package observability

import (
	"io"
	"log/slog"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"
)

func TestRequestIDSetsHeaderAndContext(t *testing.T) {
	handler := RequestID()(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if got := RequestIDFromContext(r.Context()); got == "" {
			t.Fatal("RequestIDFromContext() = empty, want non-empty")
		}
		w.WriteHeader(http.StatusNoContent)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)

	if rec.Header().Get("X-Request-Id") == "" {
		t.Fatal("X-Request-Id header = empty, want non-empty")
	}
}

func TestTimeoutAddsContextDeadline(t *testing.T) {
	handler := Timeout(50 * time.Millisecond)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if _, ok := r.Context().Deadline(); !ok {
			t.Fatal("context deadline missing")
		}
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want %d", rec.Code, http.StatusOK)
	}
}

func TestRecoverHandlesPanic(t *testing.T) {
	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
	handler := Recover(logger)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		panic("boom")
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)

	if rec.Code != http.StatusInternalServerError {
		t.Fatalf("status = %d, want %d", rec.Code, http.StatusInternalServerError)
	}
}