package handlers

import (
	"errors"
	"fmt"
	"mime/multipart"
	"net/http"
	"strconv"
	"strings"

	"warpbox.dev/backend/libs/helpers"
	"warpbox.dev/backend/libs/jobs"
	"warpbox.dev/backend/libs/services"
)

func (a *App) Upload(w http.ResponseWriter, r *http.Request) {
	user, loggedIn := a.currentUser(r)
	isAdminUpload := loggedIn && user.Role == services.UserRoleAdmin
	if !isAdminUpload {
		r.Body = http.MaxBytesReader(w, r.Body, a.uploadService.MaxUploadSize()*8)
	}
	parseLimit := a.uploadService.MaxUploadSize() * 8
	if isAdminUpload {
		parseLimit = 32 << 20
	}
	if err := r.ParseMultipartForm(parseLimit); err != nil {
		helpers.WriteJSONError(w, http.StatusBadRequest, "upload form could not be read")
		return
	}

	files := uploadFiles(r)
	var ownerID string
	var collectionID string
	if loggedIn {
		ownerID = user.ID
		collectionID = r.FormValue("collection_id")
		if !a.authService.CollectionOwnedBy(collectionID, user.ID) {
			helpers.WriteJSONError(w, http.StatusForbidden, "collection not found")
			return
		}
	}
	result, err := a.uploadService.CreateBox(files, services.UploadOptions{
		MaxDays:           parseInt(r.FormValue("max_days")),
		MaxDownloads:      parseInt(r.FormValue("max_downloads")),
		Password:          r.FormValue("password"),
		ObfuscateMetadata: r.FormValue("obfuscate_metadata") == "on",
		OwnerID:           ownerID,
		CollectionID:      collectionID,
		SkipSizeLimit:     isAdminUpload,
	})
	if err != nil {
		a.logger.Warn("upload failed", "source", "user-upload", "severity", "warn", "code", 4001, "error", err.Error())
		helpers.WriteJSONError(w, http.StatusBadRequest, err.Error())
		return
	}
	jobs.GenerateThumbnailsForBoxAsync(a.uploadService, a.logger, result.BoxID)

	if wantsJSON(r) {
		helpers.WriteJSON(w, http.StatusCreated, result)
		return
	}

	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
	w.WriteHeader(http.StatusCreated)
	_, _ = fmt.Fprintln(w, result.BoxURL)
}

func parseInt(value string) int {
	if value == "" {
		return 0
	}
	parsed, err := strconv.Atoi(value)
	if err != nil {
		return 0
	}
	return parsed
}

func statusForDownloadError(err error) int {
	if errors.Is(err, http.ErrMissingFile) {
		return http.StatusNotFound
	}
	return http.StatusForbidden
}

func uploadFiles(r *http.Request) []*multipart.FileHeader {
	if r.MultipartForm == nil {
		return nil
	}
	files := make([]*multipart.FileHeader, 0)
	files = append(files, r.MultipartForm.File["file"]...)
	files = append(files, r.MultipartForm.File["sharex"]...)
	return files
}

func wantsJSON(r *http.Request) bool {
	return strings.Contains(strings.ToLower(r.Header.Get("Accept")), "application/json")
}