gradle/helper.gradle

import java.nio.file.Path
import java.nio.file.Paths
import java.nio.file.Files
import java.text.MessageFormat


class UpdateLibrariesTask extends DefaultTask {
	Path directory
	List<Map> libraries
	Set<String> manualLibraries = new HashSet<>();

	@TaskAction
	def update() {
		Set<String> librariesNames = new HashSet<>()

		libraries.each({
			String url = it.get("url")
			String libraryName = it.get("name")

			librariesNames.add(libraryName)

			Path libraryFile = directory.resolve(libraryName)
			if (Files.notExists(libraryFile)) {
				logger.lifecycle(MessageFormat.format("Downloading library {0} from {1}", libraryName, url))
				ant.get(src: url, dest: libraryFile)
			} else {
				logger.lifecycle(MessageFormat.format("Skipping download of library {0} because it already exists", libraryName))
			}
		})

		Files.list(directory)
		.filter({
			String filename = it.getFileName().toString()
			!librariesNames.contains(filename) && !manualLibraries.contains(filename)
		})
		.each({
			logger.lifecycle(MessageFormat.format("Deleting old library {0}", it.getFileName()))
			Files.delete(it)
		})
	}

}

ext.UpdateLibrariesTask = UpdateLibrariesTask


class BuildLibraryTask extends DefaultTask {
	Path targetDirectory
	String targetLibraryName
	String builderUrl
	String buildCommand
	String[] builtLibraryName
	String builderName = "library_builder"

	@TaskAction
	def update() {
		Path libraryFile = targetDirectory.resolve(targetLibraryName)
		Path buildDirectory = getProject().buildDir.toPath().toAbsolutePath().resolve("libraries").resolve(targetLibraryName)
		Files.createDirectories(buildDirectory)
		if (Files.notExists(libraryFile)) {
			logger.lifecycle(MessageFormat.format("Building library {0} from {1}", targetLibraryName, builderUrl))
			ant.get(src: builderUrl, dest: buildDirectory.resolve(builderName))
			getProject().exec {
				workingDir = buildDirectory.toFile()
				commandLine = buildCommand.replace("{BUILDER}", builderName).split("\\s+")
			}
			Path builtLibraryFile = buildDirectory
			for (String builtLibraryElementName : builtLibraryName) {
				builtLibraryFile = builtLibraryFile.resolve(builtLibraryElementName)
			}
			Files.copy(builtLibraryFile, libraryFile)
		} else {
			logger.lifecycle(MessageFormat.format("Skipping building of library {0} because it already exists", targetLibraryName))
		}
	}
}

ext.BuildLibraryTask = BuildLibraryTask