
    http_content += "</form>";
    http_content += "</body>";
    http_content += "</html>";

    server.send(200, "text/html", http_content);

  });

  server.on("/reset", []()
  { // trigger manual reset
    server.send(200, "text/html", "reset");
    delay(1000);
    ESP.restart();
  });

  server.onNotFound(handleNotFound);
}