allow specifying file output name

bookmobile

@@ -16,9 +16,9 @@ end
 function usage
   echo "Bookmobile: Simple command line script to download articles for offline reading as html, epub or markdown. Saves a simplified html document to current directory as default." 
   echo ""
-  echo "Optionally, you can specify a theme, format and output directory"
+  echo "Optionally, you can specify a theme, format, filename and output directory"
   echo ""
-  echo "Usage: ./bookmobile url [ --theme THEME ] [ --format FORMAT ] [ --output OUTPUT ]" 
+  echo "Usage: ./bookmobile url [ --theme THEME ] [ --format FORMAT ] [ --name FILENAME ] [ --output OUTPUT ]" 
   echo "                    [-h | --help ]"
   echo ""
   echo "Options:"
@@ -37,6 +37,9 @@ function usage
   echo "    -f FORMAT  Set file format (html, reader, markdown, epub)"
   echo "               default: html"
   echo ""
+  echo "    --name  NAME" 
+  echo "    -n NAME Set specified file name instead of defaulting to article title"
+  echo ""
   echo "    --output OUTPUT" 
   echo "    -o OUTPUT  Set output location"
   echo "               default: current directory"
@@ -44,7 +47,7 @@ function usage
 end
 
 function check_args
-  argparse h/help t/theme= f/format= o/output= -- $argv
+  argparse h/help t/theme= f/format= n/name= o/output= -- $argv
   or exit 1
 
   if set -q _flag_help
@@ -60,6 +63,10 @@ function check_args
     set format $_flag_format
   end
 
+  if set -q _flag_n
+    set -g name $_flag_name
+  end
+
   if set -q _flag_o
     set output $_flag_output
   end
@@ -71,7 +78,11 @@ function set_metadata
 
   set -g title (readable $url --properties "title")
 
-  if test -z "$title" #if title was empty, set title to date time 
+  if test -n "$name" #check if title specified by user
+    
+    set -g title $name
+
+  else if test -z "$title" #if title was empty, set title to date time 
 
     set -g title (date "+%Y-%m-%d_%H:%M:%S")