#!/bin/sh

# Registration, plus the two symlinks that expose what the admin uploads (a third, the pattern, is
# deliberately NOT one — see below). Nothing here migrates a router off an older footstrap: OpenWrt
# expects a sysupgrade rather than a package upgrade — the one exception is the stale pattern
# symlink itself, removed below because leaving it would keep a reported security hole open.

changed=0

set_opt() {
	uci -q get "luci.$1" >/dev/null 2>&1 && return
	uci set "luci.$1=$2"
	changed=1
}

set_opt themes.Footstrap /luci-static/footstrap

# A fresh install may pick the theme; an upgrade must never move a router off the theme it is on.
# `changed` is what tells the two apart — on an upgrade the entry is already there — and it has to
# carry the decision alone, because apk exports no PKG_UPGRADE.
if [ "${PKG_UPGRADE:-}" != 1 ] && [ "$changed" = 1 ]; then
	set_opt main.mediaurlbase /luci-static/footstrap
fi

[ "$changed" = 1 ] && uci commit luci

# uhttpd serves /www only, so the admin's uploads live in /etc — where a sysupgrade keeps them
# (lib/upgrade/keep.d) — and are reached through symlinks, EXCEPT the pattern (below).
#
# The pattern is deliberately NOT symlinked into /www: an SVG is a document, and served as one
# through a plain same-origin URL it runs as a script with the admin's session (OpenWrt forum
# thread 251930). It is instead read by cgi-bin/luci-theme-footstrap-pattern, which answers with
# CSP 'none' + sandbox and nosniff — headers uhttpd cannot attach to a static file. The login
# background stays a plain symlink: fs-assets.js re-encodes every upload to a JPEG on a canvas
# first, so there is no script grammar left in the bytes for a direct hit to run.
mkdir -p /etc/footstrap
if [ -d /www/luci-static/footstrap ]; then
	ln -sf /etc/footstrap/login-bg /www/luci-static/footstrap/bg
	ln -sfn /etc/footstrap/fonts /www/luci-static/footstrap/fonts
fi
# Clean up a pre-0.15 install's stale pattern symlink — see the header comment above for why this
# is the one migration this script makes. `-L` only: never remove a real file some other install
# step could have left at that path.
[ -L /www/luci-static/footstrap/pattern.svg ] && rm -f /www/luci-static/footstrap/pattern.svg

exit 0