/*
 * Copyright 2016-2019 Red Hat, Inc. and/or its affiliates
 * and other contributors as indicated by the @author tags.
 *
 * 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 org.jboss.galleon.runtime;

import java.io.BufferedReader;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.xml.stream.XMLStreamException;

import org.jboss.galleon.Constants;
import org.jboss.galleon.Errors;
import org.jboss.galleon.ProvisioningDescriptionException;
import org.jboss.galleon.ProvisioningException;
import org.jboss.galleon.UnsatisfiedPackageDependencyException;
import org.jboss.galleon.config.ConfigId;
import org.jboss.galleon.config.ConfigModel;
import org.jboss.galleon.config.FeatureGroup;
import org.jboss.galleon.layout.FeaturePackLayout;
import org.jboss.galleon.spec.ConfigLayerSpec;
import org.jboss.galleon.spec.FeaturePackSpec;
import org.jboss.galleon.spec.FeatureSpec;
import org.jboss.galleon.spec.PackageDependencySpec;
import org.jboss.galleon.type.ParameterTypeProvider;
import org.jboss.galleon.type.builtin.BuiltInParameterTypeProvider;
import org.jboss.galleon.universe.FeaturePackLocation.FPID;
import org.jboss.galleon.universe.FeaturePackLocation.ProducerSpec;
import org.jboss.galleon.util.LayoutUtils;
import org.jboss.galleon.util.CollectionUtils;
import org.jboss.galleon.xml.ConfigXmlParser;
import org.jboss.galleon.xml.FeatureGroupXmlParser;
import org.jboss.galleon.xml.FeatureSpecXmlParser;
import org.jboss.galleon.xml.PackageXmlParser;
import org.jboss.galleon.xml.XmlParsers;

/**
 *
 * @author Alexey Loubyansky
 */
public class FeaturePackRuntimeBuilder extends FeaturePackLayout {

    static final int VISIT                     = 0b001;
    static final int RESOLVE_LAYER             = 0b010;
    static final int RESOLVE_MODEL_ONLY_CONFIG = 0b100;

    final ProducerSpec producer;
    Map<String, ResolvedFeatureSpec> featureSpecs = null;
    private Map<String, FeatureGroup> fgSpecs = null;
    private Map<ConfigId, ConfigModel> configs = null;
    private Map<ConfigId, ConfigLayerSpec> layers = null;

    Map<String, PackageRuntime.Builder> pkgBuilders = Collections.emptyMap();
    List<String> pkgOrder = new ArrayList<>();

    private ParameterTypeProvider featureParamTypeProvider = BuiltInParameterTypeProvider.getInstance();

    private int flags;

    public FeaturePackRuntimeBuilder(FPID fpid, FeaturePackSpec spec, Path dir, int type) {
        super(fpid, dir, type);
        this.producer = fpid.getProducer();
        this.dir = dir;
        this.spec = spec;
    }

    boolean isFlagOn(int flag) {
        return (flags & flag) > 0;
    }

    boolean setFlag(int flag) {
        if((flags & flag) > 0) {
            return false;
        }
        flags ^= flag;
        return true;
    }

    int clearFlag(int flag) {
        if((flags & flag) > 0) {
            flags ^= flag;
        }
        return flags;
    }

    int getFlags() {
        return flags;
    }

    boolean resolvePackage(String pkgName, ProvisioningRuntimeBuilder rt, PackageRuntime.Builder parent, int type) throws ProvisioningException {
        PackageRuntime.Builder pkgBuilder = pkgBuilders.get(pkgName);
        if(pkgBuilder == null) {
            final Path pkgDir = LayoutUtils.getPackageDir(dir, pkgName, false);
            if (!Files.exists(pkgDir)) {
                return false;
            }
            final Path pkgXml = pkgDir.resolve(Constants.PACKAGE_XML);
            if (!Files.exists(pkgXml)) {
                throw new ProvisioningDescriptionException(Errors.pathDoesNotExist(pkgXml));
            }

            try (BufferedReader reader = Files.newBufferedReader(pkgXml)) {
                pkgBuilder = PackageRuntime.builder(this, PackageXmlParser.getInstance().parse(reader), pkgDir, ++rt.pkgsTotal);
            } catch (IOException | XMLStreamException e) {
                throw new ProvisioningException(Errors.parseXml(pkgXml), e);
            }
            if (!pkgBuilder.spec.getName().equals(pkgName)) {
                throw new ProvisioningDescriptionException("Feature-pack " + getFPID() + " package spec name "
                        + pkgBuilder.spec.getName() + " does not match the requested package name " + pkgName);
            }
            pkgBuilders = CollectionUtils.put(pkgBuilders, pkgName, pkgBuilder);
        }
        pkgBuilder.referencedAs(type);
        if(parent == null) {
            pkgBuilder.setFlag(PackageRuntime.ROOT);
            if(type == PackageDependencySpec.REQUIRED) {
                pkgBuilder.include();
            }
        } else if(!parent.isFlagOn(PackageRuntime.SCHEDULED)) {
            parent.addPackageDep(pkgBuilder, type, rt.includedPkgDeps);
        }
        if(!rt.addToPkgDepBranch(pkgBuilder)) {
            // to avoid stack overflow processing circular dependencies
            return true;
        }
        if(pkgBuilder.spec.hasPackageDeps()) {
            final FeaturePackRuntimeBuilder currentOrigin = rt.setOrigin(this);
            try {
                rt.processPackageDeps(pkgBuilder.spec, pkgBuilder);
            } catch(UnsatisfiedPackageDependencyException e) {
                throw new UnsatisfiedPackageDependencyException(getFPID(), pkgName, e);
            } catch(ProvisioningException e) {
                throw new ProvisioningException(Errors.resolvePackage(getFPID(), pkgName), e);
            } finally {
                rt.setOrigin(currentOrigin);
            }
        }
        return true;
    }

    FeatureGroup getFeatureGroupSpec(String name) throws ProvisioningException {
        if(fgSpecs != null) {
            final FeatureGroup fgSpec = fgSpecs.get(name);
            if(fgSpec != null) {
                return fgSpec;
            }
        }
        final Path specXml = dir.resolve(Constants.FEATURE_GROUPS).resolve(name + ".xml");
        if (!Files.exists(specXml)) {
            return null;
        }
        try (BufferedReader reader = Files.newBufferedReader(specXml)) {
            final FeatureGroup fgSpec = FeatureGroupXmlParser.getInstance().parse(reader);
            if(!fgSpec.getName().equals(name)) {
                throw new ProvisioningDescriptionException("Feature-pack " + getFPID() + " feature group " + fgSpec.getName() + " does not match the requested feature group name " + name);
            }
            if (fgSpecs == null) {
                fgSpecs = new HashMap<>();
            }
            fgSpecs.put(name, fgSpec);
            return fgSpec;
        } catch (Exception e) {
            throw new ProvisioningException(Errors.parseXml(specXml), e);
        }
    }

    ConfigModel getConfig(ConfigId configId) throws ProvisioningException {
        if(configs != null) {
            final ConfigModel config = configs.get(configId);
            if(config != null) {
                return config;
            }
        }
        final Path p = LayoutUtils.getConfigXml(dir, configId, false);
        if (!Files.exists(p)) {
            return null;
        }
        try (BufferedReader reader = Files.newBufferedReader(p)) {
            final ConfigModel config = ConfigXmlParser.getInstance().parse(reader);
            if (configs == null) {
                configs = new HashMap<>();
            }
            configs.put(config.getId(), config);
            return config;
        } catch (Exception e) {
            throw new ProvisioningException(Errors.parseXml(p), e);
        }
    }

    ConfigLayerSpec getConfigLayer(ConfigId configId) throws ProvisioningException {
        if(layers != null) {
            final ConfigLayerSpec layer = layers.get(configId);
            if(layer != null) {
                return layer;
            }
        }
        final Path p = LayoutUtils.getLayerSpecXml(dir, configId.getModel(), configId.getName(), false);
        if (!Files.exists(p)) {
            return null;
        }
        final ConfigLayerSpec layer = XmlParsers.parseConfigLayerSpec(p, configId.getModel());
        if (layers == null) {
            layers = new HashMap<>();
        }
        layers.put(configId, layer);
        return layer;
    }

    public ResolvedFeatureSpec getFeatureSpec(String name) throws ProvisioningException {
        if(featureSpecs != null) {
            final ResolvedFeatureSpec resolvedSpec = featureSpecs.get(name);
            if(resolvedSpec != null) {
                return resolvedSpec;
            }
        }
        final Path specXml = dir.resolve(Constants.FEATURES).resolve(name).resolve(Constants.SPEC_XML);
        if (!Files.exists(specXml)) {
            return null;
        }
        try (BufferedReader reader = Files.newBufferedReader(specXml)) {
            final FeatureSpec xmlSpec = FeatureSpecXmlParser.getInstance().parse(reader);
            if(!xmlSpec.getName().equals(name)) {
                throw new ProvisioningDescriptionException("Feature-pack " + getFPID() + " feature spec " + xmlSpec.getName() + " does not match the requested feature spec name " + name);
            }
            final ResolvedFeatureSpec resolvedSpec = new ResolvedFeatureSpec(new ResolvedSpecId(producer, xmlSpec.getName()),
                    featureParamTypeProvider, xmlSpec);
            if (featureSpecs == null) {
                featureSpecs = new HashMap<>();
            }
            featureSpecs.put(name, resolvedSpec);
            return resolvedSpec;
        } catch (Exception e) {
            throw new ProvisioningDescriptionException(Errors.parseXml(specXml), e);
        }
    }

    FeaturePackRuntime build(ProvisioningRuntimeBuilder rt) throws ProvisioningException {
        return new FeaturePackRuntime(this, rt);
    }
}