From d8bf2d3227d25081561c0d88600e8e1f9c424db3 Mon Sep 17 00:00:00 2001
From: erinn <erinn@openprivacy.ca>
Date: Tue, 14 Dec 2021 13:21:45 -0800
Subject: [PATCH] image previews wip

---
 .../filesharing/filesharing_functionality.go  | 36 +++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/functionality/filesharing/filesharing_functionality.go b/functionality/filesharing/filesharing_functionality.go
index 0dae38a..1cd6005 100644
--- a/functionality/filesharing/filesharing_functionality.go
+++ b/functionality/filesharing/filesharing_functionality.go
@@ -8,8 +8,10 @@ import (
 	"fmt"
 	"io"
 	"math"
+	"os"
 	path "path/filepath"
 	"strconv"
+	"strings"
 	"time"
 
 	"cwtch.im/cwtch/model"
@@ -31,6 +33,13 @@ func FunctionalityGate(experimentMap map[string]bool) (*Functionality, error) {
 	return nil, errors.New("filesharing is not enabled")
 }
 
+func PreviewFunctionalityGate(experimentMap map[string]bool) (*Functionality, error) {
+	if experimentMap["filesharing"] == true && experimentMap["filesharing-images"] == true {
+		return new(Functionality), nil
+	}
+	return nil, errors.New("image previews are not enabled")
+}
+
 // OverlayMessage presents the canonical format of the File Sharing functionality Overlay Message
 // This is the format that the UI will parse to display the message
 type OverlayMessage struct {
@@ -40,6 +49,10 @@ type OverlayMessage struct {
 	Size  uint64 `json:"s"`
 }
 
+func (om *OverlayMessage) FileKey() string {
+	return fmt.Sprintf("%s.%s", om.Hash, om.Nonce)
+}
+
 // 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, handle string, downloadFilePath string, manifestFilePath string, key string) {
@@ -101,3 +114,26 @@ func (f *Functionality) ShareFile(filepath string, profile peer.CwtchPeer, handl
 
 	return nil
 }
+
+func GenerateDownloadPath(basePath, fileName string) (filePath, manifestPath string) {
+	filePath = fmt.Sprintf("%s%s", basePath, fileName)
+	manifestPath = fmt.Sprintf("%s.manifest", filePath)
+
+	parts := strings.Split(fileName, ".")
+	fileNameBase := parts[0]
+	fileNameExt := ""
+	if len(parts) > 1 {
+		fileNameBase = strings.Join(parts[0:len(parts)-1], ".")
+		fileNameExt = fmt.Sprintf(".%s", parts[len(parts)-1])
+	}
+
+	for i := 2; ; i++ {
+		if _, err := os.Open(filePath); os.IsNotExist(err) {
+			if _, err := os.Open(manifestPath); os.IsNotExist(err) {
+				return
+			}
+		}
+		filePath = fmt.Sprintf("%s%s (%d)%s", basePath, fileNameBase, i, fileNameExt)
+		manifestPath = fmt.Sprintf("%s.manifest", filePath)
+	}
+}