display_weather.yaml

# This is ESPHome configuration file. This goes to the esphome folder
# You need to provide your WiFi ssis/password and passwords for API and OTA (or put them in your esphome/secrets.yaml)
esphome:
  name: display_weather
  platform: ESP8266
  board: d1_mini_pro

wifi:
  ssid: !secret wifi_ssid
  password: !secret wifi_password
  fast_connect: true

api:
  password: !secret api_password

ota:
  password: !secret ota_password

logger:
  baud_rate: 0     # Disable UART logging (pins GPIO1/3 are used for Nextion communication)

uart:
  rx_pin: D1
  tx_pin: D2
  baud_rate: 115200

time:
  - platform: sntp
    id: sntp_time

sensor:
  - platform: homeassistant
    id: sun_elevation
    entity_id: sensor.sun_elevation
  - platform: homeassistant   # Inside temperature
    id: temperature_inside
    entity_id: sensor.temperature_inside
  - platform: homeassistant   # Outside temperature
    id: temperature_outside    
    entity_id: sensor.temperature_outside
  - platform: homeassistant   # Swimming pool
    id: temperature_pool
    entity_id: sensor.temperature_pool
  - platform: homeassistant   # Forecast minimal temperature
    id: today_min
    entity_id: sensor.today_min
  - platform: homeassistant   # Forecast maximal temperature
    id: today_max
    entity_id: sensor.today_max
  - platform: homeassistant   # Forecast precipitation
    id: today_rain
    entity_id: sensor.today_rain
  - platform: homeassistant   # Forecast icon
    id: today_icon
    entity_id: sensor.today_icon

binary_sensor:
  - platform: homeassistant
    id: somebody_home
    entity_id: binary_sensor.somebody_home

globals:
 - id: first_page             # First page of the display?
   type: bool
   restore_value: no
 - id: current_brightness             # Is display on?
   type: float
   restore_value: no
   initial_value: '-1.0'
   
display:
  - platform: nextion
    id: teplomer
    update_interval: 5s
    lambda: |-      
      // Turn display on when somebody is home. Only update when display on.
      float br;
      if (id(somebody_home).state) {   
        if (id(sun_elevation).state > 0) {
          // Full brightness during the day
          br=1.0;    
        } else {
          // 50 percent at night
          br=0.5;
        }
        // Swich first/second page on each update (every 5 seconds)
        if (id(first_page)) {
          it.goto_page("forecast");
          it.send_command_printf("%s.pic=%.0f", "weather",id(today_icon).state);
          it.set_component_text_printf("minmax","%.0f/%.0f",id(today_min).state,id(today_max).state);
          if (isnan(id(today_rain).state)) {
            it.set_component_text("rain","-");
          } else {
            it.set_component_text_printf("rain","%.0f",id(today_rain).state);
          }
          auto time = id(sntp_time).now();
          it.set_component_text_printf("hour","%02d",time.hour);
          it.set_component_text_printf("minute","%02d",time.minute);
        } else {
          it.goto_page("temperature");
          it.set_component_text_printf("inside","%2.1f",id(temperature_inside).state);
          it.set_component_text_printf("outside","%2.1f",id(temperature_outside).state);
          it.set_component_text_printf("pool","%2.1f",id(temperature_pool).state);
        }
        id(first_page) = !id(first_page);  // Switch page
      } else {
        // Turn off the display if nobody is home. 
        br=0.0;
      }
      
      // Change brightnes if it needs to be changed
      if (id(current_brightness)!=br) {  
        it.set_backlight_brightness(br);
        id(current_brightness)=br;
      }