package controller

import (
	"encoding/base64"
	"fmt"
	"html/template"
	"io"
	"log"
	"net/http"
	"net/url"
	"time"

	"drop.janw.name/storage"
	qrcode "github.com/skip2/go-qrcode"
)

const MAX_FILESIZE = (1 << 19) * 100

func (app App) FilePost(res http.ResponseWriter, req *http.Request) {
	if !app.requireAuth(res, req) {
		return
	}

	if err := req.ParseMultipartForm(MAX_FILESIZE); err != nil {
		panic(err)
	}

	formFile, formFileHeader, err := req.FormFile("file")
	if err != nil {
		panic(err)
	}

	protected := req.FormValue("protect") == "on"

	fileData, err := io.ReadAll(formFile)
	if err != nil {
		panic(err)
	}

	file := storage.File{
		Protected:      protected,
		Filename:       formFileHeader.Filename,
		Data:           fileData,
		AvailableUntil: time.Now().Add(time.Hour * 24),
	}

	key, err := app.storage.Put(file)
	if err != nil {
		panic(err)
	}

	log.Println("received new file:", key)

	downloadURL := fmt.Sprintf("%s/%s", app.config.Http.BaseAddress, key)
	qrcodePng, err := qrcode.Encode(downloadURL, qrcode.Medium, 256)

	if err != nil {
		panic(err)
	}

	qrcodeDataUrl := fmt.Sprintf(
		"data:image/png;base64,%s",
		url.QueryEscape(base64.StdEncoding.WithPadding('=').EncodeToString(qrcodePng)),
	)

	app.tmpl.ExecuteTemplate(res, "uploaded", struct {
		DownloadURL string
		QRCode      template.URL
	}{
		DownloadURL: downloadURL,
		QRCode:      template.URL(qrcodeDataUrl),
	})
}

func (app App) FileGet(res http.ResponseWriter, req *http.Request) {
	fileId := req.PathValue("file")

	file, _ := app.storage.Get(fileId)

	if file == nil || !file.IsAvailable() {
		if !app.requireAuth(res, req) {
			return
		}

		res.WriteHeader(http.StatusNotFound)
		app.tmpl.ExecuteTemplate(res, "404", nil)
		return
	}

	if file.Protected && !app.requireAuth(res, req) {
		return
	}

	res.Header().Add("Content-Type", "application/octet-stream")
	res.Header().Add("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s\"", file.Filename))

	if _, err := res.Write(file.Data); err != nil {
		panic(err)
	} else {
		log.Println("served file:", fileId, file.Filename)
	}
}