/*
 * This file is part of fabric-loom, licensed under the MIT License (MIT).
 *
 * Copyright (c) 2016, 2017, 2018 FabricMC
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package net.fabricmc.loom.util;

import com.google.common.base.Charsets;
import com.google.common.io.ByteStreams;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import net.fabricmc.loom.LoomGradleExtension;
import net.fabricmc.loom.mixin.MixinMappingProviderTiny;
import net.fabricmc.tinyremapper.OutputConsumerPath;
import net.fabricmc.tinyremapper.TinyRemapper;
import net.fabricmc.tinyremapper.TinyUtils;
import org.apache.commons.io.IOUtils;
import org.gradle.api.Project;
import org.gradle.api.artifacts.Configuration;
import org.gradle.api.artifacts.ExternalModuleDependency;
import org.gradle.api.artifacts.repositories.MavenArtifactRepository;
import org.objectweb.asm.commons.Remapper;
import org.spongepowered.asm.mixin.injection.struct.MemberInfo;
import org.spongepowered.asm.obfuscation.mapping.common.MappingField;
import org.spongepowered.asm.obfuscation.mapping.common.MappingMethod;
import org.zeroturnaround.zip.ZipUtil;
import org.zeroturnaround.zip.transform.StringZipEntryTransformer;
import org.zeroturnaround.zip.transform.ZipEntryTransformerEntry;

import java.io.*;
import java.lang.reflect.Field;
import java.nio.charset.StandardCharsets;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.jar.JarFile;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class ModProcessor {

	public static void handleMod(File input, File output, Project project){
		if(output.exists()){
			output.delete();
		}
		remapJar(input, output, project);

		JsonObject jsonObject = readInstallerJson(input);
		if(jsonObject != null){
			handleInstallerJson(jsonObject, project);
		}
	}

	private static void remapJar(File input, File output, Project project){
		LoomGradleExtension extension = project.getExtensions().getByType(LoomGradleExtension.class);
		String fromM = "intermediary";
		String toM = "pomf";

		File mappingsFile = Constants.MAPPINGS_TINY.get(extension);
		Path mappings = mappingsFile.toPath();
		Path mc = Constants.MINECRAFT_INTERMEDIARY_JAR.get(extension).toPath();
		Path[] classpath = project.getConfigurations().getByName(Constants.CONFIG_MC_DEPENDENCIES).getFiles().stream()
			.map(File::toPath)
			.toArray(Path[]::new);

		project.getLogger().lifecycle(":remapping " + input.getName() + " (TinyRemapper, " + fromM + " -> " + toM + ")");

		TinyRemapper remapper = TinyRemapper.newRemapper()
			.withMappings(TinyUtils.createTinyMappingProvider(mappings, fromM, toM))
			.build();

		try {
			OutputConsumerPath outputConsumer = new OutputConsumerPath(Paths.get(output.getAbsolutePath()));
			outputConsumer.addNonClassFiles(input.toPath());
			remapper.read(input.toPath());
			remapper.read(mc);
			remapper.read(classpath);
			remapper.apply(input.toPath(), outputConsumer);
			outputConsumer.finish();
		} catch (Exception e){
			remapper.finish();
			throw new RuntimeException("Failed to remap JAR to " + toM, e);
		}
		if(!output.exists()){
			throw new RuntimeException("Failed to remap JAR to " + toM + " file not found: " + output.getAbsolutePath());
		}

		Gson gson = new GsonBuilder().setPrettyPrinting().create();
		project.getLogger().lifecycle(":remapping " + input.getName() + " (Mixin reference map)");
		// first, identify all of the mixin refmaps
		Set<String> mixinRefmapFilenames = new HashSet<>();
		// TODO: this is a lovely hack
		ZipUtil.iterate(output, (stream, entry) -> {
			if (!entry.isDirectory() && entry.getName().endsWith(".json") && !entry.getName().contains("/") && !entry.getName().contains("\\")) {
				// JSON file in root directory
				try {
					JsonObject json = gson.fromJson(new InputStreamReader(stream), JsonObject.class);
					if (json != null && json.has("refmap")) {
						mixinRefmapFilenames.add(json.get("refmap").getAsString());
					}
				} catch (Exception e) {
					// ...
				}
			}
		});

		if (mixinRefmapFilenames.size() > 0) {
			Remapper asmRemapper;
			// TODO: Expose in tiny-remapper
			try {
				Field f = TinyRemapper.class.getDeclaredField("remapper");;
				f.setAccessible(true);
				asmRemapper = (Remapper) f.get(remapper);
			} catch (Exception e) {
				throw new RuntimeException(e);
			}

			ZipUtil.transformEntries(
					output,
					mixinRefmapFilenames.stream()
						.map((f) -> new ZipEntryTransformerEntry(f, new StringZipEntryTransformer("UTF-8") {
							@Override
							protected String transform(ZipEntry zipEntry, String input) throws IOException {
								return transformRefmap(asmRemapper, gson, input);
							}
						})).toArray(ZipEntryTransformerEntry[]::new)
			);

			remapper.finish();
		}
	}

	public static String transformRefmap(Remapper remapper, Gson gson, String input) throws IOException {
		try {
			JsonObject refMap = gson.fromJson(input, JsonObject.class);
			JsonObject mappings = refMap.getAsJsonObject("mappings");

			for (Map.Entry<String, JsonElement> elementEntry : mappings.entrySet()) {
				JsonObject value = elementEntry.getValue().getAsJsonObject();
				for (String k : new HashSet<>(value.keySet())) {
					try {
						String v = value.get(k).getAsString();
						String v2;

						if (v.charAt(0) == 'L') {
							// field or member
							MemberInfo info = MemberInfo.parse(v);
							String owner = remapper.map(info.owner);
							if (info.isField()) {
								v2 = new MemberInfo(
										remapper.mapFieldName(info.owner, info.name, info.desc),
										owner,
										remapper.mapDesc(info.desc)
								).toString();
							} else {
								v2 = new MemberInfo(
										remapper.mapMethodName(info.owner, info.name, info.desc),
										owner,
										remapper.mapMethodDesc(info.desc)
								).toString();
							}
						} else {
							// class
							v2 = remapper.map(v);
						}

						if (v2 != null) {
							value.addProperty(k, v2);
						}
					} catch (Exception ee) {
						ee.printStackTrace();
					}
				}
			}

			return gson.toJson(refMap);
		} catch (Exception e) {
			e.printStackTrace();
			return input;
		}
	}

	private static void handleInstallerJson(JsonObject jsonObject, Project project){
		JsonObject libraries = jsonObject.get("libraries").getAsJsonObject();
		libraries.get("common").getAsJsonArray().forEach(jsonElement -> {
			String name = jsonElement.getAsJsonObject().get("name").getAsString();

			Configuration configuration = project.getConfigurations().getByName("compile");
			ExternalModuleDependency modDep = (ExternalModuleDependency) project.getDependencies().create(name);
			modDep.setTransitive(false);
			configuration.getDependencies().add(modDep);

			if(jsonElement.getAsJsonObject().has("url")){
				String url = jsonElement.getAsJsonObject().get("url").getAsString();
				long count = project.getRepositories().stream()
					.filter(artifactRepository -> artifactRepository instanceof MavenArtifactRepository)
					.map(artifactRepository -> (MavenArtifactRepository) artifactRepository)
					.filter(mavenArtifactRepository -> mavenArtifactRepository.getUrl().toString().equalsIgnoreCase(url)).count();
				if(count == 0){
					project.getRepositories().maven(mavenArtifactRepository -> mavenArtifactRepository.setUrl(jsonElement.getAsJsonObject().get("url").getAsString()));
				}

			}
		});
	}

	private static JsonObject readInstallerJson(File file){
		try {
			JarFile jarFile = new JarFile(file);
			ZipEntry entry = jarFile.getEntry("fabric-installer.json");
			if(entry == null){
				return null;
			}
			InputStream inputstream = jarFile.getInputStream(entry);
			String jsonStr = IOUtils.toString(inputstream, StandardCharsets.UTF_8);
			inputstream.close();
			jarFile.close();

			JsonObject jsonObject = new Gson().fromJson(jsonStr, JsonObject.class);
			return jsonObject;
		} catch (IOException e) {
			e.printStackTrace();
			return null;
		}
	}

}