/*
 * Copyright 2015-2020 the original author or authors.
 *
 * All rights reserved. This program and the accompanying materials are
 * made available under the terms of the Eclipse Public License v2.0 which
 * accompanies this distribution and is available at
 *
 * https://www.eclipse.org/legal/epl-v20.html
 */

package org.junit.jupiter.engine.descriptor;

import java.net.URI;

import org.junit.platform.commons.util.Preconditions;
import org.junit.platform.commons.util.ReflectionUtils;
import org.junit.platform.engine.discovery.DiscoverySelectors;
import org.junit.platform.engine.discovery.MethodSelector;
import org.junit.platform.engine.support.descriptor.MethodSource;

Jupiter internal support for creating MethodSource from URI. 
See Also:
MethodSource
MethodSelector
Since:
5.5/**
 * Jupiter internal support for creating {@link MethodSource} from {@link URI}.
 *
 * @since 5.5
 * @see MethodSource
 * @see MethodSelector
 */
class MethodSourceSupport {

	static final String METHOD_SCHEME = "method";

	
Create a new MethodSource from the supplied URI. 
The supplied URI should be of the form method:<FQMN> where FQMN is the fully qualified method name. See DiscoverySelectors.selectMethod(String) for the supported formats. 
The scheme-specific part component of the URI will be used as fully qualified class name. The fragment component of the URI will be used to retrieve the method name and method parameter types. 
Params:
uri – the URI for the method; never null
See Also:
METHOD_SCHEME
DiscoverySelectors.selectMethod(String)
Returns:
a new MethodSource; never null
Since:
5.5/**
	 * Create a new {@code MethodSource} from the supplied {@link URI}.
	 *
	 * <p>The supplied {@link URI} should be of the form {@code method:<FQMN>}
	 * where FQMN is the fully qualified method name. See
	 * {@link DiscoverySelectors#selectMethod(String)} for the supported formats.
	 *
	 * <p></p>The {@link URI#getSchemeSpecificPart() scheme-specific part}
	 * component of the {@code URI} will be used as fully qualified class name.
	 * The {@linkplain URI#getFragment() fragment} component of the {@code URI}
	 * will be used to retrieve the method name and method parameter types.
	 *
	 * @param uri the {@code URI} for the method; never {@code null}
	 * @return a new {@code MethodSource}; never {@code null}
	 * @since 5.5
	 * @see #METHOD_SCHEME
	 * @see DiscoverySelectors#selectMethod(String)
	 */
	static MethodSource from(URI uri) {
		Preconditions.notNull(uri, "URI must not be null");
		Preconditions.condition(METHOD_SCHEME.equals(uri.getScheme()),
			() -> "URI [" + uri + "] must have [" + METHOD_SCHEME + "] scheme");
		String schemeSpecificPart = Preconditions.notNull(uri.getSchemeSpecificPart(),
			() -> "Invalid method URI (scheme-specific part must not be null). Please consult the Javadoc of "
					+ DiscoverySelectors.class.getName()
					+ "#selectMethod(String) for details on the supported formats.");
		String fragment = Preconditions.notNull(uri.getFragment(),
			() -> "Invalid method URI (fragment must not be null). Please consult the Javadoc of "
					+ DiscoverySelectors.class.getName()
					+ "#selectMethod(String) for details on the supported formats.");

		String fullyQualifiedMethodName = schemeSpecificPart + "#" + fragment;
		String[] methodSpec = ReflectionUtils.parseFullyQualifiedMethodName(fullyQualifiedMethodName);
		return MethodSource.from(methodSpec[0], methodSpec[1], methodSpec[2]);
	}
}