package delivery_test

import (
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/google/uuid"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"sneak.berlin/go/webhooker/internal/database"
	"sneak.berlin/go/webhooker/internal/delivery"
)

// eventQuery is the query string the events in these tests arrived
// with.
const eventQuery = "a=1&b=2"

// httpTargetConfig is the stored configuration of an HTTP target at
// targetURL.
func httpTargetConfig(
	t *testing.T, targetURL string, forwardQuery bool,
) string {
	t.Helper()

	cfg, err := json.Marshal(delivery.HTTPTargetConfig{
		URL: targetURL, ForwardQuery: forwardQuery,
	})
	require.NoError(t, err)

	return string(cfg)
}

// deliverWithQuery sends one event that arrived with eventQuery to an
// HTTP target configured with cfg, through the path a received event's
// delivery takes, and returns the attempt it recorded.
func deliverWithQuery(t *testing.T, cfg string) database.DeliveryResult {
	t.Helper()

	s := newISetup(t)

	event := iSeedEvent(t, s.WebhookDB, s.WebhookID, "{}")
	d := iSeedDelivery(
		t, s.WebhookDB, event.ID, uuid.NewString(),
		database.DeliveryStatusPending,
	)
	task := iTask(
		d, event, s.WebhookID, d.TargetID, "query", cfg, 0, 1, &event.Body,
	)
	task.RawQuery = eventQuery

	s.Engine.ExportProcessNewTask(context.TODO(), &task)

	var result database.DeliveryResult

	require.NoError(t, s.WebhookDB.Where(
		"delivery_id = ?", d.ID,
	).First(&result).Error)

	return result
}

// TestDeliverHTTP_ForwardQuery proves the URL a delivery is sent to:
// with the target's setting off, the target URL exactly as configured;
// with it on, the event's query string appended, joined with "&" to a
// query string the target URL already has.
func TestDeliverHTTP_ForwardQuery(t *testing.T) {
	t.Parallel()

	// The target URL's path, without and with a query string of its
	// own.
	const (
		plain     = "/in"
		withQuery = "/in?key=k"
	)

	tests := map[string]struct {
		path         string
		forwardQuery bool
		want         string
	}{
		"off": {
			path: plain, want: plain,
		},
		"off, the target URL has a query string": {
			path: withQuery, want: withQuery,
		},
		"on": {
			path: plain, forwardQuery: true, want: plain + "?" + eventQuery,
		},
		"on, the target URL has a query string": {
			path: withQuery, forwardQuery: true,
			want: withQuery + "&" + eventQuery,
		},
	}

	for name, tc := range tests {
		t.Run(name, func(t *testing.T) {
			t.Parallel()

			received := make(chan string, 1)

			ts := httptest.NewServer(http.HandlerFunc(
				func(w http.ResponseWriter, r *http.Request) {
					received <- r.RequestURI

					w.WriteHeader(http.StatusOK)
				},
			))
			t.Cleanup(ts.Close)

			result := deliverWithQuery(t, httpTargetConfig(
				t, ts.URL+tc.path, tc.forwardQuery,
			))

			assert.True(t, result.Success)
			require.Len(t, received, 1)
			assert.Equal(t, tc.want, <-received)
		})
	}
}

// TestDeliverHTTP_ForwardedQueryKeepsTheTargetURLMasked proves the
// credential in a target URL's own query string stays masked once the
// event's query string is appended to it: in a response or error that
// echoes the URL the target was sent, as the event log's Redactor shows
// it, and in the error a failed connection stores.
func TestDeliverHTTP_ForwardedQueryKeepsTheTargetURLMasked(t *testing.T) {
	t.Parallel()

	const secret = "s3cr3t"

	received := make(chan string, 1)

	ts := httptest.NewServer(http.HandlerFunc(
		func(w http.ResponseWriter, r *http.Request) {
			received <- r.RequestURI

			w.WriteHeader(http.StatusBadRequest)
		},
	))
	t.Cleanup(ts.Close)

	target := &database.Target{
		Type:   database.TargetTypeHTTP,
		Config: httpTargetConfig(t, ts.URL+"/in?token="+secret, true),
	}

	deliverWithQuery(t, target.Config)
	require.Len(t, received, 1)

	sent := <-received
	require.Equal(t, "/in?token="+secret+"&"+eventQuery, sent)

	redactor := delivery.NewRedactor(target)

	for _, echoed := range []string{sent, ts.URL + sent} {
		shown := redactor.Redact("rejected " + echoed)
		assert.NotContains(t, shown, secret, echoed)
		assert.Contains(t, shown, delivery.RedactionMarker, echoed)
	}

	// Nothing listens on port 1.
	failed := deliverWithQuery(t, httpTargetConfig(
		t, "http://127.0.0.1:1/in?token="+secret, true,
	))
	require.NotEmpty(t, failed.Error)
	assert.NotContains(t, failed.Error, secret)
	assert.NotContains(t, failed.Error, eventQuery)
}