package common

import (
	"mime/multipart"
	"net/http"

	fileutil "management/internal/pkg/file"
	"management/internal/pkg/tpl"
)

type UploadHandler interface {
	Img(w http.ResponseWriter, r *http.Request)
	File(w http.ResponseWriter, r *http.Request)
	MutilFiles(w http.ResponseWriter, r *http.Request)
}

type uploadHandler struct {
	render tpl.Renderer
}

var _ UploadHandler = (*uploadHandler)(nil)

func NewUploadHandler(render tpl.Renderer) *uploadHandler {
	return &uploadHandler{
		render: render,
	}
}

const maxImageSize = 100 << 20 // 100 MB

func (h *uploadHandler) Img(w http.ResponseWriter, r *http.Request) {
	defer r.Body.Close()

	_, fh, err := r.FormFile("files")
	if err != nil {
		h.render.JSONERR(w, err.Error())
		return
	}

	path, err := fileutil.UploadFile(fh, fileutil.IMG)
	if err != nil {
		h.render.JSONERR(w, err.Error())
		return
	}

	h.render.JSON(w, tpl.Response{Success: true, Message: "ok", Data: path})
}

func (h *uploadHandler) File(w http.ResponseWriter, r *http.Request) {
	defer r.Body.Close()

	_, fh, err := r.FormFile("files")
	if err != nil {
		h.render.JSONERR(w, err.Error())
		return
	}

	path, err := fileutil.UploadFile(fh, fileutil.ALL)
	if err != nil {
		h.render.JSONERR(w, err.Error())
		return
	}

	h.render.JSON(w, tpl.Response{Success: true, Message: "ok", Data: path})
}

type UploadFileRes struct {
	Name string `json:"name"`
	Path string `json:"path"`
}

func (h *uploadHandler) MutilFiles(w http.ResponseWriter, r *http.Request) {
	defer r.Body.Close()

	err := r.ParseMultipartForm(int64(maxImageSize))
	if err != nil {
		return
	}
	files := r.MultipartForm.File["files"]

	var res []UploadFileRes
	c := make(chan UploadFileRes, 2)
	defer close(c)

	for i, file := range files {
		go func(item *multipart.FileHeader, key int) {
			ufr := UploadFileRes{Name: item.Filename}

			filePath, err := fileutil.UploadFile(item, fileutil.ALL)
			if err != nil {
				h.render.JSONERR(w, err.Error())
				return
			}

			ufr.Path = filePath
			c <- ufr
		}(file, i)
	}

	for {
		v, ok := <-c
		if ok {
			res = append(res, v)
		}
		if len(files) == len(res) {
			break
		}
	}

	h.render.JSON(w, tpl.Response{Success: true, Message: "ok", Data: res})
}