package e2e

import (
	"net/http"
	"os/exec"
	"strings"
	"testing"
)

// A stylesheet a browser cannot keep is refetched on every click, and the page flashes unstyled.
func TestTheStylesheetIsKeptBetweenPages(t *testing.T) {
	if _, err := exec.LookPath("git"); err != nil {
		t.Skip("git is not installed")
	}
	in := newInstance(t)
	john := in.account("john")
	seed(t, in, john, "john", "johnbot")

	// Every page asks for the stylesheet under the running version, which is what makes it keepable.
	_, _, body := get(t, in.http.URL+"/john/johnbot")
	i := strings.Index(body, "/static/barerepo.css")
	if i < 0 {
		t.Fatalf("no stylesheet on the page:\n%s", body)
	}
	href := body[i : strings.Index(body[i:], `"`)+i]
	if !strings.Contains(href, "?v=") {
		t.Errorf("the stylesheet url carries no version, so it can only be cached by guessing: %s", href)
	}

	resp, err := http.Get(in.http.URL + href)
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	cc := resp.Header.Get("Cache-Control")
	if !strings.Contains(cc, "immutable") || !strings.Contains(cc, "max-age=") {
		t.Errorf("the versioned stylesheet answered Cache-Control %q, so a browser refetches it", cc)
	}

	// And a bookmarked url with no version still says something, or that request flashes too.
	plain, err := http.Get(in.http.URL + "/static/barerepo.css")
	if err != nil {
		t.Fatal(err)
	}
	defer plain.Body.Close()
	if plain.Header.Get("Cache-Control") == "" {
		t.Error("an unversioned stylesheet answers with no caching policy at all")
	}
}

// A url cached for a year must change when the file does, or an edit reaches nobody who has it.
func TestTheStylesheetUrlIsNotTheReleaseNumber(t *testing.T) {
	if _, err := exec.LookPath("git"); err != nil {
		t.Skip("git is not installed")
	}
	in := newInstance(t)
	john := in.account("john")
	seed(t, in, john, "john", "johnbot")

	_, _, body := get(t, in.http.URL+"/john/johnbot")
	i := strings.Index(body, "/static/barerepo.css")
	href := body[i : strings.Index(body[i:], `"`)+i]
	_, tag, _ := strings.Cut(href, "?v=")

	// The version does not move between builds, so a stylesheet keyed on it is kept after an edit.
	if tag == "" || strings.Contains(body, "?v=0.1.0") {
		t.Errorf("the stylesheet is cached for a year under %q, which the next edit will not change", tag)
	}
	// Every page agrees, or one of them hands out a url that pins an old stylesheet.
	for _, path := range []string{"/john/johnbot/files", "/john/johnbot/config", "/signin"} {
		_, _, page := get(t, in.http.URL+path)
		if !strings.Contains(page, "?v="+tag) {
			t.Errorf("%s asks for a different stylesheet url than the log page does", path)
		}
	}
}