index pages use source file birth instead of output

this was a bug introduced with index pages for subsections

rivet.sh

@@ -170,10 +170,7 @@ rm -f "$destdir"/_header.html "$destdir"/_footer.html "$destdir"/_metadata.html
 
 # Generate an ordered (by open time) file list
 find "$srcdir" -type f -exec ls -1t {} + | awk '/^.*\/[^_].+\.(md|html)$/' > "$objlist"
-rm -f "$objdate"
-while IFS="" read -r file; do
-	stat -c '%y' "$file" >>  "$objdate"
-done < "$objlist"
+
 sed -e "s,^\/*[^\/]*\/,$destdir/," "$objlist" > "$tmpsed"
 mv "$tmpsed" "$objlist"
 
@@ -206,17 +203,27 @@ if ! [ "$SKIP_LIST" ]; then
     lobjlist=$(mktemp)
     lobjdate=$(mktemp)
     llinklist=$(mktemp)
-    for indexf in $(find "$destdir" -type f -iname "index.html"); do
+    lmdlist=$(mktemp)
+
+    for indexf in $(find "$destdir" -mindepth 1 -type f -iname "index.html"); do
 	outdir=$(echo $(dirname "$indexf") | sed "s/$destdir//g")
 
 # Generate an ordered (by open time) list of files in the subdirectory by filtering the global list
+# Filter global list
 	grep "$outdir" "$objlist" > "$lobjlist"
 	sed -e "s,^\/*[^\/]*\/,$destdir/," "$lobjlist" > "$tmpsed"
+	mv "$tmpsed" "$lobjlist"
+
+# Get the corresponding .md source file for every .html file, so that the file date is referring to
+# the source and not to the output
+	sed -e 's/\.html$/\.md/' "$lobjlist" > "$tmpsed"
+	sed -e "s/$destdir/$srcdir/" "$tmpsed" > "$lmdlist"
+
+# Generate the list of dates for each file (open time)
 	rm -f "$lobjdate"
 	while IFS="" read -r file; do
 		stat -c '%y' "$file" >>  "$lobjdate"
-	done < "$lobjlist"
-	mv "$tmpsed" "$lobjlist"
+	done < "$lmdlist"
 
 	grep "$outdir" "$linklist" > "$llinklist"