package main

import (
	"encoding/json"
	"fmt"
	"github.com/gorilla/mux"
	"io/ioutil"
	"log"
	"net/http"
	"net/url"
	"os"
	"regexp"
	"time"
	"willnorris.com/go/webmention"
)

func Serve() {

	hookHandler := func(w http.ResponseWriter, r *http.Request) {
		fmt.Println("Fetch feeds: ", time.Now().Format(time.RFC3339))
		for _, actor := range actors {
			fmt.Println(actor.feed)
			articles, err := allFeedItems(actor.feed)
			if err != nil {
				fmt.Println(actor.feed, err.Error())
				continue
			}
			// Post latest article
			if articles[0] != actor.lastItem {
				err = actor.PostArticle(articles[0])
				if err != nil {
					fmt.Println("Posting", articles[0], "failed")
				} else {
					actor.lastItem = articles[0]
					_ = actor.save()
				}
			}
		}
	}

	webfingerHandler := func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("content-type", "application/jrd+json; charset=utf-8")
		name := r.URL.Query().Get("resource") // should be something like acct:user@example.com
		urlBaseUrl, _ := url.Parse(baseURL)
		re := regexp.MustCompile(`^acct:(.*)@` + regexp.QuoteMeta(urlBaseUrl.Host) + `$`)
		name = re.ReplaceAllString(name, "$1")
		actor := actors[name]
		// error out if this actor does not exist
		if actor == nil {
			w.WriteHeader(http.StatusNotFound)
			return
		}
		responseMap := make(map[string]interface{})
		responseMap["subject"] = "acct:" + actor.Name + "@" + urlBaseUrl.Host
		// links is a json array with a single element
		var links [1]map[string]string
		link1 := make(map[string]string)
		link1["rel"] = "self"
		link1["type"] = ContentTypeAs2
		link1["href"] = actor.iri
		links[0] = link1
		responseMap["links"] = links
		response, _ := json.Marshal(responseMap)
		_, _ = w.Write(response)
	}

	inboxHandler := func(w http.ResponseWriter, r *http.Request) {
		b, err := ioutil.ReadAll(r.Body)
		if err != nil {
			panic(err)
		}
		activity := make(map[string]interface{})
		err = json.Unmarshal(b, &activity)
		if err != nil {
			w.WriteHeader(http.StatusInternalServerError)
			return
		}
		actor := actors[mux.Vars(r)["actor"]]
		if actor == nil {
			// actor doesn't exist
			w.WriteHeader(http.StatusNotFound)
			return
		}
		f, err := os.OpenFile(storage+slash+"actors"+slash+actor.Name+slash+"inbox", os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
		if err != nil {
			w.WriteHeader(http.StatusInternalServerError)
			return
		}
		defer func() { _ = f.Close() }()
		_, _ = f.Write(b)
		_, _ = f.WriteString("\n---\n")
		switch activity["type"] {
		case "Follow":
			actor.Accept(activity)
		case "Undo":
			{
				if object, ok := activity["object"].(map[string]interface{}); ok {
					if objectType, ok := object["type"].(string); ok && objectType == "Follow" {
						if iri, ok := object["actor"].(string); ok && iri == activity["actor"] {
							_ = actor.RemoveFollower(iri)
							fmt.Println(iri, "unfollowed")
						}
					}
				}
			}
		case "Create":
			{
				if object, ok := activity["object"].(map[string]interface{}); ok {
					inReplyTo, ok := object["inReplyTo"].(string)
					id, ok2 := object["id"].(string)
					if ok && ok2 && len(inReplyTo) > 0 && len(id) > 0 {
						webmentionClient := webmention.New(nil)
						endpoint, err := webmentionClient.DiscoverEndpoint(inReplyTo)
						if err != nil || len(endpoint) < 1 {
							return
						}
						_, err = webmentionClient.SendWebmention(endpoint, id, inReplyTo)
						if err != nil {
							log.Println("Sending webmention to " + inReplyTo + " failed")
						} else {
							log.Println("Sent webmention to " + inReplyTo)
						}
					}
				}
			}
		case "Delete":
			{
				if object, ok := activity["object"].(string); ok && len(object) > 0 && activity["actor"] == object {
					_ = actor.RemoveFollower(object)
					fmt.Println("Deleted", object)
				}
			}
		}
		// Return 201
		w.WriteHeader(http.StatusCreated)
	}

	// Add the handlers to a HTTP server
	gorilla := mux.NewRouter()
	gorilla.HandleFunc("/hook", hookHandler).Methods(http.MethodPost)
	gorilla.HandleFunc("/.well-known/webfinger", webfingerHandler)
	gorilla.PathPrefix("/{actor}/inbox").HandlerFunc(inboxHandler).Methods(http.MethodPost)
	http.Handle("/", gorilla)

	log.Fatal(http.ListenAndServe(":8081", nil))
}