package middleware_test

import (
	"context"
	"net/http"
	"testing"

	"git.codelab.vc/pkg/httpx/internal/requestid"
	"git.codelab.vc/pkg/httpx/middleware"
)

func TestRequestID(t *testing.T) {
	t.Run("propagates ID from context", func(t *testing.T) {
		var gotHeader string
		base := middleware.RoundTripperFunc(func(req *http.Request) (*http.Response, error) {
			gotHeader = req.Header.Get("X-Request-Id")
			return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}, nil
		})

		mw := middleware.RequestID()(base)

		ctx := requestid.NewContext(context.Background(), "test-id-123")
		req, _ := http.NewRequestWithContext(ctx, http.MethodGet, "http://example.com", nil)
		_, err := mw.RoundTrip(req)
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}

		if gotHeader != "test-id-123" {
			t.Fatalf("X-Request-Id = %q, want %q", gotHeader, "test-id-123")
		}
	})

	t.Run("no ID in context skips header", func(t *testing.T) {
		var gotHeader string
		base := middleware.RoundTripperFunc(func(req *http.Request) (*http.Response, error) {
			gotHeader = req.Header.Get("X-Request-Id")
			return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}, nil
		})

		mw := middleware.RequestID()(base)

		req, _ := http.NewRequestWithContext(context.Background(), http.MethodGet, "http://example.com", nil)
		_, err := mw.RoundTrip(req)
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}

		if gotHeader != "" {
			t.Fatalf("expected no X-Request-Id header, got %q", gotHeader)
		}
	})

	t.Run("does not mutate original request", func(t *testing.T) {
		base := middleware.RoundTripperFunc(func(req *http.Request) (*http.Response, error) {
			return &http.Response{StatusCode: http.StatusOK, Body: http.NoBody}, nil
		})

		mw := middleware.RequestID()(base)

		ctx := requestid.NewContext(context.Background(), "test-id")
		req, _ := http.NewRequestWithContext(ctx, http.MethodGet, "http://example.com", nil)
		_, _ = mw.RoundTrip(req)

		if req.Header.Get("X-Request-Id") != "" {
			t.Fatal("original request was mutated")
		}
	})
}