package me.dori_mon.json;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
import java.util.HashMap;
import java.util.Map;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonArray;
import com.google.gson.JsonElement;
import com.google.gson.JsonIOException;
import com.google.gson.JsonObject;
import com.google.gson.JsonSyntaxException;

public class JsonFile {

    private File file;
    private JsonObject json;
    private Map<String, JsonElement> defaults = new HashMap<>();
    Gson gson;

    /**
     * Creates a new JsonFile and sets it up (see {@link JsonFile#setup()}.
     * @param fileName the name of the file.
     */
    public JsonFile(final String fileName) {
        this("", fileName);
    }

    /**
     * Creates a new JsonFile and sets it up (see {@link JsonFile#setup()}.
     * @param path the path of the file.
     * @param fileName the name of the file.
     */
    public JsonFile(final String path, final String fileName) {
        this(path, fileName, new GsonBuilder().disableHtmlEscaping().setPrettyPrinting());
    }

    /**
     * Creates a new JsonFile and sets it up (see {@link JsonFile#setup()}.
     * @param path the path of the file.
     * @param fileName the name of the file.
     * @param gsonBuilder a gsonBuilder to use for formatting.
     */
    public JsonFile(final String path, final String fileName, final GsonBuilder gsonBuilder) {
        this.gson = gsonBuilder.create();
        if (!path.equals("")) {
            File pathFile = new File(path);
            if (!pathFile.exists())
                pathFile.mkdirs();
        }

        String finalFileName = new String(fileName);
        if (!fileName.endsWith(".json"))
            finalFileName = finalFileName + ".json";

        if (!path.equals(""))
            file = new File(path, finalFileName);
        else
            file = new File(finalFileName);

        if (!file.exists())
            try {
                file.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
                return;
            }
        setup();
    }

    /**
     * Saves the edited JsonObject to the File.
     */
    public void save() {
        try {
            Writer writer = new FileWriter(file);
            String parsedJson = gson.toJson(json);
            writer.write(parsedJson);
            writer.flush();
            writer.close();
        } catch (IOException e) {
            System.err.println("Could not save JsonFile named " + file.getName() + "!");
            e.printStackTrace();
            return;
        }
    }

    /**
     * Sets up the JsonFile, parses and handles defaults.
     */
    public void setup() {
        try {
            JsonElement element = gson.fromJson(new FileReader(file), JsonElement.class);
            if (element == null)
                json = new JsonObject();
            else
                json = element.getAsJsonObject();
        } catch (JsonSyntaxException | JsonIOException | FileNotFoundException e) {
            json = new JsonObject();
        }
        if (json == null)
            json = new JsonObject();
        copyDefaults();
    }

    /**
     * Sets a key to a value in the JsonFile.
     * @param key the key.
     * @param value the value.
     */
    public void set(String key, Object value) {
        if (containsKey(key))
            json.remove(key);
        json.add(key, gson.toJsonTree(value));
        save();
    }

    /**
     * Gets a Value as JsonElement from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public JsonElement get(String key) {
        return json.get(key);
    }

    /**
     * Gets a Value as String from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public String getAsString(String key) {
        return get(key).getAsString();
    }

    /**
     * Gets a Value as Boolean from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public boolean getAsBoolean(String key) {
        return get(key).getAsBoolean();
    }

    /**
     * Gets a Value as Integer from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public int getAsInt(String key) {
        return get(key).getAsInt();
    }

    /**
     * Gets a Value as Double from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public double getAsDouble(String key) {
        return get(key).getAsDouble();
    }

    /**
     * Gets a Value as Long from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public long getAsLong(String key) {
        return get(key).getAsLong();
    }

    /**
     * Gets a Value as JsonObject from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public JsonObject getAsJsonObject(String key) {
        return get(key).getAsJsonObject();
    }

    /**
     * Gets a Value as JsonArray from the JsonFile.
     * @param key the key.
     * @return the value.
     */
    public JsonArray getAsJsonArray(String key) {
        return get(key).getAsJsonArray();
    }

    /**
     * Checks if the file exists.
     * @return true if it exists, false if not.
     */
    public boolean exists() {
        return file.exists();
    }

    /**
     * Checks if the JsonFile contains a key.
     * @param key the key.
     * @return true if it exists, false if not.
     */
    public boolean containsKey(String key) {
        return json.has(key);
    }

    /**
     * Adds a default to the defaults Map.
     * @param key the key of the default.
     * @param value the value of the default.
     */
    public void addDefault(String key, Object value) {
        defaults.put(key, gson.toJsonTree(value));
    }

    /**
     * Copies all defaults from the defaults Map to the JsonFile.
     */
    public void copyDefaults() {
        for (String key : defaults.keySet())
            if (!json.has(key))
                json.add(key, defaults.get(key));
        save();
    }

    /**
     * deletes the JsonFile.
     */
    public void delete() {
        file.delete();
    }

}