package chromium

import (
	"context"
	"log/slog"
	"slices"
	"strings"
	"testing"

	"github.com/dlclark/regexp2/v2"
)

// TestChromiumBrowser_Start_rejectsOverlappingStart guards against the latch
// reported in https://github.com/gotenberg/gotenberg/issues/1599. When the
// supervisor abandons a Start goroutine on request-deadline expiry, that
// goroutine keeps running and holds startMu (and the pinning proxy it started)
// until it unwinds. A second Start must be refused rather than proceeding to
// start the pinning proxy a second time.
func TestChromiumBrowser_Start_rejectsOverlappingStart(t *testing.T) {
	b := &chromiumBrowser{initialCtx: context.Background()}

	// Simulate a Start still in flight.
	b.startMu.Lock()
	defer b.startMu.Unlock()

	err := b.Start(slog.New(slog.DiscardHandler))
	if err == nil {
		t.Fatal("expected an error when a start is already in progress, got nil")
	}
	if !strings.Contains(err.Error(), "already in progress") {
		t.Fatalf("expected an 'already in progress' error, got %q", err)
	}

	// The guard must return before touching any startup resource, so no user
	// profile directory is created and the browser stays not started.
	if b.userProfileDirPath != "" {
		t.Fatalf("expected no user profile directory to be created, got %q", b.userProfileDirPath)
	}
	if b.isStarted.Load() {
		t.Fatal("expected the browser to stay not started")
	}
}

// TestChromiumDisableFeatures guards the override described in
// https://github.com/gotenberg/gotenberg/issues/1656. Gotenberg replaces
// chromedp's --disable-features value rather than extending it, as
// chromedp.Flag keys its flags by switch name. Dropping one of chromedp's own
// entries while editing this list would silently re-enable it.
func TestChromiumDisableFeatures(t *testing.T) {
	for _, feature := range []string{
		// chromedp.DefaultExecAllocatorOptions.
		"site-per-process",
		"Translate",
		"BlinkGenPropertyTrees",
		// The address-bar popup WebUI, built even in headless.
		"WebUIOmniboxPopup",
		"WebUIOmniboxAimPopup",
	} {
		if !slices.Contains(strings.Split(chromiumDisableFeatures, ","), feature) {
			t.Errorf("expected %q to be disabled, got %q", feature, chromiumDisableFeatures)
		}
	}
}

// A WebSocket the outbound policy rejects must reach the pinning proxy, so
// the implicit loopback proxy bypass is removed whenever a policy can reject
// a network URL. See GHSA-73vq-mh8c-27wg.
func TestBrowserArguments_restrictsNetwork(t *testing.T) {
	re := func(patterns ...string) []*regexp2.Regexp {
		var res []*regexp2.Regexp
		for _, p := range patterns {
			res = append(res, regexp2.MustCompile(p, regexp2.None))
		}
		return res
	}

	for _, tc := range []struct {
		scenario string
		args     browserArguments
		expect   bool
	}{
		{scenario: "default deny-list only", args: browserArguments{denyList: re(defaultDenyListPattern)}, expect: false},
		{scenario: "no lists", args: browserArguments{}, expect: false},
		{scenario: "allow-list", args: browserArguments{allowList: re(`^https://example\.com`), denyList: re(defaultDenyListPattern)}, expect: true},
		{scenario: "custom deny-list", args: browserArguments{denyList: re(`^http://internal`)}, expect: true},
		{scenario: "default and custom deny-list", args: browserArguments{denyList: re(defaultDenyListPattern, `^http://internal`)}, expect: true},
		{scenario: "deny private IPs", args: browserArguments{denyList: re(defaultDenyListPattern), denyPrivateIPs: true}, expect: true},
		{scenario: "deny public IPs", args: browserArguments{denyPublicIPs: true}, expect: true},
	} {
		t.Run(tc.scenario, func(t *testing.T) {
			if got := tc.args.restrictsNetwork(); got != tc.expect {
				t.Fatalf("restrictsNetwork() = %t, want %t", got, tc.expect)
			}
		})
	}
}