package calls

import (
	"bytes"
	"encoding/base64"
	"io"
	"log/slog"
	"net/http"
	"net/http/httptest"
	"path/filepath"
	"strings"
	"testing"

	"amadan.net/oficina/home/connect"
	assertioncrypto "amadan.net/rastrillo/rastrillo/crypto"
	"amadan.net/rastrillo/rastrillo/db"
)

const homeTestDirectory = "https://directory.example.test"

// newHomeConsumerFixture configures Home the way production does: from the
// environment, through connect.CredentialsFromEnv (cmd/calls/main.go), so
// HOME_DIRECTORY_ORIGIN (unprefixed, the name Home itself reads) is read
// exactly as it is live.
func newHomeConsumerFixture(t *testing.T, directory string) *homeRouterFixture {
	t.Helper()
	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
	d, err := db.Open(filepath.Join(t.TempDir(), "calls.db"), logger)
	if err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() { d.Close() })
	key, err := assertioncrypto.Generate()
	if err != nil {
		t.Fatal(err)
	}
	t.Setenv("CALLS_HOME_ISSUER", homeTestIssuer)
	t.Setenv("CALLS_HOME_CONSUMER_ID", "calls-test")
	t.Setenv("CALLS_HOME_KEYS_BASE64", homeKeysBase64(key))
	t.Setenv("CALLS_HOME_DEK_BASE64", base64.StdEncoding.EncodeToString(bytes.Repeat([]byte{7}, 32)))
	t.Setenv("HOME_DIRECTORY_ORIGIN", directory)
	return newHomeRouterFixtureWith(t, d, logger, key, connect.CredentialsFromEnv("CALLS"))
}

// Sign out in Calls ends the id.* session too: the app session ends and
// the same POST is handed on (307) to {issuer}/signout, which returns the
// browser to /signed-out. Without it the next "Sign in" passed silently
// through the live id.* session (spec shared-chrome §9.5).
func TestHomeSignoutChainsToIssuer(t *testing.T) {
	f := newHomeConsumerFixture(t, "")
	f.local(t)
	w := f.do("POST", "/signout", "")
	if w.Code != http.StatusTemporaryRedirect || w.Header().Get("Location") != homeTestIssuer+"/signout" {
		t.Fatalf("POST /signout: status %d Location %q, want 307 to %s/signout", w.Code, w.Header().Get("Location"), homeTestIssuer)
	}
	if got := w.Header().Get("Referrer-Policy"); got != "strict-origin-when-cross-origin" {
		t.Fatalf("Referrer-Policy %q: id.* admits the null-Origin hop by Referer", got)
	}
	if f.cookies[f.app.home.sessions.CookieName()] != nil {
		t.Fatal("sign-out kept the Calls session cookie")
	}
}

// A signed-in person who follows a "Sign in" link goes straight to where
// they were headed, with no second exchange.
func TestHomeSigninWhenSignedInReturnsToPage(t *testing.T) {
	f := newHomeConsumerFixture(t, "")
	f.local(t)
	if got := homeRedirect(t, f.do("GET", "/signin?return_to=%2Fsettings", "")); got != "/settings" {
		t.Fatalf("signed-in /signin went to %q, want /settings", got)
	}
}

// "All apps" goes to the hub directory, from HOME_DIRECTORY_ORIGIN, in the
// account corner, and is absent when no directory is configured.
func TestAllAppsLinksToDirectory(t *testing.T) {
	link := `href="` + homeTestDirectory + `/"`
	f := newHomeConsumerFixture(t, homeTestDirectory)
	f.local(t)
	for _, path := range []string{"/", "/settings"} {
		w := f.do("GET", path, "")
		if body := w.Body.String(); w.Code != http.StatusOK || !strings.Contains(body, link) || !strings.Contains(body, ">All apps<") {
			t.Fatalf("GET %s (%d): no All apps link to %s/", path, w.Code, homeTestDirectory)
		}
	}

	bare := newHomeConsumerFixture(t, "")
	bare.local(t)
	if body := bare.do("GET", "/", "").Body.String(); strings.Contains(body, "All apps") {
		t.Fatal("All apps shown with no directory configured")
	}
}

// homeSignout asserts the Home-mode sign-out response: a 307 on to the
// issuer's /signout, which returns the browser to /signed-out.
func homeSignout(t *testing.T, w *httptest.ResponseRecorder) {
	t.Helper()
	if w.Code != http.StatusTemporaryRedirect || w.Header().Get("Location") != homeTestIssuer+"/signout" {
		t.Fatalf("POST /signout: status %d Location %q, want 307 to %s/signout", w.Code, w.Header().Get("Location"), homeTestIssuer)
	}
}

// A signed-out visit to a page in Home mode goes to sign-in carrying the
// page, and Home sign-in comes back to that exact page, not the root.
func TestHomeSigninReturnsToTheExactPage(t *testing.T) {
	f := newHomeConsumerFixture(t, "")
	f.link(t)
	homeSignout(t, f.do("POST", "/signout", ""))

	signin := homeRedirect(t, f.do("GET", "/settings", ""))
	if signin != "/signin?return_to=%2Fsettings" {
		t.Fatalf("signed-out /settings went to %q, want /signin?return_to=%%2Fsettings", signin)
	}
	start := homeRedirect(t, f.do("GET", signin, ""))
	if got := homeRedirect(t, f.exchange(t, start, "opaque-home-alice")); got != "/settings" {
		t.Fatalf("Home sign-in landed on %q, want /settings", got)
	}
}