package handlers

import (
	"context"
	"net/http"
	"net/http/httptest"
	"net/url"
	"path/filepath"
	"regexp"
	"strings"
	"testing"

	"veola/internal/apify"
	"veola/internal/auth"
	"veola/internal/config"
	"veola/internal/crypto"
	"veola/internal/db"
	"veola/internal/models"
	"veola/internal/ntfy"
	"veola/internal/scheduler"
)

// newTestApp builds an App backed by a fresh sqlite db in t.TempDir(). The
// scheduler, apify, and ntfy clients are wired but unused by the routes we
// hit here. The returned http.Handler is App.Routes().
func newTestApp(t *testing.T) (*App, http.Handler) {
	t.Helper()
	dbPath := filepath.Join(t.TempDir(), "test.db")
	sqlDB, err := db.Open(dbPath)
	if err != nil {
		t.Fatalf("db.Open: %v", err)
	}
	t.Cleanup(func() { sqlDB.Close() })

	key, err := crypto.DeriveKey([]byte("test-encryption-key-32-bytes-min-aaaaaa"))
	if err != nil {
		t.Fatalf("DeriveKey: %v", err)
	}
	store := db.NewStore(sqlDB, key)

	am, err := auth.NewManager(sqlDB, store, strings.Repeat("a", 32), false)
	if err != nil {
		t.Fatalf("auth.NewManager: %v", err)
	}

	cfg := &config.Config{}
	ap := apify.New("")
	nt := ntfy.New("")
	sc := scheduler.New(cfg, store, ap, nt)

	app := New(cfg, store, am, ap, nt, sc)
	return app, app.Routes()
}

func TestHealthz(t *testing.T) {
	_, h := newTestApp(t)
	req := httptest.NewRequest(http.MethodGet, "/healthz", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rec.Code)
	}
	if got := rec.Body.String(); got != "ok" {
		t.Fatalf("body = %q, want %q", got, "ok")
	}
}

func TestSetupGateRedirectsWhenNoUsers(t *testing.T) {
	_, h := newTestApp(t)
	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusSeeOther {
		t.Fatalf("status = %d, want 303", rec.Code)
	}
	if loc := rec.Header().Get("Location"); loc != "/setup" {
		t.Fatalf("Location = %q, want /setup", loc)
	}
}

func TestRequireAuthRedirectsToLogin(t *testing.T) {
	app, h := newTestApp(t)
	hash, err := auth.HashPassword("a-long-enough-password")
	if err != nil {
		t.Fatalf("HashPassword: %v", err)
	}
	if _, err := app.Store.CreateUser(context.Background(), "admin", hash, models.RoleAdmin); err != nil {
		t.Fatalf("CreateUser: %v", err)
	}

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusSeeOther {
		t.Fatalf("status = %d, want 303", rec.Code)
	}
	if loc := rec.Header().Get("Location"); loc != "/login" {
		t.Fatalf("Location = %q, want /login", loc)
	}
}

func TestLoginPageRenders(t *testing.T) {
	app, h := newTestApp(t)
	hash, _ := auth.HashPassword("a-long-enough-password")
	if _, err := app.Store.CreateUser(context.Background(), "admin", hash, models.RoleAdmin); err != nil {
		t.Fatalf("CreateUser: %v", err)
	}
	req := httptest.NewRequest(http.MethodGet, "/login", nil)
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rec.Code)
	}
	if !strings.Contains(rec.Body.String(), "<form") {
		t.Fatalf("body missing <form>")
	}
}

// ============ forward-auth (Authentik) integration ============

// Authentik header names, matching internal/config defaults.
const (
	hdrEmail    = "X-Authentik-Email"
	hdrUsername = "X-Authentik-Username"
	hdrName     = "X-Authentik-Name"
	hdrGroups   = "X-Authentik-Groups"
)

// enableForwardAuth turns on forward-auth trust for the 10.0.0.0/8 range with
// admin group "veola-admins", mirroring a Traefik-in-front deployment.
func enableForwardAuth(t *testing.T, app *App) {
	t.Helper()
	fa, err := auth.NewForwardAuthConfig(hdrUsername, hdrEmail, hdrName, hdrGroups, "veola-admins",
		[]string{"10.0.0.0/8"})
	if err != nil {
		t.Fatalf("NewForwardAuthConfig: %v", err)
	}
	app.Auth.SetForwardAuth(fa)
}

// testClient threads cookies across requests so an scs session survives a
// GET-then-POST flow, and applies a fixed peer address + identity headers.
type testClient struct {
	h          http.Handler
	remoteAddr string
	headers    map[string]string
	cookies    map[string]*http.Cookie
}

func newClient(h http.Handler, remoteAddr string, headers map[string]string) *testClient {
	return &testClient{h: h, remoteAddr: remoteAddr, headers: headers, cookies: map[string]*http.Cookie{}}
}

func (c *testClient) do(method, target string, form url.Values) *httptest.ResponseRecorder {
	var req *http.Request
	if form != nil {
		req = httptest.NewRequest(method, target, strings.NewReader(form.Encode()))
		req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	} else {
		req = httptest.NewRequest(method, target, nil)
	}
	if c.remoteAddr != "" {
		req.RemoteAddr = c.remoteAddr
	}
	for k, v := range c.headers {
		req.Header.Set(k, v)
	}
	for _, ck := range c.cookies {
		req.AddCookie(ck)
	}
	rec := httptest.NewRecorder()
	c.h.ServeHTTP(rec, req)
	for _, ck := range rec.Result().Cookies() {
		c.cookies[ck.Name] = ck
	}
	return rec
}

var csrfRe = regexp.MustCompile(`name="csrf_token" value="([^"]+)"`)

func extractCSRF(t *testing.T, body string) string {
	t.Helper()
	m := csrfRe.FindStringSubmatch(body)
	if m == nil {
		t.Fatal("no csrf_token field in body")
	}
	return m[1]
}

func TestForwardAuthProvisionsAdminFromTrustedProxy(t *testing.T) {
	app, h := newTestApp(t)
	enableForwardAuth(t, app)

	c := newClient(h, "10.0.0.5:5555", map[string]string{
		hdrEmail:    "ada@example.com",
		hdrUsername: "ada",
		hdrGroups:   "users|veola-admins",
	})
	rec := c.do(http.MethodGet, "/", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200 (provisioned dashboard); body: %s", rec.Code, rec.Body.String())
	}
	u, err := app.Store.GetUserByEmail(context.Background(), "ada@example.com")
	if err != nil || u == nil {
		t.Fatalf("GetUserByEmail: u=%v err=%v", u, err)
	}
	if u.Role != models.RoleAdmin {
		t.Errorf("role = %q, want admin (from veola-admins group)", u.Role)
	}
	if u.AuthSource != "forward" {
		t.Errorf("auth_source = %q, want forward", u.AuthSource)
	}
}

func TestForwardAuthUntrustedPeerIgnoresSpoofedHeaders(t *testing.T) {
	app, h := newTestApp(t)
	enableForwardAuth(t, app)

	// Same headers, but the direct peer is NOT in the trusted range: the
	// headers must be ignored and no user provisioned.
	c := newClient(h, "203.0.113.9:5555", map[string]string{
		hdrEmail:    "mallory@example.com",
		hdrUsername: "mallory",
		hdrGroups:   "veola-admins",
	})
	rec := c.do(http.MethodGet, "/", nil)
	if rec.Code != http.StatusSeeOther {
		t.Fatalf("status = %d, want 303 (no trust, setup gate)", rec.Code)
	}
	if loc := rec.Header().Get("Location"); loc != "/setup" {
		t.Fatalf("Location = %q, want /setup", loc)
	}
	if u, _ := app.Store.GetUserByEmail(context.Background(), "mallory@example.com"); u != nil {
		t.Fatalf("spoofed header provisioned a user: %+v", u)
	}
}

func TestForwardAuthReSyncsRoleOnEveryRequest(t *testing.T) {
	app, h := newTestApp(t)
	enableForwardAuth(t, app)

	admin := newClient(h, "10.0.0.5:5555", map[string]string{
		hdrEmail:  "bea@example.com",
		hdrGroups: "veola-admins",
	})
	if rec := admin.do(http.MethodGet, "/", nil); rec.Code != http.StatusOK {
		t.Fatalf("first request status = %d, want 200", rec.Code)
	}
	u, _ := app.Store.GetUserByEmail(context.Background(), "bea@example.com")
	if u == nil || u.Role != models.RoleAdmin {
		t.Fatalf("after admin login, role = %v, want admin", u)
	}

	// IdP later drops the admin group: the next request must downgrade the role.
	demoted := newClient(h, "10.0.0.5:5555", map[string]string{
		hdrEmail:  "bea@example.com",
		hdrGroups: "users",
	})
	if rec := demoted.do(http.MethodGet, "/", nil); rec.Code != http.StatusOK {
		t.Fatalf("second request status = %d, want 200", rec.Code)
	}
	u, _ = app.Store.GetUserByEmail(context.Background(), "bea@example.com")
	if u == nil || u.Role != models.RoleUser {
		t.Fatalf("after group drop, role = %v, want user", u)
	}
}

func TestForwardAuthEmailPrefsRoundTrip(t *testing.T) {
	app, h := newTestApp(t)
	enableForwardAuth(t, app)

	// A forward-auth session authenticates without local login; carry its
	// cookie + CSRF token into the POST.
	c := newClient(h, "10.0.0.5:5555", map[string]string{
		hdrEmail:  "cleo@example.com",
		hdrGroups: "users",
	})
	rec := c.do(http.MethodGet, "/settings", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("GET /settings = %d, want 200", rec.Code)
	}
	token := extractCSRF(t, rec.Body.String())

	provisioned, _ := app.Store.GetUserByEmail(context.Background(), "cleo@example.com")
	if provisioned == nil {
		t.Fatal("forward user not provisioned by GET /settings")
	}

	// A forward user can toggle opt-ins, but a form that tries to change the
	// email must be ignored: the address is the Authentik match key, so
	// changing it here would orphan the row on the next sign-in.
	form := url.Values{
		"csrf_token":          {token},
		"email":               {"cleo+spoofed@example.com"},
		"email_deal_alerts":   {"1"},
		"email_weekly_digest": {"1"},
	}
	rec = c.do(http.MethodPost, "/settings/email", form)
	if rec.Code != http.StatusOK {
		t.Fatalf("POST /settings/email = %d, want 200; body: %s", rec.Code, rec.Body.String())
	}

	// Email is unchanged (still the IdP address), so the row still re-matches.
	u, err := app.Store.GetUserByEmail(context.Background(), "cleo@example.com")
	if err != nil || u == nil {
		t.Fatalf("forward user orphaned: GetUserByEmail(IdP addr) u=%v err=%v", u, err)
	}
	if u.ID != provisioned.ID {
		t.Errorf("re-matched a different row: id %d != %d", u.ID, provisioned.ID)
	}
	if u.Email != "cleo@example.com" {
		t.Errorf("email = %q, want the unchanged IdP address cleo@example.com", u.Email)
	}
	if !u.EmailDealAlerts || !u.EmailWeeklyDigest {
		t.Errorf("opt-ins = (deal:%v digest:%v), want both true", u.EmailDealAlerts, u.EmailWeeklyDigest)
	}
	// The user appears in the deal-alert recipient list under their IdP address.
	recips, err := app.Store.UsersWithDealAlerts(context.Background())
	if err != nil {
		t.Fatalf("UsersWithDealAlerts: %v", err)
	}
	if !containsEmail(recips, "cleo@example.com") {
		t.Errorf("deal-alert recipients %v missing cleo", recips)
	}
}

func containsEmail(us []models.User, email string) bool {
	for _, u := range us {
		if u.Email == email {
			return true
		}
	}
	return false
}