package shcm.shsupercm.fabric.citresewn.cit;

import net.fabricmc.loader.api.FabricLoader;
import net.minecraft.resource.ResourceManager;
import net.minecraft.util.profiler.Profiler;
import shcm.shsupercm.fabric.citresewn.api.CITDisposable;
import shcm.shsupercm.fabric.citresewn.api.CITTypeContainer;
import shcm.shsupercm.fabric.citresewn.config.CITResewnConfig;
import shcm.shsupercm.fabric.citresewn.pack.GlobalProperties;
import shcm.shsupercm.fabric.citresewn.pack.PackParser;
import shcm.shsupercm.fabric.citresewn.mixin.ModelLoaderMixin;

import java.util.*;

/**
 * Holds and manages the currently loaded CITs.
 * @see #getActive()
 * @see ModelLoaderMixin
 */
public class ActiveCITs { private ActiveCITs() {}
	/**
	 * @see #load(ResourceManager, Profiler)
	 * @see #getActive()
	 * @see #isActive()
	 */
    private static ActiveCITs active = null;

	/**
	 * @see #isActive()
	 * @return the current active CITs manager or null if none are loaded
	 */
    public static ActiveCITs getActive() {
        return active;
    }
	
	/**
	 * @see #getActive()
	 * @return whether there are active; loaded CITs
	 */
    public static boolean isActive() {
        return active != null;
    }

	/**
	 * Currently effective global properties merged from all loaded packs.
	 */
    public final GlobalProperties globalProperties = new GlobalProperties();

	/**
	 * All loaded CITs ordered by their type's class and their weight.
	 */
    public final Map<Class<? extends CITType>, List<CIT<?>>> cits = new IdentityHashMap<>();

	/**
	 * Attempts to load/activate CITs from packs in the given resource manager, disposing of any previously loaded CITs if present.
	 * @see ModelLoaderMixin
	 * @see PackParser#loadGlobalProperties(ResourceManager, GlobalProperties)
	 * @see GlobalProperties#callHandlers()
	 * @see PackParser#parseCITs(ResourceManager)
	 * @param resourceManager manager containing resourcepacks with possible CITs
	 * @param profiler loading profiler that was pushed once into "citresewn:reloading_cits" and would pop after
	 */
    public static void load(ResourceManager resourceManager, Profiler profiler) {
        profiler.push("citresewn:disposing");
        for (CITDisposable disposable : FabricLoader.getInstance().getEntrypoints(CITDisposable.ENTRYPOINT, CITDisposable.class))
            disposable.dispose();

        for (CITTypeContainer<? extends CITType> typeContainer : CITRegistry.TYPES.values())
            typeContainer.unload();

        if (active != null) {
            active.globalProperties.properties.replaceAll((key, value) -> Set.of());
            active.globalProperties.callHandlers();

            active = null;
        }

        if (!CITResewnConfig.INSTANCE.enabled) {
            profiler.pop();
            return;
        }

        ActiveCITs active = new ActiveCITs();

        profiler.swap("citresewn:load_global_properties");
        PackParser.loadGlobalProperties(resourceManager, active.globalProperties).callHandlers();

        profiler.swap("citresewn:load_cits");
        List<CIT<?>> cits = PackParser.parseCITs(resourceManager);
        for (CIT<?> cit : cits)
            active.cits.computeIfAbsent(cit.type.getClass(), type -> new ArrayList<>()).add(cit);
        for (Map.Entry<Class<? extends CITType>, List<CIT<?>>> entry : active.cits.entrySet()) {
            entry.getValue().sort(Comparator.<CIT<?>>comparingInt(cit -> cit.weight).reversed().thenComparing(cit -> cit.propertiesIdentifier.toString()));
            for (CITTypeContainer<? extends CITType> typeContainer : CITRegistry.TYPES.values())
                if (typeContainer.type == entry.getKey()) {
                    typeContainer.loadUntyped(entry.getValue());
                    break;
                }
        }

        profiler.pop();

        if (!cits.isEmpty())
            ActiveCITs.active = active;
    }
}