package register

import (
	"bytes"
	"encoding/json"
	"fmt"
	"math/rand"
	"net/http"
	"net/url"
	"strings"
	"time"

	"codex-pool/internal/client"
	"codex-pool/internal/mail"
)

// ChatGPTReg ChatGPT 注册器
type ChatGPTReg struct {
	Proxy                string
	Client               *client.TLSClient
	AuthSessionLoggingID string
	OAIDid               string
	CSRFToken            string
	AuthorizeURL         string
	AccessToken          string
}

// Result 注册结果
type Result struct {
	Email       string `json:"email"`
	Password    string `json:"password"`
	Name        string `json:"name"`
	AccessToken string `json:"access_token"`
}

// New 创建注册器
func New(proxy string) (*ChatGPTReg, error) {
	c, err := client.New(proxy)
	if err != nil {
		return nil, err
	}

	return &ChatGPTReg{
		Proxy:                proxy,
		Client:               c,
		AuthSessionLoggingID: GenerateUUID(),
	}, nil
}

// InitSession 初始化会话
func (r *ChatGPTReg) InitSession() error {
	resp, err := r.Client.Get("https://chatgpt.com")
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		return fmt.Errorf("初始化失败，状态码: %d", resp.StatusCode)
	}

	r.OAIDid = r.Client.GetCookie("https://chatgpt.com", "oai-did")

	csrfCookie := r.Client.GetCookie("https://chatgpt.com", "__Host-next-auth.csrf-token")
	if csrfCookie != "" {
		decoded, err := url.QueryUnescape(csrfCookie)
		if err == nil {
			parts := strings.Split(decoded, "|")
			if len(parts) > 0 {
				r.CSRFToken = parts[0]
			}
		}
	}

	if r.CSRFToken == "" {
		return fmt.Errorf("无法获取 CSRF token")
	}

	loginURL := fmt.Sprintf("https://chatgpt.com/auth/login?openaicom-did=%s", r.OAIDid)
	loginResp, err := r.Client.Get(loginURL)
	if err != nil {
		return err
	}
	defer loginResp.Body.Close()

	return nil
}

// GetAuthorizeURL 获取授权 URL
func (r *ChatGPTReg) GetAuthorizeURL(email string) error {
	loginURL := fmt.Sprintf(
		"https://chatgpt.com/api/auth/signin/openai?prompt=login&ext-oai-did=%s&auth_session_logging_id=%s&screen_hint=login_or_signup&login_hint=%s",
		r.OAIDid,
		r.AuthSessionLoggingID,
		url.QueryEscape(email),
	)

	data := url.Values{}
	data.Set("callbackUrl", "https://chatgpt.com/")
	data.Set("csrfToken", r.CSRFToken)
	data.Set("json", "true")

	req, err := http.NewRequest("POST", loginURL, strings.NewReader(data.Encode()))
	if err != nil {
		return err
	}
	req.Header.Set("Origin", "https://chatgpt.com")
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	resp, err := r.Client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	var result map[string]interface{}
	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil {
		return err
	}

	if authURL, ok := result["url"].(string); ok && strings.Contains(authURL, "auth.openai.com") {
		r.AuthorizeURL = authURL
		return nil
	}

	return fmt.Errorf("无法获取授权 URL")
}

// StartAuthorize 开始授权流程
func (r *ChatGPTReg) StartAuthorize() error {
	resp, err := r.Client.Get(r.AuthorizeURL)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	finalURL := resp.Request.URL.String()
	if strings.Contains(finalURL, "create-account") || strings.Contains(finalURL, "log-in") {
		return nil
	}

	return fmt.Errorf("授权流程启动失败")
}

// Register 注册账户
func (r *ChatGPTReg) Register(email, password string) error {
	payload := map[string]string{
		"password": password,
		"username": email,
	}
	jsonData, _ := json.Marshal(payload)

	req, err := http.NewRequest("POST", "https://auth.openai.com/api/accounts/user/register", bytes.NewReader(jsonData))
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Origin", "https://auth.openai.com")

	resp, err := r.Client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		body, _ := client.ReadBodyString(resp)
		return fmt.Errorf("注册失败，状态码: %d, 响应: %s", resp.StatusCode, truncateStr(body, 200))
	}

	return nil
}

// SendVerificationEmail 发送验证邮件
func (r *ChatGPTReg) SendVerificationEmail() error {
	resp, err := r.Client.Get("https://auth.openai.com/api/accounts/email-otp/send")
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		return fmt.Errorf("发送验证邮件失败，状态码: %d", resp.StatusCode)
	}

	return nil
}

// ValidateOTP 验证 OTP
func (r *ChatGPTReg) ValidateOTP(code string) error {
	payload := map[string]string{"code": code}
	jsonData, _ := json.Marshal(payload)

	req, err := http.NewRequest("POST", "https://auth.openai.com/api/accounts/email-otp/validate", bytes.NewReader(jsonData))
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Origin", "https://auth.openai.com")

	resp, err := r.Client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		return fmt.Errorf("OTP 验证失败，状态码: %d", resp.StatusCode)
	}

	return nil
}

// CreateAccount 创建账户
func (r *ChatGPTReg) CreateAccount(name, birthdate string) error {
	payload := map[string]string{
		"name":      name,
		"birthdate": birthdate,
	}
	jsonData, _ := json.Marshal(payload)

	req, err := http.NewRequest("POST", "https://auth.openai.com/api/accounts/create_account", bytes.NewReader(jsonData))
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Origin", "https://auth.openai.com")

	resp, err := r.Client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		return fmt.Errorf("创建账户失败，状态码: %d", resp.StatusCode)
	}

	var result map[string]interface{}
	if err := json.NewDecoder(resp.Body).Decode(&result); err == nil {
		if continueURL, ok := result["continue_url"].(string); ok && continueURL != "" {
			contResp, err := r.Client.Get(continueURL)
			if err == nil {
				contResp.Body.Close()
			}
		}
	}

	return nil
}

// GetSessionToken 获取 access token
func (r *ChatGPTReg) GetSessionToken() error {
	resp, err := r.Client.Get("https://chatgpt.com/api/auth/session")
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		return fmt.Errorf("获取 session 失败，状态码: %d", resp.StatusCode)
	}

	var result map[string]interface{}
	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil {
		return err
	}

	if token, ok := result["accessToken"].(string); ok {
		r.AccessToken = token
		return nil
	}

	return fmt.Errorf("响应中没有 accessToken")
}

// Run 完整的注册流程
func Run(email, password, name, birthdate, proxy string) (*ChatGPTReg, error) {
	return RunWithRetry(email, password, name, birthdate, proxy, 3)
}

// RunWithRetry 带重试的注册流程
// 当验证码获取超过5秒，就换新邮箱重新注册
func RunWithRetry(email, password, name, birthdate, proxy string, maxRetries int) (*ChatGPTReg, error) {
	for attempt := 0; attempt < maxRetries; attempt++ {
		if attempt > 0 {
			// 重试时生成新邮箱
			email = mail.GenerateEmail()
			password = GeneratePassword()
			fmt.Printf("  [Retry %d] New email: %s\n", attempt, email)
		}

		reg, err := runOnce(email, password, name, birthdate, proxy)
		if err == nil {
			return reg, nil
		}

		// 如果不是验证码超时错误，直接返回
		if !strings.Contains(err.Error(), "验证码获取超时") {
			return nil, err
		}

		fmt.Printf("  [!] OTP timeout, retrying with new email...\n")
	}

	return nil, fmt.Errorf("注册失败: 已重试 %d 次", maxRetries)
}

// runOnce 执行一次注册流程（使用短超时获取验证码）
func runOnce(email, password, name, birthdate, proxy string) (*ChatGPTReg, error) {
	reg, err := New(proxy)
	if err != nil {
		return nil, err
	}

	// 初始化
	if err := reg.InitSession(); err != nil {
		return nil, fmt.Errorf("初始化失败: %v", err)
	}
	if err := reg.GetAuthorizeURL(email); err != nil {
		return nil, fmt.Errorf("获取授权URL失败: %v", err)
	}
	if err := reg.StartAuthorize(); err != nil {
		return nil, fmt.Errorf("启动授权失败: %v", err)
	}

	// 注册
	if err := reg.Register(email, password); err != nil {
		return nil, fmt.Errorf("注册失败: %v", err)
	}
	if err := reg.SendVerificationEmail(); err != nil {
		return nil, fmt.Errorf("发送邮件失败: %v", err)
	}

	// 先用5秒超时尝试获取验证码
	otpCode, err := mail.GetVerificationCode(email, 5*time.Second)
	if err != nil {
		// 5秒内没获取到，再等120秒（总共等待更多时间）
		otpCode, err = mail.GetVerificationCode(email, 120*time.Second)
		if err != nil {
			return nil, fmt.Errorf("验证码获取超时")
		}
	}

	if err := reg.ValidateOTP(otpCode); err != nil {
		return nil, fmt.Errorf("OTP验证失败: %v", err)
	}

	// 创建账户
	if err := reg.CreateAccount(name, birthdate); err != nil {
		return nil, fmt.Errorf("创建账户失败: %v", err)
	}

	// 获取 Token
	_ = reg.GetSessionToken()

	return reg, nil
}

// ==================== 工具函数 ====================

// GenerateName 生成随机姓名
func GenerateName() string {
	firstNames := []string{"James", "John", "Robert", "Michael", "David", "William", "Richard", "Joseph", "Thomas", "Charles"}
	lastNames := []string{"Smith", "Johnson", "Williams", "Brown", "Jones", "Garcia", "Miller", "Davis", "Rodriguez", "Martinez"}
	return firstNames[rand.Intn(len(firstNames))] + " " + lastNames[rand.Intn(len(lastNames))]
}

// GenerateUUID 生成 UUID
func GenerateUUID() string {
	b := make([]byte, 16)
	rand.Read(b)
	b[6] = (b[6] & 0x0f) | 0x40
	b[8] = (b[8] & 0x3f) | 0x80
	return fmt.Sprintf("%x-%x-%x-%x-%x", b[0:4], b[4:6], b[6:8], b[8:10], b[10:16])
}

// GenerateBirthdate 生成随机生日
func GenerateBirthdate() string {
	year := 2000 + rand.Intn(5)
	month := 1 + rand.Intn(12)
	day := 1 + rand.Intn(28)
	return fmt.Sprintf("%d-%02d-%02d", year, month, day)
}

// GeneratePassword 生成随机密码
func GeneratePassword() string {
	const (
		upper   = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
		lower   = "abcdefghijklmnopqrstuvwxyz"
		digits  = "0123456789"
		special = "!@#$%"
	)

	b := make([]byte, 13)
	for i := 0; i < 2; i++ {
		b[i] = upper[rand.Intn(len(upper))]
	}
	for i := 2; i < 10; i++ {
		b[i] = lower[rand.Intn(len(lower))]
	}
	for i := 10; i < 12; i++ {
		b[i] = digits[rand.Intn(len(digits))]
	}
	b[12] = special[rand.Intn(len(special))]

	return string(b)
}

func truncateStr(s string, maxLen int) string {
	if len(s) <= maxLen {
		return s
	}
	return s[:maxLen] + "..."
}