app.py

import sys
import os
import leafmap
from helpers.grid import *
from helpers.functional import *
from leafmap.toolbar import change_basemap
from IPython.display import display
import ipywidgets
import solara

instructions_top = '''
![image/png](https://cdn-uploads.huggingface.co/production/uploads/6304c06eeb6d777a838eab63/BJKsLwX0GG4W3-gdf40TJ.png)
# Dataset Viewer

This app provides a way of exploring samples present in the MajorTOM-Core dataset.
It contains nearly every piece of Earth capture by ESA Sentinel-2 satellite.

### Instructions
To find a sample, navigate on the map to a place of interest. Click `Find Sample` to find a dataset sample that contains the central pixel of your current view.
'''

instructions_bottom = '''
<details><summary><strong>🏝 Couldn't find a sample? See this figure of global coverage:</strong></summary>
    <img src='https://cdn-uploads.huggingface.co/production/uploads/6304c06eeb6d777a838eab63/2KTarfsM0a1dNYEbXriUH.png' />
</details>
'''

image_data = solara.reactive(Image.new('RGB',(1068,1068)))
center = solara.reactive((20, 0))
gridcell = solara.reactive('')
zoom= solara.reactive(4)
s2_level = solara.reactive('L2A')

@solara.component
def Page():
    with solara.Column():

        with solara.Card(margin=10):
            solara.Markdown(instructions_top)
            solara.Button(label="Website",
                  icon_name="mdi-map-legend",
                  attributes={"href": 'https://www.huggingface.co/Major-TOM', "target": "_blank"},
                  text=True,
                  outlined=True)
    
            solara.Button(label="arXiv Paper",
                          icon_name="mdi-script-text",
                          attributes={"href": 'https://www.arxiv.org/abs/2402.12095', "target": "_blank"},
                          text=True,
                          outlined=True)
            solara.Markdown(instructions_bottom)
        
        def update_image():
            ret = map_to_image(m, return_centre=True, return_gridcell=True, l2a=(s2_level.value=='L2A'))
            if ret is not None:
                image_data.value, center.value, gridcell.value = ret
                zoom.value=12
            else:
                image_data.value = Image.new('RGB',(1068,1068))
                center.value = (20,0)
                zoom.value = 4

        def update_level(level):
            s2_level.value = level
            update_image()
        
        with solara.Card(margin=10):
            with solara.ColumnsResponsive(default=12, small=12, medium=6, large=6, xlarge=6):
                with solara.Column(align='center'):
                    m = leafmap.Map(
                        height=560,
                        width=560,
                        layout=ipywidgets.Layout(max_width='60vw', max_height='80vh'),
                        zoom=zoom.value,
                        center=center.value,
                        draw_control=False,
                        measure_control=False,
                        fullscreen_control=False,
                        toolbar_control=False,
                        attribution_control=True,
                    )
                    display(m)
                    button = solara.Button("Find Sample", on_click=update_image, height='80px')                    
                    solara.Select(label="Processing Level", value=s2_level, values=['L2A','L1C'], on_value=update_level)
                with solara.Column(align='center'):
                    output = solara.Image(image_data.value)
                    solara.Markdown('''        
                    |                     |      |
                    |--------------------:|:----:|
                    | Latitude, Longitude | {:.3f}, {:.3f} |
                    |       MajorTOM Grid | {} |
                    '''.format(center.value[0], center.value[1], gridcell.value))