package main

import (
	"crypto/rand"
	"fmt"
	"net/http"
	"time"

	"humungus.tedunangst.com/r/webs/junk"
	"humungus.tedunangst.com/r/webs/login"
)

type NotResponseWriter struct {
	body   []byte
	header http.Header
}

func (w NotResponseWriter) Header() http.Header {
	return w.header
}

func (w NotResponseWriter) Write(b []byte) (int, error) {
	w.body = b
	return 0, nil
}

func (w NotResponseWriter) WriteHeader(statusCode int) {}

func snowflake() uint64 {
	ts := time.Now()
	return uint64(uint64(ts.UnixNano()/int64(time.Millisecond))<<16 | uint64(time.Now().Nanosecond()&0xffff))
}

func badjunk(rw http.ResponseWriter, j junk.Junk, path string) {
	elog.Printf("%s: bad junk: %s", path, j.ToString())
	http.Error(rw, fmt.Sprintf("%s: bad junk", path), http.StatusBadRequest)
}

func goodjunk(rw http.ResponseWriter, j junk.Junk) {
	rw.WriteHeader(http.StatusOK)
	rw.Header().Set("Content-Type", "application/json; charset=utf-8")
	rw.Write(j.ToBytes())
}

func showoauthlogin(rw http.ResponseWriter, r *http.Request) {
	templinfo := make(map[string]interface{})
	templinfo = getInfo(r)
	if err := readviews.Execute(rw, "oauthlogin.html", templinfo); err != nil {
		elog.Println(err)
	}
}

// https://docs.joinmastodon.org/methods/apps/#create
func apiapps(rw http.ResponseWriter, r *http.Request) {
	if err := r.ParseForm(); err != nil {
		http.Error(rw, "invalid input", http.StatusUnprocessableEntity)
		elog.Println(err)
		return
	}
	clientName := r.Form.Get("client_name")
	redirectUri := r.Form.Get("redirect_uris")
	scopes := r.Form.Get("scopes")
	website := r.Form.Get("website")
	clientID := tokengen()
	clientSecret := tokengen()
	vapidKey := tokengen()

	_, err := stmtSaveMastoApp.Exec(clientName, redirectUri, scopes, clientID, clientSecret, vapidKey)
	if err != nil {
		elog.Printf("error saving masto app: %v", err)
		http.Error(rw, "error saving masto app", http.StatusUnprocessableEntity)
		return
	}

	j := junk.New()
	j["id"] = fmt.Sprintf("%d", snowflake())
	j["website"] = website
	j["name"] = clientName
	j["redirect_uri"] = redirectUri
	j["client_id"] = clientID
	j["client_secret"] = clientSecret
	j["vapid_key"] = vapidKey

	fmt.Println(j.ToString())
	goodjunk(rw, j)
}

func tokengen() string {
	b := make([]byte, 32)
	rand.Read(b)
	return fmt.Sprintf("%x", b)
}

// https://docs.joinmastodon.org/methods/oauth/#authorize
func oauthorize(rw http.ResponseWriter, r *http.Request) {
	nrw := NotResponseWriter{}
	login.LoginFunc(nrw, r)
	dlog.Println("got code!", string(nrw.body))
	rw.WriteHeader(http.StatusOK)
	return
}

// https://docs.joinmastodon.org/methods/instance/#v2
func instance(rw http.ResponseWriter, r *http.Request) {
	j := junk.New()

	var servername string
	if err := getconfig("servername", &servername); err != nil {
		http.Error(rw, "getting servername", http.StatusInternalServerError)
		return
	}

	j["uri"] = servername
	j["title"] = "honk"
	j["description"] = "federated honk conveyance"
	j["version"] = "develop"

	thumbnail := junk.New()
	thumbnail["url"] = fmt.Sprintf("https://%s/icon.png", servername)
	j["thumbnail"] = thumbnail
	j["languages"] = []string{"en"}

	config := junk.New()

	a := junk.New()
	a["max_featured_tags"] = 10
	config["accounts"] = a

	s := junk.New()
	s["max_characters"] = 5000
	s["max_media_attachments"] = 1
	s["characters_reserved_per_url"] = 23
	config["statuses"] = s

	m := junk.New()
	m["supported_mime_types"] = []string{
		"image/jpeg",
		"image/png",
		"image/gif",
		"image/heic",
		"image/heif",
		"image/webp",
		"image/avif",
		"video/webm",
		"video/mp4",
		"video/quicktime",
		"video/ogg",
		"audio/wave",
		"audio/wav",
		"audio/x-wav",
		"audio/x-pn-wave",
		"audio/vnd.wave",
		"audio/ogg",
		"audio/vorbis",
		"audio/mpeg",
		"audio/mp3",
		"audio/webm",
		"audio/flac",
		"audio/aac",
		"audio/m4a",
		"audio/x-m4a",
		"audio/mp4",
		"audio/3gpp",
		"video/x-ms-asf",
	}

	m["image_size_limit"] = 10485760
	m["image_matrix_limit"] = 16777216
	m["video_size_limit"] = 41943040
	m["video_frame_rate_limit"] = 60
	m["video_matrix_limit"] = 2304000
	j["media_attachments"] = m

	rw.WriteHeader(http.StatusOK)
	rw.Write(j.ToBytes())

	return
}