package com.multistorage;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;

import com.google.gson.Gson;
import com.google.gson.JsonIOException;
import com.google.gson.JsonSyntaxException;
import com.storage.Article;

public class StorageSystem
{

    private static final String STORAGE_FILE_TYPE = ".json";
    private static final String STORAGE_FILE_NAME_PREFIX = "storage";
    private static final int STORAGE_FILE_SPLIT_SIZE = 100000;
    private final String PATH_TO_LINK_FILE = "src/com/multistorage/visitedlinks.txt";
    private final String PATH_TO_STORAGE_FOLDER;
    private int amountFilesInFolder;
    private int currentFileSize;
    private File latestFile;
    private Gson gson;
    private FileReader fr;
    private FileWriter jsonWriter;
    private FileWriter linkWriter;


    public StorageSystem(String PATH_TO_STORAGE_FOLDER)
    {
        this.PATH_TO_STORAGE_FOLDER = PATH_TO_STORAGE_FOLDER;
        this.amountFilesInFolder = getAmountFilesInFolder();
        this.gson = new Gson();


    }

    public void store(Article article, String linkToCheck) throws IOException
    {

        this.amountFilesInFolder = getAmountFilesInFolder();
        if(amountFilesInFolder == 0)
        {
            latestFile = new File(PATH_TO_STORAGE_FOLDER + "\\" + STORAGE_FILE_NAME_PREFIX + amountFilesInFolder + STORAGE_FILE_TYPE);
            System.out.println(latestFile.getAbsolutePath());
            //System.out.println(latestFile.getPath());
            try
            {
                latestFile.createNewFile();
            } catch (IOException e)
            {
                e.printStackTrace();
            }

        }
        latestFile = getLatestFile();
        jsonWriter = new FileWriter(latestFile);
        linkWriter = new FileWriter(PATH_TO_LINK_FILE, true);





        Article[] contentOfFileArray = null;

        try
        {
            contentOfFileArray = gson.fromJson(new FileReader(latestFile), Article[].class);
        } catch (JsonSyntaxException | JsonIOException | FileNotFoundException e1)
        {
            e1.printStackTrace();
        }



        //System.out.println(contentOfFileArray.length);
        if(contentOfFileArray == null)
        {
            contentOfFileArray = new Article[0];
        }
        contentOfFileArray = getNewArticleArray(contentOfFileArray, article);
        if(latestFile.length() < STORAGE_FILE_SPLIT_SIZE)
        {


            if(isDuplicate(new File(PATH_TO_LINK_FILE), linkToCheck) == false)
            {

                try
                {
                    System.out.println(linkToCheck);
                    System.out.println(latestFile.getPath());
                    jsonWriter.write(gson.toJson(contentOfFileArray));
                    jsonWriter.flush();
                    int hashcode = linkToCheck.hashCode();
                    linkWriter.write(hashcode + "\n");
                    linkWriter.flush();

                } catch (Exception e)
                {

                }
            }
        } else
        {

            System.out.println("Datei ist zu groß. Neue Datei wird erstellt.");
        }








    }

    public int getAmountFilesInFolder()
    {
        return new File(PATH_TO_STORAGE_FOLDER).list().length;
    }

    public File getLatestFile()
    {

        File[] fileArray = new File(PATH_TO_STORAGE_FOLDER).listFiles();

        return fileArray[fileArray.length - 1];
    }

    public Article[] getNewArticleArray(Article[] oldArray, Article article)
    {
        Article[] oldArrayCopy = new Article[oldArray.length + 1];
        for(int i = 0; i < oldArray.length - 1; i++)
        {
            oldArrayCopy[i] = oldArray[i];
        }
        oldArrayCopy[oldArrayCopy.length - 1] = article;

        return oldArrayCopy;
    }

    public boolean isDuplicate(File linkFile, String link) throws IOException
    {
        Scanner scan = new Scanner(linkFile);

        int hashWert = link.hashCode();


        while(scan.hasNextLine())
        {

            String line = scan.nextLine();
            int lineWert = Integer.parseInt(line);

            if(lineWert == hashWert)
            {
                return true;
            }
        }
        return false;
    }

}