message previews - safety checks

functionality/filesharing/filesharing_functionality.go

@@ -10,6 +10,7 @@ import (
 	"math"
 	"os"
 	path "path/filepath"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -54,6 +55,12 @@ func (om *OverlayMessage) FileKey() string {
 	return fmt.Sprintf("%s.%s", om.Hash, om.Nonce)
 }
 
+// checks file size and file name. *DOES NOT* check user settings or contact state
+func (om *OverlayMessage) ShouldAutoDL() bool {
+	lname := strings.ToLower(om.Name)
+	return om.Size <= 20971520 && (strings.HasSuffix(lname, "jpg") || strings.HasSuffix(lname, "jpeg") || strings.HasSuffix(lname, "png") || strings.HasSuffix(lname, "gif") || strings.HasSuffix(lname, "webp") || strings.HasSuffix(lname, "bmp"))
+}
+
 // DownloadFile given a profile, a conversation handle and a file sharing key, start off a download process
 // to downloadFilePath
 func (f *Functionality) DownloadFile(profile peer.CwtchPeer, conversationID int, downloadFilePath string, manifestFilePath string, key string) {
@@ -118,9 +125,26 @@ func (f *Functionality) ShareFile(filepath string, profile peer.CwtchPeer, conve
 }
 
 func GenerateDownloadPath(basePath, fileName string) (filePath, manifestPath string) {
+	// avoid all kina funky shit
+	re := regexp.MustCompile(`[^A-Za-z0-9._-]`)
+	filePath = re.ReplaceAllString(filePath, "")
+	// avoid hidden files on linux
+	for strings.HasPrefix(filePath, ".") {
+		filePath = strings.TrimPrefix(filePath, ".")
+	}
+	// avoid empties
+	if strings.TrimSpace(filePath) == "" {
+		filePath = "untitled"
+	}
+	// if you like it, put a / on it
+	if !strings.HasSuffix(basePath, string(os.PathSeparator)) {
+		basePath = fmt.Sprintf("%s%s", basePath, string(os.PathSeparator))
+	}
 	filePath = fmt.Sprintf("%s%s", basePath, fileName)
 	manifestPath = fmt.Sprintf("%s.manifest", filePath)
 
+	// if file is named "file", iterate "file", "file (2)", "file (3)", ... until DNE
+	// if file is named "file.ext", iterate "file.ext", "file (2).ext", "file (3).ext", ... until DNE
 	parts := strings.Split(fileName, ".")
 	fileNameBase := parts[0]
 	fileNameExt := ""