stocks-be/src/main/java/com/danielbohry/stocks/client/ExchangeRateClient.java

package com.danielbohry.stocks.client;

import com.danielbohry.stocks.service.ExchangeService.ExchangeRateResponse;
import lombok.RequiredArgsConstructor;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Component;
import org.springframework.web.client.HttpClientErrorException;
import org.springframework.web.client.RestTemplate;

import static org.springframework.http.HttpMethod.GET;
import static org.springframework.http.HttpStatus.OK;
import static org.springframework.http.MediaType.APPLICATION_JSON;

@Component
@RequiredArgsConstructor
public class ExchangeRateClient {

    private final RestTemplate rest;

    @Value("${clients.exchange.url}")
    private String baseUrl;

    public ExchangeRateResponse getRate(String symbol, String apiKey) {
        String url = baseUrl + "/" + apiKey + "/latest/" + symbol;

        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(APPLICATION_JSON);

        HttpEntity<Void> entity = new HttpEntity<>(headers);

        try {
            ResponseEntity<ExchangeRateResponse> response = rest.exchange(
                    url,
                    GET,
                    entity,
                    ExchangeRateResponse.class
            );

            if (response.getStatusCode() == OK) {
                return response.getBody();
            } else {
                throw new RuntimeException("Unexpected response status: " + response.getStatusCode());
            }
        } catch (HttpClientErrorException e) {
            throw new RuntimeException("Error calling exchange API: " + e.getStatusCode() + " - " + e.getResponseBodyAsString());
        } catch (Exception e) {
            throw new RuntimeException("An error occurred calling exchange API: " + e.getMessage());
        }
    }

}