Copyright (c) 2000, 2013 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2013 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package org.eclipse.debug.internal.core;

import java.util.Map;
import java.util.Map.Entry;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.Status;
import org.eclipse.core.variables.IDynamicVariable;
import org.eclipse.core.variables.IDynamicVariableResolver;
import org.eclipse.debug.core.DebugPlugin;
import org.eclipse.osgi.service.environment.Constants;

Resolves the value of environment variables.
/**
 * Resolves the value of environment variables.
 */
public class EnvironmentVariableResolver implements IDynamicVariableResolver {

	@Override
	public String resolveValue(IDynamicVariable variable, String argument) throws CoreException {
		if (argument == null) {
			throw new CoreException(new Status(IStatus.ERROR, DebugPlugin.getUniqueIdentifier(), IStatus.ERROR, DebugCoreMessages.EnvironmentVariableResolver_0, null));
		}
		Map<String, String> map = DebugPlugin.getDefault().getLaunchManager().getNativeEnvironmentCasePreserved();
		String value = map.get(argument);
		if (value == null && Platform.getOS().equals(Constants.OS_WIN32)) {
			// On Win32, env variables are case insensitive, so we search the map
			// for matches manually.
			for (Entry<String, String> entry : map.entrySet()) {
				String key = entry.getKey();
				if (key.equalsIgnoreCase(argument)) {
					return entry.getValue();
				}
			}
		}
		return value;
	}

}