Spherical/app/src/main/java/de/trac/spherical/MainActivity.java

package de.trac.spherical;

import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.TextView;
import android.widget.Toast;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import de.trac.spherical.parser.SphereParser;

public class MainActivity extends AppCompatActivity {

    public static final String TAG = "Spherical";

    public static final String MIME_PHOTO_SPHERE = "application/vnd.google.panorama360+jpg";
    public static final String MIME_IMAGE = "image/*";

    private TextView text;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //TODO: Remove later
        text = (TextView) findViewById(R.id.hello_world);

        Intent intent = getIntent();
        switch (intent.getAction()) {
            //Image was sent into the app
            case Intent.ACTION_SEND:
                handleSentImageIntent(intent);
                break;

            //App was launched via launcher icon
            //TODO: Remove later together with launcher intent filter
            default:
                Toast.makeText(this, R.string.prompt_share_image, Toast.LENGTH_LONG).show();
        }
    }

    /**
     * Distinguish type of sent image. Images with the MIME type of a photosphere will be directly
     * displayed, while images with MIME type image/* are being manually tested using {@link SphereParser}.
     * @param intent incoming intent.
     */
    private void handleSentImageIntent(Intent intent) {
        String type = intent.getType();
        if (type != null) {

            Uri imageUri = intent.getParcelableExtra(Intent.EXTRA_STREAM);
            if (imageUri == null) {
                Toast.makeText(this, R.string.file_not_found, Toast.LENGTH_SHORT).show();
                return;
            }

            switch (type) {
                case MIME_PHOTO_SPHERE:
                    displayPhotoSphere(imageUri);
                    break;

                case MIME_IMAGE:
                    displayMaybePhotoSphere(imageUri);
                    break;
            }

        } else {
            Toast.makeText(this, "TODO: Figure out what to do :D", Toast.LENGTH_SHORT).show();
        }
    }

    /**
     * Check, whether the sent photo is a photo sphere and display either a sphere, or a plain image.
     * @param uri
     */
    private void displayMaybePhotoSphere(Uri uri) {
        try {
            InputStream inputStream = getContentResolver().openInputStream(uri);
            String xml = SphereParser.getXMLContent(inputStream);

            boolean sphere = true; //TODO: parser.

            if (sphere) {
                displayPhotoSphere(uri);
            } else {
                displayFlatImage(uri);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * Display a photo sphere.
     * @param uri
     */
    private void displayPhotoSphere(Uri uri) {
        try {
            InputStream inputStream = getContentResolver().openInputStream(uri);
            String xml = SphereParser.getXMLContent(inputStream);

            if (xml != null) {
                text.setText(xml);
            } else {
                text.setText("null");
            }

        } catch (FileNotFoundException e) {
            Log.e(TAG, "File not found.", e);
            Toast.makeText(this, R.string.file_not_found, Toast.LENGTH_SHORT).show();
        } catch (IOException e) {
            Log.e(TAG, "IOException: ", e);
            Toast.makeText(this, R.string.ioerror, Toast.LENGTH_SHORT).show();
        }
    }

    /**
     * Display a flat image.
     * @param uri
     */
    private void displayFlatImage(Uri uri) {

    }
}