From d295d6860965622d7e565d3edc2f29a234aa527c Mon Sep 17 00:00:00 2001
From: Rok Garbas <rok@garbas.si>
Date: Sat, 3 Dec 2016 17:43:38 +0100
Subject: [PATCH] firefox-bin: updated the updateScript with suggestions from
 @Mic92

also added some comments to the update script so that a new person
looking at it know what is happening
---
 .../browsers/firefox-bin/default.nix          | 50 +++++++++++++++----
 1 file changed, 39 insertions(+), 11 deletions(-)

diff --git a/pkgs/applications/networking/browsers/firefox-bin/default.nix b/pkgs/applications/networking/browsers/firefox-bin/default.nix
index dd767d6984f6..d828a5486fd6 100644
--- a/pkgs/applications/networking/browsers/firefox-bin/default.nix
+++ b/pkgs/applications/networking/browsers/firefox-bin/default.nix
@@ -184,6 +184,17 @@ stdenv.mkDerivation {
 
         tmpfile=`mktemp`
         url=http://archive.mozilla.org/pub/firefox/releases/
+
+        # retriving latest released version
+        #  - extracts all links from the $url
+        #  - removes . and ..
+        #  - this line remove everything not starting with a number
+        #  - this line sorts everything with semver in mind
+        #  - we remove lines that are mentioning funnelcake
+        #  - this line removes beta version if we are looking for final release
+        #    versions or removes release versions if we are looking for beta
+        #    versions
+        # - this line pick up latest release
         version=`xidel -q $url --extract "//a" | \
                  sed s"/.$//" | \
                  grep "^[0-9]" | \
@@ -191,22 +202,39 @@ stdenv.mkDerivation {
                  grep -v "funnelcake" | \
                  grep -e "${if isBeta then "b" else ""}\([[:digit:]]\|[[:digit:]][[:digit:]]\)$" | ${if isBeta then "" else "grep -v \"b\" |"} \
                  tail -1`
+
+        # this is a list of sha512 and tarballs for both arches
         shasums=`curl --silent $url$version/SHA512SUMS`
 
-        echo "{" > $tmpfile
-        echo "  version = \"$version\";" >> $tmpfile
-        echo "  sources = [" >> $tmpfile
+        cat > $tmpfile <<EOF
+        {
+          version = "$version";
+          sources = [
+        EOF
         for arch in linux-x86_64 linux-i686; do
-            for line in `echo "$shasums" | grep $arch | grep "firefox-$version.tar.bz2$" | tr " " ":"`; do
-            echo "    { url = \"$url$version/$arch/`echo $line | cut -d\":\" -f3`\";" >> $tmpfile
-            echo "      locale = \"`echo $line | cut -d\":\" -f3 | sed \"s/$arch\///\" | sed \"s/\/.*//\"`\";" >> $tmpfile
-            echo "      arch = \"$arch\";" >> $tmpfile
-            echo "      sha512 = \"`echo $line | cut -d\":\" -f1`\";" >> $tmpfile
-            echo "    }" >> $tmpfile
+          # retriving a list of all tarballs for each arch
+          #  - only select tarballs for current arch
+          #  - only select tarballs for current version
+          #  - rename space with colon so that for loop doesnt
+          #  - inteprets sha and path as 2 lines
+          for line in `echo "$shasums" | \
+                       grep $arch | \
+                       grep "firefox-$version.tar.bz2$" | \
+                       tr " " ":"`; do
+            # create an entry for every locale
+            cat >> $tmpfile <<EOF
+            { url = "$url$version/$arch/`echo $line | cut -d":" -f3`";"
+              locale = "`echo $line | cut -d":" -f3 | sed "s/$arch\///" | sed "s/\/.*//"`";
+              arch = "$arch";
+              sha512 = "`echo $line | cut -d":" -f1`";
+            }
+        EOF
           done
         done
-        echo "  ];" >> $tmpfile
-        echo "}" >> $tmpfile
+        cat >> $tmpfile <<EOF
+            ];
+        }
+        EOF
 
         cat $tmpfile > ${if isBeta then "beta_" else ""}sources.nix