[particles] add handle-package-moves.sh

It makes handling package moves in profiles/updates easier.
Requires modify.pl which is currently in particles git repository.

handle-package-moves.sh

@@ -0,0 +1,109 @@
+#!/bin/bash
+
+# Updates particles using profiles/updates.
+# Arguments: file name(s) to profiles/updates/*.
+# example: this-script /usr/portage/profiles/updates/*-2012
+
+# Assumes that packages with category foo-bar are in foo-bar.particle
+# under $particles_dir.
+
+# (C) 2012 Sławomir Nizio <slawomir.nizio#sabayon.org>
+# this scripty is placed in public domain
+
+# path to the glourious script or name if in PATH
+modify_script=${modify_script:-modify.pl}
+
+# for example: particles.git/weekly
+# default value is useful when it's run from particles.git directory
+particles_dir=${particles_dir:-weekly}
+
+# don't edit this
+available_after_move=()
+
+if [[ $# -eq 0 ]]; then
+	echo "$0 FILE [FILE...]" >&2
+	echo "FILE = 4Q-2012, for example" >&2
+	exit 1
+fi
+
+start() {
+	if ! "$modify_script" --help > /dev/null; then
+		echo "Looks that I can't execute $modify_script." >&2
+		echo "Check if you have that script and adjust \$PATH" >&2
+		echo "or \$modify_script if needed."
+		exit 1
+	fi
+	if ! cd "$particles_dir"; then
+		echo "cd $particles_dir = nope" >&2
+		exit 1
+	fi
+	for file in "$@"; do
+		readfileanddostuff "$file" || { echo "aborted"; exit 1; }
+	done
+	if [[ ${#available_after_move[@]} -gt 0 ]]; then
+		# Here it can print invalid package names if a package was
+		# renamed multiple times, or just removed since.
+		echo
+		echo "new candidates"
+		echo "These are packages that weren't present in a particle before"
+		echo "their rename, and a particle for their category exists."
+		echo "Displaying them in case it's useful (whitespace separated)."
+		echo "Check if they refer to packages that are really available!"
+		echo "${available_after_move[@]}"
+	else
+		echo
+		echo "No new candidates."
+	fi
+}
+
+readfileanddostuff() {
+	local file=$1
+	local old new
+	local oldcat newcat
+
+	echo "** $file **"
+	if [[ ! -r $file ]]; then
+		echo "$file doesn't exist or can't be read, or is invalid type" >&2
+		return 1
+	fi
+	while read op old new; do
+		[[ $op = move ]] || continue
+		echo "@@@ $old -> $new"
+		oldcat=${old%/*}
+		newcat=${new%/*}
+		# echo "<$oldcat,$newcat>"
+		if [[ ! -f $oldcat.particle ]]; then
+			echo "no-file-old $oldcat.particle, skipping"
+			continue
+		fi
+
+		# modify.pl currently returns success when no entry to be deleted
+		# so we use this to know if new (replaced) entry should be added
+		# or not
+		if egrep -q "^\s*$old(,|$)" "$oldcat.particle"; then
+			# removed even if new name won't be added
+			"$modify_script" --noask --delete "$oldcat.particle" "$old"
+			was_present=1
+		else
+			was_present=0
+		fi
+
+		if [[ ! -f $newcat.particle ]]; then
+			echo "no-file-new $newcat.particle, skipping the rest"
+			continue
+		fi
+
+		if [[ $was_present = 1 ]]; then
+			"$modify_script" --noask "$newcat.particle" "$new"
+		else
+			# if it wasn't there before (and it's not now) and a particle
+			# for this category exists (checked above), inform about it
+			# maybe someone would want to add it
+			if ! egrep -q "^\s*$new(,|$)" "$newcat.particle"; then
+				available_after_move+=( "$new" )
+			fi
+		fi
+	done < "$file"
+}
+
+start "$@"