package middleware_test

import (
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/food-ai/backend/internal/infra/middleware"
)

func TestRequestID_GeneratesNew(t *testing.T) {
	handler := middleware.RequestID(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		id := middleware.RequestIDFromCtx(r.Context())
		if id == "" {
			t.Error("expected non-empty request ID in context")
		}
	}))

	req := httptest.NewRequest("GET", "/", nil)
	rr := httptest.NewRecorder()

	handler.ServeHTTP(rr, req)
	if rr.Header().Get("X-Request-ID") == "" {
		t.Error("expected X-Request-ID in response header")
	}
}

func TestRequestID_PreservesExisting(t *testing.T) {
	handler := middleware.RequestID(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		id := middleware.RequestIDFromCtx(r.Context())
		if id != "existing-id" {
			t.Errorf("expected 'existing-id', got %q", id)
		}
	}))

	req := httptest.NewRequest("GET", "/", nil)
	req.Header.Set("X-Request-ID", "existing-id")
	rr := httptest.NewRecorder()

	handler.ServeHTTP(rr, req)
	if rr.Header().Get("X-Request-ID") != "existing-id" {
		t.Error("expected preserved X-Request-ID")
	}
}

func TestRequestID_UniquePerRequest(t *testing.T) {
	var ids []string
	handler := middleware.RequestID(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		ids = append(ids, middleware.RequestIDFromCtx(r.Context()))
	}))

	for i := 0; i < 3; i++ {
		req := httptest.NewRequest("GET", "/", nil)
		rr := httptest.NewRecorder()
		handler.ServeHTTP(rr, req)
	}

	if ids[0] == ids[1] || ids[1] == ids[2] {
		t.Error("expected unique IDs for each request")
	}
}