package httpapi

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

	"github.com/golang-jwt/jwt/v5"
)

const (
	testJWTSecret = "test-secret-32-bytes-long-abcdef"
	testIssuer    = "https://auth.test.local"
)

func signTestJWT(t *testing.T, claims jwt.MapClaims) string {
	t.Helper()
	tok := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
	s, err := tok.SignedString([]byte(testJWTSecret))
	if err != nil {
		t.Fatalf("sign jwt: %v", err)
	}
	return s
}

func newJWTTestServer(t *testing.T) (*Server, string) {
	t.Helper()
	srv, err := New(Options{
		SeedDemo:       true,
		BundleSeedHex:  testBundleSeed,
		JWTSecret:      testJWTSecret,
		AuthIssuer:     testIssuer,
		AuthPortalURL:  "https://portal.test.local",
		AuthRequired:   true,
		PortalTenantID: "", // filled after DemoIDs
	})
	if err != nil {
		t.Fatal(err)
	}
	tenant, _, _, _, _ := srv.Store().DemoIDs()
	// Override tenant to match seed.
	srv.portalTenantID = tenant
	return srv, tenant
}

func TestAuthJWTAcceptedWithBGPApp(t *testing.T) {
	srv, _ := newJWTTestServer(t)
	defer srv.Close()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	token := signTestJWT(t, jwt.MapClaims{
		"iss":         testIssuer,
		"sub":         "user-1",
		"email":       "user@test.local",
		"apps":        []string{"bgp"},
		"permissions": []string{"bgp:modules:read"},
		"exp":         time.Now().Add(time.Hour).Unix(),
	})

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/modules", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusOK {
		b, _ := io.ReadAll(resp.Body)
		t.Fatalf("status=%d body=%s", resp.StatusCode, b)
	}
}

func TestAuthJWTRejectedOnWrongIssuer(t *testing.T) {
	srv, _ := newJWTTestServer(t)
	defer srv.Close()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	token := signTestJWT(t, jwt.MapClaims{
		"iss":  "https://other.example.com",
		"sub":  "user-1",
		"apps": []string{"bgp"},
		"exp":  time.Now().Add(time.Hour).Unix(),
	})

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/modules", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusUnauthorized {
		t.Fatalf("status=%d want 401", resp.StatusCode)
	}
}

func TestAuthJWTRejectedWhenBGPAppMissing(t *testing.T) {
	srv, _ := newJWTTestServer(t)
	defer srv.Close()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	token := signTestJWT(t, jwt.MapClaims{
		"iss":  testIssuer,
		"sub":  "user-1",
		"apps": []string{"cfdm", "portal"},
		"exp":  time.Now().Add(time.Hour).Unix(),
	})

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/modules", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusForbidden {
		t.Fatalf("status=%d want 403", resp.StatusCode)
	}
}

func TestAuthJWTIsAdminBypassesPermissions(t *testing.T) {
	srv, _ := newJWTTestServer(t)
	defer srv.Close()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	token := signTestJWT(t, jwt.MapClaims{
		"iss":      testIssuer,
		"sub":      "admin-1",
		"apps":     []string{"bgp"},
		"is_admin": true,
		"exp":      time.Now().Add(time.Hour).Unix(),
	})

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/api-keys", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusOK {
		b, _ := io.ReadAll(resp.Body)
		t.Fatalf("status=%d body=%s", resp.StatusCode, b)
	}
}

func TestAuthJWTMissingPermissionRejected(t *testing.T) {
	srv, _ := newJWTTestServer(t)
	defer srv.Close()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	token := signTestJWT(t, jwt.MapClaims{
		"iss":         testIssuer,
		"sub":         "user-1",
		"apps":        []string{"bgp"},
		"permissions": []string{"bgp:modules:read"},
		"exp":         time.Now().Add(time.Hour).Unix(),
	})

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/api-keys", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusForbidden {
		t.Fatalf("status=%d want 403", resp.StatusCode)
	}
}

func TestAuthJWTTenantFromClaimWithoutEnv(t *testing.T) {
	srv, err := New(Options{
		SeedDemo:      true,
		BundleSeedHex: testBundleSeed,
		JWTSecret:     testJWTSecret,
		AuthIssuer:    testIssuer,
		AuthPortalURL: "https://portal.test.local",
		AuthRequired:  true,
		// No PortalTenantID — must come from JWT claim.
	})
	if err != nil {
		t.Fatal(err)
	}
	defer srv.Close()
	tenant, _, _, _, _ := srv.Store().DemoIDs()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	token := signTestJWT(t, jwt.MapClaims{
		"iss":           testIssuer,
		"sub":           "user-1",
		"apps":          []string{"bgp"},
		"permissions":   []string{"bgp:modules:read"},
		"bgp_tenant_id": tenant,
		"exp":           time.Now().Add(time.Hour).Unix(),
	})

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/modules", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusOK {
		b, _ := io.ReadAll(resp.Body)
		t.Fatalf("status=%d body=%s", resp.StatusCode, b)
	}
}

func TestAuthJWTRejectedWhenTenantMissing(t *testing.T) {
	srv, err := New(Options{
		SeedDemo:      true,
		BundleSeedHex: testBundleSeed,
		JWTSecret:     testJWTSecret,
		AuthIssuer:    testIssuer,
		AuthPortalURL: "https://portal.test.local",
		AuthRequired:  true,
	})
	if err != nil {
		t.Fatal(err)
	}
	defer srv.Close()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	token := signTestJWT(t, jwt.MapClaims{
		"iss":  testIssuer,
		"sub":  "user-1",
		"apps": []string{"bgp"},
		"exp":  time.Now().Add(time.Hour).Unix(),
	})

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/modules", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusServiceUnavailable {
		t.Fatalf("status=%d want 503", resp.StatusCode)
	}
}

func TestAuthConfigPublic(t *testing.T) {
	srv, _ := newJWTTestServer(t)
	defer srv.Close()

	ts := httptest.NewServer(srv.Handler())
	defer ts.Close()

	req, _ := http.NewRequest(http.MethodGet, ts.URL+"/v1/auth/config", nil)
	resp, err := ts.Client().Do(req)
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusOK {
		b, _ := io.ReadAll(resp.Body)
		t.Fatalf("status=%d body=%s", resp.StatusCode, b)
	}
}

func TestHasPermissionSupersets(t *testing.T) {
	cases := []struct {
		name    string
		granted []string
		want    string
		ok      bool
	}{
		{"exact-read", []string{"bgp:modules:read"}, "bgp:modules:read", true},
		{"write-covers-read", []string{"bgp:modules:write"}, "bgp:modules:read", true},
		{"admin-covers-write", []string{"bgp:modules:admin"}, "bgp:modules:write", true},
		{"read-does-not-cover-write", []string{"bgp:modules:read"}, "bgp:modules:write", false},
		{"different-section", []string{"bgp:network:admin"}, "bgp:modules:read", false},
		{"empty-granted", nil, "bgp:modules:read", false},
		{"malformed-required", []string{"bgp:modules:admin"}, "bgp:modules", false},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			if got := HasPermission(tc.granted, tc.want); got != tc.ok {
				t.Fatalf("HasPermission(%v, %q) = %v, want %v", tc.granted, tc.want, got, tc.ok)
			}
		})
	}
}