import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Build;
import android.provider.Settings;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;

import com.afollestad.materialdialogs.MaterialDialog;

import java.util.HashMap;
import java.util.Map;

public class PermissionsManager {

    public static final int REQUEST_FOR_PERMISSON_READ_EXTRNAL_STORAGE = 101;
    public static final int REQUEST_FOR_PERMISSON_RECORD_AUDIO = 102;

    private final PermissionsRequester requester;
    private Map<Permission, PermissionCallback> callbacks = new HashMap<>();

    public PermissionsManager(PermissionsRequester requester) {
        this.requester = requester;
    }

    public void checkPermission(Permission permission, PermissionCallback listener) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            callbacks.put(permission, listener);
            if (ContextCompat.checkSelfPermission(requester.getActivity(), permission.getPermission()) != PackageManager.PERMISSION_GRANTED) {
                if (requester.shouldForShowRequestPermissionRationale(permission.getPermission())) {
                    showDefaultRationale(permission);
                } else {
                    requester.requestForPermissions(new String[]{permission.getPermission()}, permission.getRequestCode());
                }
            } else {
                listener.onPermissionGranted();
            }
        } else {
            listener.onPermissionGranted();
        }
    }

    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        Permission permission;
        PermissionCallback listener;
        switch (requestCode) {
            case REQUEST_FOR_PERMISSON_READ_EXTRNAL_STORAGE: {
                permission = new ReadExternalStoragePermission();
                listener = callbacks.get(permission);
            }
            break;
            case REQUEST_FOR_PERMISSON_RECORD_AUDIO: {
                permission = new RecordAudioPermission();
                listener = callbacks.get(permission);
            }
            break;
            default:
                return;
        }
        if (isPermissionGranted(grantResults)) {
            listener.onPermissionGranted();
        } else {
            if (!ActivityCompat.shouldShowRequestPermissionRationale(requester.getActivity(), permission.getPermission())) {
                listener.onNeverShowClicked();
            }
        }
    }

    public void openApplicationSettings() {
        Intent appSettingsIntent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:" + requester.getActivity().getPackageName()));
        requester.getActivity().startActivityForResult(appSettingsIntent, REQUEST_FOR_PERMISSON_READ_EXTRNAL_STORAGE);
    }

    private boolean isPermissionGranted(int[] grantResults) {
        boolean isPermissionGranted = true;
        if (grantResults.length <= 0)
            return false;
        for (int result : grantResults)
            if (result == PackageManager.PERMISSION_DENIED)
                isPermissionGranted = false;
        return isPermissionGranted;
    }

    private void showDefaultRationale(Permission permission) {
        MaterialDialog.Builder builder = new MaterialDialog.Builder(requester.getActivity());
        builder.title(R.string.dialog_title_permission_record_audio);
        builder.content(permission.getRationaleRes());
        builder.positiveText(R.string.dialog_button_ok);
        builder.onPositive((dialog, which) ->
                requester.requestForPermissions(new String[]{permission.getPermission()}, permission.getRequestCode()));
        builder.build().show();
    }
}