package server

import (
	"fmt"
	"net/http"
	"strings"

	"gitcat/internal/gitx"
	"gitcat/internal/store"
)

var reservedRepoNames = map[string]bool{
	"admin": true, "login": true, "logout": true, "install": true, "new": true,
	"settings": true, "static": true, "media": true, "favicon.ico": true, "api": true,
	"avatars": true, "assets": true, "help": true, "about": true,
}

func (s *Server) handleHome(w http.ResponseWriter, r *http.Request) {
	q := strings.TrimSpace(r.URL.Query().Get("q"))
	repos, err := s.st.ListRepos(q)
	if err != nil {
		s.renderError(w, r, http.StatusInternalServerError, "读取项目列表失败")
		return
	}
	pushes, _ := s.st.RecentPushes(8)
	users, repoCount, pushCount, _ := s.st.Counts()

	p := s.page(r, "项目")
	p.Active = "home"
	p.Data["Repos"] = repos
	p.Data["Query"] = q
	p.Data["RecentPushes"] = pushes
	p.Data["PushActors"] = s.pushActors(pushes)
	p.Data["StatRepos"] = repoCount
	p.Data["StatUsers"] = users
	p.Data["StatPushes"] = pushCount
	p.Data["HasRepos"] = len(repos) > 0
	p.Data["Announcement"] = s.st.GetSetting("announcement")
	s.render(w, r, "home", p)
}

func (s *Server) handleNewProjectPage(w http.ResponseWriter, r *http.Request) {
	u := s.requireLogin(w, r)
	if u == nil {
		return
	}
	if !s.st.Installed() {
		http.Redirect(w, r, "/install", http.StatusFound)
		return
	}
	p := s.page(r, "新建项目")
	p.Active = "new"
	s.render(w, r, "new_project", p)
}

func (s *Server) handleNewProjectSubmit(w http.ResponseWriter, r *http.Request) {
	u := s.requireLogin(w, r)
	if u == nil {
		return
	}
	if !s.checkCSRF(r) {
		s.renderError(w, r, http.StatusForbidden, "表单已过期，请返回重试")
		return
	}
	name := strings.TrimSpace(r.FormValue("name"))
	desc := strings.TrimSpace(r.FormValue("description"))
	name = strings.TrimSuffix(name, ".git")

	fail := func(msg string) {
		p := s.page(r, "新建项目")
		p.Active = "new"
		p.Error = msg
		p.Data["Name"] = name
		p.Data["Description"] = desc
		w.WriteHeader(http.StatusBadRequest)
		s.render(w, r, "new_project", p)
	}

	switch {
	case name == "":
		fail("请填写项目名称")
		return
	case !gitx.ValidRepoName(name):
		fail("项目名称只能包含字母、数字、点、下划线、短横线，且需以字母或数字开头")
		return
	case reservedRepoNames[strings.ToLower(name)]:
		fail("该名称为系统保留名，请换一个")
		return
	case len(desc) > 300:
		fail("项目描述不能超过 300 个字符")
		return
	}
	if _, err := s.st.RepoByName(name); err == nil {
		fail("项目 " + name + " 已存在")
		return
	}

	repo, err := s.st.CreateRepo(name, desc, u.ID)
	if err != nil {
		fail(err.Error())
		return
	}
	if err := gitx.InitBare(s.repoPath(repo.Name), repo.DefaultBranch); err != nil {
		_ = s.st.DeleteRepo(repo.ID)
		fail("初始化 git 仓库失败：" + err.Error())
		return
	}
	setFlash(w, fmt.Sprintf("项目 %s 创建成功，现在可以把代码推上来了", repo.Name))
	http.Redirect(w, r, "/"+repo.Name, http.StatusFound)
}

// canManageRepo 判断当前用户能否管理该仓库（创建者或管理员）。
func canManageRepo(u *store.User, repo *store.Repo) bool {
	if u == nil {
		return false
	}
	if u.IsAdmin {
		return true
	}
	return repo.OwnerID != nil && *repo.OwnerID == u.ID
}