1 files changed, 88 insertions, 0 deletions
diff --git a/fmi_client.go b/fmi_client.go
new file mode 100644
index 0000000..e4b59b2
--- /dev/null
+++ b/fmi_client.go
@@ -0,0 +1,88 @@
+// fmi_client.go - FMI API client library
+package main
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"time"
+)
+
+// FMIClient handles FMI API interactions
+type FMIClient struct {
+	BaseURL       string
+	HTTPClient    *http.Client
+	WeatherMapper *WeatherMapper
+}
+
+// NewFMIClient creates a new FMI client
+func NewFMIClient() *FMIClient {
+	return &FMIClient{
+		BaseURL:       "https://opendata.fmi.fi/wfs",
+		HTTPClient:    &http.Client{Timeout: 30 * time.Second},
+		WeatherMapper: NewWeatherMapper(),
+	}
+}
+
+// GetForecast fetches and parses forecast for a location
+func (c *FMIClient) GetForecast(location string) (*OWMResponse, error) {
+	// Build request URL
+	url, err := c.buildURL(location)
+	if err != nil {
+		return nil, fmt.Errorf("building URL: %w", err)
+	}
+
+	// Fetch XML data
+	xmlData, err := c.fetchXML(url)
+	if err != nil {
+		return nil, fmt.Errorf("fetching XML: %w", err)
+	}
+
+	// Parse XML
+	forecastData, err := ParseForecastXML(xmlData)
+	if err != nil {
+		return nil, fmt.Errorf("parsing XML: %w", err)
+	}
+
+	// Convert to OWM format
+	response, err := forecastData.ToOWMResponse(c.WeatherMapper)
+	if err != nil {
+		return nil, fmt.Errorf("converting to OWM format: %w", err)
+	}
+
+	return response, nil
+}
+
+func (c *FMIClient) buildURL(location string) (string, error) {
+	baseURL, err := url.Parse(c.BaseURL)
+	if err != nil {
+		return "", err
+	}
+
+	q := baseURL.Query()
+	q.Set("service", "WFS")
+	q.Set("version", "2.0.0")
+	q.Set("request", "getFeature")
+	q.Set("storedquery_id", "fmi::forecast::harmonie::surface::point::multipointcoverage")
+	q.Set("place", location)
+	q.Set("parameters", "Temperature,PrecipitationRate,Humidity,Pressure,dewPoint,visibility,WindSpeedMS,WindDirection,WindGust,TotalCloudCover,WeatherSymbol3")
+
+	baseURL.RawQuery = q.Encode()
+	return baseURL.String(), nil
+}
+
+func (c *FMIClient) fetchXML(url string) ([]byte, error) {
+	resp, err := c.HTTPClient.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		body, _ := io.ReadAll(resp.Body)
+		return nil, fmt.Errorf("HTTP %d: %s", resp.StatusCode, string(body))
+	}
+
+	return io.ReadAll(resp.Body)
+}