initial commit

src/main/java/se/urmo/electricityalert/ElectricityAlertApplication.java

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+package se.urmo.electricityalert;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.scheduling.annotation.EnableScheduling;
+
+@SpringBootApplication
+@EnableScheduling
+public class ElectricityAlertApplication {
+    public static void main(String[] args) {
+        SpringApplication.run(ElectricityAlertApplication.class, args);
+    }
+}

src/main/java/se/urmo/electricityalert/alert/AlertService.java

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+package se.urmo.electricityalert.alert;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Service;
+import se.urmo.electricityalert.model.ElectricityPrice;
+import se.urmo.electricityalert.notifier.TelegramNotifier;
+import se.urmo.electricityalert.store.InMemoryPriceStore;
+
+import java.math.BigDecimal;
+import java.time.LocalDateTime;
+
+@Service
+public class AlertService {
+    private static final Logger log = LoggerFactory.getLogger(AlertService.class);
+
+    private final InMemoryPriceStore store;
+    private final TelegramNotifier notifier;
+    private final BigDecimal threshold;
+
+    public AlertService(InMemoryPriceStore store,
+                        TelegramNotifier notifier,
+                        @Value("${electricity.threshold}") BigDecimal threshold) {
+        this.store = store;
+        this.notifier = notifier;
+        this.threshold = threshold;
+    }
+
+    // Check every 5 minutes
+    @Scheduled(fixedRate = 300_000)
+    public void checkPrices() {
+        LocalDateTime oneHourLater = LocalDateTime.now().withMinute(0).withSecond(0).plusHours(1);
+        ElectricityPrice price = store.get(oneHourLater);
+
+        if (price != null && price.price().compareTo(threshold) < 0 && !store.alreadyNotified(oneHourLater)) {
+            String msg = String.format("⚡ In the next hour (%s) the price is %.2f SEK/kWh. Plug in the car!",
+                    oneHourLater, price.price());
+            notifier.send(msg);
+            store.markNotified(oneHourLater);
+            log.info("Sent alert: {}", msg);
+        }
+    }
+}

src/main/java/se/urmo/electricityalert/fetcher/PriceFetcherService.java

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+package se.urmo.electricityalert.fetcher;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.boot.context.event.ApplicationReadyEvent;
+import org.springframework.context.event.EventListener;
+import org.springframework.http.MediaType;
+import org.springframework.stereotype.Service;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.web.client.RestClient;
+import se.urmo.electricityalert.fetcher.dto.PriceInfoDto;
+import se.urmo.electricityalert.model.ElectricityPrice;
+import se.urmo.electricityalert.store.InMemoryPriceStore;
+
+import java.time.OffsetDateTime;
+import java.time.LocalDateTime;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+@Service
+public class PriceFetcherService {
+
+    private static final Logger log = LoggerFactory.getLogger(PriceFetcherService.class);
+
+    private final InMemoryPriceStore store;
+    private final RestClient client;
+    private final boolean fetchOnStartup;
+
+
+    // Your GraphQL query (exactly as you provided, compacted into a single string)
+    private static final String QUERY = """
+        { viewer { homes { currentSubscription { priceInfo {
+            current { total energy tax startsAt }
+            today { total energy tax startsAt }
+            tomorrow { total energy tax startsAt }
+        } } } } }
+        """;
+
+    public PriceFetcherService(
+            InMemoryPriceStore store,
+            @Value("${graphql.endpoint}") String endpoint,
+            @Value("${graphql.access-token}") String accessToken,
+            @Value("${fetch.on-startup:true}") boolean fetchOnStartup) {
+        this.store = store;
+        this.fetchOnStartup = fetchOnStartup;
+        this.client = RestClient.builder()
+                .baseUrl(endpoint)
+                .defaultHeader("Authorization", "Bearer " + accessToken)
+                .build();
+    }
+
+    /** Runs every day at 13:05. */
+    @Scheduled(cron = "0 5 13 * * *")
+    public void fetchPrices() {
+        fetchPricesInternal();
+    }
+
+    /** One-time fetch after the app is fully started (beans initialized, web server up). */
+    @EventListener(ApplicationReadyEvent.class)
+    public void onReadyFetchOnce() {
+        if (!fetchOnStartup) return;
+        log.info("Application started — performing one-time price fetch...");
+        fetchPricesInternal();
+    }
+
+    /** Shared logic used by both the scheduled job and the startup hook. */
+    private void fetchPricesInternal() {
+        try {
+            Map<String, Object> body = new HashMap<>();
+            body.put("query", QUERY);
+
+            PriceInfoDto result = client.post()
+                    .contentType(MediaType.APPLICATION_JSON)
+                    .accept(MediaType.APPLICATION_JSON)
+                    .body(body)
+                    .retrieve()
+                    .body(PriceInfoDto.class);
+
+            if (result == null || result.data() == null || result.data().viewer() == null
+                    || result.data().viewer().homes() == null || result.data().viewer().homes().isEmpty()) {
+                log.warn("GraphQL response missing expected fields; nothing stored.");
+                return;
+            }
+
+            var home = result.data().viewer().homes().get(0);
+            if (home == null || home.currentSubscription() == null
+                    || home.currentSubscription().priceInfo() == null) {
+                log.warn("No priceInfo in response; nothing stored.");
+                return;
+            }
+
+            var priceInfo = home.currentSubscription().priceInfo();
+            int count = 0;
+
+            // current
+            count += storePoints(List.of(priceInfo.current()));
+            // today
+            if (priceInfo.today() != null) count += storePoints(priceInfo.today());
+            // tomorrow
+            if (priceInfo.tomorrow() != null) count += storePoints(priceInfo.tomorrow());
+
+            log.info("Stored {} price points from GraphQL.", count);
+
+        } catch (Exception e) {
+            log.error("Failed to fetch/parse GraphQL prices", e);
+        }
+    }
+
+    private int storePoints(List<PriceInfoDto.PricePoint> points) {
+        if (points == null || points.isEmpty()) return 0;
+
+        int stored = 0;
+        for (var p : points) {
+            if (p == null || p.startsAt() == null || p.total() == null) continue;
+
+            // startsAt like: 2025-09-12T11:00:00.000+02:00
+            OffsetDateTime odt = OffsetDateTime.parse(p.startsAt());
+            LocalDateTime hourLocal = odt.toLocalDateTime(); // interpret in local (offset already in string)
+
+            store.put(new ElectricityPrice(hourLocal, p.total()));
+            stored++;
+        }
+        return stored;
+    }
+}

src/main/java/se/urmo/electricityalert/fetcher/dto/PriceInfoDto.java

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+package se.urmo.electricityalert.fetcher.dto;
+
+import java.math.BigDecimal;
+import java.util.List;
+
+public record PriceInfoDto(Data data) {
+    public record Data(Viewer viewer) {}
+    public record Viewer(List<Home> homes) {}
+    public record Home(CurrentSubscription currentSubscription) {}
+    public record CurrentSubscription(PriceInfo priceInfo) {}
+    public record PriceInfo(PricePoint current, List<PricePoint> today, List<PricePoint> tomorrow) {}
+    public record PricePoint(BigDecimal total, BigDecimal energy, BigDecimal tax, String startsAt) {}
+}

src/main/java/se/urmo/electricityalert/model/ElectricityPrice.java

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+package se.urmo.electricityalert.model;
+
+import java.math.BigDecimal;
+import java.time.LocalDateTime;
+
+public record ElectricityPrice(LocalDateTime hour, BigDecimal price) {
+}

src/main/java/se/urmo/electricityalert/notifier/TelegramNotifier.java

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+package se.urmo.electricityalert.notifier;
+
+import com.pengrad.telegrambot.TelegramBot;
+import com.pengrad.telegrambot.request.SendMessage;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+@Component
+public class TelegramNotifier {
+    private final TelegramBot bot;
+    private final String chatId;
+
+    public TelegramNotifier(@Value("${telegram.bot.token}") String token,
+                            @Value("${telegram.chat.id}") String chatId) {
+        this.bot = new TelegramBot(token);
+        this.chatId = chatId;
+    }
+
+    public void send(String message) {
+        bot.execute(new SendMessage(chatId, message));
+    }
+}

src/main/java/se/urmo/electricityalert/store/InMemoryPriceStore.java

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+package se.urmo.electricityalert.store;
+
+import org.springframework.stereotype.Component;
+import se.urmo.electricityalert.model.ElectricityPrice;
+
+import java.time.LocalDateTime;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+@Component
+public class InMemoryPriceStore {
+    private final Map<LocalDateTime, ElectricityPrice> prices = new ConcurrentHashMap<>();
+    private final Set<LocalDateTime> notified = ConcurrentHashMap.newKeySet();
+
+    public void put(ElectricityPrice price) {
+        prices.put(price.hour(), price);
+    }
+
+    public ElectricityPrice get(LocalDateTime hour) {
+        return prices.get(hour);
+    }
+
+    public Map<LocalDateTime, ElectricityPrice> all() {
+        return prices;
+    }
+
+    public boolean alreadyNotified(LocalDateTime hour) {
+        return notified.contains(hour);
+    }
+
+    public void markNotified(LocalDateTime hour) {
+        notified.add(hour);
+    }
+}

src/main/resources/application.properties

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+# ? Telegram Bot
+telegram.bot.token=${TELEGRAM_BOT_TOKEN}
+telegram.chat.id=${TELEGRAM_CHAT_ID}
+
+# ? Electricity threshold (can also override via ENV if you want)
+electricity.threshold=${ELECTRICITY_THRESHOLD:0.50}
+
+# ? GraphQL
+graphql.endpoint=${GRAPHQL_ENDPOINT:https://provider.example/graphql}
+graphql.access-token=${GRAPHQL_ACCESS_TOKEN}
+
+# ?? Behavior
+fetch.on-startup=${FETCH_ON_STARTUP:true}