1 files changed, 181 insertions, 0 deletions
diff --git a/gradle-plugin/src/main/kotlin/moe/nea/mcautotranslations/gradle/MergeTranslations.kt b/gradle-plugin/src/main/kotlin/moe/nea/mcautotranslations/gradle/MergeTranslations.kt
new file mode 100644
index 0000000..44cea35
--- /dev/null
+++ b/gradle-plugin/src/main/kotlin/moe/nea/mcautotranslations/gradle/MergeTranslations.kt
@@ -0,0 +1,181 @@
+package moe.nea.mcautotranslations.gradle
+
+import com.google.gson.Gson
+import com.google.gson.reflect.TypeToken
+import moe.nea.mcautotranslations.annotations.GatheredTranslation
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.InputFiles
+import org.gradle.api.tasks.OutputFile
+import org.gradle.api.tasks.PathSensitive
+import org.gradle.api.tasks.PathSensitivity
+import org.gradle.api.tasks.TaskAction
+import org.gradle.work.Incremental
+import org.gradle.work.InputChanges
+import org.objectweb.asm.AnnotationVisitor
+import org.objectweb.asm.ClassReader
+import org.objectweb.asm.ClassVisitor
+import org.objectweb.asm.Opcodes
+import org.objectweb.asm.Type
+import java.io.File
+
+abstract class CollectTranslations : DefaultTask() {
+	@get:InputFiles
+	@get:Incremental
+	abstract val baseTranslations: ConfigurableFileCollection
+
+	@get:InputFiles
+	@get:Incremental
+	@get:PathSensitive(PathSensitivity.RELATIVE)
+	abstract val classes: ConfigurableFileCollection
+
+	@get:OutputFile
+	abstract val outputFile: RegularFileProperty
+
+	class Translations {
+		var baseTranslation: HashMap<String, HashMap<String, String>> = HashMap()
+		var inlineTranslations: HashMap<String, HashMap<String, String>> = HashMap()
+	}
+
+	companion object {
+		val gson = Gson()
+		val mapType: TypeToken<HashMap<String, String>> = object : TypeToken<HashMap<String, String>>() {}
+	}
+
+	@TaskAction
+	fun execute(inputs: InputChanges) {
+		val baseTranslationsDirty = inputs.getFileChanges(baseTranslations).any()
+		val outFile = outputFile.get().asFile
+		val outputExists = outFile.exists()
+		val canBeIncremental = outputExists && !baseTranslationsDirty
+		val baseTranslations: Translations = if (canBeIncremental) {
+			gson.fromJson(outFile.readText(), Translations::class.java)
+		} else {
+			val t = Translations()
+			baseTranslations.associateTo(t.baseTranslation) {
+				it.toString() to gson.fromJson(outFile.readText(), mapType)
+			}
+			t
+		}
+		val files: List<FileChange> = if (canBeIncremental) {
+			inputs.getFileChanges(classes).map { FileChange(it.file, it.normalizedPath) }
+		} else {
+			buildList {
+				classes.asFileTree.visit {
+					add(FileChange(it.file, it.path))
+				}
+			}
+		}
+		files
+			.asSequence()
+			.filter { checkFile(it.file) }
+			.forEach {
+				val className = getClassName(it.relativePath)
+				if (it.file.exists()) {
+					parseClassAnnotations(it.file)
+				} else {
+					baseTranslations.inlineTranslations.remove(className)
+				}
+			}
+		outFile.writeText(gson.toJson(baseTranslations))
+	}
+
+
+	private class KVVisitor(val map: MutableMap<String, String>) : AnnotationVisitor(Opcodes.ASM9) {
+		var value: String? = null
+		var key: String? = null
+		override fun visit(name: String, value: Any) {
+			when (name) {
+				"key" -> this.key = value as String
+				"value" -> this.value = value as String
+				else -> error("Unknown annotation element $name")
+			}
+		}
+
+		override fun visitAnnotation(name: String?, descriptor: String?): AnnotationVisitor {
+			error("Unknown annotation element $name")
+		}
+
+		override fun visitArray(name: String?): AnnotationVisitor {
+			error("Unknown annotation element $name")
+		}
+
+		override fun visitEnum(name: String?, descriptor: String?, value: String?) {
+			error("Unknown annotation element $name")
+		}
+
+		override fun visitEnd() {
+			map[key ?: error("Missing key")] = value ?: error("Missing value")
+		}
+	}
+
+	private class RepeatableVisitor(val map: MutableMap<String, String>) : AnnotationVisitor(Opcodes.ASM9) {
+		override fun visitArray(name: String?): AnnotationVisitor {
+			require(name == "value") { "Unknown annotation element $name" }
+			foundArray = true
+			return KVVisitor(map)
+		}
+
+		var foundArray = false
+
+		override fun visitEnd() {
+			require(foundArray) { "Missing array" }
+		}
+
+		override fun visitAnnotation(name: String?, descriptor: String?): AnnotationVisitor {
+			error("Unknown annotation element $name")
+		}
+
+		override fun visit(name: String?, value: Any?) {
+			error("Unknown annotation element $name")
+		}
+
+		override fun visitEnum(name: String?, descriptor: String?, value: String?) {
+			error("Unknown annotation element $name")
+		}
+	}
+
+	private class AnnotationCollector(val map: MutableMap<String, String>) : ClassVisitor(Opcodes.ASM9) {
+		override fun visitAnnotation(descriptor: String, visible: Boolean): AnnotationVisitor? {
+			// TODO: inject our own annotations into the classpath
+			if (Type.getType(GatheredTranslation::class.java).descriptor.equals(descriptor)) {
+				return KVVisitor(map)
+			}
+			if (Type.getType(GatheredTranslation.Repeatable::class.java).descriptor.equals(descriptor)) {
+				return RepeatableVisitor(map)
+			}
+			// TODO: remove print log
+			println("Ignoring descriptor $descriptor")
+			return null
+		}
+	}
+
+	private fun parseClassAnnotations(file: File): HashMap<String, String> {
+		val map = HashMap<String, String>()
+		kotlin.runCatching {
+			ClassReader(file.readBytes())
+				.accept(AnnotationCollector(map),
+				        ClassReader.SKIP_CODE or ClassReader.SKIP_DEBUG or ClassReader.SKIP_FRAMES)
+		}.onFailure {
+			throw RuntimeException("Could not parse annotations in $file", it)
+		}
+		return map
+	}
+
+	private fun getClassName(relativePath: String): String {
+		return relativePath.replace("/", ".").removeSuffix(".class")
+	}
+
+	data class FileChange(val file: File, val relativePath: String)
+
+	private fun checkFile(file: File): Boolean {
+		if (file.isDirectory) return false
+		val extension = file.extension
+		if (extension == "kt" || extension == "java")
+			error("Cannot collect translations from source files. Please attach the CollectTranslations task to a compile output")
+		if (extension != "class") return false
+		return true
+	}
+
+}
+\ No newline at end of file