package gitlet;
import java.io.File;
import static gitlet.Utils.*;
import java.io.Serializable;
import java.util.HashMap;

// TODO: any imports you need here

/** Represents a gitlet repository.
 *  TODO: It's a good idea to give a description here of what else this Class
 *  does at a high level.
 *
 *  @author TODO
 */
public class Repository implements Serializable {
    /**
     * TODO: add instance variables here.
     *
     * List all instance variables of the Repository class here with a useful
     * comment above them describing what that variable represents and how that
     * variable is used. We've provided two examples for you.
     */

    /** The current working directory. */
    public static final File CWD = new File(System.getProperty("user.dir"));
    /** The .gitlet directory. */
    public static final File GITLET_DIR = join(CWD, ".gitlet");

    /* TODO: fill in the rest of this class. */
    public static String HEAD;
    public static String MASTER;
    private File blob;
    public static final File staged = Utils.join(GITLET_DIR, "staged");;

    private File commit;



    public static final File Head = Utils.join(GITLET_DIR, "Head");

    public static final File Master = Utils.join(GITLET_DIR, "Master");

    public static final File stagedForRemoval = Utils.join(staged, "stagedForRemoval");

    public static final File stagedForAddition = Utils.join(staged, "stagedForAddition");

    public static final HashMap<String, String> addFiles = new HashMap();
    //filename -- sha1

    public static final HashMap<String, String> blobs = new HashMap<String, String>();
    //blobname -- sha1



    public void init(){
        if (GITLET_DIR.exists()){
            System.out.println("A Gitlet version-control system already exists in the current directory.");
            return;
        }

        GITLET_DIR.mkdir();


        staged.mkdir();

        stagedForRemoval.mkdir();


        stagedForAddition.mkdir();

        blob = Utils.join(GITLET_DIR, "blob");

        blob.mkdir();

        blob = Utils.join(GITLET_DIR, "blob");

        blob.mkdir();

        commit = Utils.join(GITLET_DIR, "commit");

        commit.mkdir();

        //head file point to current branch

        Commit init = new Commit("initial commit", null, null);
        MASTER = Utils.sha1(Utils.serialize(init));
        String sha1 = Utils.sha1(Utils.serialize(init));
        Utils.writeContents(Head, sha1);
        Utils.writeContents(Master, sha1);
    }


    //check if commit exists of same added file

    //check added file is already in commits & and check if they are identical
    //sha1 head commit
    //check if file name checks in commit
    //if file exists -- see if file is identical in CWD

    //compare cwd file sha1 to sha1 of commit
    //make sure most recent comment

    public void add(File FileName) {
        //check if file even exists
       if (!FileName.exists()){
           throw new IllegalArgumentException("File does not exist.");
       }
       //sha1 of CWD file
        String sha1first = sha1(Utils.readContents(FileName));
       //create commit object of most current commit
       Commit commitobj = Utils.readObject(Utils.join(commit, HEAD), Commit.class);
       //get sha1 of blob
        String sha1second = commitobj.getblob(FileName.toString());
        //check if the commit blob sha1 is same as CWD file (aka the contents)
        if (sha1second.equals(sha1first)) {
            throw new IllegalArgumentException("No changes have been made to the file.");
        }
        //sha1 of added file if it already exists
       String temp = addFiles.get(FileName);
        //sha1 of added most recent added version
       addFiles.put(FileName.toString(),  sha1(FileName));
       String temp2 = addFiles.get(FileName);
       //check if the files are not equal -- so we know to writeContent (Serialze)
       if (!temp.equals(temp2)) {
           addFiles.remove(temp);
           FileName = Utils.join(stagedForAddition, temp2);
           //get contents of file
           byte[] contents = Utils.serialize(FileName);
           //write contents into file
           Utils.writeContents(FileName, contents);
       }
    }





}