extra_jar_def.gradle

// ===========================
// Multi-jar creation plugin
// ===========================

// How to apply:
// Copy this file into your project (completely - you don't need to change anything in this file)
// Apply this script from your main build.gradle:

/*

apply from: "extra_jar_def.gradle"

// Variables (that should be changed)
ext.mainName = "libblockattributes"
ext.mavenGroupId = "alexiil.mc.lib";

*/

// Note - you must change the "ext.mainName" and "ext.mavenGroupId" values to your own mod.

// Then call "generateJar" with the following parameters:
//   key: The name for this jar-module
//   _includes: Everything that should be included in the module
//   _excludes: Everything that should not be included in this module
//   hasMixins: If true then the refmap will be included (which is necessary for mixins)
//   required: A list of every module (that is also defined here) that is required,
//             but is not nested.
//   nestedJars: A list of every module (that is also defined here) to nest in this module
//   requiredJars: A list of every maven jar that this mod requires, but doesn't include.
//                 (The syntax is the same as "includedJars")
//   includedJars: A list of every external jar file (that must be defined with "include")
//                 to include in this module. Note that you must specify the full name of
//                 the file, except the ".jar" suffix. This should be an array with 3
//                 sections: ["maven_group", "maven_artifact_id", "file_name"]. Note that
//                 the "maven_artifact_id" will be prefixed to "file_name".
//   _manifest: A map to use for the manifest for this jar. If ommitted then this will default
//              to using "ext.extra_jar_def__common_manifest"

// Alternatively you can call "generateFatJar" which only contains a stripped version of
// the nestedJars, rather than the full one. Which also only contains stripped dependencies.

// Per-module fabric.mod.json files are generated from "diffs" of the main fabric.mod.json file:
// these should be in an object called "__buildscript_diff" in the main fabric.mod.json file.
// Then each module should declare a child with the same name as the "key" passed to "generateJar"
// Each child of *that* should be a "json-diff" of the main fabric.mod.json file, where each key
// is prefixed with one of the following:
// '-': The value won't be present in the json
// '+': The value will be added to the json, (and will replace any existing json entry)
// '~': The value must be an object, and will be applied as a json-diff.

// Optionally you can include a "__buildscript_inherit" json object which will be applied to the
// fabric.mod.json before applying per-module diffs.

// For example, given this "fabric.mod.json":

/*

{
    "id": "buildcraft",
    "name": "BuildCraft",
    "version": "$version",
    "depends": { "minecraft": "1.14.4" },
    "__buildscript_diff": {
        "core": {
            "+id": "buildcraftcore",
            "+name": "BuildCraft Core"
        },
        "transport": {
            "+id": "buildcrafttransport",
            "+name": "BuildCraft Transport",
            "+description": "Expanding minecraft with item and fluid transportation!",
            "~depends": { "+buildcraftcore": "$version" }
        }
    }
}

*/

// The following modules would be generated:

// For 'core':

/*

{
    "id": "buildcraftcore",
    "name": "BuildCraft Core",
    "version": "$version",
    "depends": {
        "minecraft": "1.14.4"
    }
}

*/

// For 'transport':

/*

{
    "id": "buildcrafttransport",
    "name": "BuildCraft Transport",
    "version": "$version",
    "depends": {
        "minecraft": "1.14.4",
        "buildcraftcore": "$version"
    },
    "description": "Expanding minecraft with item and fluid transportation!"
}

*/

// If you want to access a set of all resources included by something else you can use "ext.extra_jar_def__taken"

// For example

/*

// Custom modules
def itemsReq = [
    "alexiil/mc/lib/attributes/item/**",
    "assets/libblockattributes/icon_items.png"
];
generateJar("items", itemsReq, [], false, [], ["core"]);

*/

// ==========
// Changelog
// ==========

// 2019/09/26 AlexIIL: Add everything (and this changelog)
// 2019/09/26 AlexIIL: Add an additional section "__buildscript_inherit" to fabric.mod.json, which is applied to everything.
// 2019/09/26 AlexIIL: Add a new user variable "extra_jar_def__fabric_mod_json_replacements", for replacing additional strings in fabric.mod.json
// 2019/12/20 AlexIIL: Fix including all versions of the jars (including old versions if "gradle clean" hasn't been run)
// 2020/01/23 AlexIIL: Add "fat" jars and the option for optimised compression.

// ==========================================================
// User config - change both of these on a per-project basis
// ==========================================================

ext.mainName = "unnamed_you_need_to_redeclare_ext_dot_mainname_after_applying_extra_jar_def_gradle"
ext.mavenGroupId = "unnamed.nope"

// =================================================
// Internal config - you might need to change these
// =================================================

// The location for the "fabric.mod.json" file, relative
// to the root of the project
ext.extra_jar_def__fabricModJsonLocation = "src/main/resources/"

// If this is true then all of the dependencies declared
// by modApi or modImplementation will be removed from
// the generated POM's.
ext.extra_jar_def__clear_implicit_depedencies = true;

// All of the keys changed in fabric.mod.json.
ext.extra_jar_def__fabric_mod_json_replacements = [["\$version", project.version]];

// Common manifest for all "generateJar" callers to
// use (if they don't provide their own)
ext.extra_jar_def__common_manifest = new HashMap<String, Map<String, String>>();

// If true then nested (internally built) jars will not be compressed
// which tends to make the final (output) jar file smaller.
// (Only nested jars are not compressed - each module built will
// have two jars - the compressed one and the non-compressed one)
// Never enabled by default becuase this can lead to user confusion
// if they extract the jars and then find they're huge
// (or different to what they expect)
ext.extra_jar_def__optimised_compression = false;

// If true then included (externally built) jars will be de-compressed
// and re-zipped without compression, which tends to make the final
// (output) jar file smaller.
// Never enabled by default because of license concerns
ext.extra_jar_def__decompress_external_included = false;

// ==============================
// Internals - don't touch this!
// ==============================

ext.extra_jar_def__jarFile = zipTree(jar.archivePath)
ext.extra_jar_def__modulesDir = new File(System.getenv("LIBS_DIR") ?: "$projectDir/build/libs/", version)
ext.extra_jar_def__taken = new HashSet<>();
ext.extra_jar_def__includedJarTasks = new HashSet<String>();

def getFabricModJsonFile(String key) {
    return new File("$projectDir/build/processing/fabric_jsons/$key/${project.version}/fabric.mod.json");
}

def getFatFabricModJsonFile(String key) {
    return new File("$projectDir/build/processing/fabric_jsons_fat/$key/${project.version}/fabric.mod.json");
}

def getNestedJarFile(String key) {
    return new File("$projectDir/build/processing/nested_jars/$key/${project.version}/$mainName-$key-${project.version}.jar");
}

def getNestedStrippedJarFile(String key) {
    return new File("$projectDir/build/processing/nested_stripped_jars/$key/${project.version}/$mainName-$key-${project.version}.jar");
}

def getNestedJarContentsFolder(String key) {
    return new File("$projectDir/build/processing/nested_jars_decompressed/$key/${project.version}/");
}

def getNestedStrippedJarContentsFolder(String key) {
    return new File("$projectDir/build/processing/nested_stripped_jars_decompressed/$key/${project.version}/");
}

def getNestedSourceJarFile(String key) {
    return new File("$projectDir/build/processing/nested_jars/$key-sources/${project.version}/$mainName-$key-$project.version-sources.jar");
}

def getStrippedJarFile(String key) {
    return new File("$projectDir/build/processing/stripped_jars/$key/${project.version}/$mainName-$key-stripped-${project.version}.jar");
}

def getExpandedJarFile(String name) {
    return new File("$projectDir/build/processing/expanded_jars/$name/${name}.jar");
}

def getExpandedJarContentsFolder(String name) {
    return new File("$projectDir/build/processing/expanded_jars_decompressed/$name/");
}

ext.extra_jar_def__unzippedSourceJar = new File("$projectDir/build/processing/tasks/unzipped_src_jar/unzip")
task unzipSourcesJar(type: Copy, dependsOn: sourcesJar) {
    from (zipTree(sourcesJar.archivePath)) {
        include "**"
    }
    into extra_jar_def__unzippedSourceJar
}

def transformJson(json, diff) {
    for (entry in diff.entrySet()) {
        String jKey = entry.getKey();
        def diffValue = entry.getValue();
        char first = jKey.charAt(0);
        String realKey = jKey.substring(1)
        if (first == '-') {
            json.remove(realKey);
            continue;
        } else if (first == '+') {
            json.put(realKey, diffValue);
        } else if (first == '~') {
            def old = json.get(realKey);
            if (old == null) {
                old = new LinkedHashMap<>();
                json.put(realKey, old);
            }
            transformJson(old, diffValue);
        } else {
            throw new Error("Must be either -+~, but got " + first + "!");
        }
    }
}

def writeFabricModJsonFile(String key, List<String> addedJars, boolean fat) {
    File temp = fat ? getFatFabricModJsonFile(key) : getFabricModJsonFile(key);
    def source = new groovy.json.JsonSlurper().parse(file(extra_jar_def__fabricModJsonLocation + "fabric.mod.json"));
    temp.parentFile.mkdirs();
    if (temp.exists()) {
        temp.delete();
    }
    temp.createNewFile();
    def elements = new HashMap<>();

    def allDiff = source.remove("__buildscript_inherit");
    if (allDiff != null) {
        transformJson(source, allDiff);
    }

    def diff = source.remove("__buildscript_diff")[key];
    transformJson(source, diff);

    if (!addedJars.isEmpty()) {
        def prevJars = source.get("jars");
        if (prevJars == null) {
            prevJars = new ArrayList<>();
            source.put("jars", prevJars);
        }
        for (added in addedJars) {
            def map = new LinkedHashMap<>()
            map.put("file", added);
            prevJars.add(map);
        }
    }

    String prettyPrinted = groovy.json.JsonOutput.prettyPrint(groovy.json.JsonOutput.toJson(source));
    for (repl in extra_jar_def__fabric_mod_json_replacements) {
        prettyPrinted = prettyPrinted.replace(repl[0], repl[1]);
    }
    temp.write(prettyPrinted);

    return temp;
}

task extractAllNestedJars(type: Copy, dependsOn: tasks["remapJar"]) {
    from(project.ext.extra_jar_def__jarFile) {
        include "META-INF/jars/*.jar"
    }
    into "$projectDir/build/processing/included_jars/"
}

def readAllBytes(InputStream is) throws IOException {
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    byte[] buffer = new byte[4096];
    int read;
    while ((read = is.read(buffer)) > 0) {
        baos.write(buffer, 0, read);
    }
    return baos.toByteArray();
}

def performUnzipRezip(byte[] data) throws IOException {
    List<String> entryNames = new ArrayList<>();
    List<byte[]> entryData = new ArrayList<>();

    java.util.zip.ZipInputStream zis = new java.util.zip.ZipInputStream(new ByteArrayInputStream(data));
    java.util.zip.ZipEntry entry;
    while ((entry = zis.getNextEntry()) != null) {
        String name = entry.getName();
        byte[] read = readAllBytes(zis);

        if (name.endsWith(".jar")) {
            read = performUnzipRezip(read);
        }

        entryNames.add(name);
        entryData.add(read);
    }
    zis.close();
    ByteArrayOutputStream baos = new ByteArrayOutputStream();
    java.util.zip.ZipOutputStream zos = new java.util.zip.ZipOutputStream(baos);
    zos.setLevel(0);
    for (int i = 0; i < entryNames.size(); i++) {
        zos.putNextEntry(new java.util.zip.ZipEntry(entryNames.get(i)));
        zos.write(entryData.get(i));
        zos.closeEntry();
    }
    zos.flush();
    zos.close();
    return baos.toByteArray();
}

def unzipRezip(FileCopyDetails fcd) {

    // Unzip+rezip *in memory*
    // This makes things a lot simpler
    // (Plus I think it's unlikely that these files will get very big)

    File file = fcd.getFile();
    if (file.getName().endsWith(".jar")) {
        byte[] fd = readAllBytes(new FileInputStream(file));
        fd = performUnzipRezip(fd);
        FileOutputStream fos = new FileOutputStream(file);
        fos.write(fd);
        fos.flush();
        fos.close();
    }
}

def defineUnzipRezipTasks(
    String taskName,
    String reqTaskName,
    String _outputName,
    String _from,
    File workingDir,
    File _to
) {
    task(taskName + "_unzip", type: Copy, dependsOn: tasks[reqTaskName]) {
        from(zipTree(_from)) {
            eachFile { fcd ->
                unzipRezip(fcd);
            }
        }
        into workingDir;
    }
    task(taskName, type: Zip, dependsOn: tasks[taskName + "_unzip"]) {
        archiveName = _outputName;
        from workingDir;
        destinationDir _to;
        entryCompression ZipEntryCompression.STORED;
    }
}

def generateJarInternal(
    String key, Collection<String> _includes,
    Collection<String> _excludes, boolean hasMixins,
    List<String> required = [], List<String> nestedJars = [],
    List<List<String>> requiredJars = [],
    List<List<String>> includedJars = [], boolean fat = false,
    Map<String, Map<String, String>> _manifest = null
) {
    if (_manifest == null) {
        _manifest = ext.extra_jar_def__common_manifest;
    }

    // Sanity check
    for (int i = 0; i < includedJars.size(); i++) {
        def array = includedJars.get(i);
        if (array.size() != 3) {
            throw new IllegalArgumentException("Expected an array of length 3, but got " + array.size());
        }
        array.add(array[1] + "-" + array[2]);
        if (!array[3].endsWith(".jar")) {
            array[3] = array[3] + ".jar";
        }
    }

    def allRequired = new LinkedHashSet<>();
    allRequired.addAll(required);
    if (!fat) {
        allRequired.addAll(nestedJars);
    }

    task("writeFabricModJson_" + key) {
        doLast {
            def finalJarList = new ArrayList<>();
            for (module in nestedJars) {
               finalJarList.add("$mainName-$module" + (fat ? "-stripped" : "") + "-${version}.jar");
            }
            for (included in includedJars) {
               finalJarList.add(included[3]);
            }
            writeFabricModJsonFile(key, finalJarList, false);
        }
    }

    task("writeStrippedFabricModJson_" + key) {
        doLast {
            def finalJarList = new ArrayList<>();
            for (module in nestedJars) {
               finalJarList.add("$mainName-$module-stripped-${version}.jar");
            }
            for (included in includedJars) {
               finalJarList.add(included[3]);
            }
            writeFabricModJsonFile(key, finalJarList, true);
        }
    }

    if (ext.extra_jar_def__decompress_external_included) {
        for (nKey in includedJars) {
            if (!ext.extra_jar_def__includedJarTasks.add(nKey[1] + "-" + nKey[2])) {
                continue;
            }
            defineUnzipRezipTasks(
                "external_${nKey[1]}-${nKey[2]}",
                "extractAllNestedJars",
                "${nKey[1]}-${nKey[2]}.jar",
                "$projectDir/build/processing/included_jars/META-INF/jars/${nKey[1]}-${nKey[2]}.jar",
                getExpandedJarContentsFolder("${nKey[1]}-${nKey[2]}"),
                getExpandedJarFile("${nKey[1]}-${nKey[2]}")
            );
        }
    }

    task("submod_" + key + "Jar", type: Jar, dependsOn: "writeFabricModJson_" + key) {

        baseName = "$mainName-$key";
        destinationDir = extra_jar_def__modulesDir;

        from(getFabricModJsonFile(key).parentFile);
        for (nKey in nestedJars) {
            from(fat ? getStrippedJarFile(nKey).parentFile : getNestedJarFile(nKey).parentFile);
        }
        for (nKey in includedJars) {
            if (project.ext.extra_jar_def__decompress_external_included) {
                from(getExpandedJarFile(nKey[1] + "-" + nKey[2]));
            } else {
                from("$projectDir/build/processing/included_jars/META-INF/jars") {
                    include nKey
                }
            }
        }
        from(project.ext.extra_jar_def__jarFile) {
            excludes.add("fabric.mod.json");
            includes.addAll(_includes);
            excludes.addAll(_excludes);
            exclude "META-INF/jars/**"
            if (hasMixins) {
                includes.add(project.name + "-$key-refmap.json");
            } else {
                excludes.add(project.name + "-$key-refmap.json");
            }
        }
        manifest {
            for (Map.Entry<String, Map<String, String>> entry : _manifest.entrySet()) {
                String name = entry.getKey();
                if (name == null) {
                    attributes(entry.getValue());
                } else {
                    attributes(entry.getValue(), name);
                }
            }
        }
    }

    task("createStrippedModJar_" + key, type: Zip, dependsOn: tasks["writeStrippedFabricModJson_" + key]) {
        from(getFatFabricModJsonFile(key).parentFile);
        for (nKey in nestedJars) {
            from(getStrippedJarFile(nKey).parentFile);
        }
        for (nKey in includedJars) {
            if (project.ext.extra_jar_def__decompress_external_included) {
                from(getExpandedJarFile(nKey[1] + "-" + nKey[2]));
            } else {
                from("$projectDir/build/processing/included_jars/META-INF/jars") {
                    include nKey
                }
            }
        }
        destinationDir getStrippedJarFile(key).parentFile;
        archiveName "$mainName-$key-stripped-${project.version}.jar";
    }

    task("submod_" + key + "SourcesJar", type: Jar, dependsOn: [unzipSourcesJar, "writeFabricModJson_" + key]) {
        baseName = "$mainName-$key";
        classifier = "sources";
        destinationDir = extra_jar_def__modulesDir;
        from(getFabricModJsonFile(key).parentFile);
        for (nKey in nestedJars) {
            from(getNestedSourceJarFile(nKey).parentFile);
        }
        from (extra_jar_def__unzippedSourceJar) {
            excludes.add("fabric.mod.json");
            includes.addAll(_includes);
            excludes.addAll(_excludes);
            exclude "META-INF/jars/**"
        }
        manifest {
            for (Map.Entry<String, Map<String, String>> entry : _manifest.entrySet()) {
                String name = entry.getKey();
                if (name == null) {
                    attributes(entry.getValue());
                } else {
                    attributes(entry.getValue(), name);
                }
            }
        }
    }

    for (nKey in nestedJars) {
        tasks["submod_" + key + "Jar"].dependsOn(tasks[(fat ? "createStrippedModJar_": "copySubModJar_") + nKey])
        tasks["createStrippedModJar_" + key].dependsOn(tasks["copySubModStrippedJar_" + nKey]);
        tasks["submod_" + key + "SourcesJar"].dependsOn(tasks["copySubModSourcesJar_" + nKey])
    }

    if (ext.extra_jar_def__decompress_external_included) {
        for (nKey in includedJars) {
            tasks["submod_" + key + "Jar"].dependsOn("external_${nKey[1]}-${nKey[2]}");
            tasks["createStrippedModJar_" + key].dependsOn("external_${nKey[1]}-${nKey[2]}");
        }
    }

    if (!includedJars.isEmpty()) {
        task validateNestedJars(dependsOn: extractAllNestedJars) {
            doLast {
                for (included in includedJars) {
                    if (!new File("$projectDir/build/processing/included_jars/META-INF/jars/" + included[3]).isFile()) {
                        throw new Error("The included jar '" + included[3] + "' didn't exist! (Perhaps check the spelling?)");
                    }
                }
            }
        }
        tasks["submod_" + key + "Jar"].dependsOn(tasks["validateNestedJars"])
    }

    if (ext.extra_jar_def__optimised_compression) {
        defineUnzipRezipTasks(
            "copySubModJar_" + key,
            "submod_" + key + "Jar",
            "$mainName-$key-${project.version}.jar",
            "" + extra_jar_def__modulesDir + "/$mainName-$key-${project.version}.jar",
            getNestedJarContentsFolder(key),
            getNestedJarFile(key).parentFile
        );

        defineUnzipRezipTasks(
            "copySubModStrippedJar_" + key,
            "createStrippedModJar_" + key,
            "$mainName-$key-${project.version}.jar",
            "" + getStrippedJarFile(key),
            getNestedStrippedJarContentsFolder(key),
            getNestedStrippedJarFile(key).parentFile
        );
    } else {
        task("copySubModJar_" + key, type: Copy, dependsOn: tasks["submod_" + key + "Jar"]) {
            from "" + extra_jar_def__modulesDir + "/$mainName-$key-${project.version}.jar";
            into getNestedJarFile(key).parentFile;
        }

        task("copySubModStrippedJar_" + key, type: Copy, dependsOn: tasks["createStrippedModJar_" + key]) {
            from getStrippedJarFile(key);
            into getNestedStrippedJarFile(key).parentFile;
        }
    }

    task("copySubModSourcesJar_" + key, type: Copy, dependsOn: tasks["submod_" + key + "SourcesJar"]) {
        from "" + extra_jar_def__modulesDir + "/$mainName-$key-$project.version-sources.jar";
        into getNestedSourceJarFile(key).parentFile;
    }

    extra_jar_def__taken.addAll(_includes);
    build.dependsOn("submod_" + key + "Jar");
    build.dependsOn("submod_" + key + "SourcesJar");

    publishing.publications.create("publishJars_" + key, MavenPublication) {
        groupId "$mavenGroupId"
        artifactId "$mainName-$key";
        version project.version

        artifact tasks["submod_" + key + "Jar"]
        artifact tasks["submod_" + key + "SourcesJar"]

        pom {
            dependencies {
                // FIXME: For some reason this doesn't work :(
                // clear();
            }
        }

        // Otherwise the value of key is lost?
        def k = key;
        pom.withXml {
            def root = asNode();
            // def required = extra_jar_def__requiredJars.get(k);
            if (!allRequired.isEmpty() || !requiredJars.isEmpty() || !includedJars.isEmpty() || extra_jar_def__clear_implicit_depedencies) {
                def hasFinished = false;

                // Gradle (or fabric loom or the maven publish plugin, I don't know which)
                // doesn't respect the definition of "modImplementation". So we return a
                // different Node class that refuses to add any additional dependencies after
                // we have finished. (Although only if this behaviour hasn't been disabled by
                // the real project, as some people may want the normal behaviour)
                Node deps = new Node(root, "dependencies") {
                    @Override
                    def Node appendNode(Object nodeKey) {
                        if (hasFinished) {
                            return new Node(null, nodeKey);
                        }
                        return super.appendNode(nodeKey);
                    }
                };

                for (dep in allRequired) {
                    Node depNode = deps.appendNode('dependency');
                    depNode.appendNode('groupId', "$mavenGroupId");
                    depNode.appendNode('artifactId', "$mainName-" + dep);
                    depNode.appendNode('version', project.version);
                    depNode.appendNode('scope', 'compile');
                }

                for (dep in requiredJars) {
                    Node depNode = deps.appendNode('dependency');
                    depNode.appendNode('groupId', dep[0]);
                    depNode.appendNode('artifactId', dep[1]);
                    depNode.appendNode('version', dep[2]);
                    depNode.appendNode('scope', 'compile');
                }

                for (dep in includedJars) {
                    Node depNode = deps.appendNode('dependency');
                    depNode.appendNode('groupId', dep[0]);
                    depNode.appendNode('artifactId', dep[1]);
                    depNode.appendNode('version', dep[2]);
                    depNode.appendNode('scope', 'compile');
                }

                if (extra_jar_def__clear_implicit_depedencies) {
                    hasFinished = true;
                }
            }
        }
    }
}

def generateJar(
    String key, Collection<String> _includes,
    Collection<String> _excludes, boolean hasMixins,
    List<String> required = [], List<String> nestedJars = [],
    List<List<String>> requiredJars = [],
    List<List<String>> includedJars = [],
    Map<String, Map<String, String>> _manifest = null
) {
    generateJarInternal(key, _includes, _excludes, hasMixins,
        required, nestedJars, requiredJars, includedJars,
        false, _manifest);
}

def generateFatJar(
    String key, Collection<String> _includes,
    Collection<String> _excludes, boolean hasMixins,
    List<String> required = [], List<String> nestedJars = [],
    List<List<String>> requiredJars = [],
    List<List<String>> includedJars = [],
    Map<String, Map<String, String>> _manifest = null
) {
    generateJarInternal(key, _includes, _excludes, hasMixins,
        required, nestedJars, requiredJars, includedJars,
        true, _manifest);
}

tasks.publish.dependsOn(tasks.build)
tasks.publishToMavenLocal.dependsOn(tasks.build)

ext.generateJar = this.&generateJar
ext.generateFatJar = this.&generateFatJar