package ragflow

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"strings"

	"github.com/gogf/gf/v2/frame/g"
	"github.com/gogf/gf/v2/net/gclient"
)

var (
	// globalClient 全局 RAGFlow 客户端（单例，自动初始化）
	globalClient *Client
)

// init 包初始化时自动创建全局客户端
func init() {
	ctx := context.Background()

	// 读取配置
	baseURL, apiKey := loadConfig(ctx)

	// 如果配置不完整，跳过初始化
	if baseURL == "" || apiKey == "" {
		g.Log().Warning(ctx, "⚠️  RAGFlow 配置未找到，请在项目 config.yml 中添加 ragflow.base_url 和 ragflow.api_key")
		return
	}

	// 初始化全局客户端
	httpClient := gclient.New()
	httpClient.SetHeader("Authorization", fmt.Sprintf("Bearer %s", apiKey))
	httpClient.SetHeader("Content-Type", "application/json")

	globalClient = &Client{
		BaseURL:    strings.TrimSuffix(baseURL, "/"),
		APIKey:     apiKey,
		HTTPClient: httpClient,
	}

	g.Log().Infof(ctx, "✅ RAGFlow 全局客户端初始化成功: baseURL=%s", baseURL)
}

// loadConfig 从配置文件加载 RAGFlow 配置
func loadConfig(ctx context.Context) (baseURL, apiKey string) {
	// 使用 GoFrame 全局配置（从项目的 config.yml 读取）
	baseURL = g.Cfg().MustGet(ctx, "ragflow.base_url", "").String()
	apiKey = g.Cfg().MustGet(ctx, "ragflow.api_key", "").String()

	return baseURL, apiKey
}

// GetGlobalClient 获取全局客户端
// 使用示例：client := ragflow.GetGlobalClient()
func GetGlobalClient() *Client {
	return globalClient
}

// Client RAGFlow API 客户端
type Client struct {
	BaseURL    string
	APIKey     string
	HTTPClient *gclient.Client // HTTP 客户端
}

// CommonResponse 通用响应结构
type CommonResponse struct {
	Code    int         `json:"code"`
	Message string      `json:"message"`
	Data    interface{} `json:"data,omitempty"`
}

// IsSuccess 检查响应是否成功
func (r *CommonResponse) IsSuccess() bool {
	return r.Code == 0
}

// request 发送 HTTP 请求
func (c *Client) request(ctx context.Context, method, path string, body interface{}, result interface{}) error {
	fullURL := c.BaseURL + path

	var reqBody io.Reader
	if body != nil {
		jsonData, err := json.Marshal(body)
		if err != nil {
			return fmt.Errorf("marshal request body failed: %w", err)
		}
		reqBody = strings.NewReader(string(jsonData))
	}

	var resp *gclient.Response
	var err error

	switch method {
	case "GET":
		resp, err = c.HTTPClient.Get(ctx, fullURL)
	case "POST":
		resp, err = c.HTTPClient.Post(ctx, fullURL, reqBody)
	case "PUT":
		resp, err = c.HTTPClient.Put(ctx, fullURL, reqBody)
	case "DELETE":
		resp, err = c.HTTPClient.Delete(ctx, fullURL, reqBody)
	default:
		return fmt.Errorf("unsupported method: %s", method)
	}

	if err != nil {
		return fmt.Errorf("http request failed: %w", err)
	}
	defer resp.Close()

	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("http request failed with status: %d", resp.StatusCode)
	}

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

	if err := json.Unmarshal(respBody, result); err != nil {
		return fmt.Errorf("unmarshal response failed: %w", err)
	}

	return nil
}

// buildQueryString 构建查询字符串
func buildQueryString(params map[string]interface{}) string {
	if len(params) == 0 {
		return ""
	}

	var parts []string
	for k, v := range params {
		parts = append(parts, fmt.Sprintf("%s=%v", url.QueryEscape(k), url.QueryEscape(fmt.Sprintf("%v", v))))
	}
	return strings.Join(parts, "&")
}