package gateway

import (
	"context"
	"crypto/sha256"
	"database/sql"
	"encoding/hex"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/auth"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/bus"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/config"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/db"
)

// newRefreshEnv 构建一个网关，后端是真实 JWT 服务与真实的
// SQLite refresh 存储，并返回该存储与 DB，使测试能断言
// 持久化了什么。DB 每个测试都隔离在内存中。
func newRefreshEnv(t *testing.T) (*testEnv, *auth.RefreshStore, *sql.DB) {
	t.Helper()
	ctx := context.Background()
	sqlDB, err := db.Open(ctx, ":memory:", nil)
	if err != nil {
		t.Fatalf("open in-memory db: %v", err)
	}
	t.Cleanup(func() { _ = sqlDB.Close() })
	if err := db.MigrateUp(ctx, sqlDB, nil); err != nil {
		t.Fatalf("migrate up: %v", err)
	}
	refresh, err := auth.NewRefreshStore(ctx, sqlDB, nil)
	if err != nil {
		t.Fatalf("new refresh store: %v", err)
	}
	jwt := auth.New(config.AuthConfig{JWTSecret: testSecret})
	b := bus.New()
	cfg := &config.Config{Auth: config.AuthConfig{
		AdminUser:  "admin",
		AdminPass:  "secret",
		JWTSecret:  testSecret,
		RefreshTTL: time.Hour,
	}}
	srv, err := New(cfg, Deps{Auth: jwt, Bus: b, Refresh: refresh})
	if err != nil {
		t.Fatalf("new server: %v", err)
	}
	ts := httptest.NewServer(srv.Handler())
	t.Cleanup(ts.Close)
	return &testEnv{srv: srv, ts: ts, auth: jwt, bus: b}, refresh, sqlDB
}

// decodeData 把 {data: ...} 信封载荷反序列化进 v。
func decodeData(t *testing.T, body []byte, v any) {
	t.Helper()
	env := decodeBody(t, body)
	raw, ok := env["data"]
	if !ok {
		t.Fatalf("response has no data envelope: %s", body)
	}
	if err := json.Unmarshal(raw, v); err != nil {
		t.Fatalf("decode data %s: %v", body, err)
	}
}

// loginRefresh 执行一次管理登录并返回访问令牌与 refresh token。
func loginRefresh(t *testing.T, ts *httptest.Server) (string, string) {
	t.Helper()
	resp, body := doReq(t, http.MethodPost, ts.URL+"/api/v1/auth/login",
		map[string]string{"username": "admin", "password": "secret"}, "")
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("login status = %d, want 200: %s", resp.StatusCode, body)
	}
	var data struct {
		Token        string `json:"token"`
		RefreshToken string `json:"refreshToken"`
		Role         string `json:"role"`
		ExpiresAt    int64  `json:"expiresAt"`
	}
	decodeData(t, body, &data)
	if data.Token == "" || data.ExpiresAt == 0 || data.Role != "owner" {
		t.Fatalf("login payload = %+v, want token/expiresAt/role=owner", data)
	}
	if data.RefreshToken == "" {
		t.Fatalf("login payload has no refreshToken: %s", body)
	}
	return data.Token, data.RefreshToken
}

// postRefresh 用 token 调用 /auth/refresh 并返回状态与响应体。
func postRefresh(t *testing.T, ts *httptest.Server, token string) (int, []byte) {
	t.Helper()
	resp, body := doReq(t, http.MethodPost, ts.URL+"/api/v1/auth/refresh",
		map[string]string{"refreshToken": token}, "")
	return resp.StatusCode, body
}

// wantInvalidGrant 断言 401 与机器可读的 invalid_grant 码。
func wantInvalidGrant(t *testing.T, status int, body []byte) {
	t.Helper()
	if status != http.StatusUnauthorized {
		t.Fatalf("status = %d, want 401: %s", status, body)
	}
	env := decodeBody(t, body)
	var eobj struct {
		Code string `json:"code"`
	}
	if err := json.Unmarshal(env["error"], &eobj); err != nil {
		t.Fatalf("error envelope: %v (%s)", err, body)
	}
	if eobj.Code != "invalid_grant" {
		t.Fatalf("error code = %q, want invalid_grant: %s", eobj.Code, body)
	}
}

func TestLoginReturnsRefreshTokenHashedAtRest(t *testing.T) {
	env, _, sqlDB := newRefreshEnv(t)
	access, refresh := loginRefresh(t, env.ts)

	if _, err := env.auth.Verify(access); err != nil {
		t.Fatalf("access token does not verify: %v", err)
	}
	var hash string
	if err := sqlDB.QueryRowContext(context.Background(),
		"SELECT token_hash FROM refresh_tokens WHERE user_id = 'admin'").Scan(&hash); err != nil {
		t.Fatalf("select token_hash: %v", err)
	}
	if hash == refresh {
		t.Fatal("refresh token stored in plaintext")
	}
	sum := sha256.Sum256([]byte(refresh))
	if want := hex.EncodeToString(sum[:]); hash != want {
		t.Fatalf("stored hash = %q, want %q", hash, want)
	}
}

func TestRefreshRotatesAccessAndRefreshTokens(t *testing.T) {
	env, _, _ := newRefreshEnv(t)
	_, oldRefresh := loginRefresh(t, env.ts)

	status, body := postRefresh(t, env.ts, oldRefresh)
	if status != http.StatusOK {
		t.Fatalf("refresh status = %d, want 200: %s", status, body)
	}
	var data struct {
		Token        string `json:"token"`
		ExpiresAt    int64  `json:"expiresAt"`
		Role         string `json:"role"`
		RefreshToken string `json:"refreshToken"`
	}
	decodeData(t, body, &data)
	if data.Token == "" || data.ExpiresAt == 0 || data.Role != "owner" {
		t.Fatalf("refresh payload = %+v, want token/expiresAt/role", data)
	}
	if data.RefreshToken == "" || data.RefreshToken == oldRefresh {
		t.Fatalf("refresh token not rotated: %q", data.RefreshToken)
	}
	claims, err := env.auth.Verify(data.Token)
	if err != nil {
		t.Fatalf("refreshed access token does not verify: %v", err)
	}
	if claims.Sub != "admin" || claims.Role != auth.RoleOwner {
		t.Fatalf("refreshed claims = %+v, want admin/owner", claims)
	}

	// 出示的 token 是一次性的：重放必须失败。
	status, body = postRefresh(t, env.ts, oldRefresh)
	wantInvalidGrant(t, status, body)

	// 轮换后的 token 有效。
	if status, body = postRefresh(t, env.ts, data.RefreshToken); status != http.StatusOK {
		t.Fatalf("rotate replacement status = %d, want 200: %s", status, body)
	}
}

func TestRefreshRejectsBadGrants(t *testing.T) {
	env, refresh, sqlDB := newRefreshEnv(t)
	ctx := context.Background()

	expired := "expired-token-value"
	sum := sha256.Sum256([]byte(expired))
	if _, err := sqlDB.ExecContext(ctx,
		`INSERT INTO refresh_tokens (id, user_id, role, token_hash, expires_at) VALUES (?, ?, ?, ?, ?)`,
		"seed-expired", "admin", "owner", hex.EncodeToString(sum[:]),
		time.Now().UTC().Add(-time.Minute).Format(time.RFC3339Nano)); err != nil {
		t.Fatalf("seed expired token: %v", err)
	}
	revoked, _, err := refresh.Issue(ctx, "admin", auth.RoleOwner, time.Hour)
	if err != nil {
		t.Fatalf("issue revoked token: %v", err)
	}
	if ok, err := refresh.Revoke(ctx, revoked); err != nil || !ok {
		t.Fatalf("revoke = (%v, %v), want (true, nil)", ok, err)
	}

	cases := map[string]string{
		"empty":   "",
		"garbage": "not-a-real-token",
		"expired": expired,
		"revoked": revoked,
	}
	for name, token := range cases {
		t.Run(name, func(t *testing.T) {
			status, body := postRefresh(t, env.ts, token)
			wantInvalidGrant(t, status, body)
		})
	}
}

func TestLogoutRevokesRefreshToken(t *testing.T) {
	env, _, _ := newRefreshEnv(t)
	_, refreshToken := loginRefresh(t, env.ts)

	resp, body := doReq(t, http.MethodPost, env.ts.URL+"/api/v1/auth/logout",
		map[string]string{"refreshToken": refreshToken}, "")
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("logout status = %d, want 200: %s", resp.StatusCode, body)
	}
	var data struct {
		Revoked bool `json:"revoked"`
	}
	decodeData(t, body, &data)
	if !data.Revoked {
		t.Fatalf("logout revoked = false, want true: %s", body)
	}
	if status, body := postRefresh(t, env.ts, refreshToken); status != http.StatusUnauthorized {
		t.Fatalf("refresh after logout status = %d, want 401: %s", status, body)
	}

	// 登出是幂等的：第二次调用报告 revoked=false，而不是错误。
	resp, body = doReq(t, http.MethodPost, env.ts.URL+"/api/v1/auth/logout",
		map[string]string{"refreshToken": refreshToken}, "")
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("second logout status = %d, want 200: %s", resp.StatusCode, body)
	}
	decodeData(t, body, &data)
	if data.Revoked {
		t.Fatalf("second logout revoked = true, want false")
	}
}

func TestLogoutWithAccessTokenRevokesUserGrants(t *testing.T) {
	env, _, _ := newRefreshEnv(t)
	access, refreshToken := loginRefresh(t, env.ts)

	resp, body := doReq(t, http.MethodPost, env.ts.URL+"/api/v1/auth/logout", nil, access)
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("logout status = %d, want 200: %s", resp.StatusCode, body)
	}
	var data struct {
		Revoked      bool  `json:"revoked"`
		RevokedCount int64 `json:"revokedCount"`
	}
	decodeData(t, body, &data)
	if !data.Revoked || data.RevokedCount != 1 {
		t.Fatalf("logout payload = %+v, want revoked with 1 grant", data)
	}
	if status, body := postRefresh(t, env.ts, refreshToken); status != http.StatusUnauthorized {
		t.Fatalf("refresh after access-token logout status = %d, want 401: %s", status, body)
	}
}

func TestRotateJWTInvalidatesRefreshTokens(t *testing.T) {
	env, _, _ := newRefreshEnv(t)
	_, refreshToken := loginRefresh(t, env.ts)

	owner := env.token(t, auth.RoleOwner)
	resp, body := doReq(t, http.MethodPost, env.ts.URL+"/api/v1/admin/system/rotate-jwt",
		map[string]string{"newSecret": "a-brand-new-jwt-secret-at-least-32-chars"}, owner)
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("rotate-jwt status = %d, want 200: %s", resp.StatusCode, body)
	}
	var data struct {
		Rotated              bool  `json:"rotated"`
		RefreshTokensRevoked int64 `json:"refreshTokensRevoked"`
	}
	decodeData(t, body, &data)
	if !data.Rotated || data.RefreshTokensRevoked != 1 {
		t.Fatalf("rotate-jwt payload = %+v, want rotated with 1 refresh token revoked", data)
	}
	if status, body := postRefresh(t, env.ts, refreshToken); status != http.StatusUnauthorized {
		t.Fatalf("refresh after rotate-jwt status = %d, want 401: %s", status, body)
	}
}