PermissionUtils

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.provider.Settings;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.ActivityCompat;
import android.view.View;




public class PermissionUtils {
    public static final int REQUEST_MEDIA_PIC = 101;
    public static final String TAG = "PermissionUtils";
    private static final int REQUEST_CONTACTS = 1;
    @Nullable
    public static PermissionUtils instance = null;
    public OnPermissionChanged listener;
    private Activity activity;
    private View layout;

    private PermissionUtils() {

    }

    @Nullable
    public static PermissionUtils getInstance() {
        if (null == instance) {
            instance = new PermissionUtils();
        }
        return instance;
    }

    public static boolean isGranted(@NonNull int[] grantResults) {
        // At least one result must be checked.
        if (grantResults.length < 1) {
            return false;
        }

        // Verify that each required permission has been granted, otherwise return false.
        for (int result : grantResults) {
            if (result != PackageManager.PERMISSION_GRANTED) {
                return false;
            }
        }
        return true;
    }

    /**
     * To check permission granted before requesting it with user.
     *
     * @param context
     * @param permission
     * @return
     */
    public boolean hasPermission(@NonNull Context context, @NonNull String permission) {
        return ActivityCompat.checkSelfPermission(context, permission)
                == PackageManager.PERMISSION_GRANTED;

    }

    public boolean hasAllPermissions(@NonNull Activity activity, @NonNull String[] permissions) {
        if (permissions.length < 1) {
            return false;
        }
        for (String result : permissions) {
            if (ActivityCompat.checkSelfPermission(activity, result)
                    != PackageManager.PERMISSION_GRANTED) {
                return false;
            }

        }

        return true;
    }

    /**
     * To check if Permission granted after requesting it with user.
     *
     * @param grantResults
     * @return
     */
    public boolean isPermissionGranted(@NonNull int[] grantResults) {
        if (grantResults.length < 1) {
            return false;
        }
        for (int result : grantResults) {
            if (result != PackageManager.PERMISSION_GRANTED) {
                return false;
            }
        }
        return true;
    }

    /**
     * Callback received when a permissions request has been completed.
     */
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
                                           @NonNull int[] grantResults) {
        if (isGranted(grantResults)) {
            listener.onGranted(requestCode);
        } else {
            if (isShowShowPermissionRationale(activity, permissions)) {
                //showStoragePermissionRationale();
                listener.onRejected(requestCode);

            } else {
                final GenericDialogFragment.Builder builder = new GenericDialogFragment.Builder(activity);
                builder.setCancelOnTouchOutside(true).setCancelable(true)
                        .setTitle("Permission").setMessage("We require these permissions to take image of your expense. We will redirect you to settings>App>Permission").setPositiveBtnText("OK")
                        .setPositiveBtnClickListener(new GenericDialogFragment.OnPositiveBtnClickListener() {
                            @Override
                            public void onClick(GenericDialogFragment dialog) {
                                builder.dissmiss();
                                Intent intent = new Intent();
                                intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                                Uri uri = Uri.fromParts("package", activity.getPackageName(), null);
                                intent.setData(uri);
                                activity.startActivity(intent);
                            }
                        }).show();


            }
        }


    }

    private void requestPermission(@NonNull Activity activity, @NonNull String[] permission, int requestCode) {
        ActivityCompat.requestPermissions(activity,
                permission,
                requestCode);
    }

    public boolean isShowShowPermissionRationale(@NonNull Activity activity, @NonNull String[] permissions) {
        if (permissions.length < 1) {
            return false;
        }
        for (String result : permissions) {
            if (ActivityCompat.shouldShowRequestPermissionRationale(activity,
                    result)) {
                return true;
            }
        }
        return false;

    }

    public void showRationale(@NonNull final Activity activity, View layout, String message, @NonNull final String[] permissions, final int requestCode) {
        final GenericDialogFragment.Builder builder = new GenericDialogFragment.Builder(activity);
        builder.setCancelOnTouchOutside(true).setCancelable(true)
                .setTitle("Permission").setMessage("We require these permissions to take image of your expense").setPositiveBtnText("OK")
                .setPositiveBtnClickListener(new GenericDialogFragment.OnPositiveBtnClickListener() {
                    @Override
                    public void onClick(GenericDialogFragment dialog) {
                        builder.dissmiss();
                        ActivityCompat.requestPermissions(activity,
                                permissions,
                                requestCode);
                    }
                }).show();

    }

    public void requestPermission(@NonNull Activity activity, @NonNull String[] permissions, View layout, String message, int requestCode, @NonNull OnPermissionChanged listener) {
        this.listener = listener;
        this.activity = activity;
        this.layout = layout;
        if (permissions.length < 1) {
            return;
        }

        if (!hasAllPermissions(activity, permissions)) {
            if (isShowShowPermissionRationale(activity, permissions)) {
                showRationale(activity, layout, message, permissions, requestCode);
            } else {
                requestPermission(activity, permissions, requestCode);
            }
        } else {
            listener.hasAllPermission(requestCode);
        }
    }

    public interface OnPermissionChanged {
        void onGranted(int requestCode);

        void onRejected(int requestCode);

        void hasAllPermission(int requestCode);
    }
}