/*
 * Copyright 2011 the original author or authors.
 *
 * 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.gradle.api.plugins.quality;

import com.google.common.util.concurrent.Callables;
import groovy.lang.Closure;
import org.gradle.api.Action;
import org.gradle.api.artifacts.Configuration;
import org.gradle.api.artifacts.DependencySet;
import org.gradle.api.file.ConfigurableFileTree;
import org.gradle.api.file.FileCollection;
import org.gradle.api.internal.ConventionMapping;
import org.gradle.api.plugins.quality.internal.AbstractCodeQualityPlugin;
import org.gradle.api.reporting.SingleFileReport;
import org.gradle.api.resources.TextResource;
import org.gradle.api.tasks.SourceSet;

import java.io.File;
import java.util.Collection;
import java.util.concurrent.Callable;

/**
 * A plugin for the <a href="http://findbugs.sourceforge.net">FindBugs</a> byte code analyzer.
 *
 * <p>
 * Declares a <tt>findbugs</tt> configuration which needs to be configured with the FindBugs library to be used.
 * Additional plugins can be added to the <tt>findbugsPlugins</tt> configuration.
 *
 * <p>
 * For projects that have the Java (base) plugin applied, a {@link FindBugs} task is
 * created for each source set.
 *
 * @see FindBugs
 * @see FindBugsExtension
 */
public class FindBugsPlugin extends AbstractCodeQualityPlugin<FindBugs> {

    public static final String DEFAULT_FINDBUGS_VERSION = "3.0.1";
    private FindBugsExtension extension;

    @Override
    protected String getToolName() {
        return "FindBugs";
    }

    @Override
    protected Class<FindBugs> getTaskType() {
        return FindBugs.class;
    }

    @Override
    protected void beforeApply() {
        configureFindBugsConfigurations();
    }

    private void configureFindBugsConfigurations() {
        Configuration configuration = project.getConfigurations().create("findbugsPlugins");
        configuration.setVisible(false);
        configuration.setTransitive(true);
        configuration.setDescription("The FindBugs plugins to be used for this project.");
    }

    @Override
    protected CodeQualityExtension createExtension() {
        extension = project.getExtensions().create("findbugs", FindBugsExtension.class, project);
        extension.setToolVersion(DEFAULT_FINDBUGS_VERSION);
        return extension;
    }

    @Override
    protected void configureTaskDefaults(FindBugs task, String baseName) {
        task.setPluginClasspath(project.getConfigurations().getAt("findbugsPlugins"));
        Configuration configuration = project.getConfigurations().getAt("findbugs");
        configureDefaultDependencies(configuration);
        configureTaskConventionMapping(configuration, task);
        configureReportsConventionMapping(task, baseName);
    }

    private void configureDefaultDependencies(Configuration configuration) {
        configuration.defaultDependencies(new Action<DependencySet>() {
            @Override
            public void execute(DependencySet dependencies) {
                dependencies.add(project.getDependencies().create("com.google.code.findbugs:findbugs:" + extension.getToolVersion()));
            }
        });
    }

    private void configureTaskConventionMapping(Configuration configuration, FindBugs task) {
        ConventionMapping taskMapping = task.getConventionMapping();
        taskMapping.map("findbugsClasspath", Callables.returning(configuration));
        taskMapping.map("ignoreFailures", new Callable<Boolean>() {
            @Override
            public Boolean call() {
                return extension.isIgnoreFailures();
            }
        });
        taskMapping.map("effort", new Callable<String>() {
            @Override
            public String call() {
                return extension.getEffort();
            }
        });
        taskMapping.map("reportLevel", new Callable<String>() {
            @Override
            public String call() {
                return extension.getReportLevel();
            }
        });
        taskMapping.map("visitors", new Callable<Collection<String>>() {
            @Override
            public Collection<String> call() {
                return extension.getVisitors();
            }
        });
        taskMapping.map("omitVisitors", new Callable<Collection<String>>() {
            @Override
            public Collection<String> call() {
                return extension.getOmitVisitors();
            }
        });

        taskMapping.map("excludeFilterConfig", new Callable<TextResource>() {
            @Override
            public TextResource call() {
                return extension.getExcludeFilterConfig();
            }
        });
        taskMapping.map("includeFilterConfig", new Callable<TextResource>() {
            @Override
            public TextResource call() {
                return extension.getIncludeFilterConfig();
            }
        });
        taskMapping.map("excludeBugsFilterConfig", new Callable<TextResource>() {
            @Override
            public TextResource call() {
                return extension.getExcludeBugsFilterConfig();
            }
        });

        taskMapping.map("extraArgs", new Callable<Collection<String>>() {
            @Override
            public Collection<String> call() {
                return extension.getExtraArgs();
            }
        });
    }

    private void configureReportsConventionMapping(FindBugs task, final String baseName) {
        task.getReports().all(new Action<SingleFileReport>() {
            @Override
            public void execute(final SingleFileReport report) {
                ConventionMapping reportMapping = conventionMappingOf(report);
                reportMapping.map("enabled", new Callable<Boolean>() {
                    @Override
                    public Boolean call() {
                        return report.getName().equals("xml");
                    }
                });
                reportMapping.map("destination", new Callable<File>() {
                    @Override
                    public File call() {
                        return new File(extension.getReportsDir(), baseName + "." + report.getName());
                    }
                });
            }
        });
    }

    @Override
    protected void configureForSourceSet(final SourceSet sourceSet, FindBugs task) {
        task.setDescription("Run FindBugs analysis for " + sourceSet.getName() + " classes");
        task.setSource(sourceSet.getAllJava());
        ConventionMapping taskMapping = task.getConventionMapping();
        taskMapping.map("classes", new Callable<FileCollection>() {
            @Override
            public FileCollection call() {
                // the simple "classes = sourceSet.output" may lead to non-existing resources directory
                // being passed to FindBugs Ant task, resulting in an error
                return project.fileTree(sourceSet.getOutput().getClassesDir(), new Closure<ConfigurableFileTree>(this, this) {
                    public ConfigurableFileTree doCall(ConfigurableFileTree fileTree) {
                        return fileTree.builtBy(sourceSet.getOutput());
                    }
                });
            }
        });
        taskMapping.map("classpath", new Callable<FileCollection>() {
            @Override
            public FileCollection call() {
                return sourceSet.getCompileClasspath();
            }
        });
    }
}
