Refactor web route handler (#33488)

routers/web/repo/watch.go

@@ -0,0 +1,31 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package repo
+
+import (
+	"net/http"
+
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/modules/templates"
+	"code.gitea.io/gitea/services/context"
+)
+
+const tplWatchUnwatch templates.TplName = "repo/watch_unwatch"
+
+func ActionWatch(ctx *context.Context) {
+	err := repo_model.WatchRepo(ctx, ctx.Doer, ctx.Repo.Repository, ctx.PathParam("action") == "watch")
+	if err != nil {
+		handleActionError(ctx, err)
+		return
+	}
+
+	ctx.Data["IsWatchingRepo"] = repo_model.IsWatching(ctx, ctx.Doer.ID, ctx.Repo.Repository.ID)
+	ctx.Data["Repository"], err = repo_model.GetRepositoryByName(ctx, ctx.Repo.Repository.OwnerID, ctx.Repo.Repository.Name)
+	if err != nil {
+		ctx.ServerError("GetRepositoryByName", err)
+		return
+	}
+	ctx.RespHeader().Add("hx-trigger", "refreshUserCards") // see the `hx-trigger="refreshUserCards ..."` comments in tmpl
+	ctx.HTML(http.StatusOK, tplWatchUnwatch)
+}