# Copyright 1999-2007 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: $

#
# Original Author: Jim Ramsay <lack@gentoo.org>
# Purpose: Utility functions for 0install compatibility
#

# TODO: Install this all the time?
RDEPEND="rox-base/zeroinstall-injector"

# Environment:
NATIVE_FEED_DIR="/usr/share/0install.net/native_feeds"
ZEROINSTALL_STRIP_REQUIRES=""

# Escapes a http-style URI into a 0install-compatible filename
#
# 0install_escape_uri <uri>
#  uri - The URI to escape
0install_escape_uri() {
	local uri=${1}
	uri=${uri//\//#}
	echo $uri
}

# Parses an implementation, returning the interface URI
#
# 0install_parse_uri <src>
#  src - The XML document to parse
0install_parse_uri() {
	local src="${1}"

	[ -f "${src}" ] || die "Source file not found"
	local feed_for=$(grep '<feed-for.*interface=' "${src}")
	[ -n "${feed_for}" ] || die "No 'feed-for' element"
	feed_for=${feed_for##*interface=[\"\']}
	feed_for=${feed_for%[\'\"]*>}
	echo $feed_for
}

# Edits a feed, replacing stability and id
#
# 0install_edit_feed <input> <stability>
#  input  - The file to edit
#  output - The final install location (relative to ${D})
0install_edit_feed() {
	local input="${1}"; shift
	local output="${1}"; shift

	[ -f "${input}" ] || die "No input file"

	# Basic editing:
	#  - Remove stability="*"
	#  - Remove uri="*"
	#  - Replace id="*" with id=".", add in stability="packaged"
	#  - Force main="AppRun"
	sed -e 's/stability="[^"]*"//' \
		-e "s/stability='[^']*'//" \
	    -e 's/uri="[^"]*"//' \
	    -e "s/uri='[^']*'//" \
		-e 's/id="[^"]*"/id="." stability="packaged"/' \
		-e "s/id='[^']*'/id=\".\" stability=\"packaged\"/" \
		-e 's/main="[^"]*"/main="AppRun"/' \
		-e "s/main='[^']*'/main=\"AppRun\"/" \
		${input} > tmp.native_feed

	if [[ -n "${ZEROINSTALL_STRIP_REQUIRES}" ]]; then
		# Strip out all 'requires' sections
		sed -i -e '/<requires.*\/>/d' \
			-e '/<requires.*\>/,/<\/requires>/d' tmp.native_feed
	fi

	(
		insinto $(dirname ${output})
		newins tmp.native_feed $(basename ${output})
	)
}

# Installs an ebuild-provided feed 
#
# 0install_install_feed <src> <destpath>
#  src   - The XML file we will install and point at
#  path  - The path where the implementation will be installed 
#          IE, the final xml will be at <path>/<basename of src>
0install_install_feed() {
	local src="${1}"; shift
	local path="${1}"; shift
	local feedfile=$(basename "${src}")
	local dest="${path}/$feedfile"

	# Step 1: Find the URI
	local uri=$(0install_parse_uri "${src}")

	# Step 2: Install the feed in the proper location
	(
		insinto $(dirname "${dest}")
		newins "${src}" $(basename "${dest}")
	)

	# Step 3: Install the symlink so 0install can find it
	local feedname=$(0install_escape_uri ${uri})
	dosym "${dest}" "${NATIVE_FEED_DIR}/${feedname}"
}

# Does all the local feed magic you could want:
#   - Parses the input file to get the interface URI
#   - Edits the input file and installs it to the final location
#   - Installs a local feed pointer
#
# Environment variables:
#  ZEROINSTALL_STRIP_REQUIRES - If set, strips all 'requires' sections from the XML
#                            on editing.  Default: Not set
#
# 0install_native_feed <src> <destpath>
#  src   - The XML file we will edit, install, and point at
#  path  - The path where the implementation will be installed 
#          IE, the final edited xml will be at <path>/<basename of src>
0install_native_feed() {
	local src="${1}"; shift
	local path="${1}"; shift
	local feedfile=$(basename "${src}")
	local dest="${path}/$feedfile"

	# Step 1: Find the URI
	local uri=$(0install_parse_uri "${src}")

	# Step 2: Edit the input and install it in the proper location
	0install_edit_feed "${src}" "${dest}"

	# Step 3: Install the symlink so 0install can find it
	local feedname=$(0install_escape_uri ${uri})
	dosym "${dest}" "${NATIVE_FEED_DIR}/${feedname}"
}