/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you 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 groovy.grape

import org.apache.ivy.Ivy
import org.apache.ivy.core.cache.ResolutionCacheManager
import org.apache.ivy.core.event.IvyListener
import org.apache.ivy.core.event.download.PrepareDownloadEvent
import org.apache.ivy.core.event.resolve.StartResolveEvent
import org.apache.ivy.core.module.descriptor.Configuration
import org.apache.ivy.core.module.descriptor.DefaultDependencyArtifactDescriptor
import org.apache.ivy.core.module.descriptor.DefaultDependencyDescriptor
import org.apache.ivy.core.module.descriptor.DefaultExcludeRule
import org.apache.ivy.core.module.descriptor.DefaultModuleDescriptor
import org.apache.ivy.core.module.id.ArtifactId
import org.apache.ivy.core.module.id.ModuleId
import org.apache.ivy.core.module.id.ModuleRevisionId
import org.apache.ivy.core.report.ArtifactDownloadReport
import org.apache.ivy.core.report.ResolveReport
import org.apache.ivy.core.resolve.ResolveOptions
import org.apache.ivy.core.settings.IvySettings
import org.apache.ivy.plugins.matcher.ExactPatternMatcher
import org.apache.ivy.plugins.matcher.PatternMatcher
import org.apache.ivy.plugins.resolver.ChainResolver
import org.apache.ivy.plugins.resolver.IBiblioResolver
import org.apache.ivy.util.DefaultMessageLogger
import org.apache.ivy.util.Message
import org.codehaus.groovy.reflection.CachedClass
import org.codehaus.groovy.reflection.ClassInfo
import org.codehaus.groovy.reflection.ReflectionUtils
import org.codehaus.groovy.runtime.metaclass.MetaClassRegistryImpl

import javax.xml.parsers.DocumentBuilderFactory
import java.util.jar.JarFile
import java.util.regex.Pattern
import java.util.zip.ZipEntry
import java.util.zip.ZipException
import java.util.zip.ZipFile

/**
 * Implementation supporting {@code @Grape} and {@code @Grab} annotations based on Ivy.
 */
class GrapeIvy implements GrapeEngine {

    static final int DEFAULT_DEPTH = 3

    private final exclusiveGrabArgs = [
            ['group', 'groupId', 'organisation', 'organization', 'org'],
            ['module', 'artifactId', 'artifact'],
            ['version', 'revision', 'rev'],
            ['conf', 'scope', 'configuration'],
        ].inject([:], {m, g -> g.each {a -> m[a] = (g - a) as Set};  m})

    boolean enableGrapes
    Ivy ivyInstance
    Set<String> resolvedDependencies
    Set<String> downloadedArtifacts
    // weak hash map so we don't leak loaders directly
    Map<ClassLoader, Set<IvyGrabRecord>> loadedDeps = new WeakHashMap<ClassLoader, Set<IvyGrabRecord>>()
    // set that stores the IvyGrabRecord(s) for all the dependencies in each grab() call
    Set<IvyGrabRecord> grabRecordsForCurrDependencies = new LinkedHashSet<IvyGrabRecord>()
    // we keep the settings so that addResolver can add to the resolver chain
    IvySettings settings

    public GrapeIvy() {
        // if we are already initialized, quit
        if (enableGrapes) return

        // start ivy
        Message.defaultLogger = new DefaultMessageLogger(System.getProperty("ivy.message.logger.level", "-1") as int)
        settings = new IvySettings()

        // configure settings
        def grapeConfig = getLocalGrapeConfig()
        if (!grapeConfig.exists()) {
            grapeConfig = GrapeIvy.getResource("defaultGrapeConfig.xml")
        }
        try {
            settings.load(grapeConfig) // exploit multi-methods for convenience
        } catch (java.text.ParseException ex) {
            def configLocation = grapeConfig instanceof File ? grapeConfig.canonicalPath : grapeConfig.toString()
            System.err.println "Local Ivy config file '$configLocation' appears corrupt - ignoring it and using default config instead\nError was: " + ex.message
            grapeConfig = GrapeIvy.getResource("defaultGrapeConfig.xml")
            settings.load(grapeConfig)
        }

        // set up the cache dirs
        settings.defaultCache = getGrapeCacheDir()

        settings.setVariable("ivy.default.configuration.m2compatible", "true")
        ivyInstance = Ivy.newInstance(settings)
        resolvedDependencies = []
        downloadedArtifacts = []

        //TODO add grab to the DGM??

        enableGrapes = true
    }

    public File getGroovyRoot() {
        String root = System.getProperty("groovy.root")
        def groovyRoot
        if (root == null) {
            groovyRoot = new File(System.getProperty("user.home"), ".groovy")
        } else {
            groovyRoot = new File(root)
        }
        try {
            groovyRoot = groovyRoot.canonicalFile
        } catch (IOException e) {
            // skip canonicalization then, it may not exist yet
        }
        return groovyRoot
    }

    public File getLocalGrapeConfig() {
        String grapeConfig = System.getProperty("grape.config")
        if(grapeConfig) {
            return new File(grapeConfig)
        }
        return new File(getGrapeDir(), 'grapeConfig.xml')
    }

    public File getGrapeDir() {
        String root = System.getProperty("grape.root")
        if(root == null) {
            return getGroovyRoot()
        }
        File grapeRoot = new File(root)
        try {
            grapeRoot = grapeRoot.canonicalFile
        } catch (IOException e) {
            // skip canonicalization then, it may not exist yet
        }
        return grapeRoot
    }

    public File getGrapeCacheDir() {
        File cache =  new File(getGrapeDir(), 'grapes')
        if (!cache.exists()) {
            cache.mkdirs()
        } else if (!cache.isDirectory()) {
            throw new RuntimeException("The grape cache dir $cache is not a directory")
        }
        return cache
    }

    public def chooseClassLoader(Map args) {
        def loader = args.classLoader
        if (!isValidTargetClassLoader(loader)) {
            loader = (args.refObject?.class
                        ?:ReflectionUtils.getCallingClass(args.calleeDepth?:1)
                      )?.classLoader
            while (loader && !isValidTargetClassLoader(loader)) {
                loader = loader.parent
            }
            //if (!isValidTargetClassLoader(loader)) {
            //    loader = Thread.currentThread().contextClassLoader
            //}
            //if (!isValidTargetClassLoader(loader)) {
            //    loader = GrapeIvy.class.classLoader
            //}
            if (!isValidTargetClassLoader(loader)) {
                throw new RuntimeException("No suitable ClassLoader found for grab")
            }
        }
        return loader
    }

    private boolean isValidTargetClassLoader(loader) {
        return isValidTargetClassLoaderClass(loader?.class)
    }

    private boolean isValidTargetClassLoaderClass(Class loaderClass) {
        return (loaderClass != null) &&
            (
             (loaderClass.name == 'groovy.lang.GroovyClassLoader') ||
             (loaderClass.name == 'org.codehaus.groovy.tools.RootLoader') ||
             isValidTargetClassLoaderClass(loaderClass.superclass)
            )
    }

    public IvyGrabRecord createGrabRecord(Map deps) {
        // parse the actual dependency arguments
        String module =  deps.module ?: deps.artifactId ?: deps.artifact
        if (!module) {
            throw new RuntimeException('grab requires at least a module: or artifactId: or artifact: argument')
        }

        String groupId = deps.group ?: deps.groupId ?: deps.organisation ?: deps.organization ?: deps.org ?: ''
        String ext = deps.ext ?: deps.type ?: ''
        String type = deps.type ?: ''

        //TODO accept ranges and decode them?  except '1.0.0'..<'2.0.0' won't work in groovy
        String version = deps.version ?: deps.revision ?: deps.rev ?: '*'
        if ('*' == version) version = 'latest.default'

        ModuleRevisionId mrid = ModuleRevisionId.newInstance(groupId, module, version)

        boolean force      = deps.containsKey('force')      ? deps.force      : true
        boolean changing   = deps.containsKey('changing')   ? deps.changing   : false
        boolean transitive = deps.containsKey('transitive') ? deps.transitive : true
        def conf = deps.conf ?: deps.scope ?: deps.configuration ?: ['default']
        if (conf instanceof String) {
            if (conf.startsWith("[") && conf.endsWith("]")) conf = conf[1..-2]
            conf = conf.split(",").toList()
        }
        def classifier = deps.classifier ?: null

        return new IvyGrabRecord(mrid:mrid, conf:conf, changing:changing, transitive:transitive, force:force, classifier:classifier, ext:ext, type:type)
    }

    public grab(String endorsedModule) {
        return grab(group:'groovy.endorsed', module:endorsedModule, version:GroovySystem.version)
    }

    public grab(Map args) {
        args.calleeDepth = args.calleeDepth?:DEFAULT_DEPTH + 1
        return grab(args, args)
    }

    public grab(Map args, Map... dependencies) {
        ClassLoader loader = null
        grabRecordsForCurrDependencies.clear()

        try {
            // identify the target classloader early, so we fail before checking repositories
            loader = chooseClassLoader(
                classLoader:args.remove('classLoader'),
                refObject:args.remove('refObject'),
                calleeDepth:args.calleeDepth?:DEFAULT_DEPTH,
            )

            // check for non-fail null.
            // If we were in fail mode we would have already thrown an exception
            if (!loader) return

            def uris = resolve(loader, args, dependencies)
            for (URI uri in uris) {
                loader.addURL(uri.toURL())
            }
            for (URI uri in uris) {
                //TODO check artifact type, jar vs library, etc
                File file = new File(uri)
                processCategoryMethods(loader, file)
                processOtherServices(loader, file)
            }
        } catch (Exception e) {
            // clean-up the state first
            Set<IvyGrabRecord> grabRecordsForCurrLoader = getLoadedDepsForLoader(loader)
            grabRecordsForCurrLoader.removeAll(grabRecordsForCurrDependencies)
            grabRecordsForCurrDependencies.clear()

            if (args.noExceptions) {
                return e
            }
            throw e
        }
        return null
    }

    private processCategoryMethods(ClassLoader loader, File file) {
        // register extension methods if jar
        if (file.name.toLowerCase().endsWith(".jar")) {
            def mcRegistry = GroovySystem.metaClassRegistry
            if (mcRegistry instanceof MetaClassRegistryImpl) {
                try {
                    JarFile jar = new JarFile(file)
                    def entry = jar.getEntry(MetaClassRegistryImpl.MODULE_META_INF_FILE)
                    if (entry) {
                        Properties props = new Properties()
                        props.load(jar.getInputStream(entry))
                        Map<CachedClass, List<MetaMethod>> metaMethods = new HashMap<CachedClass, List<MetaMethod>>()
                        mcRegistry.registerExtensionModuleFromProperties(props, loader, metaMethods)
                        // add old methods to the map
                        metaMethods.each { CachedClass c, List<MetaMethod> methods ->
                            // GROOVY-5543: if a module was loaded using grab, there are chances that subclasses
                            // have their own ClassInfo, and we must change them as well!
                            Set<CachedClass> classesToBeUpdated = [c]
                            ClassInfo.onAllClassInfo { ClassInfo info ->
                                if (c.theClass.isAssignableFrom(info.cachedClass.theClass)) {
                                    classesToBeUpdated << info.cachedClass
                                }
                            }
                            classesToBeUpdated*.addNewMopMethods(methods)
                        }
                    }
                }
                catch(ZipException zipException) {
                    throw new RuntimeException("Grape could not load jar '$file'", zipException)
                }
            }
        }
    }

    void processOtherServices(ClassLoader loader, File f) {
        try {
            ZipFile zf = new ZipFile(f)
            ZipEntry serializedCategoryMethods = zf.getEntry("META-INF/services/org.codehaus.groovy.runtime.SerializedCategoryMethods")
            if (serializedCategoryMethods != null) {
                processSerializedCategoryMethods(zf.getInputStream(serializedCategoryMethods))
            }
            ZipEntry pluginRunners = zf.getEntry("META-INF/services/org.codehaus.groovy.plugins.Runners")
            if (pluginRunners != null) {
                processRunners(zf.getInputStream(pluginRunners), f.getName(), loader)
            }
        } catch(ZipException ignore) {
            // ignore files we can't process, e.g. non-jar/zip artifacts
            // TODO log a warning
        }
    }

    void processSerializedCategoryMethods(InputStream is) {
        is.text.readLines().each {
            println it.trim() // TODO implement this or delete it
        }
    }

    void processRunners(InputStream is, String name, ClassLoader loader) {
        is.text.readLines()*.trim().findAll{ !it.isEmpty() && it[0] != '#' }.each {
            try {
                GroovySystem.RUNNER_REGISTRY[name] = loader.loadClass(it).newInstance()
            } catch (Exception ex) {
                throw new IllegalStateException("Error registering runner class '" + it + "'", ex)
            }
        }
    }

    public ResolveReport getDependencies(Map args, IvyGrabRecord... grabRecords) {
        ResolutionCacheManager cacheManager = ivyInstance.resolutionCacheManager

        def millis = System.currentTimeMillis()
        def md = new DefaultModuleDescriptor(ModuleRevisionId
                .newInstance("caller", "all-caller", "working" + millis.toString()[-2..-1]), "integration", null, true)
        md.addConfiguration(new Configuration('default'))
        md.setLastModified(millis)

        addExcludesIfNeeded(args, md)

        for (IvyGrabRecord grabRecord : grabRecords) {
            def conf = grabRecord.conf ?: ['*']
            DefaultDependencyDescriptor dd = md.dependencies.find {it.dependencyRevisionId.equals(grabRecord.mrid)}
            if (dd) {
                createAndAddDependencyArtifactDescriptor(dd, grabRecord, conf)
            } else {
                dd = new DefaultDependencyDescriptor(md, grabRecord.mrid, grabRecord.force,
                        grabRecord.changing, grabRecord.transitive)
                conf.each {dd.addDependencyConfiguration('default', it)}
                createAndAddDependencyArtifactDescriptor(dd, grabRecord, conf)
                md.addDependency(dd)
            }
        }

       // resolve grab and dependencies
        ResolveOptions resolveOptions = new ResolveOptions()\
            .setConfs(['default'] as String[])\
            .setOutputReport(false)\
            .setValidate(args.containsKey('validate') ? args.validate : false)

        ivyInstance.settings.defaultResolver = args.autoDownload ? 'downloadGrapes' : 'cachedGrapes'
        if (args.disableChecksums) {
            ivyInstance.settings.setVariable('ivy.checksums', '')
        }
        boolean reportDownloads = System.getProperty('groovy.grape.report.downloads', 'false') == 'true'
        if (reportDownloads) {
            ivyInstance.eventManager.addIvyListener([progress:{ ivyEvent -> switch(ivyEvent) {
                case StartResolveEvent:
                    ivyEvent.moduleDescriptor.dependencies.each { it ->
                        def name = it.toString()
                        if (!resolvedDependencies.contains(name)) {
                            resolvedDependencies << name
                            System.err.println "Resolving " + name
                        }
                    }
                    break
                case PrepareDownloadEvent:
                    ivyEvent.artifacts.each { it ->
                        def name = it.toString()
                        if (!downloadedArtifacts.contains(name)) {
                            downloadedArtifacts << name
                            System.err.println "Preparing to download artifact " + name
                        }
                    }
                    break
            } } ] as IvyListener)
        }

        ResolveReport report = null
        int attempt = 8 // max of 8 times
        while (true) {
            try {
                report = ivyInstance.resolve(md, resolveOptions)
                break
            } catch(IOException ioe) {
                if (attempt--) {
                    if (reportDownloads)
                        System.err.println "Grab Error: retrying..."
                    sleep attempt > 4 ? 350 : 1000
                    continue
                }
                throw new RuntimeException("Error grabbing grapes -- $ioe.message")
            }
        }

        if (report.hasError()) {
            throw new RuntimeException("Error grabbing Grapes -- $report.allProblemMessages")
        }
        if (report.downloadSize && reportDownloads) {
            System.err.println "Downloaded ${report.downloadSize >> 10} Kbytes in ${report.downloadTime}ms:\n  ${report.allArtifactsReports*.toString().join('\n  ')}"
        }
        md = report.moduleDescriptor

        if (!args.preserveFiles) {
            cacheManager.getResolvedIvyFileInCache(md.moduleRevisionId).delete()
            cacheManager.getResolvedIvyPropertiesInCache(md.moduleRevisionId).delete()
        }

        return report
    }

    private void createAndAddDependencyArtifactDescriptor(DefaultDependencyDescriptor dd, IvyGrabRecord grabRecord, List<String> conf) {
        // TODO: find out "unknown" reason and change comment below - also, confirm conf[0] check vs conf.contains('optional')
        if (conf[0]!="optional" || grabRecord.classifier) {  // for some unknown reason optional dependencies should not have an artifactDescriptor
            def dad = new DefaultDependencyArtifactDescriptor(dd,
                    grabRecord.mrid.name, grabRecord.type ?: 'jar', grabRecord.ext ?: 'jar', null, grabRecord.classifier ? [classifier: grabRecord.classifier] : null)
            conf.each { dad.addConfiguration(it) }
            dd.addDependencyArtifact('default', dad)
        }
    }

    public void uninstallArtifact(String group, String module, String rev) {
        // TODO consider transitive uninstall as an option
        Pattern ivyFilePattern = ~/ivy-(.*)\.xml/ //TODO get pattern from ivy conf
        grapeCacheDir.eachDir { File groupDir ->
            if (groupDir.name == group) groupDir.eachDir { File moduleDir ->
                if (moduleDir.name == module) moduleDir.eachFileMatch(ivyFilePattern) { File ivyFile ->
                    def m = ivyFilePattern.matcher(ivyFile.name)
                    if (m.matches() && m.group(1) == rev) {
                        // TODO handle other types? e.g. 'dlls'
                        def jardir = new File(moduleDir, 'jars')
                        if (!jardir.exists()) return
                        def dbf = DocumentBuilderFactory.newInstance()
                        def db = dbf.newDocumentBuilder()
                        def root = db.parse(ivyFile).documentElement
                        def publis = root.getElementsByTagName('publications')
                        for (int i=0; i<publis.length;i++) {
                            def artifacts = publis.item(i).getElementsByTagName('artifact')
                            for (int j=0; j<artifacts.length; j++) {
                                def artifact = artifacts.item(j)
                                def attrs = artifact.attributes
                                def name = attrs.getNamedItem('name').getTextContent() + "-$rev"
                                def classifier = attrs.getNamedItemNS("m", "classifier")?.getTextContent()
                                if (classifier) name += "-$classifier"
                                name += ".${attrs.getNamedItem('ext').getTextContent()}"
                                def jarfile = new File(jardir, name)
                                if (jarfile.exists()) {
                                    println "Deleting ${jarfile.name}"
                                    jarfile.delete()
                                }
                            }
                        }
                        ivyFile.delete()
                    }
                }
            }
        }
    }

    private addExcludesIfNeeded(Map args, DefaultModuleDescriptor md) {
        if (!args.containsKey('excludes')) return
        args.excludes.each{ map ->
            def excludeRule = new DefaultExcludeRule(new ArtifactId(
                    new ModuleId(map.group, map.module), PatternMatcher.ANY_EXPRESSION,
                    PatternMatcher.ANY_EXPRESSION,
                    PatternMatcher.ANY_EXPRESSION),
                    ExactPatternMatcher.INSTANCE, null)
            excludeRule.addConfiguration('default')
            md.addExcludeRule(excludeRule)
        }
    }

    public Map<String, Map<String, List<String>>> enumerateGrapes() {
        Map<String, Map<String, List<String>>> bunches = [:]
        Pattern ivyFilePattern = ~/ivy-(.*)\.xml/ //TODO get pattern from ivy conf
        grapeCacheDir.eachDir {File groupDir ->
            Map<String, List<String>> grapes = [:]
            bunches[groupDir.name] = grapes
            groupDir.eachDir { File moduleDir ->
                def versions = []
                moduleDir.eachFileMatch(ivyFilePattern) {File ivyFile ->
                    def m = ivyFilePattern.matcher(ivyFile.name)
                    if (m.matches()) versions += m.group(1)
                }
                grapes[moduleDir.name] = versions
            }
        }
        return bunches
    }

    public URI[] resolve(Map args, Map ... dependencies) {
        resolve(args, null, dependencies)
    }

    public URI[] resolve(Map args, List depsInfo, Map ... dependencies) {
        // identify the target classloader early, so we fail before checking repositories
        def loader = chooseClassLoader(
                classLoader: args.remove('classLoader'),
                refObject: args.remove('refObject'),
                calleeDepth: args.calleeDepth ?: DEFAULT_DEPTH,
        )

        // check for non-fail null.
        // If we were in fail mode we would have already thrown an exception
        if (!loader) return

        resolve(loader, args, depsInfo, dependencies)
    }

    URI [] resolve(ClassLoader loader, Map args, Map... dependencies) {
        return resolve(loader, args, null, dependencies)
    }

    URI [] resolve(ClassLoader loader, Map args, List depsInfo, Map... dependencies) {
        // check for mutually exclusive arguments
        Set keys = args.keySet()
        keys.each {a ->
            Set badArgs = exclusiveGrabArgs[a]
            if (badArgs && !badArgs.disjoint(keys)) {
                throw new RuntimeException("Mutually exclusive arguments passed into grab: ${keys.intersect(badArgs) + a}")
            }
        }

        // check the kill switch
        if (!enableGrapes) { return }

        boolean populateDepsInfo = (depsInfo != null)

        Set<IvyGrabRecord> localDeps = getLoadedDepsForLoader(loader)

        dependencies.each {
            IvyGrabRecord igr = createGrabRecord(it)
            grabRecordsForCurrDependencies.add(igr)
            localDeps.add(igr)
        }
        // the call to reverse ensures that the newest additions are in
        // front causing existing dependencies to come last and thus
        // claiming higher priority.  Thus when module versions clash we
        // err on the side of using the class already loaded into the
        // classloader rather than adding another jar of the same module
        // with a different version
        ResolveReport report = null
        try {
            report = getDependencies(args, *localDeps.asList().reverse())
        } catch (Exception e) {
            // clean-up the state first
            localDeps.removeAll(grabRecordsForCurrDependencies)
            grabRecordsForCurrDependencies.clear()
            throw e
        }

        List<URI> results = []
        for (ArtifactDownloadReport adl in report.allArtifactsReports) {
            //TODO check artifact type, jar vs library, etc
            if (adl.localFile) {
                results += adl.localFile.toURI()
            }
        }

        if (populateDepsInfo) {
            def deps = report.dependencies
            deps.each { depNode ->
                def id = depNode.id
                depsInfo << ['group' : id.organisation, 'module' : id.name, 'revision' : id.revision]
            }
        }

        return results as URI[]
    }

    private Set<IvyGrabRecord> getLoadedDepsForLoader(ClassLoader loader) {
        Set<IvyGrabRecord> localDeps = loadedDeps.get(loader)
        if (localDeps == null) {
            // use a linked set to preserve initial insertion order
            localDeps = new LinkedHashSet<IvyGrabRecord>()
            loadedDeps.put(loader, localDeps)
        }
        return localDeps
    }

    public Map[] listDependencies (ClassLoader classLoader) {
        if (loadedDeps.containsKey(classLoader)) {
            List<Map> results = []
            loadedDeps[classLoader].each { IvyGrabRecord grabbed ->
                def dep =  [
                    group : grabbed.mrid.organisation,
                    module : grabbed.mrid.name,
                    version : grabbed.mrid.revision
                ]
                if (grabbed.conf != ['default']) {
                    dep.conf = grabbed.conf
                }
                if (grabbed.changing) {
                    dep.changing = grabbed.changing
                }
                if (!grabbed.transitive) {
                    dep.transitive = grabbed.transitive
                }
                if (!grabbed.force) {
                    dep.force = grabbed.force
                }
                if (grabbed.classifier) {
                    dep.classifier = grabbed.classifier
                }
                if (grabbed.ext) {
                    dep.ext = grabbed.ext
                }
                if (grabbed.type) {
                    dep.type = grabbed.type
                }
                results << dep
            }
            return results
        }
        return null
    }

    public void addResolver(Map<String, Object> args) {
        ChainResolver chainResolver = settings.getResolver("downloadGrapes")

        IBiblioResolver resolver = new IBiblioResolver(name: args.name, root:args.root,
              m2compatible:(args.m2Compatible ?: true), settings:settings)

        chainResolver.add(resolver)

        ivyInstance = Ivy.newInstance(settings)
        resolvedDependencies = []
        downloadedArtifacts = []
    }
}

class IvyGrabRecord {
    ModuleRevisionId mrid
    List<String> conf
    boolean changing
    boolean transitive
    boolean force
    String classifier
    String ext
    String type

    public int hashCode() {
        return (mrid.hashCode() ^ conf.hashCode()
            ^ (changing ? 0xaaaaaaaa : 0x55555555)
            ^ (transitive ? 0xbbbbbbbb : 0x66666666)
            ^ (force ? 0xcccccccc: 0x77777777)
            ^ (classifier ? classifier.hashCode() : 0)
            ^ (ext ? ext.hashCode() : 0)
            ^ (type ? type.hashCode() : 0))
    }

    public boolean equals(Object o) {
        return ((o.class == IvyGrabRecord)
            && (changing == o.changing)
            && (transitive == o.transitive)
            && (force== o.force)
            && (mrid == o.mrid)
            && (conf == o.conf)
            && (classifier == o.classifier)
            && (ext == o.ext)
            && (type == o.type))
    }

}
