✨ feat(core): 初始化 Bot 命令处理服务器

- 基于 Gin 框架搭建 HTTP 服务，接收并处理 Bot 命令请求
- 实现插件化命令系统，支持通过 Plugin 接口扩展新命令
- 内置菜单、启用/禁用、时间查询等基础命令
- 新增图片生成插件，对接 OpenAI Images API
- 支持管理员权限控制、命令动态启禁用
- 提供完整配置管理（.env）与 Docker 部署方案

plugins/image/image.go

@@ -0,0 +1,211 @@
+package image
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"log"
+	"ncatbot-command-server/command"
+	"ncatbot-command-server/config"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/go-resty/resty/v2"
+)
+
+// Plugin 图片生成插件
+type Plugin struct{}
+
+var imgClient *resty.Client
+var uploadClient *resty.Client
+
+func init() {
+	command.RegisterPlugin(&Plugin{})
+}
+
+// Name 实现 Plugin 接口
+func (p *Plugin) Name() string {
+	return "生图"
+}
+
+// Description 实现 Plugin 接口
+func (p *Plugin) Description() string {
+	return "根据描述生成图片"
+}
+
+// Usage 实现 Plugin 接口
+func (p *Plugin) Usage() string {
+	return "生图 <描述>"
+}
+
+// Init 实现 PluginWithInit 接口
+func (p *Plugin) Init() {
+	cfg := config.Cfg
+	imgClient = newHTTPClient(cfg, true)
+	uploadClient = newHTTPClient(cfg, false)
+	os.MkdirAll(cfg.ImageOutputDir, 0755)
+}
+
+// Run 实现 Plugin 接口
+func (p *Plugin) Run(req *command.Req) command.Resp {
+	if req.Content == "" {
+		return command.Resp{Reply: "请输入生图描述，例如：生图 一只猫"}
+	}
+
+	url, err := genImage(req.Content)
+	if err != nil {
+		log.Printf("gen image error: %v", err)
+		return command.Resp{Reply: "生成失败: " + err.Error()}
+	}
+
+	return command.Resp{
+		Messages: []command.Message{
+			{Type: command.MsgTypeImage, URL: url},
+		},
+	}
+}
+
+func newHTTPClient(cfg config.Config, withAuth bool) *resty.Client {
+	c := resty.New().
+		SetTimeout(time.Duration(cfg.RequestTimeout) * time.Second)
+	if withAuth {
+		c.SetHeader("Content-Type", "application/json").
+			SetHeader("Authorization", "Bearer "+cfg.OpenAIAPIKey)
+	}
+	if cfg.Proxy != "" {
+		c.SetProxy(cfg.Proxy)
+	}
+	return c
+}
+
+// --- API Response types ---
+
+type OpenAIImageResp struct {
+	Created int64 `json:"created"`
+	Data    []struct {
+		URL           string `json:"url"`
+		B64JSON       string `json:"b64_json"`
+		RevisedPrompt string `json:"revised_prompt"`
+	} `json:"data"`
+}
+
+type UploadResp struct {
+	Code int    `json:"code"`
+	Msg  string `json:"msg"`
+	Data struct {
+		Files []string `json:"files"`
+		Path  string   `json:"path"`
+	} `json:"data"`
+}
+
+// --- Pipeline ---
+
+func genImage(prompt string) (string, error) {
+	cfg := config.Cfg
+	if cfg.OpenAIAPIKey == "" {
+		return "", errors.New("OPENAI_API_KEY not set")
+	}
+
+	b64, err := requestImage(prompt)
+	if err != nil {
+		return "", err
+	}
+
+	filePath, err := saveImage(b64)
+	if err != nil {
+		return "", err
+	}
+
+	remotePath, err := uploadImage(filePath)
+	if err != nil {
+		return "", fmt.Errorf("upload failed: %w", err)
+	}
+
+	os.Remove(filePath)
+	return remotePath, nil
+}
+
+func requestImage(prompt string) (string, error) {
+	cfg := config.Cfg
+
+	var result OpenAIImageResp
+	resp, err := imgClient.R().
+		SetBody(map[string]any{
+			"model":           cfg.OpenAIModel,
+			"prompt":          prompt,
+			"n":               cfg.ImageCount,
+			"response_format": "b64_json",
+		}).
+		SetResult(&result).
+		Post(cfg.OpenAIBaseURL + config.ImageGenerationsPath)
+
+	if err != nil {
+		return "", fmt.Errorf("request failed: %w", err)
+	}
+
+	if resp.StatusCode() != 200 {
+		var errResp struct {
+			Error struct {
+				Message string `json:"message"`
+			} `json:"error"`
+		}
+		if json.Unmarshal(resp.Body(), &errResp) == nil && errResp.Error.Message != "" {
+			return "", fmt.Errorf("%s", errResp.Error.Message)
+		}
+		return "", fmt.Errorf("API error (status %d): %s", resp.StatusCode(), resp.Status())
+	}
+
+	if len(result.Data) == 0 {
+		return "", errors.New("empty image result")
+	}
+
+	return result.Data[0].B64JSON, nil
+}
+
+func saveImage(b64 string) (string, error) {
+	cfg := config.Cfg
+
+	imgBytes, err := base64.StdEncoding.DecodeString(b64)
+	if err != nil {
+		return "", fmt.Errorf("base64 decode failed: %w", err)
+	}
+
+	filename := filepath.Join(cfg.ImageOutputDir, fmt.Sprintf("%d.png", time.Now().UnixNano()))
+	if err := os.WriteFile(filename, imgBytes, 0644); err != nil {
+		return "", fmt.Errorf("write file failed: %w", err)
+	}
+
+	return filename, nil
+}
+
+func uploadImage(filePath string) (string, error) {
+	cfg := config.Cfg
+	if cfg.UploadURL == "" {
+		return "", errors.New("UPLOAD_URL not set")
+	}
+
+	filename := filepath.Base(filePath)
+	var result UploadResp
+
+	resp, err := uploadClient.R().
+		SetHeader("X-API-Key", cfg.UploadAPIKey).
+		SetFile(filename, filePath).
+		SetResult(&result).
+		Post(cfg.UploadURL)
+
+	if err != nil {
+		return "", fmt.Errorf("upload request failed: %w", err)
+	}
+
+	if resp.StatusCode() != 200 {
+		return "", fmt.Errorf("upload failed (status %d): %s", resp.StatusCode(), resp.Status())
+	}
+
+	if result.Code != 0 {
+		return "", fmt.Errorf("upload error: %s", result.Msg)
+	}
+
+	return result.Data.Path, nil
+}