#!/usr/bin/env python
# coding: utf-8

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import json
import copy
from ipyleaflet import Map, GeoJSON, Layer


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m = Map(center=[53.88, 27.45], zoom=3, name="Base map")
m


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# geojson layer with hover handler
with open("./europe_110.geo.json", "r") as f:
    data = json.load(f)

for feature in data["features"]:
    feature["properties"]["style"] = {
        "color": "grey",
        "weight": 1,
        "fillColor": "grey",
        "fillOpacity": 0.2,
    }

selected_set = set()
selected_layer = None


def convert_selected_set_to_geojson(selected_set):
    geojson = {"type": "FeatureCollection", "features": []}
    geojson["features"] = [
        feature
        for feature in data["features"]
        if feature["properties"]["iso_a3"] in selected_set
    ]
    for feature in data["features"]:
        feature["properties"]["style"] = {
            "color": "yellow",
            "weight": 2,
            "fillColor": "grey",
            "fillOpacity": 0.2,
        }
    return geojson


def selected_onclick_handler(event=None, id=None, properties=None, **args):
    global selected_layer
    if properties is None:
        return
    cid = properties["iso_a3"]
    selected_set.remove(cid)
    if selected_layer is not None:
        m.remove_layer(selected_layer)
    selected_layer = GeoJSON(
        data=convert_selected_set_to_geojson(selected_set),
        name="Selected EU Countries",
        hover_style={"fillColor": "yellow"},
    )
    selected_layer.on_click(selected_onclick_handler)
    m.add(selected_layer)


def geojson_onclick_handler(event=None, id=None, properties=None, **args):
    global selected_layer
    if properties is None:
        return
    cid = properties["iso_a3"]
    selected_set.add(cid)
    if selected_layer is not None:
        m.remove_layer(selected_layer)
    selected_layer = GeoJSON(
        data=convert_selected_set_to_geojson(selected_set),
        name="Selected EU Countries",
        hover_style={"fillColor": "yellow"},
    )
    selected_layer.on_click(selected_onclick_handler)
    m.add(selected_layer)


geojson_layer = GeoJSON(
    data=data, name="EU Countries", hover_style={"fillColor": "red"}
)
geojson_layer.on_click(geojson_onclick_handler)
m.add(geojson_layer)


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