/*
 * 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 org.apache.freemarker.generator.maven;

import freemarker.cache.FileTemplateLoader;
import freemarker.template.Configuration;
import mockit.Expectations;
import mockit.Mocked;
import org.apache.maven.execution.MavenSession;
import org.apache.maven.project.MavenProject;
import org.junit.Assert;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;

import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.FileVisitResult;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import static org.assertj.core.api.Assertions.*;

public class GeneratingFileVisitorTest extends Assert {

    private static File testDir = new File("src/test/data/generating-file-visitor");
    private static File dataDir = new File(testDir, "data");
    private static File templateDir = new File(testDir, "template");
    private static File outputDir = new File("target/test-output/generating-file-visitor");
    private static Map<String, OutputGeneratorPropertiesProvider> builders = new HashMap<>();
    private Configuration config;
    private Properties pomProperties = new Properties();

    @BeforeClass
    public static void beforeClass() throws IOException {
        builders.put(".json", JsonPropertiesProvider.create(dataDir, templateDir, outputDir));
        // Clean output dir before each run.
        File outputDir = new File("target/test-output/generating-file-visitor");
        if (outputDir.exists()) {
            // Recursively delete output from previous run.
            Files.walk(outputDir.toPath())
                    .sorted(Comparator.reverseOrder())
                    .map(Path::toFile)
                    .forEach(File::delete);
        }
    }

    @BeforeMethod
    public void before() throws IOException {
        if (!testDir.isDirectory()) {
            throw new RuntimeException("Can't find required test data directory. "
                    + "If running test outside of maven, make sure working directory is the project directory. "
                    + "Looking for: " + testDir);
        }

        config = new Configuration(Configuration.VERSION_2_3_23);
        config.setDefaultEncoding("UTF-8");
        config.setTemplateLoader(new FileTemplateLoader(templateDir));
        pomProperties.put("pomVar", "pom value");
    }

    @Test
    public void functionalHappyPathTestNoDataModel(
            @Mocked MavenSession session,
            @Mocked MavenProject project,
            @Mocked File mockFile,
            @Mocked BasicFileAttributes attrs) throws IOException {
        List<MavenProject> projects = new ArrayList<>();
        projects.add(project);
        new Expectations(session, project, mockFile) {{
            session.getCurrentProject();
            result = project;
            session.getAllProjects();
            result = projects;
            project.getProperties();
            result = pomProperties;
            attrs.isRegularFile();
            result = true;
            project.getFile();
            result = mockFile;
            mockFile.lastModified();
            result = 10;
        }};

        File file = new File(dataDir, "mydir/success-test-2.txt.json");
        GeneratingFileVisitor gfv = GeneratingFileVisitor.create(config, session, builders);
        assertEquals(FileVisitResult.CONTINUE, gfv.visitFile(file.toPath(), attrs));

        File outputFile = new File(outputDir, "mydir/success-test-2.txt");
        assertTrue(outputFile.isFile());
        List<String> lines = Files.readAllLines(outputFile.toPath(), StandardCharsets.UTF_8);
        assertEquals(17, lines.size());
        assertEquals("This is a test freemarker template. Test pom data: 'pom value'.", lines.get(16));
    }

    @Test
    public void functionalHappyPathTest(
            @Mocked MavenSession session,
            @Mocked MavenProject project,
            @Mocked File mockFile,
            @Mocked BasicFileAttributes attrs) throws IOException {
        List<MavenProject> projects = new ArrayList<>();
        projects.add(project);
        new Expectations(session, project, mockFile) {{
            session.getCurrentProject();
            result = project;
            session.getAllProjects();
            result = projects;
            project.getProperties();
            result = pomProperties;
            attrs.isRegularFile();
            result = true;
            project.getFile();
            result = mockFile;
            mockFile.lastModified();
            result = 10;
        }};

        File file = new File(dataDir, "mydir/success-test.txt.json");
        GeneratingFileVisitor gfv = GeneratingFileVisitor.create(config, session, builders);
        assertEquals(FileVisitResult.CONTINUE, gfv.visitFile(file.toPath(), attrs));

        File outputFile = new File(outputDir, "mydir/success-test.txt");
        assertTrue(outputFile.isFile());
        List<String> lines = Files.readAllLines(outputFile.toPath(), StandardCharsets.UTF_8);
        assertEquals(17, lines.size());
        assertEquals("This is a test freemarker template. Test json data: 'test value'. Test pom data: 'pom value'.", lines
                .get(16));
    }

    @Test
    public void visitFile_badExtensionTest(
            @Mocked MavenSession session,
            @Mocked MavenProject project,
            @Mocked File mockFile,
            @Mocked BasicFileAttributes attrs) throws IOException {
        List<MavenProject> projects = new ArrayList<>();
        projects.add(project);
        new Expectations(session, project, mockFile) {{
            attrs.isRegularFile();
            result = true;
            session.getAllProjects();
            result = projects;
            project.getFile();
            result = mockFile;
            mockFile.lastModified();
            result = 10;
        }};
        // Test file without .json suffix.
        File file = new File(dataDir, "mydir/bad-extension-test.txt");
        GeneratingFileVisitor gfv = GeneratingFileVisitor.create(config, session, builders);
        assertThatExceptionOfType(RuntimeException.class).isThrownBy(() -> {
            gfv.visitFile(file.toPath(), attrs);
        }).withMessage("Unknown file extension: " + file.toPath());
    }

    @Test
    public void visitFile_notRegularFileTest(@Mocked MavenSession session,
                                             @Mocked MavenProject project,
                                             @Mocked BasicFileAttributes attrs,
                                             @Mocked File mockFile
    ) {
        List<MavenProject> projects = new ArrayList<>();
        projects.add(project);
        new Expectations(session, project, mockFile) {{
            attrs.isRegularFile();
            result = false;
            session.getAllProjects();
            result = projects;
            project.getFile();
            result = mockFile;
            mockFile.lastModified();
            result = 10;
        }};
        // FYI: if you change above result to true, test will fail trying to read the 'mydir' directory
        // as a json file.
        File dir = new File(dataDir, "mydir");
        GeneratingFileVisitor gfv = GeneratingFileVisitor.create(config, session, builders);
        assertEquals(FileVisitResult.CONTINUE, gfv.visitFile(dir.toPath(), attrs));
    }
}