FilterStateModel.java

package org.openstreetmap.josm.plugins.rasterfilters.model;

import java.awt.Color;
import java.util.HashMap;
import java.util.Map;
import java.util.Map.Entry;

import javax.json.Json;
import javax.json.JsonObject;
import javax.json.JsonObjectBuilder;

import org.openstreetmap.josm.plugins.rasterfilters.values.BooleanValue;
import org.openstreetmap.josm.plugins.rasterfilters.values.ColorValue;
import org.openstreetmap.josm.plugins.rasterfilters.values.SelectValue;
import org.openstreetmap.josm.plugins.rasterfilters.values.SliderValue;
import org.openstreetmap.josm.plugins.rasterfilters.values.Value;

/**
 * Filter state's model which stores all parameters of
 * the filter according to its meta-information.
 * The usual values from meta-information are converted
 * into subtypes of the generic interface {@link Value}
 *
 * @author Nipel-Crumple
 */
public class FilterStateModel {

    private Map<String, Value<?>> params = new HashMap<>();
    private String filterClassName;

    public FilterStateModel() {

    }

    public Map<String, Value<?>> getParams() {
        return params;
    }

    public String getFilterClassName() {
        return filterClassName;
    }

    public void setFilterClassName(String filterClassName) {
        this.filterClassName = filterClassName;
    }

    public void addParams(JsonObject json) {

        String parameterName = json.getString("name");
        String valueType = json.getString("value_type");

        // setting up the beginning state of filter
        // according to its metainfo
        if (json.getString("type").equals("linear_slider")) {

            if (valueType.equals("float") || valueType.equals("double")) {

                double defaultValue = json.getJsonNumber("default")
                        .doubleValue();

                SliderValue<Double> value = new SliderValue<>(parameterName,
                        defaultValue);
                params.put(parameterName, value);

            } else if (valueType.equals("integer")) {

                int defaultValue = json.getJsonNumber("default").intValue();

                SliderValue<Integer> value = new SliderValue<>(parameterName,
                        defaultValue);
                params.put(parameterName, value);

            }

        } else if (json.getString("type").equals("checkbox")) {

            boolean defaultValue = json.getBoolean("default");

            BooleanValue value = new BooleanValue(parameterName, defaultValue);
            params.put(parameterName, value);

        } else if (json.getString("type").equals("select")) {

            String defaultValue = json.getString("default");

            SelectValue<String> value = new SelectValue<>(parameterName,
                    defaultValue);
            params.put(parameterName, value);

        } else if (json.getString("type").equals("colorpicker")) {

            JsonObject defaultColorJson = json.getJsonObject("default");
            int r = defaultColorJson.getInt("red");
            int g = defaultColorJson.getInt("green");
            int b = defaultColorJson.getInt("blue");

            Color defaultColor = new Color(r, g, b);

            ColorValue<Color> value = new ColorValue<>(parameterName,
                    defaultColor);
            params.put(parameterName, value);

        }
    }

    /**
     * Method generates json from the current filter's model state.
     *
     * @return encoded json which describes current filter's state
     */
    public JsonObject encodeJson() {

        JsonObjectBuilder jsonBuilder = Json.createObjectBuilder();

        for (Entry<String, Value<?>> entry : params.entrySet()) {

            Object value = entry.getValue().getValue();

            if (value instanceof String) {

                jsonBuilder.add(entry.getKey(),
                        Json.createObjectBuilder().add("value", (String) value)
                                .build());

            }

            if (value instanceof Boolean) {
                jsonBuilder.add(entry.getKey(),
                        Json.createObjectBuilder()
                                .add("value", (Boolean) value).build());
            }

            if (value instanceof Number) {

                if (value instanceof Double) {

                    jsonBuilder.add(entry.getKey(), Json.createObjectBuilder()
                            .add("value", (Double) value).build());

                } else if (value instanceof Integer) {

                    jsonBuilder.add(entry.getKey(), Json.createObjectBuilder()
                            .add("value", (Integer) value).build());

                }
            }

            if (value instanceof Color) {

                jsonBuilder.add(entry.getKey(),
                        Json.createObjectBuilder()
                                .add("value", Json.createObjectBuilder()
                                        .add("red", ((Color) value).getRed())
                                        .add("green", ((Color) value).getGreen())
                                        .add("blue", ((Color) value).getBlue())
                                        .build())
                                .build());

            }
        }

        return jsonBuilder.build();
    }
}