package io.gitlab.jfronny.respackopts.filters;

import io.gitlab.jfronny.libjf.ResourcePath;
import io.gitlab.jfronny.libjf.data.manipulation.api.UserResourceEvents;
import io.gitlab.jfronny.muscript.debug.ObjectGraphPrinter;
import io.gitlab.jfronny.respackopts.Respackopts;
import io.gitlab.jfronny.respackopts.gson.AttachmentHolder;
import io.gitlab.jfronny.respackopts.model.Condition;
import io.gitlab.jfronny.respackopts.model.DirRpo;
import io.gitlab.jfronny.respackopts.model.cache.CacheKey;
import io.gitlab.jfronny.respackopts.model.cache.CachedPackState;
import io.gitlab.jfronny.respackopts.model.enums.PackCapability;
import io.gitlab.jfronny.respackopts.util.MetaCache;
import net.minecraft.resource.*;
import net.minecraft.util.Identifier;

import java.io.*;
import java.util.Map;

public enum DirFilterEvents implements UserResourceEvents.Open, UserResourceEvents.FindResource {
    INSTANCE;

    public static void init() {
        UserResourceEvents.OPEN.register(INSTANCE);
        UserResourceEvents.FIND_RESOURCE.register(INSTANCE);
    }

    @Override
    public InputSupplier<InputStream> open(ResourceType type, Identifier id, InputSupplier<InputStream> previous, ResourcePack pack) {
        if (!MetaCache.hasCapability(pack, PackCapability.DirFilter)) return previous;
        String path = new ResourcePath(type, id).getName();
        DirRpo rpo = findDirRpo(pack, path);
        if (rpo != null && dirHidden(rpo, MetaCache.getKeyByPack(pack), path)) {
            path = findReplacementDir(path, rpo);
            if (path == null) return null;
            ResourcePath rp = new ResourcePath(path);
            return pack.open(rp.getType(), rp.getId());
        }
        return previous;
    }

    @Override
    public ResourcePack.ResultConsumer findResources(ResourceType type, String namespace, String prefix, ResourcePack.ResultConsumer previous, ResourcePack pack) {
        // Warning: the Identifiers here DON'T CONTAIN THE TYPE!
        // Therefore, it needs to be added when calling a method that generates a ResourcePath!
        if (!MetaCache.hasCapability(pack, PackCapability.DirFilter)) return previous;
        boolean dirFilterAdditive = MetaCache.hasCapability(pack, PackCapability.DirFilterAdditive);
        return (identifier, value) -> {
            String path = type.getDirectory() + "/" + identifier.getNamespace() + "/" + identifier.getPath();
            DirRpo rpo = findDirRpo(pack, path);
            if (rpo != null && dirHidden(rpo, MetaCache.getKeyByPack(pack), path)) {
                path = findReplacementDir(path, rpo);
                if (path != null && dirFilterAdditive) {
                    String[] s = path.split("/", 3);
                    if (s.length == 3) {
                        ResourcePath rp = new ResourcePath(path);
                        //TODO improve this impl (used for files that aren't at the original location
                        pack.findResources(rp.getType(), rp.getId().getNamespace(), rp.getId().getPath(), (resource, resVal) -> {
                            String p = type.getDirectory() + "/" + resource.getNamespace() + "/" + resource.getPath();
                            p = p.replace(rpo.fallback, rpo.path + "/");
                            previous.accept(new ResourcePath(p).getId(), resVal);
                        });
                    }
                }
            } else previous.accept(identifier, value);
        };
    }

    private String findReplacementDir(String dir, DirRpo rpo) {
        if (rpo.fallback == null) return null;
        return dir.replace(rpo.path + "/", rpo.fallback);
    }

    private boolean dirHidden(DirRpo rpo, CacheKey key, String file) {
        if (rpo.condition == null)
            return false;
        try {
            return !rpo.condition.get(MetaCache.getParameter(key));
        } catch (Condition.ConditionException e) {
            String res = "Could not evaluate condition " + file + " (pack: " + key.packName() + ")";
            try {
                Respackopts.LOGGER.error(res + " with condition:\n" + ObjectGraphPrinter.printGraph(rpo.condition) + ")", e);
            } catch (Throwable ex) {
                Respackopts.LOGGER.error(res, e);
            }
        }
        return false;
    }

    private DirRpo findDirRpo(ResourcePack pack, String name) {
        CachedPackState state = MetaCache.getState(MetaCache.getKeyByPack(pack));
        Map<String, DirRpo> drpReg = state.cachedDirRPOs();
        int li = name.lastIndexOf('/');
        if (li <= 0)
            return null;
        name = name.substring(0, li);
        if (drpReg.containsKey(name)) return drpReg.get(name);
        DirRpo drp = findDirRpo(pack, name);
        if (drp != null) {
            drpReg.put(name, drp);
            return drp;
        }
        ResourcePath rp;
        try {
            rp = new ResourcePath(name + "/" + Respackopts.FILE_EXTENSION);
        }
        catch (Exception e) {
            return null;
        }
        InputSupplier<InputStream> is = UserResourceEvents.disable(() -> pack.open(rp.getType(), rp.getId()));
        if (is == null) return null;
        try (Reader w = new InputStreamReader(is.get())) {
            drp = AttachmentHolder.deserialize(state.metadata().version, w, DirRpo.class);
            drp.path = name;
            if (drp.fallback != null && !drp.fallback.endsWith("/"))
                drp.fallback += "/";
            drpReg.put(name, drp);
            return drp;
        } catch (IOException e) {
            Respackopts.LOGGER.error("Couldn't open dir rpo " + rp.getName(), e);
        }
        return null;
    }
}