package controllers

import (
	"net/http"
	"strings"

	"congo.gg/pkg/application"
	"github.com/sosedoff/gitkit"
)

// GitController serves the congo repo over read-only git HTTP protocol.
type GitController struct {
	application.BaseController
	server *gitkit.Server
}

// Git returns the controller name and instance.
func Git() (string, *GitController) {
	return "git", &GitController{}
}

// Setup registers the git smart HTTP routes.
func (c *GitController) Setup(app *application.App) {
	c.BaseController.Setup(app)

	c.server = gitkit.New(gitkit.Config{
		Dir:        "/opt",
		AutoCreate: false,
	})

	http.HandleFunc("GET /git/congo.git/", c.handle)
	http.HandleFunc("POST /git/congo.git/", c.handle)
	http.HandleFunc("GET /git/congo.git/info/refs", c.handle)
	http.HandleFunc("POST /git/congo.git/git-upload-pack", c.handle)
}

// handle proxies to gitkit, blocking push operations.
func (c *GitController) handle(w http.ResponseWriter, r *http.Request) {
	if r.URL.Query().Get("service") == "git-receive-pack" {
		http.Error(w, "Push not allowed", http.StatusForbidden)
		return
	}
	if strings.HasSuffix(r.URL.Path, "git-receive-pack") {
		http.Error(w, "Push not allowed", http.StatusForbidden)
		return
	}

	// gitkit expects paths like /congo.git/...
	r.URL.Path = strings.TrimPrefix(r.URL.Path, "/git")

	c.server.ServeHTTP(w, r)
}

// Handle returns a request-scoped controller instance.
func (c GitController) Handle(r *http.Request) application.Controller {
	c.Request = r
	return &c
}