From 73ab6461baee168c4504162653dcf9060325b461 Mon Sep 17 00:00:00 2001
From: Your Name <you@example.com>
Date: Sun, 2 Sep 2018 19:10:41 +0000
Subject: [PATCH] Initial add of sorting

---
 enhanced-file-server.go | 42 +++++++++++++++++++++++++++++++++++++++--
 1 file changed, 40 insertions(+), 2 deletions(-)

diff --git a/enhanced-file-server.go b/enhanced-file-server.go
index 80096e9..0166d08 100644
--- a/enhanced-file-server.go
+++ b/enhanced-file-server.go
@@ -50,16 +50,54 @@ func mapDirOpenError(originalErr error, name string) error {
 }
 
 func dirList(w http.ResponseWriter, r *http.Request, f http.File) {
+	tableheader := ""
 	dirs, err := f.Readdir(-1)
 	if err != nil {
 		logf(r, "http: error reading directory: %v", err)
 		http.Error(w, "Error reading directory", http.StatusInternalServerError)
 		return
 	}
+	// Check for sort parameters
+	key, ok := r.URL.Query()["key"]
+	if !ok || (key[0] != "filename" && key[0] != "date" && key[0] != "size") {
+		key[0] = "filename"
+	}
+
+	order, ok := r.URL.Query()["key"]
+	if !ok || (order[0] != "asc" && order[0] != "desc") {
+		order[0] = "asc"
+	}
+	switch {
+	case (key[0] == "filename" && order[0] == "asc"):
+		sort.Slice(dirs, func(i, j int) bool { return dirs[i].Name() < dirs[j].Name() })
+		tableheader = "<th><a href='?key=filename&order=desc'>Filename</a></th><th><a href='?key=size'>Size</a></th><th><a href='?key=date'>Date</a></th>"
+	case (key[0] == "filename" && order[0] == "desc"):
+		sort.Slice(dirs, func(i, j int) bool { return dirs[i].Name() > dirs[j].Name() })
+		tableheader = "<th><a href='?key=filename&order=asc'>Filename</a></th><th><a href='?key=size'>Size</a></th><th><a href='?key=date'>Date</a></th>"
+
+	case (key[0] == "size" && order[0] == "asc"):
+		sort.Slice(dirs, func(i, j int) bool { return dirs[i].Size() < dirs[j].Size() })
+		tableheader = "<th><a href='?key=filename'>Filename</a></th><th><a href='?key=size&order=desc'>Size</a></th><th><a href='?key=date'>Date</a></th>"
+
+	case (key[0] == "size" && order[0] == "desc"):
+		sort.Slice(dirs, func(i, j int) bool { return dirs[i].Size() > dirs[j].Size() })
+		tableheader = "<th><a href='?key=filename'>Filename</a></th><th><a href='?key=size&order=asc'>Size</a></th><th><a href='?key=date'>Date</a></th>"
+
+	case (key[0] == "date" && order[0] == "asc"):
+		sort.Slice(dirs, func(i, j int) bool { return dirs[i].ModTime().UnixNano() < dirs[j].ModTime().UnixNano() })
+		tableheader = "<th><a href='?key=filename'>Filename</a></th><th><a href='?key=size'>Size</a></th><th><a href='?key=date&order=desc'>Date</a></th>"
+
+	case (key[0] == "date" && order[0] == "desc"):
+		sort.Slice(dirs, func(i, j int) bool { return dirs[i].ModTime().UnixNano() > dirs[j].ModTime().UnixNano() })
+		tableheader = "<th><a href='?key=filename'>Filename</a></th><th><a href='?key=size'>Size</a></th><th><a href='?key=date&order=asc'>Date</a></th>"
+
+	}
+
 	sort.Slice(dirs, func(i, j int) bool { return dirs[i].Name() < dirs[j].Name() })
 
 	w.Header().Set("Content-Type", "text/html; charset=utf-8")
-	fmt.Fprintf(w, "<table border='0'>\n<th>Filename</th><th>Size</th><th>Date</th></tr>")
+
+	fmt.Fprintf(w, "<table border='0'>%s\n", tableheader)
 	for _, d := range dirs {
 		name := d.Name()
 		if d.IsDir() {
@@ -69,7 +107,7 @@ func dirList(w http.ResponseWriter, r *http.Request, f http.File) {
 		// part of the URL path, and not indicate the start of a query
 		// string or fragment.
 		url := url.URL{Path: name}
-		fmt.Fprintf(w, "<tr><td><a href=\"%s\">%s</a></td><td>%d</td><td>%s</td></tr>", url.String(), htmlReplacer.Replace(name), d.Size(), d.ModTime().String())
+		fmt.Fprintf(w, "<tr><td><a href=\"%s\">%s</a></td><td>%d</td><td>%s</td></tr>", url.String(), htmlReplacer.Replace(name), d.Size(), d.ModTime().Format("2006-01-02 15:04:05"))
 
 		//		fmt.Fprintf(w, "<a href=\"%s\">%s</a>\n", url.String(), htmlReplacer.Replace(name))
 	}