package httpRequest

import (
	"io"
	"net/http"
	"strings"

	"go-socket/packages/globals"
)

type postType uint8

const (
	postNormal postType = iota
	postFile
	postAvatar
	postProfileBg
)

func postValidCheckWithResponseOnFail(response *http.ResponseWriter, request *http.Request, pt postType) bool {
	if request.Method != http.MethodPost {
		http.Error(*response, "POST only", http.StatusMethodNotAllowed)
		return false
	}

	var maxSize int64
	switch pt {
	case postFile:
		maxSize = int64(globals.MaxPostWithFileBytes)
	case postAvatar:
		maxSize = int64(globals.MaxPostWithAvatar)
	case postProfileBg:
		maxSize = int64(globals.MaxPostWithProfileBg)
	default:
		maxSize = int64(globals.MaxPostBytes)
	}

	if request.ContentLength > maxSize {
		http.Error(*response, "Request too large", http.StatusRequestEntityTooLarge)
		return false
	}

	return true
}

func isImage(r io.Reader) (bool, string, error) {
	buf := make([]byte, 512)
	n, err := io.ReadFull(r, buf)
	if err != nil && err != io.EOF && err != io.ErrUnexpectedEOF {
		return false, "", err
	}

	contentType := http.DetectContentType(buf[:n])
	isImage := strings.HasPrefix(contentType, "image/") && contentType != "image/svg+xml"

	if seeker, ok := r.(io.Seeker); ok {
		if _, err := seeker.Seek(0, io.SeekStart); err != nil {
			return isImage, contentType, err
		}
	}

	return isImage, contentType, nil
}