# Copyright (c) 2017 The NetBSD Foundation, Inc.
# All rights reserved.
#
# This code is derived from software contributed to The NetBSD Foundation
# by Johnny C. Lam.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
# NAME
#	icon_themes.subr -- icon theme cache management for packages
#
# SYNOPSIS
#	task_icon_themes [-s] add | remove <stage>
#
# DESCRIPTION
#	The task_icon_themes function supports two actions, "add" and
#	"remove", that will add or remove the GTK+ icon caches from the
#	theme directories.
#
#	The available options are as follows:
#
#	-s	Silent; don't write to standard output.
#
#	The task_icon_themes function reads standard input line by line
#	and looks for lines of the form:
#
#	    # ICON_THEME: <themedir>
#
#	If the path to the theme directory is relative, then it is assumed
#	to be relative to ${PKG_PREFIX}/share/icons.
#
# RETURN VALUES
#	Returns 0 if the action is successful for all icon themes, and >0
#	if an error occurs.
#
# ENVIRONMENT
#	The following variables are used if they are set:
#
#	GTK_UPDATE_ICON_CACHE
#		The name or path to the GTK+ command to update the icon
#		caches.  This is the fall-through default command if
#		neither of the other two gtk-update-icon-cache(1)
#		commands exist on the system.
#
#	GTK2_UPDATE_ICON_CACHE
#		The name or path to the GTK+-2.x command to update the
#		icon caches.
#
#	GTK3_UPDATE_ICON_CACHE
#		The name or path to the GTK+-3.x command to update the
#		icon caches.
#
#	PKGNAME
#		The name of the package.
#
#	PKG_DESTDIR
#		A "destdir" prefix that is prepended to all filesystem
#		paths.  The default value is the empty string.
#
#	PKG_PREFIX
#		The installation prefix of the package.  The default is
#		"/usr/pkg".
#
#	RM	The name or path to the rm(1) utility.
#
#	TASK_MSG
#		String prepended to all normal message written to
#		standard output.
#

__task_icon_themes__="yes"

task_load echo
task_load which

task_icon_themes()
{
	: ${RM:=rm}

	: ${PKG_PREFIX:=/usr/pkg}
	: ${PKGNAME:=${0##*/}}
	: ${TASK_MSG:=""}

	local arg
	local echo="task_echo"
	local OPTIND=1
	while getopts ":s" arg "$@"; do
		case $arg in
		s)	echo=":" ;;
		*)	return 127 ;;
		esac
	done
	shift $(( ${OPTIND} - 1 ))
	[ $# -gt 0 ] || return 127

	local action="$1"; shift
	local stage="$1"

	case $action in
	add|remove)
		: "valid action" ;;
	*)	return 0 ;;
	esac

	# Guard against ${PKG_PREFIX} == "/".
	local prefix
	case ${PKG_PREFIX}/ in
	//)	prefix= ;;
	*)	prefix=${PKG_PREFIX} ;;
	esac

	local result=0
	local hash tag themedir
	local theme cache update_cmd
	while read hash tag themedir; do
		# Filter for "# ICON_THEME:"
		case $hash/$tag in
		"#/ICON_THEME:")
			: "use this line" ;;
		*)	continue ;;
		esac

		# Canonicalize paths.
		case $themedir in
		"")	# skip lines without required args
			continue ;;
		[!/]*)	themedir="$prefix/share/icons/$themedir" ;;
		esac
		themedir="${PKG_DESTDIR}$themedir"
		theme="$themedir/index.theme"
		cache="$themedir/icon-theme.cache"

		case "$action,$stage" in
		remove,postremove)
			: "avoid double removal of icon caches" ;;
		remove,*)
			if [ ! -f "$cache" ]; then
				$echo "${TASK_MSG}> icon cache already removed: $themedir"
			elif ${RM} -f "$cache"; then
				$echo "${TASK_MSG}> icon cache removed: $themedir"
			else
				$echo "${TASK_MSG}! icon cache not removed: $themedir"
				result=1
			fi ;;
		esac

		# Update the icon caches during "add" action, but also during
		# "remove" action at "postremove" stage if the theme directories
		# still exist.
		#
		case "$action,$stage" in
		add,*|remove,postremove)
			# Set the command used to update the icon caches.
			_task_icon_themes_cache_update_cmd
			if [ "$__task_icon_themes_update_cmd__" != "missing" ]; then
				update_cmd="$__task_icon_themes_update_cmd__"
			fi
			: ${update_cmd:=${GTK_UPDATE_ICON_CACHE:-true}}

			if [ ! -f "$theme" ]; then
				case $action in
				add)	$echo "${TASK_MSG}! icon theme missing: $themedir"
					result=1 ;;
				remove)	: "silently skip updating" ;;
				esac
			elif [ -z "$update_cmd" ]; then
				$echo "${TASK_MSG}! icon theme not cached - missing command: $themedir"
				result=1
			elif $update_cmd -f -q "$themedir"; then
				$echo "${TASK_MSG}> icon theme cached: $themedir"
			else
				$echo "${TASK_MSG}! icon theme not cached: $themedir"
				result=1
			fi ;;
		esac
	done
	return $result
}

_task_icon_themes_cache_update_cmd()
{
	: ${GTK2_UPDATE_ICON_CACHE:=gtk2-update-icon-cache}
	: ${GTK3_UPDATE_ICON_CACHE:=gtk-update-icon-cache}

	# Cache gtk-update-icon-cache(1) location.
	if [ -z "$__task_icon_themes_update_cmd__" ]; then
		local cmd
		for cmd in \
			"${GTK3_UPDATE_ICON_CACHE}" \
			"${GTK2_UPDATE_ICON_CACHE}"
		do
			[ -n "$cmd" ] || continue
			__task_icon_themes_update_cmd__=$( task_which "$cmd" )
			[ -z "$__task_icon_themes_update_cmd__" ] || break
		done
		[ -n "$__task_icon_themes_update_cmd__" ] ||
			__task_icon_themes_update_cmd__="missing"
	fi
}

# Static variable for the path to the command that updates the icon cache.
__task_icon_themes_update_cmd__=