package session_test

import (
	"errors"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"sneak.berlin/go/pixa/internal/session"
)

func TestManager_CreateAndValidate(t *testing.T) {
	t.Parallel()

	mgr, err := session.NewManager("test-signing-key-12345")
	if err != nil {
		t.Fatalf("NewManager() error = %v", err)
	}

	// Create a session
	w := httptest.NewRecorder()

	err = mgr.CreateSession(w)
	if err != nil {
		t.Fatalf("CreateSession() error = %v", err)
	}

	// Extract the cookie from response
	resp := w.Result()

	cookies := resp.Cookies()
	if len(cookies) == 0 {
		t.Fatal("CreateSession() did not set a cookie")
	}

	var sessionCookie *http.Cookie

	for _, c := range cookies {
		if c.Name == session.CookieName {
			sessionCookie = c

			break
		}
	}

	if sessionCookie == nil {
		t.Fatalf("CreateSession() did not set cookie named %q", session.CookieName)
	}

	// Validate the session
	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
	req.AddCookie(sessionCookie)

	data, err := mgr.ValidateSession(req)
	if err != nil {
		t.Fatalf("ValidateSession() error = %v", err)
	}

	if !data.Authenticated {
		t.Error("ValidateSession() returned unauthenticated session")
	}

	if data.ExpiresAt.Before(time.Now()) {
		t.Error("ValidateSession() returned already-expired session")
	}
}

func TestManager_ValidateSession_NoCookie(t *testing.T) {
	t.Parallel()

	mgr, _ := session.NewManager("test-signing-key-12345")

	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)

	_, err := mgr.ValidateSession(req)
	if err == nil {
		t.Error("ValidateSession() should fail with no cookie")
	}

	if !errors.Is(err, session.ErrNoSession) {
		t.Errorf("ValidateSession() error = %v, want %v", err, session.ErrNoSession)
	}
}

func TestManager_ValidateSession_TamperedCookie(t *testing.T) {
	t.Parallel()

	mgr, _ := session.NewManager("test-signing-key-12345")

	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
	req.AddCookie(&http.Cookie{
		Name:     session.CookieName,
		Value:    "tampered-invalid-cookie-value",
		Secure:   true,
		HttpOnly: true,
		SameSite: http.SameSiteStrictMode,
	})

	_, err := mgr.ValidateSession(req)
	if err == nil {
		t.Error("ValidateSession() should fail with tampered cookie")
	}

	if !errors.Is(err, session.ErrInvalidSession) {
		t.Errorf("ValidateSession() error = %v, want %v", err, session.ErrInvalidSession)
	}
}

func TestManager_ValidateSession_WrongKey(t *testing.T) {
	t.Parallel()

	mgr1, _ := session.NewManager("signing-key-1")
	mgr2, _ := session.NewManager("signing-key-2")

	// Create session with mgr1
	w := httptest.NewRecorder()
	_ = mgr1.CreateSession(w)

	resp := w.Result()

	var sessionCookie *http.Cookie

	for _, c := range resp.Cookies() {
		if c.Name == session.CookieName {
			sessionCookie = c

			break
		}
	}

	// Try to validate with mgr2 (different key)
	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
	req.AddCookie(sessionCookie)

	_, err := mgr2.ValidateSession(req)
	if err == nil {
		t.Error("ValidateSession() should fail with different signing key")
	}
}

func TestManager_ClearSession(t *testing.T) {
	t.Parallel()

	mgr, _ := session.NewManager("test-signing-key-12345")

	w := httptest.NewRecorder()
	mgr.ClearSession(w)

	resp := w.Result()
	cookies := resp.Cookies()

	var sessionCookie *http.Cookie

	for _, c := range cookies {
		if c.Name == session.CookieName {
			sessionCookie = c

			break
		}
	}

	if sessionCookie == nil {
		t.Fatal("ClearSession() did not set a cookie")
	}

	if sessionCookie.MaxAge != -1 {
		t.Errorf("ClearSession() cookie MaxAge = %d, want -1", sessionCookie.MaxAge)
	}
}

func TestManager_IsAuthenticated(t *testing.T) {
	t.Parallel()

	mgr, _ := session.NewManager("test-signing-key-12345")

	// No session - should return false
	req := httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
	if mgr.IsAuthenticated(req) {
		t.Error("IsAuthenticated() should return false with no session")
	}

	// Create session
	w := httptest.NewRecorder()
	_ = mgr.CreateSession(w)

	resp := w.Result()

	var sessionCookie *http.Cookie

	for _, c := range resp.Cookies() {
		if c.Name == session.CookieName {
			sessionCookie = c

			break
		}
	}

	// With valid session - should return true
	req = httptest.NewRequestWithContext(t.Context(), http.MethodGet, "/", nil)
	req.AddCookie(sessionCookie)

	if !mgr.IsAuthenticated(req) {
		t.Error("IsAuthenticated() should return true with valid session")
	}
}

func TestManager_CookieAttributes(t *testing.T) {
	t.Parallel()

	mgr, _ := session.NewManager("test-key")

	w := httptest.NewRecorder()
	_ = mgr.CreateSession(w)

	resp := w.Result()

	var sessionCookie *http.Cookie

	for _, c := range resp.Cookies() {
		if c.Name == session.CookieName {
			sessionCookie = c

			break
		}
	}

	if !sessionCookie.HttpOnly {
		t.Error("Cookie should have HttpOnly flag")
	}

	if !sessionCookie.Secure {
		t.Error("Cookie should have Secure flag when manager created with secure=true")
	}

	if sessionCookie.SameSite != http.SameSiteStrictMode {
		t.Errorf("Cookie SameSite = %v, want %v",
			sessionCookie.SameSite, http.SameSiteStrictMode)
	}
}