/*
 * Minecraft Forge
 * Copyright (c) 2016-2019.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation version 2.1
 * of the License.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

package net.minecraftforge.fml.loading;

import com.google.common.collect.Streams;
import net.minecraftforge.fml.loading.moddiscovery.BackgroundScanHandler;
import net.minecraftforge.fml.loading.moddiscovery.ModFile;
import net.minecraftforge.fml.loading.moddiscovery.ModFileInfo;
import net.minecraftforge.fml.loading.moddiscovery.ModInfo;

import java.net.MalformedURLException;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

/**
 * Master list of all mods <em>in the loading context. This class cannot refer outside the
 * loading package</em>
 */
public class LoadingModList
{
    private static LoadingModList INSTANCE;
    private final List<ModFileInfo> modFiles;
    private final List<ModInfo> sortedList;
    private final Map<String, ModFileInfo> fileById;
    private BackgroundScanHandler scanner;
    private final List<EarlyLoadingException> preLoadErrors;

    private LoadingModList(final List<ModFile> modFiles, final List<ModInfo> sortedList)
    {
        this.modFiles = modFiles.stream().map(ModFile::getModFileInfo).map(ModFileInfo.class::cast).collect(Collectors.toList());
        this.sortedList = Streams.concat(DefaultModInfos.getModInfos().stream(), sortedList.stream()).
                map(ModInfo.class::cast).
                collect(Collectors.toList());
        this.fileById = this.modFiles.stream().map(ModFileInfo::getMods).flatMap(Collection::stream).
                map(ModInfo.class::cast).
                collect(Collectors.toMap(ModInfo::getModId, ModInfo::getOwningFile));
        this.preLoadErrors = new ArrayList<>();
    }

    public static LoadingModList of(List<ModFile> modFiles, List<ModInfo> sortedList, final EarlyLoadingException earlyLoadingException)
    {
        INSTANCE = new LoadingModList(modFiles, sortedList);
        if (earlyLoadingException != null)
        {
            INSTANCE.preLoadErrors.add(earlyLoadingException);
        }
        return INSTANCE;
    }

    public static LoadingModList get() {
        return INSTANCE;
    }
    public void addCoreMods()
    {
        modFiles.stream().map(ModFileInfo::getFile).map(ModFile::getCoreMods).flatMap(List::stream).forEach(FMLLoader.getCoreModProvider()::addCoreMod);
    }

    public void addAccessTransformers()
    {
        modFiles.stream().map(ModFileInfo::getFile).forEach(mod -> mod.getAccessTransformer().ifPresent(path -> FMLLoader.addAccessTransformer(path, mod)));
    }

    public void addForScanning(BackgroundScanHandler backgroundScanHandler)
    {
        this.scanner = backgroundScanHandler;
        backgroundScanHandler.setLoadingModList(this);
        modFiles.stream().map(ModFileInfo::getFile).forEach(backgroundScanHandler::submitForScanning);
    }

    public List<ModFileInfo> getModFiles()
    {
        return modFiles;
    }

    public Path findResource(final String className)
    {
        for (ModFileInfo mf : modFiles) {
            final Path resource = mf.getFile().findResource(className);
            if (Files.exists(resource)) return resource;
        }
        return null;
    }

    public URL findURLForResource(final String resourceName) {
        for (ModFileInfo mf : modFiles) {
            final Path resource = mf.getFile().findResource(resourceName);
            if (Files.exists(resource)) {
                try {
                    return new URL("modjar://"+mf.getMods().get(0).getModId()+"/"+resourceName);
                } catch (MalformedURLException e) {
                    throw new RuntimeException(e);
                }
            }
        }
        return null;
    }

    public ModFileInfo getModFileById(String modid)
    {
        return this.fileById.get(modid);
    }

    public List<ModInfo> getMods()
    {
        return this.sortedList;
    }

    public List<EarlyLoadingException> getErrors() {
        return preLoadErrors;
    }
}