qz: search Gentoo package on zugaina website

README.md

@@ -90,6 +90,7 @@ will create the symbolic link for each script in the \<path> directory.
 - [sync-date](scripts/sync-date) sets system time according to Google.
 - [xsmartlight](scripts/xsmartlight) allows to adjust ASUS smartscreen's brightness.
 - [use](scripts/use) shows Gentoo USE flag's description.
+- [qz](scripts/qz) looks for Gentoo packages on [http://gpo.zugaina.org](http://gpo.zugaina.org) website.
 
 ## Development tools
 

scripts/qz

@@ -0,0 +1,100 @@
+#!/bin/bash
+
+#
+# Поиск пакета Gentoo на сайте zugaina.
+#
+# Идея: https://megabaks.blogspot.com/2013/04/portage.html
+#
+
+set -e
+set -o errtrace
+trap stacktrace ERR
+
+\unalias -a
+
+IFS=$' \t\n'
+
+stacktrace() {
+	[ -n "$TRACED" ] && return
+
+	local depth=${#FUNCNAME[@]}
+
+	for ((i=1; i < "$depth"; i++)); do
+		printf '%*scall at %s:%s: %s()\n' "$i" '' \
+			"${BASH_SOURCE[$i]}" \
+			"${BASH_LINENO[$((i-1))]}" \
+			"${FUNCNAME[$i]}"
+	done
+
+	TRACED=true
+}
+
+die() {
+	echo -e "$@" >&2
+	exit 1
+}
+
+# ------------------------------------------------------------------------------
+
+join() {
+	paste -d " " - -
+}
+
+zxpath() {
+	curl -sq "$1" | xmllint --html --xpath "$2" - 2>&-
+}
+
+search_packages() {
+	zxpath "${ZUGAINA_URL}/Search?search=${1}" "//div[@id='search_results']/a/div/descendant::text()" | join
+}
+
+get_package_overlays() {
+	read -r category package_name rest <<<"$(qatom "$1")"
+
+	local packages
+	local pages
+
+	pages=$(zxpath "${ZUGAINA_URL}/${category}/${package_name}" "//a[contains(@href, '#')]/@href" \
+		| awk -F '/' '{printf "%s/%s\n", $2, $3}' \
+		| sort -u)
+
+	for page in $pages;do
+		packages=$(zxpath "${ZUGAINA_URL}/${page}" "//b[not(./a)]/text()|//b/a/text()" | join | sort --version-sort --reverse)
+
+		while read -r version overlay; do
+			OVERLAYS+="${category}/${version}:"${overlay//$'\n'/ }$'\n'
+		done <<<"$packages"
+	done
+}
+
+# ------------------------------------------------------------------------------
+
+[[ "${BASH_VERSINFO[0]}" -lt 5 ]] && die "ERROR: Bash >= 5 required."
+
+[[ -z "$1" ]] && die "USAGE: $(basename "$0") package"
+
+DEPENDENCIES=(xmllint awk)
+for dependency in "${DEPENDENCIES[@]}"; do
+	command -V "$dependency" >&- 2>&- || die "ERROR: The required '$dependency' command is not found."
+done
+
+green="\033[01;32m"
+rstc="\033[00m"
+
+ZUGAINA_URL="http://gpo.zugaina.org"
+
+while read -r package desc;do
+	echo -e "${green}${package}${rstc}: ${desc}"
+	get_package_overlays "$package"
+done < <(search_packages "$1")
+
+if [[ -n "${OVERLAYS}" ]]; then
+	echo -e ":"
+	echo -e "PACKAGE:REPOSITORY"
+	echo -e "-------:----------"
+	echo -e "${OVERLAYS}"
+	echo -e ":"
+else
+	die "Package '$1' not found."
+fi | column -t -s ':'
+