package org.embeddedt.modernfix.dynresources;

import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import com.google.common.collect.Maps;
import it.unimi.dsi.fastutil.objects.AbstractObject2IntMap;
import it.unimi.dsi.fastutil.objects.Object2IntMap;
import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
import it.unimi.dsi.fastutil.objects.ObjectSet;
import it.unimi.dsi.fastutil.objects.ObjectSets;
import it.unimi.dsi.fastutil.objects.ReferenceSets;
import net.minecraft.client.color.block.BlockColors;
import net.minecraft.client.renderer.block.model.ItemModelGenerator;
import net.minecraft.client.resources.model.BlockStateModelLoader;
import net.minecraft.client.resources.model.ClientItemInfoLoader;
import net.minecraft.client.resources.model.MissingBlockModel;
import net.minecraft.client.resources.model.ModelDiscovery;
import net.minecraft.client.resources.model.ModelManager;
import net.minecraft.client.resources.model.ResolvedModel;
import net.minecraft.client.resources.model.UnbakedModel;
import net.minecraft.resources.FileToIdConverter;
import net.minecraft.resources.Identifier;
import net.minecraft.server.packs.resources.Resource;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.block.state.BlockState;
import net.neoforged.neoforge.client.model.UnbakedModelParser;
import net.neoforged.neoforge.client.model.standalone.StandaloneModelLoader;
import org.embeddedt.modernfix.ModernFix;
import org.embeddedt.modernfix.common.mixin.perf.dynamic_resources.IdMapperAccessor;
import org.embeddedt.modernfix.common.mixin.perf.dynamic_resources.ModelDiscoveryAccessor;

import java.io.Reader;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.Set;
import java.util.function.BiFunction;
import java.util.stream.Collectors;

public class DynamicModelSystem {
    private static final FileToIdConverter MODEL_LISTER = FileToIdConverter.json("models");
    private static final FileToIdConverter BLOCKSTATE_LISTER = FileToIdConverter.json("blockstates");

    public static final boolean DEBUG_DYNAMIC_MODEL_LOADING = true; // Boolean.getBoolean("modernfix.debugDynamicModelLoading");
    
    public static Map<Identifier, UnbakedModel> createDynamicUnbakedModelMap(Map<Identifier, Resource> resourceMap) {
        LoadingCache<Identifier, UnbakedModel> unbakedModelCache = CacheBuilder.newBuilder().softValues().maximumSize(1000).build(new CacheLoader<>() {
            @Override
            public UnbakedModel load(Identifier key) throws Exception {
                var resource = resourceMap.get(MODEL_LISTER.idToFile(key));
                if (resource == null) {
                    throw new IllegalArgumentException("Model " + key + " does not exist in map");
                }
                if (DEBUG_DYNAMIC_MODEL_LOADING) {
                    ModernFix.LOGGER.info("Loading unbaked model {}", key);
                }
                try (Reader reader = resource.openAsReader()) {
                    return UnbakedModelParser.parse(reader);
                }
            }
        });
        Set<Identifier> unbakedIdSet = resourceMap.keySet().stream().map(MODEL_LISTER::fileToId).collect(Collectors.toUnmodifiableSet());
        return Maps.asMap(unbakedIdSet, key -> key != null ? unbakedModelCache.getUnchecked(key) : null);
    }

    public interface SingleBlockStateEntryLoader {
        BlockStateModelLoader.LoadedModels loadEntry(Identifier identifier, List<Resource> blockstateResources);
    }

    public static Set<BlockState> getAllBlockStates() {
        return ReferenceSets.unmodifiable(((IdMapperAccessor<BlockState>) Block.BLOCK_STATE_REGISTRY).getReferenceMap().keySet());
    }

    public static BlockStateModelLoader.LoadedModels createDynamicBlockStateLoadedModels(Map<Identifier, List<Resource>> resourceMap, SingleBlockStateEntryLoader entryLoader) {
        LoadingCache<Identifier, BlockStateModelLoader.LoadedModels> definitionCache = CacheBuilder.newBuilder().softValues().maximumSize(1000).build(new CacheLoader<>() {
            @Override
            public BlockStateModelLoader.LoadedModels load(Identifier key) throws Exception {
                if (DEBUG_DYNAMIC_MODEL_LOADING) {
                    ModernFix.LOGGER.info("Loading blockstate definition for {}", key);
                }
                var file = BLOCKSTATE_LISTER.idToFile(key);
                var resources = resourceMap.getOrDefault(file, List.of());
                return entryLoader.loadEntry(file, resources);
            }
        });
        return new BlockStateModelLoader.LoadedModels(Maps.asMap(getAllBlockStates(), state -> {
            var identifier = state.getBlock().builtInRegistryHolder().getKey().identifier();
            var loadedModels = definitionCache.getUnchecked(identifier);
            return loadedModels.models().get(state);
        }));
    }

    public record DynamicResolver(Map<Identifier, UnbakedModel> inputModels,
                                          BlockStateModelLoader.LoadedModels loadedModels,
                                          ClientItemInfoLoader.LoadedClientInfos loadedClientInfos,
                                          StandaloneModelLoader.LoadedModels standaloneModels) {

        private ResolvedModel resolveModel(Identifier id) {
            var discovery = new ModelDiscovery(inputModels, MissingBlockModel.missingModel());
            discovery.addSpecialModel(ItemModelGenerator.GENERATED_ITEM_MODEL_ID, new ItemModelGenerator());
            if (!id.equals(ItemModelGenerator.GENERATED_ITEM_MODEL_ID)) {
                UnbakedModel unbaked = inputModels.get(id);
                if (unbaked != null) {
                    var wrapper = discovery.createAndQueueWrapper(id, unbaked);
                    ((ModelDiscoveryAccessor)discovery).mfix$getModelWrappers().put(id, wrapper);
                } else {
                    ModernFix.LOGGER.warn("Cannot find the root model for {}", id);
                }
            }
            var resolved = discovery.resolve();
            return resolved.getOrDefault(id, discovery.missingModel());
        }

        public ModelManager.ResolvedModels resolvedModels() {
            var resolvedMissingModel = new ModelDiscovery(inputModels, MissingBlockModel.missingModel()).missingModel();
            LoadingCache<Identifier, ResolvedModel> resolvedModelCache = CacheBuilder.newBuilder().softValues().maximumSize(1000).build(new CacheLoader<>() {
                @Override
                public ResolvedModel load(Identifier key) {
                    return resolveModel(key);
                }
            });
            return new ModelManager.ResolvedModels(resolvedMissingModel, Maps.asMap(inputModels.keySet(), resolvedModelCache::getUnchecked));
        }
    }

    public static class BlockGroupingMap extends AbstractObject2IntMap<BlockState> {
        private final BlockColors blockColors;
        private final BlockStateModelLoader.LoadedModels loadedModels;

        record GroupKey(Object equalityGroup, List<Object> coloringValues) {}

        private final Object2IntMap<GroupKey> groupKeyToId;

        public BlockGroupingMap(BlockColors blockColors, BlockStateModelLoader.LoadedModels loadedModels) {
            this.blockColors = blockColors;
            this.loadedModels = loadedModels;
            this.groupKeyToId = new Object2IntOpenHashMap<>();
        }

        @Override
        public int size() {
            return 0;
        }

        @Override
        public ObjectSet<Entry<BlockState>> object2IntEntrySet() {
            return ObjectSets.emptySet();
        }

        @Override
        public int getInt(Object key) {
            // TODO: Implement
            return -1;
        }
    }

    public static <K, U, V> Map<K, V> createDynamicBakedRegistry(Map<K, U> input, BiFunction<K, U, V> baker) {
        // TODO: support persistence of overrides
        LoadingCache<K, Optional<V>> bakedCache = CacheBuilder.newBuilder().softValues().maximumSize(1000).build(new CacheLoader<>() {
            @Override
            public Optional<V> load(K key) throws Exception {
                var unbaked = input.get(key);
                if (unbaked != null) {
                    if (DEBUG_DYNAMIC_MODEL_LOADING) {
                        ModernFix.LOGGER.info("Baking {}", key);
                    }
                    return Optional.ofNullable(baker.apply(key, unbaked));
                } else {
                    return Optional.empty();
                }
            }
        });
        return Maps.asMap(input.keySet(), k -> k != null ? bakedCache.getUnchecked(k).orElse(null) : null);
    }
}