/*
 * Geopaparazzi - Digital field mapping on Android based devices
 * Copyright (C) 2016  HydroloGIS (www.hydrologis.com)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package eu.geopaparazzi.library.mixare;

import java.io.File;
import java.util.List;

import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.net.Uri;
import eu.geopaparazzi.library.util.FileUtilities;
import eu.geopaparazzi.library.util.PointF3D;
import eu.geopaparazzi.library.core.ResourcesManager;

/**
 * Utilities for interaction with the Mixare project. 
 * 
 * <p>
 * A mixare json object looks like:
 * <pre>
 * {
 *     "id": "2827",
 *     "lat": "46.43893",
 *     "lng": "11.21706",
 *     "elevation": "1737",
 *     "title": "Penegal",
 *     "distance": "9.756",
 *     "has_detail_page": "1",
 *     "webpage": "http%3A%2F%2Fwww.suedtirolerland.it%2Fapi%2Fmap%2FgetMarkerTplM%2F%3Fmarker_id%3D2827%26project_id%3D15%26lang_id%3D9"
 * }
 * </pre>
 * 
 * <p>With everything optional but lat, lng, elevation and title.
 * 
 * @author Andrea Antonello (www.hydrologis.com)
 */
@SuppressWarnings("nls")
public class MixareHandler {

    /**
     * Show the points in the supplied region in Mixare.
     * 
     * @param context the {@link Context} to use.
     * @param points the {@link PointF3D} to display.
     * @throws Exception  if something goes wrong.
     */
    public static void runRegionOnMixare( Context context, List<PointF3D> points ) throws Exception {
        String mixareJson = generateMixareData(context, points);
        File applicationDir = ResourcesManager.getInstance(context).getApplicationSupporterDir();
        File mixarefile = new File(applicationDir, "mixare.json");
        FileUtilities.writefile(mixareJson, mixarefile);
        String mixareUri = "file://" + mixarefile.getAbsolutePath();

        Intent i = new Intent();
        i.setAction(Intent.ACTION_VIEW);
        i.setDataAndType(Uri.parse(mixareUri), "application/mixare-json");
        context.startActivity(i);
    }

    /**
     * Generate the json string needed by mixare.
     * 
     * <p>This is done via strign concatenation since at some point this 
     * could go directly to files in stream to avoid memory problems.
     *
     * @param context the {@link Context} to use.
     * @param points the {@link PointF3D} to display.
     * @throws Exception
     */
    private static String generateMixareData( Context context, List<PointF3D> points ) throws Exception {
        StringBuilder sb = new StringBuilder();

        int size = points.size();
        for( int i = 0; i < size; i++ ) {
            PointF3D p3d = points.get(i);
            String json = dataToString(i, p3d.y, p3d.x, p3d.getZ(), p3d.getDescription());
            if (i > 0) {
                sb.append(",");
            }
            sb.append(json);
        }

        String jsonString = sb.toString();

        StringBuilder finalSb = new StringBuilder();
        finalSb.append("{\n");
        finalSb.append("\"status\": \"OK\",\n");
        finalSb.append("\"num_results\":").append(size).append(",\n");
        finalSb.append("\"results\": [\n");
        finalSb.append(jsonString);
        finalSb.append("]\n");
        finalSb.append("}\n");
        return finalSb.toString();
    }



    private static String dataToString( int id, double lat, double lon, double elev, String title ) {
        StringBuilder sb = new StringBuilder();
        sb.append("{\n");
        sb.append("\"id\": \"").append(id).append("\",").append("\n");
        sb.append("\"lat\": \"").append(lat).append("\",").append("\n");
        sb.append("\"lng\": \"").append(lon).append("\",").append("\n");
        sb.append("\"elevation\": \"").append(elev).append("\",").append("\n");
        sb.append("\"title\": \"").append(title).append("\"").append("\n");
        sb.append("}\n");
        return sb.toString();
    }

    /**
     * Checks if Mixare is installed.
     * 
     * @param context the {@link Context} to use.
     * @return <code>true</code> if mixare is installed.
     */
    public static boolean isMixareInstalled( Context context ) {
        // We try to locate mixare on the phone
        try {
            PackageInfo pi = context.getPackageManager().getPackageInfo("org.mixare", 0);
            if (pi.versionCode >= 1) {
                return true;
            }
        } catch (PackageManager.NameNotFoundException ex) {
            ex.printStackTrace();
        }
        return false;
    }

    /**
     * Lanches an intent that guides to the mixare installation.
     * 
     * @param context the {@link Context} to use.
     */
    public static void installMixareFromMarket( Context context ) {
        Intent i = new Intent();
        i.setAction(Intent.ACTION_VIEW);
        i.setData(Uri.parse("market://search?q=pname:org.mixare"));
        context.startActivity(i);
    }
}