weatherWebApp

var roi1 = ee.FeatureCollection("FAO/GAUL/2015/level1")
  .filter(ee.Filter.eq('ADM1_NAME', 'Tyumenskaya Oblast')); // Выберите геометрию Республики Алтай
var roi = roi1.geometry();
var panel = ui.Panel({
  layout: ui.Panel.Layout.flow('vertical'),
  style: {
    width: '300px',
    position: 'top-left'
  }
});
Map.setCenter(68.969, 58.736, 6);
panel.add(ui.Label('Weather Forecast for Tyumen Region'));

var dateSelector = ui.DateSlider({
  period: 1,
  start: '2023-08-01',
  end: '2023-09-30'
});
panel.add(dateSelector);

Map.add(panel);

// Глобальные переменные для хранения текущей легенды и слоя
var currentLegend = null;
var currentLayer = null;

function updateLegend(min, max, date) {
  // Удаляем старую легенду
  if (currentLegend) {
    Map.remove(currentLegend);
  }
  
  var legend = ui.Panel({
    style: {
      position: 'bottom-left',
      padding: '8px 15px'
    }
  });
  
  var legendTitle = ui.Label('Temperature (°C) for ' + date, {
    fontWeight: 'bold',
    fontSize: '18px',
    margin: '0 0 4px 0',
    padding: '0'
  });
  
  legend.add(legendTitle);
  
  var lon = ee.Image.pixelLonLat().select('latitude');
  var gradient = lon.multiply((max-min)/100.0).add(min);
  var legendImage = gradient.visualize({min: min, max: max, palette: ['blue', 'purple', 'cyan', 'green', 'yellow', 'red']});

  var panelLegend = ui.Panel({
    widgets: [ui.Label(min.toFixed(2)+'°C'), ui.Label(max.toFixed(2)+'°C')],
    style: {
      stretch: 'horizontal',
      textAlign: 'center',
      margin: '0px 8px'
    }
  });
  legend.add(panelLegend);
  
  Map.add(legend);
  currentLegend = legend; // Обновляем глобальную переменную
}

function generateForecast(date) {
  var forecast_date = ee.Date(date);
  
  var collection = ee.ImageCollection('NOAA/GFS0P25')
                  .filterDate(forecast_date, forecast_date.advance(1, 'day'));
  var firstImage = collection.first();
  
  var minTemperature = firstImage.reduceRegion({
    reducer: ee.Reducer.min(),
    geometry: roi,
    scale: 1000
  }).get('temperature_2m_above_ground');

  var maxTemperature = firstImage.reduceRegion({
    reducer: ee.Reducer.max(),
    geometry: roi,
    scale: 1000
  }).get('temperature_2m_above_ground');
  
  var tempViz = {
    min: minTemperature.getInfo(),
    max: maxTemperature.getInfo(),
    palette: ['blue', 'purple', 'cyan', 'green', 'yellow', 'red']
  };

  updateLegend(tempViz.min, tempViz.max, ee.Date(date).format('YYYY-MM-dd').getInfo());
  
  var resampledImage = firstImage.resample('bilinear');
  var clippedImage = resampledImage.clip(roi);
  
  // Удаляем старый слой перед добавлением нового
  if (currentLayer) {
    Map.remove(currentLayer);
  }

  var layerName = 'Temperature for ' + ee.Date(date).format('YYYY-MM-dd').getInfo();
currentLayer = Map.addLayer(clippedImage.select('temperature_2m_above_ground'), tempViz, layerName);
}

var generateButton = ui.Button({
  label: 'Создать прогноз',
  onClick: function() {
    var selectedDates = dateSelector.getValue();
    var selectedDate = selectedDates[0];
    generateForecast(selectedDate);
  }
});

panel.add(generateButton);

function exportData(date) {
  var forecast_date = ee.Date(date);
  
  var collection = ee.ImageCollection('NOAA/GFS0P25')
                  .filterDate(forecast_date, forecast_date.advance(1, 'day'));
  
  var hourlyData = collection.map(function(img) {
    var meanValues = img.select(['temperature_2m_above_ground', 'relative_humidity_2m_above_ground']).reduceRegion({
      reducer: ee.Reducer.mean(),
      geometry: roi,
      scale: 1000
    });

    var forecastTime = img.get('forecast_time');
    
    return ee.Feature(null, {
      'forecast_time': forecastTime,
      'mean_temperature': meanValues.get('temperature_2m_above_ground'),
      'mean_humidity': meanValues.get('relative_humidity_2m_above_ground')
    });
  });
  
  Export.table.toDrive({
    collection: hourlyData,
    description: 'hourly_mean_temperature_humidity_data_for_' + date,
    fileFormat: 'CSV'
  });
}

var exportButton = ui.Button({
  label: 'Export Data',
  onClick: function() {
    var selectedDates = dateSelector.getValue();
    var selectedDate = selectedDates[0];
    exportData(selectedDate);
  }
});
panel.add(exportButton);