package routes

import (
	"log"
	"net/http"
	"path"
	"path/filepath"
	"strings"

	"github.com/dimfeld/httptreemux/v5"
	"github.com/fsnotify/fsnotify"

	"alin.ovh/elgit/config"
)

// Checks for gitprotocol-http(5) specific smells; if found, passes
// the request on to the git http service, else render the web frontend.
func (d *deps) Multiplex(w http.ResponseWriter, r *http.Request, params map[string]string) {
	rest := params["rest"]
	switch params["name"] {
	case "info", "git-upload-pack":
		rest = path.Join(params["name"], params["rest"])
		params["name"] = params["category"]
		params["category"] = ""
	}

	if d.isNotAllowed(path.Join(params["category"], params["name"])) {
		d.Write404(w)

		return
	}

	if r.URL.RawQuery == "service=git-receive-pack" {
		w.WriteHeader(http.StatusBadRequest)
		_, err := w.Write([]byte("no pushing allowed!"))
		if err != nil {
			log.Println(err)
			d.Write500(w)

			return
		}

		return
	}

	if rest == "info/refs" &&
		r.URL.RawQuery == "service=git-upload-pack" &&
		r.Method == "GET" {
		d.InfoRefs(w, r, params)
	} else if rest == "git-upload-pack" && r.Method == "POST" {
		d.UploadPack(w, r, params)
	} else if r.Method == "GET" {
		if fixed, found := strings.CutSuffix(r.URL.Path, "/"); found {
			http.Redirect(w, r, fixed, http.StatusPermanentRedirect)
		} else {
			d.RepoIndex(w, r, params)
		}
	}
}

func Handlers(c *config.Config) *httptreemux.TreeMux {
	mux := httptreemux.New()

	plist := filepath.Join(c.Repo.Root, "projects.list")
	projects, err := ReadProjectsList(plist)
	if err != nil {
		log.Fatal(err)
	}

	d := deps{
		c,
		projects,
	}

	watcher, err := fsnotify.NewWatcher()
	if err != nil {
		log.Fatal(err)
	}

	err = watcher.Add(plist)
	if err != nil {
		log.Fatal(err)
	}

	go func() {
		for {
			select {
			case event, ok := <-watcher.Events:
				if !ok {
					continue
				}
				if event.Op.Has(fsnotify.Write) {
					d.projects, err = ReadProjectsList(plist)
					if err != nil {
						log.Println(err)
					}
				}
			case err, ok := <-watcher.Errors:
				if !ok {
					continue
				}
				log.Println("error:", err)
			}
		}
	}()

	mux.NotFoundHandler = func(w http.ResponseWriter, r *http.Request) {
		d.Write404(w)
	}

	mux.RedirectTrailingSlash = false

	mux.GET("/", d.Index)
	mux.GET("/static/:file", d.ServeStatic)

	mux.GET("/:name/tree/:ref/*rest", d.RepoTree)
	mux.GET("/:name/blob/:ref/*rest", d.FileContent)
	mux.GET("/:name/tree/:ref/", d.RepoTree)
	mux.GET("/:name/blob/:ref/", d.FileContent)
	mux.GET("/:name/log/:ref", d.Log)
	mux.GET("/:name/archive/:file", d.Archive)
	mux.GET("/:name/commit/:ref", d.Diff)
	mux.GET("/:name/commit/:ref/*file", d.FileDiff)
	mux.GET("/:name/refs/", d.Refs)
	mux.GET("/:name", d.Multiplex)
	mux.POST("/:name", d.Multiplex)
	mux.GET("/:name/", d.Multiplex)
	mux.POST("/:name/", d.Multiplex)
	mux.GET("/:name/*rest", d.Multiplex)
	mux.POST("/:name/*rest", d.Multiplex)

	mux.GET("/:category/:name/tree/:ref/*rest", d.RepoTree)
	mux.GET("/:category/:name/blob/:ref/*rest", d.FileContent)
	mux.GET("/:category/:name/tree/:ref/", d.RepoTree)
	mux.GET("/:category/:name/blob/:ref/", d.FileContent)
	mux.GET("/:category/:name/log/:ref", d.Log)
	mux.GET("/:category/:name/archive/:file", d.Archive)
	mux.GET("/:category/:name/commit/:ref", d.Diff)
	mux.GET("/:category/:name/commit/:ref/*file", d.FileDiff)
	mux.GET("/:category/:name/refs/", d.Refs)
	mux.GET("/:category/:name", d.Multiplex)
	mux.POST("/:category/:name", d.Multiplex)
	mux.GET("/:category/:name/", d.Multiplex)
	mux.POST("/:category/:name/", d.Multiplex)
	mux.GET("/:category/:name/*rest", d.Multiplex)
	mux.POST("/:category/:name/*rest", d.Multiplex)

	return mux
}