package service

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"time"
)

// ChatGPTService ChatGPT API 服务
type ChatGPTService struct {
	client  *http.Client
	baseURL string
}

// NewChatGPTService 创建 ChatGPT 服务
func NewChatGPTService() *ChatGPTService {
	return &ChatGPTService{
		client: &http.Client{
			Timeout: 30 * time.Second,
		},
		baseURL: "https://chatgpt.com/backend-api",
	}
}

// SubscriptionInfo 订阅信息
type SubscriptionInfo struct {
	SeatsInUse    int       `json:"seats_in_use"`
	SeatsEntitled int       `json:"seats_entitled"`
	ActiveStart   time.Time `json:"active_start"`
	ActiveUntil   time.Time `json:"active_until"`
	IsValid       bool      `json:"is_valid"`
}

// subscriptionResponse ChatGPT API 响应结构
type subscriptionResponse struct {
	SeatsInUse    int    `json:"seats_in_use"`
	SeatsEntitled int    `json:"seats_entitled"`
	ActiveStart   string `json:"active_start"`
	ActiveUntil   string `json:"active_until"`
}

// GetSubscription 获取订阅信息
func (s *ChatGPTService) GetSubscription(teamAccountID, authToken string) (*SubscriptionInfo, error) {
	url := fmt.Sprintf("%s/subscriptions?account_id=%s", s.baseURL, teamAccountID)

	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}

	// 设置请求头
	req.Header.Set("Authorization", authToken)
	req.Header.Set("chatgpt-account-id", teamAccountID)
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36")

	resp, err := s.client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}

	// 检查响应状态码
	if resp.StatusCode != http.StatusOK {
		return &SubscriptionInfo{IsValid: false}, nil
	}

	var subResp subscriptionResponse
	if err := json.Unmarshal(body, &subResp); err != nil {
		return &SubscriptionInfo{IsValid: false}, nil
	}

	// 解析时间
	info := &SubscriptionInfo{
		SeatsInUse:    subResp.SeatsInUse,
		SeatsEntitled: subResp.SeatsEntitled,
		IsValid:       true,
	}

	if subResp.ActiveStart != "" {
		if t, err := time.Parse(time.RFC3339, subResp.ActiveStart); err == nil {
			info.ActiveStart = t
		}
	}
	if subResp.ActiveUntil != "" {
		if t, err := time.Parse(time.RFC3339, subResp.ActiveUntil); err == nil {
			info.ActiveUntil = t
		}
	}

	return info, nil
}

// InviteRequest 邀请请求结构
type InviteRequest struct {
	EmailAddresses []string `json:"email_addresses"`
	Role           string   `json:"role"`
	ResendEmails   bool     `json:"resend_emails"`
}

// InviteResponse 邀请响应
type InviteResponse struct {
	Success bool   `json:"success"`
	Message string `json:"message,omitempty"`
	RawBody string `json:"-"`
}

// SendInvite 发送邀请到 ChatGPT Team
func (s *ChatGPTService) SendInvite(teamAccountID, authToken, email string) (*InviteResponse, error) {
	url := fmt.Sprintf("%s/accounts/%s/invites", s.baseURL, teamAccountID)

	// 构建请求体
	reqBody := InviteRequest{
		EmailAddresses: []string{email},
		Role:           "standard-user",
		ResendEmails:   true,
	}

	bodyBytes, err := json.Marshal(reqBody)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal request: %w", err)
	}

	req, err := http.NewRequest("POST", url, bytes.NewBuffer(bodyBytes))
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}

	// 设置请求头
	req.Header.Set("Authorization", authToken)
	req.Header.Set("chatgpt-account-id", teamAccountID)
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36")

	resp, err := s.client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}

	// 检查响应状态码
	if resp.StatusCode >= 200 && resp.StatusCode < 300 {
		return &InviteResponse{
			Success: true,
			Message: "Invitation sent successfully",
			RawBody: string(body),
		}, nil
	}

	// 解析错误响应
	return &InviteResponse{
		Success: false,
		Message: fmt.Sprintf("API returned status %d: %s", resp.StatusCode, string(body)),
		RawBody: string(body),
	}, nil
}

// RemoveMemberResponse 移除成员响应
type RemoveMemberResponse struct {
	Success bool   `json:"success"`
	Message string `json:"message,omitempty"`
	RawBody string `json:"-"`
}

// RemoveMember 从 ChatGPT Team 移除成员
func (s *ChatGPTService) RemoveMember(teamAccountID, authToken, email string) (*RemoveMemberResponse, error) {
	url := fmt.Sprintf("%s/accounts/%s/invites", s.baseURL, teamAccountID)

	// 构建请求体 - 只需要邮箱
	reqBody := map[string]string{
		"email_address": email,
	}

	bodyBytes, err := json.Marshal(reqBody)
	if err != nil {
		return nil, fmt.Errorf("failed to marshal request: %w", err)
	}

	req, err := http.NewRequest("DELETE", url, bytes.NewBuffer(bodyBytes))
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}

	// 设置请求头
	req.Header.Set("Authorization", authToken)
	req.Header.Set("chatgpt-account-id", teamAccountID)
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36")

	resp, err := s.client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to send request: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}

	// 检查响应状态码
	if resp.StatusCode >= 200 && resp.StatusCode < 300 {
		return &RemoveMemberResponse{
			Success: true,
			Message: "Member removed successfully",
			RawBody: string(body),
		}, nil
	}

	// 解析错误响应
	return &RemoveMemberResponse{
		Success: false,
		Message: fmt.Sprintf("API returned status %d: %s", resp.StatusCode, string(body)),
		RawBody: string(body),
	}, nil
}