package me.lethunderhawk.fluxapi.util.config;

import org.bukkit.configuration.ConfigurationSection;
import org.bukkit.configuration.file.YamlConfiguration;
import org.bukkit.configuration.serialization.ConfigurationSerializable;
import org.bukkit.plugin.java.JavaPlugin;

import java.io.File;
import java.io.IOException;
import java.util.*;
import java.util.function.Function;

public final class ConfigLoader {

    private final JavaPlugin plugin;
    private final File dataFolder;

    public ConfigLoader(JavaPlugin plugin) {
        this.plugin = plugin;
        this.dataFolder = plugin.getDataFolder();

        if (!dataFolder.exists()) {
            dataFolder.mkdirs();
        }
    }

    /* =========================================================
       =============== BASIC FILE HANDLING =====================
       ========================================================= */

    public File getFile(String path) {
        File file = new File(dataFolder, path.endsWith(".yml") ? path : path + ".yml");

        if (!file.getParentFile().exists()) {
            file.getParentFile().mkdirs();
        }

        return file;
    }

    /**
     * @Deprecated since 1.2.5
     * @param path
     * @return
     */
    public YamlConfiguration loadConfig(String path) {
        File file = getFile(path);
        return YamlConfiguration.loadConfiguration(file);
    }
    public YamlConfiguration safeLoadConfig(String path) {
        File file = getFile(path);

        if(!file.exists())
            return new YamlConfiguration();

        try {
            return YamlConfiguration.loadConfiguration(file);
        } catch(Exception e) {
            plugin.getLogger().warning("Failed to load config " + file.getName() + ", creating new one.");
            return new YamlConfiguration();
        }
    }

    public void saveConfig(YamlConfiguration cfg, String path) {
        File file = getFile(path);
        try {
            cfg.save(file);
        } catch (IOException e) {
            throw new RuntimeException("Could not save file: " + file.getName(), e);
        }
    }

    /* =========================================================
       =============== SINGLE OBJECT ============================
       ========================================================= */

    public <T extends ConfigurationSerializable> void saveObject(
            String path,
            String node,
            T object
    ) {
        YamlConfiguration cfg = safeLoadConfig(path);
        cfg.set(node, object);
        saveConfig(cfg, path);
    }

    public <T extends ConfigurationSerializable> T loadObject(
            String path,
            String node,
            Class<T> type
    ) {
        YamlConfiguration cfg = safeLoadConfig(path);

        Object obj = cfg.get(node);

        if(obj == null){
            System.out.println("Node '" + node + "' not found.");
            return null;
        }

        if (!type.isInstance(obj)) {
            throw new IllegalStateException(
                    "Expected type " + type.getName() +
                            " but got " + obj.getClass().getName()
            );
        }

        return type.cast(obj);
    }

    /* =========================================================
       =============== COLLECTION ===============================
       ========================================================= */

    public <T extends ConfigurationSerializable> void saveCollection(
            String path,
            String node,
            Collection<T> collection
    ) {
        YamlConfiguration cfg = safeLoadConfig(path);
        List<T> list = new ArrayList<>(collection);
        cfg.set(node, list);
        saveConfig(cfg, path);
    }

    public <T extends ConfigurationSerializable> List<T> loadCollection(
            String path,
            String node,
            Class<T> type
    ) {
        YamlConfiguration cfg = safeLoadConfig(path);

        List<?> rawList = cfg.getList(node);
        if (rawList == null) return new ArrayList<>();

        List<T> result = new ArrayList<>();

        for (Object obj : rawList) {
            if (type.isInstance(obj)) {
                result.add(type.cast(obj));
            }
        }

        return result;
    }

    /* =========================================================
       =============== MAP STORAGE ==============================
       ========================================================= */

    public <K, V extends ConfigurationSerializable> void saveMap(
            String path,
            String node,
            Map<K, V> map,
            Function<K, String> keySerializer
    ) {
        YamlConfiguration cfg = safeLoadConfig(path);

        ConfigurationSection section = cfg.createSection(node);

        for (Map.Entry<K, V> entry : map.entrySet()) {
            String key = keySerializer.apply(entry.getKey());
            section.set(key, entry.getValue());
        }

        saveConfig(cfg, path);
    }

    public <K, V extends ConfigurationSerializable> Map<K, V> loadMap(
            String path,
            String node,
            Function<String, K> keyDeserializer,
            Class<V> type
    ) {
        YamlConfiguration cfg = safeLoadConfig(path);

        ConfigurationSection section = cfg.getConfigurationSection(node);
        if (section == null) return new HashMap<>();

        Map<K, V> result = new HashMap<>();

        for (String key : section.getKeys(false)) {
            Object obj = section.get(key);

            if (type.isInstance(obj)) {
                result.put(
                        keyDeserializer.apply(key),
                        type.cast(obj)
                );
            }
        }

        return result;
    }
}