package luckyblock.configurations;

import com.google.gson.*;
import luckyblock.Main;
import luckyblock.action.LuckyActionHolder;

import java.io.*;
import java.lang.reflect.Field;
import java.nio.charset.StandardCharsets;
import java.util.Map;

public class Configuration {
    private final File file;
    private final Object impl;
    private final Gson gson = new GsonBuilder().setPrettyPrinting().create();

    public Configuration(File file, Object impl) {
        this.file = file;
        this.impl = impl;

        this.loadFromResources(this.impl);

        if (!file.exists()) {
            this.loadDefault();
        }
    }

    public Configuration(String path, Object impl) {
        this(new File(path), impl);
    }

    private void loadFromResources(Object r) {
        try (InputStream input = Main.class.getResourceAsStream("/settings.json")) {
            if (input == null) return;

            JsonObject root = JsonParser.parseReader(new InputStreamReader(input, StandardCharsets.UTF_8)).getAsJsonObject();
            this.model(r, root);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    protected void loadDefault() {
        try {
            file.getParentFile().mkdirs();
            JsonObject root = new JsonObject();
            String section = (String) this.impl.getClass().getField("section").get(this.impl);
            root.add(section, gson.toJsonTree(this.impl).getAsJsonObject().get("events"));

            try (FileWriter writer = new FileWriter(file)) {
                gson.toJson(root, writer);
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    public <T> T load() {
        try {
            if (!file.exists() || file.length() == 0) {
                this.loadDefault();
            }
            JsonObject root = JsonParser.parseReader(new FileReader(file)).getAsJsonObject();
            this.model(this.impl, root);
            return (T) this.impl;
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    @SuppressWarnings("unchecked")
    private void model(Object r, JsonObject root) throws Exception {
        String section = (String) r.getClass().getField("section").get(r);
        if (!root.has(section)) return;
        JsonObject sectionJson = root.getAsJsonObject(section);
        for (Field field : r.getClass().getDeclaredFields()) {
            if (field.getName().equals("section")) continue;
            field.setAccessible(true);
            if (Map.class.isAssignableFrom(field.getType())) {
                Map<String, LuckyActionHolder> eventsMap = (Map<String, LuckyActionHolder>) field.get(r);
                if (eventsMap != null) {
                    eventsMap.clear();
                    for (Map.Entry<String, JsonElement> entry : sectionJson.entrySet()) {
                        String k = entry.getKey().replace("-", "_");
                        LuckyActionHolder holder = gson.fromJson(entry.getValue(), LuckyActionHolder.class);
                        eventsMap.put(k, holder);
                    }
                }
            }
        }
    }
}