/*
 * Copyright 2011 Esri.
 *
 * 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.esri.gpt.control.webharvest.client.thredds;

import com.esri.gpt.framework.resource.api.SourceUri;
import com.esri.gpt.framework.resource.common.CommonPublishable;
import com.esri.gpt.framework.resource.common.UrlUri;
import com.esri.gpt.framework.util.Val;
import java.io.IOException;
import java.util.Date;

/**
 * THREDDS file.
 */
class TFile extends CommonPublishable {

  private UrlUri uri;
  private TProxy proxy;
  private TProxy.Content content;
  private IOException storedException;

  public TFile(TProxy proxy, String url) {
    this.proxy = proxy;
    this.uri = new UrlUri(url);
  }

  @Override
  public SourceUri getSourceUri() {
    return uri;
  }

  @Override
  public String getContent() throws IOException {
    // rethrow stored exception which occured during getUpdateDate()
    if (storedException != null) {
      throw storedException;
    }
    if (content == null) {
      content = proxy.readContent(getSourceUri().asString());
    }
    String metadata = "";
    if (content != null) {
      metadata = Val.chkStr(content.getText());
      content = null;
    }
    return metadata;
  }

  @Override
  public Date getUpdateDate() {
    try {
      if (content == null) {
        content = proxy.readContent(getSourceUri().asString());
      }
    } catch (IOException ex) {
      // store that exception here because getUpdateDate can not throw any exception by interface
      // instead getContent() would rethrow this exception
      storedException = ex;
    }
    return content != null ? content.getLastModifedDate() : null;
  }
}