package com.bib.essensbestellungsverwaltung;
/*
    @author Malte Schulze Hobeling
 */

import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import java.security.NoSuchAlgorithmException;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.KeySpec;
import java.util.Base64;

public class AccountMgr {
    /**
     * creates a user with createUser(...) and adds its id to the 'worker' table
     * @param userData String[] name, firstname, password, email
     * @param addressData String[] street, number, plz, city
     * @return userid or -1
     */
    public static long createWorker(String[] userData, String[] addressData){
        long id = createUser(userData, addressData);
        String sId = String.valueOf(id);
        Database.insert("worker", new String[]{"userid"}, new String[]{sId});
        return id;
    }

    /**
     * creates a user with createUser(...) and adds its id to the 'parent' table
     * @param userData String[] name, firstname, password, email
     * @param addressData String[] street, number, plz, city
     * @return userid or -1
     */
    public static long createParent(String[] userData, String[] addressData){
        long id = createUser(userData, addressData);
        String sId = String.valueOf(id);
        Database.insert("parent", new String[]{"userid"}, new String[]{sId});
        return id;
    }

    /**
     * adds a user to the database
     * @param userData String[] name, firstname, password, email
     * @param addressData String[] street, number, plz, city
     * @return userid or -1
     */
    private static long createUser(String[] userData, String[] addressData) {
        String[] addressH = {"street", "number", "plz", "city"};
        String[] userH = {"name", "firstname", "addressid", "password", "email"};
        String name = userData[0];
        String firstname = userData[1];
        String pw = hashAndSalt(userData[2]);
        String email = userData[3];

        long id = Database.insert("address", addressH, addressData);
        String sId = String.valueOf(id);
        String[] userD = {name, firstname, sId, pw, email};
        id = Database.insert("user", userH, userD);
        return id;
    }

    public static long createChild(String[] childData,String[] allergyData, String[] severityData){
        String[] childH = {"name","firstname","addressid"};
        String[] child_allergyH = {"childid","allergyid","severityid"};
        long id = Database.insert("child", childH, childData);
        if(allergyData.length > 0){
            for(int i = 0; i < allergyData.length; i++){
                String sId = String.valueOf(id);
                String[] child_allergyD = {sId,allergyData[i],severityData[i]};
                Database.insert("child_allergy",child_allergyH,child_allergyD);
            }
        }
        return id;
    }

    public static long matchParentChild(String parentId, String childId){
        String[] parent_childH = {"parentuserid","childid"};
        String[] parent_childD = {parentId,childId};
        return Database.insert("parent_child", parent_childH,parent_childD);
    }

    public static long login(String email, String pw){
        String[] userH = {"email","password"};
        String[] userD = {email,hashAndSalt(pw)};
        return Database.getSingleId("user",userH,userD);
    }

    public static boolean isWorker(String id){
        String[] workerH = {"userid"};
        String[] workerD = {id};
        long workerId = Database.getSingleId("worker",workerH,workerD);
        return workerId > 0;
    }


    public static boolean isParent(String id){
        String[] parentH = {"userid"};
        String[] parentD = {id};
        long parentId = Database.getSingleId("parent",parentH,parentD);
        return parentId > 0;
    }

    public static String hashAndSalt(String pw){
        //todo: find a better way to salt
        byte[] magicSalt = new byte[]{96, 13, 100, 85, -37, 52, -123, 86, -123, -92, 16, 15, -110, -42, -49, 0};
        KeySpec spec = new PBEKeySpec(pw.toCharArray(), magicSalt,310001,256);
        String hashedPw;
        try {
            SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
            byte[] hash = factory.generateSecret(spec).getEncoded();
            Base64.Encoder enc = Base64.getEncoder();
            hashedPw = enc.encodeToString(hash);
        } catch (InvalidKeySpecException | NoSuchAlgorithmException e) {
            throw new RuntimeException(e);
        }
        return hashedPw;
    }
}