package router

import (
	"fmt"
	"net/http"
	"strconv"
	"time"

	elastic "gopkg.in/olivere/elastic.v5"

	"github.com/NyaaPantsu/nyaa/config"
	"github.com/NyaaPantsu/nyaa/db"
	"github.com/NyaaPantsu/nyaa/model"
	"github.com/NyaaPantsu/nyaa/service/captcha"
	"github.com/NyaaPantsu/nyaa/service/notifier"
	"github.com/NyaaPantsu/nyaa/service/torrent"
	"github.com/NyaaPantsu/nyaa/service/upload"
	"github.com/NyaaPantsu/nyaa/service/user"
	"github.com/NyaaPantsu/nyaa/service/user/permission"
	"github.com/NyaaPantsu/nyaa/util/log"
	msg "github.com/NyaaPantsu/nyaa/util/messages"
	"github.com/NyaaPantsu/nyaa/util/publicSettings"
)

// UploadHandler : Main Controller for uploading a torrent
func UploadHandler(w http.ResponseWriter, r *http.Request) {
	defer r.Body.Close()
	user := getUser(r)
	if !uploadService.IsUploadEnabled(*user) {
		http.Error(w, "Error uploads are disabled", http.StatusBadRequest)
		return
	}

	if r.Method == "POST" {
		UploadPostHandler(w, r)
	}

	UploadGetHandler(w, r)
}

// UploadPostHandler : Controller for uploading a torrent, after POST request, redirect or makes error in messages
func UploadPostHandler(w http.ResponseWriter, r *http.Request) {
	var uploadForm uploadForm
	defer r.Body.Close()
	user := getUser(r)
	messages := msg.GetMessages(r) // new util for errors and infos

	if userPermission.NeedsCaptcha(user) {
		userCaptcha := captcha.Extract(r)
		if !captcha.Authenticate(userCaptcha) {
			messages.AddError("errors", captcha.ErrInvalidCaptcha.Error())
		}
	}

	// validation is done in ExtractInfo()
	err := uploadForm.ExtractInfo(r)
	if err != nil {
		messages.AddError("errors", err.Error())
	}
	status := model.TorrentStatusNormal
	if uploadForm.Remake { // overrides trusted
		status = model.TorrentStatusRemake
	} else if user.IsTrusted() {
		status = model.TorrentStatusTrusted
	}

	torrentIndb := model.Torrent{}
	db.ORM.Unscoped().Model(&model.Torrent{}).Where("torrent_hash = ?", uploadForm.Infohash).First(&torrentIndb)
	if torrentIndb.ID > 0 {
		if userPermission.CurrentUserIdentical(user, torrentIndb.UploaderID) && torrentIndb.IsDeleted() && !torrentIndb.IsBlocked() { // if torrent is not locked and is deleted and the user is the actual owner
			torrentService.DefinitelyDeleteTorrent(strconv.Itoa(int(torrentIndb.ID)))
		} else {
			messages.AddError("errors", "Torrent already in database !")
		}
	}

	if !messages.HasErrors() {
		// add to db and redirect
		torrent := model.Torrent{
			Name:        uploadForm.Name,
			Category:    uploadForm.CategoryID,
			SubCategory: uploadForm.SubCategoryID,
			Status:      status,
			Hidden:      uploadForm.Hidden,
			Hash:        uploadForm.Infohash,
			Date:        time.Now(),
			Filesize:    uploadForm.Filesize,
			Description: uploadForm.Description,
			WebsiteLink: uploadForm.WebsiteLink,
			UploaderID:  user.ID}
		torrent.ParseTrackers(uploadForm.Trackers)
		db.ORM.Create(&torrent)

		client, err := elastic.NewClient()
		if err == nil {
			err = torrent.AddToESIndex(client)
			if err == nil {
				log.Infof("Successfully added torrent to ES index.")
			} else {
				log.Errorf("Unable to add torrent to ES index: %s", err)
			}
		} else {
			log.Errorf("Unable to create elasticsearch client: %s", err)
		}

		url, err := Router.Get("view_torrent").URL("id", strconv.FormatUint(uint64(torrent.ID), 10))

		if user.ID > 0 && config.DefaultUserSettings["new_torrent"] { // If we are a member and notifications for new torrents are enabled
			userService.GetFollowers(user) // We populate the liked field for users
			if len(user.Followers) > 0 {   // If we are followed by at least someone
				for _, follower := range user.Followers {
					follower.ParseSettings() // We need to call it before checking settings
					if follower.Settings.Get("new_torrent") {
						T, _, _ := publicSettings.TfuncAndLanguageWithFallback(follower.Language, follower.Language) // We need to send the notification to every user in their language

						notifierService.NotifyUser(&follower, torrent.Identifier(), fmt.Sprintf(T("new_torrent_uploaded"), torrent.Name, user.Username), url.String(), follower.Settings.Get("new_torrent_email"))
					}
				}
			}
		}

		// add filelist to files db, if we have one
		if len(uploadForm.FileList) > 0 {
			for _, uploadedFile := range uploadForm.FileList {
				file := model.File{TorrentID: torrent.ID, Filesize: uploadedFile.Filesize}
				err := file.SetPath(uploadedFile.Path)
				if err != nil {
					messages.AddError("errors", err.Error())
				}
				db.ORM.Create(&file)
			}
		}

		if err != nil {
			http.Error(w, err.Error(), http.StatusInternalServerError)
			return
		}
		http.Redirect(w, r, url.String()+"?success", 302)
	}
}

// UploadGetHandler : Controller for uploading a torrent, after GET request or Failed Post request
func UploadGetHandler(w http.ResponseWriter, r *http.Request) {
	defer r.Body.Close()
	messages := msg.GetMessages(r) // new util for errors and infos

	var uploadForm uploadForm
	_ = uploadForm.ExtractInfo(r)
	user := getUser(r)
	if userPermission.NeedsCaptcha(user) {
		uploadForm.CaptchaID = captcha.GetID()
	} else {
		uploadForm.CaptchaID = ""
	}

	utv := formTemplateVariables{
		commonTemplateVariables: newCommonVariables(r),
		Form:       uploadForm,
		FormErrors: messages.GetAllErrors(),
	}
	err := uploadTemplate.ExecuteTemplate(w, "index.html", utv)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
}