Initial MVP commit

internal/adapters/httpapi/server.go

@@ -0,0 +1,110 @@
+package httpapi
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"time"
+
+	"gitea.maximumdirect.net/ejr/weatherapi/internal/application/alerts"
+	"gitea.maximumdirect.net/ejr/weatherapi/internal/application/forecasts"
+	"gitea.maximumdirect.net/ejr/weatherapi/internal/application/observations"
+	"gitea.maximumdirect.net/ejr/weatherapi/internal/platform/timeparse"
+)
+
+type ObservationService interface {
+	GetCurrent(ctx context.Context) (observations.CurrentResponse, error)
+}
+
+type ForecastService interface {
+	GetByTimestamp(ctx context.Context, ts time.Time) (forecasts.Response, error)
+}
+
+type AlertService interface {
+	GetCurrent(ctx context.Context) (alerts.Response, error)
+}
+
+type Server struct {
+	obsSvc    ObservationService
+	fcSvc     ForecastService
+	alertsSvc AlertService
+}
+
+func NewServer(obsSvc ObservationService, fcSvc ForecastService, alertsSvc AlertService) *Server {
+	return &Server{obsSvc: obsSvc, fcSvc: fcSvc, alertsSvc: alertsSvc}
+}
+
+func (s *Server) Handler() http.Handler {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/observations/current", s.handleObservationsCurrent)
+	mux.HandleFunc("/forecast", s.handleForecast)
+	mux.HandleFunc("/alerts/current", s.handleAlertsCurrent)
+	return mux
+}
+
+func (s *Server) handleObservationsCurrent(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		writeError(w, http.StatusMethodNotAllowed, "method_not_allowed", "only GET is supported")
+		return
+	}
+
+	resp, err := s.obsSvc.GetCurrent(r.Context())
+	if err != nil {
+		writeError(w, http.StatusInternalServerError, "internal_error", "failed to fetch current observations")
+		return
+	}
+
+	writeJSON(w, http.StatusOK, resp)
+}
+
+func (s *Server) handleForecast(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		writeError(w, http.StatusMethodNotAllowed, "method_not_allowed", "only GET is supported")
+		return
+	}
+
+	raw := r.URL.Query().Get("timestamp")
+	ts, err := timeparse.ParseTimestamp(raw)
+	if err != nil {
+		writeError(w, http.StatusBadRequest, "invalid_request", err.Error())
+		return
+	}
+
+	resp, err := s.fcSvc.GetByTimestamp(r.Context(), ts)
+	if err != nil {
+		writeError(w, http.StatusInternalServerError, "internal_error", "failed to fetch forecast")
+		return
+	}
+
+	writeJSON(w, http.StatusOK, resp)
+}
+
+func (s *Server) handleAlertsCurrent(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		writeError(w, http.StatusMethodNotAllowed, "method_not_allowed", "only GET is supported")
+		return
+	}
+
+	resp, err := s.alertsSvc.GetCurrent(r.Context())
+	if err != nil {
+		writeError(w, http.StatusInternalServerError, "internal_error", "failed to fetch current alerts")
+		return
+	}
+
+	writeJSON(w, http.StatusOK, resp)
+}
+
+type errorResponse struct {
+	Code    string `json:"code"`
+	Message string `json:"message"`
+}
+
+func writeError(w http.ResponseWriter, status int, code, message string) {
+	writeJSON(w, status, errorResponse{Code: code, Message: message})
+}
+
+func writeJSON(w http.ResponseWriter, status int, payload any) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	_ = json.NewEncoder(w).Encode(payload)
+}