/*

 * Copyright (c) 2015, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package toolbox;

import java.io.File;

import java.io.IOException;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.LinkedHashSet;

import java.util.List;

import java.util.Set;

import java.util.stream.Collectors;

/**

 * Builder for module declarations.

 */

public class ModuleBuilder {

    private final ToolBox tb;

    private final String name;

    private String comment = "";

    private boolean open;

    private List<String> requires = new ArrayList<>();

    private List<String> exports = new ArrayList<>();

    private List<String> opens = new ArrayList<>();

    private List<String> uses = new ArrayList<>();

    private List<String> provides = new ArrayList<>();

    private List<String> content = new ArrayList<>();

    private Set<Path> modulePath = new LinkedHashSet<>();

    /**

     * Creates a builder for a module.

     * @param tb a Toolbox that can be used to compile the module declaration

     * @param name the name of the module to be built

     */

    public ModuleBuilder(ToolBox tb, String name) {

        this(tb, false, name);

    }

    /**

     * Creates a builder for a module.

     * @param tb a Toolbox that can be used to compile the module declaration

     * @param open whether or not this is an open module

     * @param name the name of the module to be built

     */

    public ModuleBuilder(ToolBox tb, boolean open, String name) {

        this.tb = tb;

        this.open = open;

        this.name = name;

    }

    /**

     * Sets the doc comment for the declaration.

     * @param comment the content of the comment, excluding the initial

     *  '/**', leading whitespace and asterisks, and the final trailing '&#02a;/'.

     * @return this builder

     */

    public ModuleBuilder comment(String comment) {

        this.comment = comment;

        return this;

    }

    /**

     * Adds a "requires" directive to the declaration.

     * @param module the name of the module that is required

     * @param modulePath a path in while to locate the modules

     *    if the declaration is compiled

     * @return this builder

     */

    public ModuleBuilder requires(String module, Path... modulePath) {

        addDirective(requires, "requires " + module + ";");

        this.modulePath.addAll(Arrays.asList(modulePath));

        return this;

    }

    /**

     * Adds a "requires static" directive to the declaration.

     * @param module the name of the module that is required

     * @param modulePath a path in which to locate the modules

     *    if the declaration is compiled

     * @return this builder

     */

    public ModuleBuilder requiresStatic(String module, Path... modulePath) {

        addDirective(requires, "requires static " + module + ";");

        this.modulePath.addAll(Arrays.asList(modulePath));

        return this;

    }

    /**

     * Adds a "requires transitive" directive to the declaration.

     * @param module the name of the module that is required

     * @param modulePath a path in which to locate the modules

     *    if the declaration is compiled

     * @return this builder

     */

    public ModuleBuilder requiresTransitive(String module, Path... modulePath) {

        addDirective(requires, "requires transitive " + module + ";");

        this.modulePath.addAll(Arrays.asList(modulePath));

        return this;

    }

    /**

     * Adds a "requires static transitive" directive to the declaration.

     * @param module the name of the module that is required

     * @param modulePath a path in which to locate the modules

     *    if the declaration is compiled

     * @return this builder

     */

    public ModuleBuilder requiresStaticTransitive(String module, Path... modulePath) {

        addDirective(requires, "requires static transitive " + module + ";");

        this.modulePath.addAll(Arrays.asList(modulePath));

        return this;

    }

    /**

     * Adds an unqualified "exports" directive to the declaration.

     * @param pkg the name of the package to be exported

     * @return this builder

     */

    public ModuleBuilder exports(String pkg) {

        return addDirective(exports, "exports " + pkg + ";");

    }

    /**

     * Adds a qualified "exports" directive to the declaration.

     * @param pkg the name of the package to be exported

     * @param module the name of the module to which it is to be exported

     * @return this builder

     */

    public ModuleBuilder exportsTo(String pkg, String module) {

        return addDirective(exports, "exports " + pkg + " to " + module + ";");

    }

    /**

     * Adds an unqualified "opens" directive to the declaration.

     * @param pkg the name of the package to be opened

     * @return this builder

     */

    public ModuleBuilder opens(String pkg) {

        return addDirective(opens, "opens " + pkg + ";");

    }

    /**

     * Adds a qualified "opens" directive to the declaration.

     * @param pkg the name of the package to be opened

     * @param module the name of the module to which it is to be opened

     * @return this builder

     */

    public ModuleBuilder opensTo(String pkg, String module) {

        return addDirective(opens, "opens " + pkg + " to " + module + ";");

    }

    /**

     * Adds a "uses" directive to the declaration.

     * @param service the name of the service type

     * @return this builder

     */

    public ModuleBuilder uses(String service) {

        return addDirective(uses, "uses " + service + ";");

    }

    /**

     * Adds a "provides" directive to the declaration.

     * @param service the name of the service type

     * @param implementation the name of the implementation type

     * @return this builder

     */

    public ModuleBuilder provides(String service, String implementation) {

        return addDirective(provides, "provides " + service + " with " + implementation + ";");

    }

    private ModuleBuilder addDirective(List<String> directives, String directive) {

        directives.add(directive);

        return this;

    }

    /**

     * Adds type definitions to the module.

     * @param content a series of strings, each representing the content of

     *  a compilation unit to be included with the module

     * @return this builder

     */

    public ModuleBuilder classes(String... content) {

        this.content.addAll(Arrays.asList(content));

        return this;

    }

    /**

     * Writes the module declaration and associated additional compilation

     * units to a module directory within a given directory.

     * @param srcDir the directory in which a directory will be created

     *  to contain the source files for the module

     * @return the directory containing the source files for the module

     */

    public Path write(Path srcDir) throws IOException {

        Files.createDirectories(srcDir);

        List<String> sources = new ArrayList<>();

        StringBuilder sb = new StringBuilder();

        if (!comment.isEmpty()) {

            sb.append("/**\n * ")

                    .append(comment.replace("\n", "\n * "))

                    .append("\n */\n");

        }

        if (open) {

            sb.append("open ");

        }

        sb.append("module ").append(name).append(" {\n");

        requires.forEach(r -> sb.append("    " + r + "\n"));

        exports.forEach(e -> sb.append("    " + e + "\n"));

        opens.forEach(o -> sb.append("    " + o + "\n"));

        uses.forEach(u -> sb.append("    " + u + "\n"));

        provides.forEach(p -> sb.append("    " + p + "\n"));

        sb.append("}");

        sources.add(sb.toString());

        sources.addAll(content);

        Path moduleSrc = srcDir.resolve(name);

        tb.writeJavaFiles(moduleSrc, sources.toArray(new String[]{}));

        return moduleSrc;

    }

    /**

     * Writes the source files for the module to an interim directory,

     * and then compiles them to a given directory.

     * @param modules the directory in which a directory will be created

     *    to contain the compiled class files for the module

     * @throws IOException if an error occurs while compiling the files

     */

    public void build(Path modules) throws IOException {

        build(Paths.get(modules + "Src"), modules);

    }

    /**

     * Writes the source files for the module to a specified directory,

     * and then compiles them to a given directory.

     * @param srcDir the directory in which a directory will be created

     *  to contain the source files for the module

     * @param modules the directory in which a directory will be created

     *    to contain the compiled class files for the module

     * @throws IOException if an error occurs while compiling the files

     */

    public void build(Path src, Path modules) throws IOException {

        Path moduleSrc = write(src);

        String mp = modulePath.stream()

                .map(Path::toString)

                .collect(Collectors.joining(File.pathSeparator));

        new JavacTask(tb)

                .outdir(Files.createDirectories(modules.resolve(name)))

                .options("--module-path", mp)

                .files(tb.findJavaFiles(moduleSrc))

                .run()

                .writeAll();

    }

}