prototype/src/main/java/org/hso/ecommerce/action/cronjob/ReadSupplierDataAction.java

@@ -0,0 +1,83 @@
+package org.hso.ecommerce.action.cronjob;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Objects;
+
+import org.hso.ecommerce.api.SupplierService;
+import org.hso.ecommerce.api.data.Article;
+import org.hso.ecommerce.api.data.Supplier;
+
+public class ReadSupplierDataAction {
+    private List<org.hso.ecommerce.entities.supplier.Supplier> suppliers;
+
+    public static class ArticleIdentifier {
+        public final String manufacturer;
+        public final String articleNumber;
+
+        public ArticleIdentifier(String manufacturer, String articleNumber) {
+            this.manufacturer = manufacturer;
+            this.articleNumber = articleNumber;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(manufacturer, articleNumber);
+        }
+
+        @Override
+        public boolean equals(Object other) {
+            if (!(other instanceof ArticleIdentifier)) {
+                return false;
+            }
+            ArticleIdentifier otherId = (ArticleIdentifier) other;
+            return this.manufacturer.equals(otherId.manufacturer) && this.articleNumber.equals(otherId.articleNumber);
+        }
+    }
+
+    public ReadSupplierDataAction(List<org.hso.ecommerce.entities.supplier.Supplier> suppliers) {
+        this.suppliers = suppliers;
+    }
+
+    public static class Offer {
+        public final org.hso.ecommerce.entities.supplier.Supplier dbSupplier;
+        public final Supplier apiSupplier;
+
+        public Offer(org.hso.ecommerce.entities.supplier.Supplier dbSupplier, Supplier apiSupplier) {
+            this.dbSupplier = dbSupplier;
+            this.apiSupplier = apiSupplier;
+        }
+    }
+
+    public static class Result {
+        public final ArrayList<Supplier> supplierData;
+        public final HashMap<ArticleIdentifier, Offer> cheapestOffer;
+
+        public Result(ArrayList<Supplier> supplierData, HashMap<ArticleIdentifier, Offer> cheapestOffer) {
+            this.supplierData = supplierData;
+            this.cheapestOffer = cheapestOffer;
+        }
+    }
+
+    public Result finish() {
+        ArrayList<Supplier> suppliers = new ArrayList<>();
+        HashMap<ArticleIdentifier, Integer> price = new HashMap<>();
+        HashMap<ArticleIdentifier, Offer> cheapest = new HashMap<>();
+        for (org.hso.ecommerce.entities.supplier.Supplier supplier : this.suppliers) {
+            SupplierService service = new SupplierService(supplier.apiUrl);
+            Supplier apiSupplier = service.getSupplier();
+            suppliers.add(apiSupplier);
+            for (Article article : apiSupplier.articles) {
+                ArticleIdentifier identifier = new ArticleIdentifier(article.manufacturer, article.articleNumber);
+                Integer previousPrice = price.get(identifier);
+                if (previousPrice == null || article.pricePerUnitNet < previousPrice) {
+                    price.put(identifier, article.pricePerUnitNet);
+                    cheapest.put(identifier, new Offer(supplier, apiSupplier));
+                }
+            }
+        }
+
+        return new Result(suppliers, cheapest);
+    }
+}

prototype/src/main/java/org/hso/ecommerce/action/cronjob/ReorderAction.java

@@ -0,0 +1,107 @@
+package org.hso.ecommerce.action.cronjob;
+
+import java.sql.Timestamp;
+import java.util.HashMap;
+
+import org.hso.ecommerce.action.cronjob.ReadSupplierDataAction.ArticleIdentifier;
+import org.hso.ecommerce.action.cronjob.ReadSupplierDataAction.Offer;
+import org.hso.ecommerce.api.SupplierService;
+import org.hso.ecommerce.api.data.Order;
+import org.hso.ecommerce.api.data.OrderConfirmation;
+import org.hso.ecommerce.entities.shop.Article;
+import org.hso.ecommerce.entities.supplier.ArticleOffer;
+import org.hso.ecommerce.entities.supplier.SupplierOrder;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class ReorderAction {
+    private static final Logger log = LoggerFactory.getLogger(ReorderAction.class);
+
+    private Article article;
+    private Integer[] orderedAmounts;
+    private Integer undeliveredReorders;
+    private int amountInStock;
+    private HashMap<ArticleIdentifier, Offer> cheapestOffer;
+    private HashMap<ArticleIdentifier, ArticleOffer> articleOffers;
+
+    public ReorderAction(
+            Article article, Integer[] orderedAmounts,
+            Integer undeliveredReorders,
+            int amountInStock,
+            HashMap<ArticleIdentifier, Offer> cheapestOffer,
+            HashMap<ArticleIdentifier, ArticleOffer> articleOffers
+    ) {
+        this.article = article;
+        this.orderedAmounts = orderedAmounts;
+        this.undeliveredReorders = undeliveredReorders;
+        this.amountInStock = amountInStock;
+        this.cheapestOffer = cheapestOffer;
+        this.articleOffers = articleOffers;
+    }
+
+    private int null_to_zero(Integer input) {
+        return input == null ? 0 : input;
+    }
+
+    private int calculateAmountToReorder() {
+        // Algorithm as described in the documentation
+        int a = null_to_zero(orderedAmounts[0]);
+        int b = null_to_zero(orderedAmounts[1]);
+        int c = null_to_zero(orderedAmounts[2]);
+
+        int x = Math.max(Math.max(a, b), c);
+        int y = Math.min(Math.min(a, b), c);
+
+        int n = 6 * x - 2 * y;
+        if (n < 3) {
+            n = 3;
+        }
+
+        int i = null_to_zero(undeliveredReorders);
+        int l = amountInStock;
+
+        return n - i - l;
+    }
+
+    public SupplierOrder finish() {
+        if (!article.shouldReorder) {
+            return null;
+        }
+
+        int amount = calculateAmountToReorder();
+        if (amount <= 0) {
+            return null;
+        }
+
+        ArticleIdentifier identifier = new ArticleIdentifier(article.related.manufacturer, article.related.articleNumber);
+        Offer offer = cheapestOffer.get(identifier);
+        if (offer == null) {
+            log.info("Could not order \"" + article.title + "\" because there is no supplier delivering it.");
+            return null;
+        }
+
+        ArticleOffer articleOffer = articleOffers.get(identifier);
+        org.hso.ecommerce.api.data.Article apiArticle = offer.apiSupplier.findArticle(identifier.manufacturer,
+                identifier.articleNumber);
+        if (apiArticle.pricePerUnitNet > article.reorderMaxPrice) {
+            log.info("Could not order \"" + article.title + "\" because it is currently too expensive.");
+            return null;
+        }
+
+        Order order = new Order();
+        order.manufacturer = articleOffer.manufacturer;
+        order.articleNumber = articleOffer.articleNumber;
+        order.quantity = amount;
+        order.maxTotalPriceCentNet = apiArticle.pricePerUnitNet * amount;
+
+        OrderConfirmation confirm = new SupplierService(offer.dbSupplier.apiUrl).order(order);
+        SupplierOrder createdOrder = new SupplierOrder();
+        createdOrder.created = new Timestamp(System.currentTimeMillis());
+        createdOrder.supplier = offer.dbSupplier;
+        createdOrder.ordered = articleOffer;
+        createdOrder.numberOfUnits = confirm.quantity;
+        createdOrder.pricePerUnitNetCent = confirm.pricePerUnitNetCent;
+        createdOrder.totalPriceNet = confirm.totalPriceNetCharged;
+        return createdOrder;
+    }
+}

prototype/src/main/java/org/hso/ecommerce/action/cronjob/UpdateOffersAction.java

@@ -0,0 +1,59 @@
+package org.hso.ecommerce.action.cronjob;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map.Entry;
+
+import org.hso.ecommerce.action.cronjob.ReadSupplierDataAction.ArticleIdentifier;
+import org.hso.ecommerce.action.cronjob.ReadSupplierDataAction.Offer;
+import org.hso.ecommerce.api.data.Article;
+import org.hso.ecommerce.entities.supplier.ArticleOffer;
+
+public class UpdateOffersAction {
+    private List<ArticleOffer> offers;
+    private HashMap<ArticleIdentifier, Offer> cheapestOffer;
+
+    public UpdateOffersAction(List<ArticleOffer> offers, HashMap<ArticleIdentifier, Offer> cheapestOffer) {
+        this.offers = offers;
+        this.cheapestOffer = cheapestOffer;
+    }
+
+    private HashMap<ArticleIdentifier, ArticleOffer> mapOffers() {
+        HashMap<ArticleIdentifier, ArticleOffer> map = new HashMap<>();
+        for (ArticleOffer offer : offers) {
+            ArticleIdentifier identifier = new ArticleIdentifier(offer.manufacturer, offer.articleNumber);
+            map.put(identifier, offer);
+        }
+        return map;
+    }
+
+    public List<ArticleOffer> finish() {
+        HashMap<ArticleIdentifier, ArticleOffer> availableOffers = mapOffers();
+
+        // Reset all advertise-flags first. They are set again below.
+        for (ArticleOffer offer : availableOffers.values()) {
+            offer.shouldBeAdvertised = false;
+        }
+
+        for (Entry<ArticleIdentifier, Offer> cheapestOffer : cheapestOffer.entrySet()) {
+            String manufacturer = cheapestOffer.getKey().manufacturer;
+            String articleNumber = cheapestOffer.getKey().articleNumber;
+            ArticleOffer currentOffer = availableOffers.get(cheapestOffer.getKey());
+            if (currentOffer == null) {
+                currentOffer = new ArticleOffer();
+                currentOffer.manufacturer = manufacturer;
+                currentOffer.articleNumber = articleNumber;
+                offers.add(currentOffer);
+            }
+            Article currentOfferedArticle = cheapestOffer.getValue().apiSupplier.findArticle(manufacturer,
+                    articleNumber);
+            currentOffer.vatPercent = currentOfferedArticle.vatPercent;
+
+            // Set advertise-flag if any supplier wants it to be set
+            if (currentOfferedArticle.shouldBeAdvertised) {
+                currentOffer.shouldBeAdvertised = true;
+            }
+        }
+        return offers;
+    }
+}

prototype/src/main/java/org/hso/ecommerce/api/SupplierService.java

@@ -0,0 +1,27 @@
+package org.hso.ecommerce.api;
+
+import org.hso.ecommerce.api.data.Order;
+import org.hso.ecommerce.api.data.OrderConfirmation;
+import org.hso.ecommerce.api.data.Supplier;
+import org.springframework.web.client.RestTemplate;
+
+public class SupplierService {
+
+    private final String url;
+
+    public SupplierService(String url) {
+        this.url = url;
+    }
+
+    public Supplier getSupplier() {
+        RestTemplate restTemplate = new RestTemplate();
+
+        return restTemplate.getForObject(url, Supplier.class);
+    }
+
+    public OrderConfirmation order(Order order) {
+        RestTemplate restTemplate = new RestTemplate();
+
+        return restTemplate.postForObject(url + "/order", order, OrderConfirmation.class);
+    }
+}

prototype/src/main/java/org/hso/ecommerce/api/data/Article.java

@@ -0,0 +1,11 @@
+package org.hso.ecommerce.api.data;
+
+public class Article {
+    public String title;
+    public String manufacturer;
+    public String articleNumber;
+
+    public int vatPercent;
+    public int pricePerUnitNet;
+    public boolean shouldBeAdvertised;
+}

prototype/src/main/java/org/hso/ecommerce/api/data/Order.java

@@ -0,0 +1,9 @@
+package org.hso.ecommerce.api.data;
+
+public class Order {
+    public String manufacturer;
+    public String articleNumber;
+
+    public int quantity;
+    public int maxTotalPriceCentNet;
+}

prototype/src/main/java/org/hso/ecommerce/api/data/OrderConfirmation.java

@@ -0,0 +1,12 @@
+package org.hso.ecommerce.api.data;
+
+public class OrderConfirmation {
+    public String manufacturer;
+    public String articleNumber;
+
+    public int quantity;
+
+    public int pricePerUnitNetCent;
+    public int discountNetCent;
+    public int totalPriceNetCharged;
+}

prototype/src/main/java/org/hso/ecommerce/api/data/Supplier.java

@@ -0,0 +1,21 @@
+package org.hso.ecommerce.api.data;
+
+import java.util.List;
+
+public class Supplier {
+
+    public String id;
+    public String name;
+    public SupplierDiscount discount;
+    public List<Article> articles;
+
+    public Article findArticle(String manufacturer, String articleNumber) {
+        for (Article a : articles) {
+            if (a.manufacturer.equals(manufacturer) && a.articleNumber.equals(articleNumber)) {
+                return a;
+            }
+        }
+
+        return null;
+    }
+}

prototype/src/main/java/org/hso/ecommerce/api/data/SupplierDiscount.java

@@ -0,0 +1,6 @@
+package org.hso.ecommerce.api.data;
+
+public class SupplierDiscount {
+    public int minimumDailySalesVolumeNetCent;
+    public int percentDiscount;
+}

prototype/src/main/java/org/hso/ecommerce/controller/cronjob/CronjobController.java

@@ -0,0 +1,331 @@
+package org.hso.ecommerce.controller.cronjob;
+
+import java.sql.Timestamp;
+import java.util.Calendar;
+import java.util.Collections;
+import java.util.GregorianCalendar;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import javax.annotation.PostConstruct;
+
+import org.hso.ecommerce.action.booking.CreateBookingAction;
+import org.hso.ecommerce.action.cronjob.ReadSupplierDataAction;
+import org.hso.ecommerce.action.cronjob.ReadSupplierDataAction.ArticleIdentifier;
+import org.hso.ecommerce.action.cronjob.ReorderAction;
+import org.hso.ecommerce.action.cronjob.UpdateOffersAction;
+import org.hso.ecommerce.entities.booking.Booking;
+import org.hso.ecommerce.entities.booking.BookingAccountEntry;
+import org.hso.ecommerce.entities.booking.BookingReason;
+import org.hso.ecommerce.entities.cron.BackgroundJob;
+import org.hso.ecommerce.entities.shop.Article;
+import org.hso.ecommerce.entities.supplier.ArticleOffer;
+import org.hso.ecommerce.entities.supplier.Supplier;
+import org.hso.ecommerce.entities.supplier.SupplierOrder;
+import org.hso.ecommerce.repos.booking.BookingAccountEntryRepository;
+import org.hso.ecommerce.repos.booking.BookingRepository;
+import org.hso.ecommerce.repos.cronjob.BackgroundJobRepository;
+import org.hso.ecommerce.repos.shop.ArticleRepository;
+import org.hso.ecommerce.repos.shop.CustomerOderRepository;
+import org.hso.ecommerce.repos.supplier.ArticleOfferRepository;
+import org.hso.ecommerce.repos.supplier.SupplierOrderRepository;
+import org.hso.ecommerce.repos.supplier.SupplierRepository;
+import org.hso.ecommerce.repos.warehouse.WarehouseBookingPositionSlotEntryRepository;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+interface ICronjob {
+    /**
+     * Calculate the earliest cronjob execution time that happens after the given reference time.
+     *
+     * @param reference Position in time to start searching. The implementor is allowed to modify the reference time.
+     * @return A new Calendar instance (or the same) containing the time for next execution.
+     */
+    Calendar nextExecution(Calendar reference);
+
+    /**
+     * Calculate the latest cronjob execution time that happens before or exactly at the given refernce time.
+     *
+     * @param reference Position in time to start searching. The implementor is allowed to modify the reference time.
+     * @return A new Calendar instance (or the same) containing the time of the last execution.
+     */
+    Calendar previousExecution(Calendar reference);
+
+    /**
+     * Execute this cronjob.
+     *
+     * @param time       The point in time this execution was scheduled. In case of a missed cronjob, the actual time of
+     *                   this call might be much later.
+     * @param controller Back-reference that allows to use repositories.
+     */
+    void executeAt(Calendar time, CronjobController controller);
+}
+
+@Component
+class Reorder implements ICronjob {
+    @Override
+    public Calendar nextExecution(Calendar reference) {
+        if (reference.get(Calendar.HOUR_OF_DAY) >= 8) {
+            reference.add(Calendar.DAY_OF_MONTH, 1);
+        }
+        reference.set(Calendar.HOUR_OF_DAY, 8);
+        reference.set(Calendar.MINUTE, 0);
+        reference.set(Calendar.SECOND, 0);
+        reference.set(Calendar.MILLISECOND, 0);
+        return reference;
+    }
+
+    @Override
+    public Calendar previousExecution(Calendar reference) {
+        if (reference.get(Calendar.HOUR_OF_DAY) < 8) {
+            reference.add(Calendar.DAY_OF_MONTH, -1);
+        }
+        reference.set(Calendar.HOUR_OF_DAY, 8);
+        reference.set(Calendar.MINUTE, 0);
+        reference.set(Calendar.SECOND, 0);
+        reference.set(Calendar.MILLISECOND, 0);
+        return reference;
+    }
+
+    /**
+     * Calculates the amount of ordered articles by customers for the given article type in the time between begin and
+     * end.
+     *
+     * @param article The article to search orders for.
+     * @param begin   The start time for the search (included)
+     * @param end     The end time for the search (excluded)
+     * @return The number of articles that were ordered by customers in the given range.
+     */
+    private Integer getOrderedAmounts(Article article, Calendar begin, Calendar end, CronjobController controller) {
+        return controller.customerOrderRepository.countOrdersOfArticleInTimespan(
+                article.id,
+                new Timestamp(begin.getTimeInMillis()), new Timestamp(end.getTimeInMillis()));
+    }
+
+    /**
+     * Calculates the amount of ordered articles by customers for the given article type in the three days before the
+     * given reference time. The return-array contains 3 fields: Index 0: Orders 72 to 48 hours ago; Index 1: Orders 48
+     * to 24 hours ago; Index 2: Orders 24 to 0 hours ago.
+     *
+     * @param article The article for which the customer orders are checked.
+     * @param time    The reference time to use for calculation of the last orders.
+     * @return A 3-element array containing the orders of the last three days.
+     */
+    private Integer[] getOrderedAmounts(Article article, Calendar time, CronjobController controller) {
+        Calendar oneDayBefore = (Calendar) time.clone();
+        oneDayBefore.add(Calendar.DAY_OF_MONTH, -1);
+        Calendar twoDaysBefore = (Calendar) time.clone();
+        twoDaysBefore.add(Calendar.DAY_OF_MONTH, -2);
+        Calendar threeDaysBefore = (Calendar) time.clone();
+        threeDaysBefore.add(Calendar.DAY_OF_MONTH, -3);
+
+        return new Integer[] { //
+                getOrderedAmounts(article, threeDaysBefore, twoDaysBefore, controller), //
+                getOrderedAmounts(article, twoDaysBefore, oneDayBefore, controller), //
+                getOrderedAmounts(article, oneDayBefore, time, controller), //
+        };
+    }
+
+    private HashMap<ArticleIdentifier, ArticleOffer> mapArticleOffers(List<ArticleOffer> articleOffers) {
+        HashMap<ArticleIdentifier, ArticleOffer> map = new HashMap<>();
+        for (ArticleOffer articleOffer : articleOffers) {
+            ArticleIdentifier identifier = new ArticleIdentifier(articleOffer.manufacturer, articleOffer.articleNumber);
+            map.put(identifier, articleOffer);
+        }
+        return map;
+    }
+
+    @Override
+    public void executeAt(Calendar time, CronjobController controller) {
+        List<Supplier> suppliers = controller.supplierRepository.findAll();
+        ReadSupplierDataAction.Result supplierData = new ReadSupplierDataAction(suppliers).finish();
+
+        // Save the new offers in the database
+        List<ArticleOffer> allOffers = controller.articleOfferRepository.findAll();
+        allOffers = new UpdateOffersAction(allOffers, supplierData.cheapestOffer).finish();
+        controller.articleOfferRepository.saveAll(allOffers);
+
+        HashMap<ArticleIdentifier, ArticleOffer> mappedOffers = mapArticleOffers(allOffers);
+
+        // Reorder
+        List<Article> allArticles = controller.articleRepository.findAll();
+        for (Article article : allArticles) {
+            Integer[] orderedAmounts = getOrderedAmounts(article, time, controller);
+
+            Integer undeliveredReorders = controller.supplierOrderRepository
+                    .countUndeliveredReorders(article.related.articleNumber);
+
+            int amountInStock = controller.warehouseBookingPositionSlotEntryRepository.getArticleStock(article.id)
+                    .orElse(0);
+
+            ReorderAction action = new ReorderAction(article, orderedAmounts,
+                    undeliveredReorders,
+                    amountInStock,
+                    supplierData.cheapestOffer, mappedOffers);
+            SupplierOrder order = action.finish();
+            if (order != null) {
+                controller.supplierOrderRepository.save(order);
+
+                // Create bookings for this order
+                int netPrice = order.totalPriceNet;
+                int vatPercent = order.ordered.vatPercent;
+                int vatAmount = netPrice * vatPercent / 100;
+                int grossPrice = netPrice + vatAmount;
+
+                // Obligation towards the supplier
+                BookingAccountEntry mainAccount = controller.bookingAccountEntryRepository.getByMain()
+                        .orElseGet(BookingAccountEntry::newMain);
+                BookingAccountEntry supplierAccount = controller.bookingAccountEntryRepository
+                        .getBySupplier(order.supplier.id)
+                        .orElseGet(() -> BookingAccountEntry.newSupplier(order.supplier));
+                BookingReason obligationReason = new BookingReason(order);
+                Booking obligationBooking = new CreateBookingAction(mainAccount,
+                        supplierAccount,
+                        obligationReason,
+                        grossPrice).finish();
+                controller.bookingRepository.save(obligationBooking);
+
+                // Input Tax
+                BookingAccountEntry vatAccount = controller.bookingAccountEntryRepository.getByVat()
+                        .orElseGet(BookingAccountEntry::newVat);
+                mainAccount = controller.bookingAccountEntryRepository.getByMain().get();
+                BookingReason inputTaxReason = new BookingReason(order);
+                Booking inputTaxBooking = new CreateBookingAction(vatAccount, mainAccount, inputTaxReason, vatAmount)
+                        .finish();
+                controller.bookingRepository.save(inputTaxBooking);
+            }
+        }
+    }
+}
+
+class ScheduledCronjob {
+    public final Calendar executionTime;
+    public final ICronjob cronjob;
+    public final BackgroundJob model;
+
+    public ScheduledCronjob(Calendar executionTime, ICronjob cronjob, BackgroundJob model) {
+        this.executionTime = executionTime;
+        this.cronjob = cronjob;
+        this.model = model;
+    }
+}
+
+@Component
+class CronjobController {
+    private static final Logger log = LoggerFactory.getLogger(CronjobController.class);
+
+    private static final Map<String, ICronjob> cronjobs = getCronjobs();
+
+    @Autowired
+    private final BackgroundJobRepository cronjobRepository = null;
+
+    @Autowired
+    final ArticleRepository articleRepository = null;
+
+    @Autowired
+    final ArticleOfferRepository articleOfferRepository = null;
+
+    @Autowired
+    final CustomerOderRepository customerOrderRepository = null;
+
+    @Autowired
+    final BookingRepository bookingRepository = null;
+
+    @Autowired
+    final BookingAccountEntryRepository bookingAccountEntryRepository = null;
+
+    @Autowired
+    final WarehouseBookingPositionSlotEntryRepository warehouseBookingPositionSlotEntryRepository = null;
+
+    @Autowired
+    final SupplierRepository supplierRepository = null;
+
+    @Autowired
+    final SupplierOrderRepository supplierOrderRepository = null;
+
+    private static Map<String, ICronjob> getCronjobs() {
+        HashMap<String, ICronjob> map = new HashMap<>();
+
+        // Register all existing cronjobs
+        map.put(BackgroundJob.JOB_REORDER, new Reorder());
+
+        return Collections.unmodifiableMap(map);
+    }
+
+    private ScheduledCronjob getNextCronjob() {
+        Calendar currentTime = new GregorianCalendar();
+        Iterable<BackgroundJob> jobs = cronjobRepository.findAll();
+        HashMap<String, BackgroundJob> alreadyExecuted = new HashMap<>();
+        for (BackgroundJob job : jobs) {
+            alreadyExecuted.put(job.jobName, job);
+        }
+        ScheduledCronjob earliestJob = null;
+        for (Entry<String, ICronjob> entry : cronjobs.entrySet()) {
+            ScheduledCronjob resultingJob;
+            BackgroundJob dbEntry = alreadyExecuted.get(entry.getKey());
+            if (dbEntry != null) {
+                Calendar previousExecution = new GregorianCalendar();
+                previousExecution.setTimeInMillis(dbEntry.lastExecution.getTime());
+                Calendar followingSchedule = entry.getValue().nextExecution((Calendar) previousExecution.clone());
+                Calendar lastSchedule = entry.getValue().previousExecution((Calendar) currentTime.clone());
+                if (lastSchedule.getTimeInMillis() > followingSchedule.getTimeInMillis()) {
+                    // This happens, if more than one execution was missed.
+                    // In this case, run the job only once.
+                    followingSchedule = lastSchedule;
+                }
+                resultingJob = new ScheduledCronjob(followingSchedule, entry.getValue(), dbEntry);
+            } else {
+                // This cronjob has never been executed before.
+                Calendar lastScheduleTime = entry.getValue().previousExecution((Calendar) currentTime.clone());
+                BackgroundJob model = new BackgroundJob();
+                model.jobName = entry.getKey();
+                resultingJob = new ScheduledCronjob(lastScheduleTime, entry.getValue(), model);
+            }
+
+            // Look for the job with earliest executionTime - it will run next
+            if (earliestJob == null
+                    || resultingJob.executionTime.getTimeInMillis() < earliestJob.executionTime.getTimeInMillis()) {
+                earliestJob = resultingJob;
+            }
+        }
+        return earliestJob;
+    }
+
+    private void runCronjobExecutionLoop() {
+        Thread.currentThread().setName("Cronjob");
+        try {
+            while (true) {
+                ScheduledCronjob nextJob = getNextCronjob();
+                if (nextJob == null) {
+                    // In case there are no cronjobs
+                    return;
+                }
+                long waitingTime = nextJob.executionTime.getTimeInMillis() - System.currentTimeMillis();
+                if (waitingTime > 0) {
+                    Thread.sleep(waitingTime);
+                }
+
+                try {
+                    nextJob.cronjob.executeAt(nextJob.executionTime, this);
+                } catch (Throwable t) {
+                    log.error("Failed to execute cronjob " + nextJob.cronjob.getClass() + ":");
+                    t.printStackTrace();
+                }
+
+                nextJob.model.lastExecution = new Timestamp(nextJob.executionTime.getTimeInMillis());
+                cronjobRepository.save(nextJob.model);
+            }
+        } catch (InterruptedException e) {
+            log.error("The cronjob execution thread has been interrupted");
+        }
+    }
+
+    @PostConstruct
+    public void onPostConstruct() {
+        new Thread(this::runCronjobExecutionLoop).start();
+    }
+}

prototype/src/main/java/org/hso/ecommerce/entities/booking/BookingAccountEntry.java

@@ -16,10 +16,10 @@ public class BookingAccountEntry {
 
     public int newSumCent;
 
-    @ManyToOne(optional = true, cascade = CascadeType.ALL)
+    @ManyToOne(optional = true, cascade = CascadeType.MERGE)
     public User userAccount;
 
-    @ManyToOne(optional = true, cascade = CascadeType.ALL)
+    @ManyToOne(optional = true, cascade = CascadeType.MERGE)
     public Supplier supplierAccount;
 
     public boolean isMainAccount;
@@ -46,6 +46,14 @@ public class BookingAccountEntry {
         return e;
     }
 
+    public static BookingAccountEntry newSupplier(Supplier supplier) {
+        BookingAccountEntry e = new BookingAccountEntry();
+        e.supplierAccount = supplier;
+        e.newSumCent = 0;
+
+        return e;
+    }
+
     public static BookingAccountEntry newMain() {
         BookingAccountEntry e = new BookingAccountEntry();
         e.isMainAccount = true;

prototype/src/main/java/org/hso/ecommerce/entities/booking/BookingReason.java

@@ -39,4 +39,8 @@ public class BookingReason {
     public BookingReason(CustomerPayment customerPayment) {
         this.customerPayment = customerPayment;
     }
+
+    public BookingReason(SupplierOrder supplierOrder) {
+        this.supplierOrder = supplierOrder;
+    }
 }

prototype/src/main/java/org/hso/ecommerce/entities/cron/BackgroundJob.java

@@ -7,8 +7,8 @@ import javax.validation.constraints.NotNull;
 @Table(name = "background_jobs")
 public class BackgroundJob {
 
-    public final String JOB_DASHBOARD = "Dashboard";
-    public final String JOB_REORDER = "SupplierOrder";
+    public static final String JOB_DASHBOARD = "Dashboard";
+    public static final String JOB_REORDER = "SupplierOrder";
 
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)

prototype/src/main/java/org/hso/ecommerce/repos/booking/BookingAccountEntryRepository.java

@@ -1,18 +1,21 @@
 package org.hso.ecommerce.repos.booking;
 
+import java.util.Optional;
+
 import org.hso.ecommerce.entities.booking.BookingAccountEntry;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.stereotype.Repository;
 
-import java.util.Optional;
-
 @Repository
 public interface BookingAccountEntryRepository extends JpaRepository<BookingAccountEntry, Long> {
 
     @Query(value = "SELECT * FROM booking_account_entries as e WHERE e.user_account_id = :user ORDER BY e.id DESC LIMIT 1", nativeQuery = true)
     Optional<BookingAccountEntry> getByUser(Long user);
 
+    @Query(value = "SELECT * FROM booking_account_entries as e WHERE e.supplier_account_id = :supplier ORDER BY e.id DESC LIMIT 1", nativeQuery = true)
+    Optional<BookingAccountEntry> getBySupplier(Long supplier);
+
     @Query(value = "SELECT * FROM booking_account_entries as e WHERE e.is_main_account = 1 ORDER BY e.id DESC LIMIT 1", nativeQuery = true)
     Optional<BookingAccountEntry> getByMain();
 

prototype/src/main/java/org/hso/ecommerce/repos/cronjob/BackgroundJobRepository.java

@@ -0,0 +1,10 @@
+package org.hso.ecommerce.repos.cronjob;
+
+import org.hso.ecommerce.entities.cron.BackgroundJob;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface BackgroundJobRepository extends JpaRepository<BackgroundJob, Long> {
+
+}

prototype/src/main/java/org/hso/ecommerce/repos/shop/CustomerOderRepository.java

@@ -2,10 +2,16 @@ package org.hso.ecommerce.repos.shop;
 
 import org.hso.ecommerce.entities.shop.CustomerOrder;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
 import org.springframework.stereotype.Repository;
 
 @Repository
 public interface CustomerOderRepository extends JpaRepository<CustomerOrder, Long> {
 
+    @Query("SELECT SUM(cop.quantity) FROM CustomerOrderPosition cop JOIN cop.order co WHERE cop.article.id = :articleId AND co.created >= :begin AND co.created < :end")
+    Integer countOrdersOfArticleInTimespan(
+            long articleId, java.sql.Timestamp begin, java.sql.Timestamp end
+    );
+
 }
 

prototype/src/main/java/org/hso/ecommerce/repos/supplier/ArticleOfferRepository.java

@@ -0,0 +1,8 @@
+package org.hso.ecommerce.repos.supplier;
+
+import org.hso.ecommerce.entities.supplier.ArticleOffer;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+public interface ArticleOfferRepository extends JpaRepository<ArticleOffer, Long> {
+
+}

prototype/src/main/java/org/hso/ecommerce/repos/supplier/SupplierOrderRepository.java

@@ -0,0 +1,14 @@
+package org.hso.ecommerce.repos.supplier;
+
+import org.hso.ecommerce.entities.supplier.SupplierOrder;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface SupplierOrderRepository extends JpaRepository<SupplierOrder, Long> {
+
+    @Query("SELECT SUM(so.numberOfUnits) FROM SupplierOrder so JOIN so.ordered ao WHERE ao.articleNumber = :articleNumber AND so.delivered IS NULL")
+    Integer countUndeliveredReorders(String articleNumber);
+
+}

prototype/src/main/java/org/hso/ecommerce/repos/supplier/SupplierRepository.java

@@ -0,0 +1,10 @@
+package org.hso.ecommerce.repos.supplier;
+
+import org.hso.ecommerce.entities.supplier.Supplier;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface SupplierRepository extends JpaRepository<Supplier, Long> {
+
+}

supplier/.gitignore

@@ -0,0 +1,32 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

supplier/build.gradle

@@ -0,0 +1,29 @@
+plugins {
+	id 'org.springframework.boot' version '2.2.7.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
+	id 'java'
+}
+
+group = 'org.hso.ecommerce'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '11'
+
+apply plugin: 'java'
+apply plugin: 'idea'
+apply plugin: 'org.springframework.boot'
+apply plugin: 'io.spring.dependency-management'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	testImplementation('org.springframework.boot:spring-boot-starter-test') {
+		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+	}
+}
+
+test {
+	useJUnitPlatform()
+}

supplier/config/bank.json

@@ -0,0 +1,26 @@
+{
+  "id" : "bank",
+  "name" : "Bank of Cheese",
+  "discount" : {
+    "minimumDailySalesVolumeNetCent": 100,
+    "percentDiscount": 1
+  },
+  "articles": [
+    {
+      "title": "Big Mac",
+      "manufacturer": "Mc Donalds",
+      "articleNumber": "0x1 BIGMAC",
+      "vatPercent": 7,
+      "pricePerUnitNet": 700,
+      "shouldBeAdvertised": true
+    },
+    {
+      "title": "500£ Schein",
+      "manufacturer": "Bank",
+      "articleNumber": "500",
+      "vatPercent": 0,
+      "pricePerUnitNet": 50000,
+      "shouldBeAdvertised": false
+    }
+  ]
+}

supplier/config/hans-and-more.json

@@ -0,0 +1,34 @@
+{
+  "id" : "hans",
+  "name" : "Hans and more",
+  "discount" : {
+    "minimumDailySalesVolumeNetCent": 100000,
+    "percentDiscount": 2
+  },
+  "articles": [
+    {
+      "title": "Big Mac",
+      "manufacturer": "Mc Donalds",
+      "articleNumber": "0x1 BIGMAC",
+      "vatPercent": 7,
+      "pricePerUnitNet": 700,
+      "shouldBeAdvertised": true
+    },
+    {
+      "title": "Pommes",
+      "manufacturer": "Mc Donalds",
+      "articleNumber": "0x1 POmes",
+      "vatPercent": 7,
+      "pricePerUnitNet": 100,
+      "shouldBeAdvertised": false
+    },
+    {
+      "title": "Milchshake Premium 19%",
+      "manufacturer": "Mc Donalds",
+      "articleNumber": "0x2",
+      "vatPercent": 19,
+      "pricePerUnitNet": 50,
+      "shouldBeAdvertised": true
+    }
+  ]
+}

supplier/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.4-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

supplier/gradlew

@@ -0,0 +1,185 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 the original author or authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"

supplier/gradlew.bat

@@ -0,0 +1,104 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

supplier/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'supplier'

supplier/src/main/java/org/hso/ecommerce/supplier/App.java

@@ -0,0 +1,11 @@
+package org.hso.ecommerce.supplier;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class App {
+    public static void main(String[] args) {
+        SpringApplication.run(App.class, args);
+    }
+}

supplier/src/main/java/org/hso/ecommerce/supplier/ConfigurationReader.java

@@ -0,0 +1,45 @@
+package org.hso.ecommerce.supplier;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import org.hso.ecommerce.supplier.data.Supplier;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+import java.util.stream.Collectors;
+
+public class ConfigurationReader {
+
+    public static List<Supplier> read() throws IOException {
+        File dir = new File("./config/");
+
+        System.out.println("Loading Config in " + dir.getAbsolutePath());
+        ArrayList<Supplier> ret = Files.list(dir.toPath()).map(path -> {
+
+            System.out.println("Iterating over; " + path);
+            if (path.toString().endsWith(".json")) {
+                try {
+                    String jsonData = Files.readString(path, StandardCharsets.UTF_8);
+                    ObjectMapper objectMapper = new ObjectMapper();
+                    Supplier sup = objectMapper.readValue(jsonData, Supplier.class);
+                    System.out.println("Loaded " + sup.id);
+                    return sup;
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            } else {
+                System.out.println("Skipping because of file extension.");
+            }
+            return null;
+        }).collect(Collectors.toCollection(ArrayList::new));
+
+        ret.removeIf(Objects::isNull);
+
+        return ret;
+    }
+}
+

supplier/src/main/java/org/hso/ecommerce/supplier/RequestController.java

@@ -0,0 +1,88 @@
+package org.hso.ecommerce.supplier;
+
+import org.hso.ecommerce.supplier.data.Article;
+import org.hso.ecommerce.supplier.data.Order;
+import org.hso.ecommerce.supplier.data.OrderConfirmation;
+import org.hso.ecommerce.supplier.data.Supplier;
+import org.springframework.web.bind.annotation.*;
+
+import javax.annotation.PostConstruct;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.text.SimpleDateFormat;
+import java.util.ArrayList;
+import java.util.Date;
+import java.util.HashMap;
+import java.util.List;
+
+@RestController
+public class RequestController {
+
+    private final HashMap<String, Integer> dailySalesVolumeCent = new HashMap<>();
+    private final HashMap<String, Supplier> knownSuppliers  = new HashMap<>();
+    private final SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");
+
+    @PostConstruct
+    public void init() throws IOException {
+        for (Supplier s : ConfigurationReader.read()) {
+            knownSuppliers.put(s.id, s);
+        }
+    }
+
+
+    @GetMapping("/")
+    public List<Supplier> index() {
+        return new ArrayList<>(knownSuppliers.values());
+    }
+
+    @GetMapping("/{supplier}/")
+    public Supplier supplier(HttpServletResponse res, @PathVariable("supplier") String supplierName) {
+        Supplier s = knownSuppliers.get(supplierName);
+        if(s == null) {
+            res.setStatus(HttpServletResponse.SC_NOT_FOUND);
+        }
+        return s;
+    }
+
+    @PostMapping("/{supplier}/order")
+    public OrderConfirmation order(HttpServletResponse res, @PathVariable("supplier") String supplierName, @RequestBody Order order) {
+        Supplier s = knownSuppliers.get(supplierName);
+        if(s == null) {
+            res.setStatus(HttpServletResponse.SC_NOT_FOUND);
+            return null;
+        }
+
+        String dateKey = simpleDateFormat.format(new Date());
+        int dailyVolume = dailySalesVolumeCent.getOrDefault(dateKey,0);
+
+        Article a = s.findArticle(order.manufacturer, order.articleNumber);
+        if(a == null) {
+            res.setStatus(HttpServletResponse.SC_BAD_REQUEST);
+            return null;
+        }
+
+        int priceNet = a.pricePerUnitNet * order.quantity;
+        int discount = 0;
+        if(dailyVolume >= s.discount.minimumDailySalesVolumeNetCent) {
+            discount = (priceNet * s.discount.percentDiscount) / 100;
+        }
+
+        OrderConfirmation confirmation = new OrderConfirmation();
+        confirmation.articleNumber = order.articleNumber;
+        confirmation.discountNetCent = discount;
+        confirmation.pricePerUnitNetCent = a.pricePerUnitNet;
+        confirmation.manufacturer = a.manufacturer;
+        confirmation.quantity = order.quantity;
+        confirmation.totalPriceNetCharged = priceNet - discount;
+
+        if (confirmation.totalPriceNetCharged > order.maxTotalPriceCentNet) {
+            res.setStatus(HttpServletResponse.SC_EXPECTATION_FAILED);
+            return null;
+        }
+
+        dailyVolume += confirmation.totalPriceNetCharged;
+        dailySalesVolumeCent.put(dateKey, dailyVolume);
+
+        return confirmation;
+    }
+}

supplier/src/main/java/org/hso/ecommerce/supplier/data/Article.java

@@ -0,0 +1,11 @@
+package org.hso.ecommerce.supplier.data;
+
+public class Article {
+    public String title;
+    public String manufacturer;
+    public String articleNumber;
+
+    public int vatPercent;
+    public int pricePerUnitNet;
+    public boolean shouldBeAdvertised;
+}

supplier/src/main/java/org/hso/ecommerce/supplier/data/Order.java

@@ -0,0 +1,9 @@
+package org.hso.ecommerce.supplier.data;
+
+public class Order {
+    public String manufacturer;
+    public String articleNumber;
+
+    public int quantity;
+    public int maxTotalPriceCentNet;
+}

supplier/src/main/java/org/hso/ecommerce/supplier/data/OrderConfirmation.java

@@ -0,0 +1,12 @@
+package org.hso.ecommerce.supplier.data;
+
+public class OrderConfirmation {
+    public String manufacturer;
+    public String articleNumber;
+
+    public int quantity;
+
+    public int pricePerUnitNetCent;
+    public int discountNetCent;
+    public int totalPriceNetCharged;
+}

supplier/src/main/java/org/hso/ecommerce/supplier/data/Supplier.java

@@ -0,0 +1,21 @@
+package org.hso.ecommerce.supplier.data;
+
+import java.util.List;
+
+public class Supplier {
+
+    public String id;
+    public String name;
+    public SupplierDiscount discount;
+    public List<Article> articles;
+
+    public Article findArticle(String manufacturer, String articleNumber) {
+        for(Article a : articles) {
+            if(a.manufacturer.equals(manufacturer) && a.articleNumber.equals(articleNumber)) {
+                return a;
+            }
+        }
+
+        return null;
+    }
+}

supplier/src/main/java/org/hso/ecommerce/supplier/data/SupplierDiscount.java

@@ -0,0 +1,6 @@
+package org.hso.ecommerce.supplier.data;
+
+public class SupplierDiscount {
+    public int minimumDailySalesVolumeNetCent;
+    public int percentDiscount;
+}

supplier/src/main/resources/application.properties

@@ -0,0 +1,2 @@
+server.address=::1
+server.port=8081