// Copyright (C) 2008 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.google.gerrit.client;

import com.google.gerrit.client.openid.OpenIdLoginPanel;
import com.google.gerrit.client.rpc.Common;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.Widget;
import com.google.gwtexpui.user.client.AutoCenterDialogBox;

/**
 * Prompts the user to sign in to their account.
 * <p>
 * This dialog performs the login within an iframe, allowing normal HTML based
 * login pages to be used, including those which aren't served from the same
 * server as Gerrit. This is important to permit an OpenID provider or some
 * other web based single-sign-on system to be used for authentication.
 * <p>
 * Post login the iframe content is expected to execute the JavaScript snippet:
 * 
 * <pre>
 * $callback(account);
 * </pre>
 * 
 * where <code>$callback</code> is the parameter in the initial request and
 * <code>account</code> is either <code>!= null</code> (the user is now signed
 * in) or <code>null</code> (the sign in was aborted/canceled before it
 * completed).
 */
public class SignInDialog extends AutoCenterDialogBox {
  public static enum Mode {
    SIGN_IN, LINK_IDENTIY;
  }

  private Widget panel;

  /**
   * Create a new dialog to handle user sign in.
   */
  public SignInDialog() {
    this(Mode.SIGN_IN);
  }

  /**
   * Create a new dialog to handle user sign in.
   * 
   * @param signInMode type of mode the login will perform.
   */
  public SignInDialog(final Mode signInMode) {
    super(/* auto hide */true, /* modal */true);

    switch (Common.getGerritConfig().getLoginType()) {
      case OPENID:
        panel = new OpenIdLoginPanel(signInMode);
        break;

      default: {
        final FlowPanel fp = new FlowPanel();
        fp.add(new Label(Gerrit.C.loginTypeUnsupported()));
        panel = fp;
        break;
      }
    }
    add(panel);

    switch (signInMode) {
      case LINK_IDENTIY:
        setText(Gerrit.C.linkIdentityDialogTitle());
        break;
      default:
        setText(Gerrit.C.signInDialogTitle());
        break;
    }
  }

  @Override
  public void show() {
    super.show();
    if (panel instanceof OpenIdLoginPanel) {
      ((OpenIdLoginPanel) panel).setFocus(true);
    }
  }
}