GitHub 仓库链接解析 (#229)

* 群内接收到 GitHub 仓库链接时自动解析并发送仓库信息的图片。

plugin/ghrepo/ghrepo.go

@@ -0,0 +1,68 @@
+// Package ghrepo GitHub 仓库链接解析
+package ghrepo
+
+import (
+	b64 "encoding/base64"
+	"strings"
+
+	"github.com/FloatTech/floatbox/binary"
+	"github.com/FloatTech/floatbox/web"
+	ctrl "github.com/FloatTech/zbpctrl"
+	"github.com/FloatTech/zbputils/control"
+	"github.com/sirupsen/logrus"
+	"github.com/tidwall/gjson"
+	zero "github.com/wdvxdr1123/ZeroBot"
+	"github.com/wdvxdr1123/ZeroBot/message"
+)
+
+const (
+	repoAPI  = "https://api.github.com/repos/"
+	imageAPI = "https://opengraph.githubassets.com/1a/"
+)
+
+func init() {
+	en := control.Register("ghrepo", &ctrl.Options[*zero.Ctx]{
+		DisableOnDefault: false,
+		Brief:            "GitHub 仓库链接解析",
+		Help:             "群内接收到 GitHub 仓库链接时自动解析并发送仓库信息的图片。",
+	})
+	en.OnPrefix("https://github.com/").SetBlock(true).
+		Handle(func(ctx *zero.Ctx) {
+			repoInfo := ctx.Event.Message.ExtractPlainText()[19:]
+			// 去除域名后内容过短，忽略消息
+			if len(repoInfo) <= 2 {
+				return
+			}
+			// 删除末尾的 /
+			if repoInfo[len(repoInfo)-1] == '/' {
+				repoInfo = repoInfo[:len(repoInfo)-1]
+			}
+			// 检查是否同时含有用户名和仓库名
+			repoInfoSlice := strings.Split(repoInfo, "/")
+			if len(repoInfoSlice) != 2 {
+				return
+			}
+			// 检查仓库是否存在
+			// TODO: 此处 API 调用存在限制，加 token 之后会获得更多的调用次数
+			data, err := web.GetData(repoAPI + repoInfo)
+			if err != nil {
+				logrus.Errorln("[github]", "Fail to check repo status", err)
+				return
+			}
+			repoStatusMessage := gjson.Get(binary.BytesToString(data), "message").String()
+			// 仓库不存在，忽略
+			if repoStatusMessage == "Not Found" {
+				return
+			}
+			// 下载仓库图片
+			imageData, err := web.GetData(imageAPI + repoInfo)
+			if err != nil {
+				logrus.Errorln("[github]", "Fail to download repo image", err)
+				return
+			}
+			// 发送仓库图片
+			repoText := "https://github.com/" + repoInfo
+			imageB64 := "base64://" + b64.StdEncoding.EncodeToString(imageData)
+			ctx.SendChain(message.Reply(ctx.Event.MessageID), message.Text(repoText), message.Image(imageB64))
+		})
+}