#!/bin/sh
# Prepare the site, then hand over to PHP-FPM.
#
# Three jobs, all of which have to survive an image upgrade without destroying
# anything the site owner did:
#
#   1. WordPress core and the fork's own plugins are copied out of the image
#      into the document root on every start, so rebuilding the image is a
#      real upgrade. Plugins and themes installed from the dashboard live in
#      their own volumes and are left alone.
#
#   2. wp-config.php is generated once, into a volume, and copied into place
#      each start. Never regenerated — new salts would end every session, and
#      a new SIRIUS_PRESS_KEY would make the stored publishing phrase
#      undecryptable, which looks exactly like a corrupted wallet.
#
#   3. Nothing waits on the network except the database, and that with a
#      bounded timeout: a site that will not start is worse than one that
#      starts and says the database is unreachable.

set -eu

DOCROOT=/var/www/html
SOURCE=/opt/sirius-press/core
CONFIG_STORE=/var/www/config/wp-config.php
CONFIG=$DOCROOT/wp-config.php

random_key() {
	# 64 characters of printable entropy. `tr -dc` over /dev/urandom is the one
	# method available in a slim image without adding tools.
	tr -dc 'A-Za-z0-9!@#%^&*()_+=-' < /dev/urandom | head -c 64
}

wait_for_db() {
	# Compose's healthcheck covers the container, but a first run also has to
	# wait out MariaDB's own initialisation.
	i=0
	while [ "$i" -lt 60 ]; do
		if php -r 'exit(@mysqli_connect(getenv("WORDPRESS_DB_HOST"), getenv("WORDPRESS_DB_USER"), getenv("WORDPRESS_DB_PASSWORD")) ? 0 : 1);' 2>/dev/null; then
			return 0
		fi
		i=$((i + 1))
		sleep 1
	done
	echo "sirius-press: the database did not answer within 60s; starting anyway" >&2
	return 1
}

# --------------------------------------------------------------------- core

# Copy everything except wp-content, which has volumes of its own, then put
# back the directories the fork owns. Anything the site owner installed from
# the dashboard sits in those same volumes and is never touched.
echo "sirius-press: syncing WordPress $(cat "$SOURCE/.sirius-core-version" 2>/dev/null || echo '?') into the document root"

for entry in "$SOURCE"/*; do
	name="$(basename "$entry")"
	if [ "$name" = "wp-content" ]; then
		continue
	fi
	rm -rf "${DOCROOT:?}/${name}"
	cp -R "$entry" "$DOCROOT/"
done
cp "$SOURCE/.sirius-core-version" "$DOCROOT/.sirius-core-version" 2>/dev/null || true

mkdir -p "$DOCROOT/wp-content/plugins" "$DOCROOT/wp-content/themes" "$DOCROOT/wp-content/mu-plugins" "$DOCROOT/wp-content/uploads"

# Seed bundled themes only when the themes volume is empty — replacing them on
# every start would undo a site owner's edits to a bundled theme.
if [ -z "$(ls -A "$DOCROOT/wp-content/themes" 2>/dev/null)" ]; then
	cp -R "$SOURCE/wp-content/themes/." "$DOCROOT/wp-content/themes/" 2>/dev/null || true
fi

# The fork's own plugins are the image's to own, and are replaced outright.
for dir in "$SOURCE"/wp-content/plugins/sirius-press-*/; do
	[ -d "$dir" ] || continue
	name="$(basename "$dir")"
	rm -rf "${DOCROOT:?}/wp-content/plugins/${name}"
	cp -R "$dir" "$DOCROOT/wp-content/plugins/"
done
cp "$SOURCE"/wp-content/mu-plugins/*.php "$DOCROOT/wp-content/mu-plugins/" 2>/dev/null || true

# Everything else WordPress ships in wp-content (akismet, the index.php
# guards) only needs to exist once.
for extra in akismet index.php; do
	if [ ! -e "$DOCROOT/wp-content/plugins/$extra" ] && [ -e "$SOURCE/wp-content/plugins/$extra" ]; then
		cp -R "$SOURCE/wp-content/plugins/$extra" "$DOCROOT/wp-content/plugins/"
	fi
done

chown -R www-data:www-data "$DOCROOT"

# ---------------------------------------------------------------- wp-config

if [ ! -f "$CONFIG_STORE" ]; then
	echo "sirius-press: generating wp-config.php"

	: "${WORDPRESS_DB_HOST:=db}"
	: "${WORDPRESS_DB_NAME:=wordpress}"
	: "${WORDPRESS_DB_USER:=wordpress}"
	: "${WORDPRESS_DB_PASSWORD:=wordpress}"
	: "${WORDPRESS_TABLE_PREFIX:=wp_}"
	if [ -z "${SIRIUS_PRESS_KEY:-}" ]; then
		SIRIUS_PRESS_KEY="$(random_key)"
	fi

	mkdir -p "$(dirname "$CONFIG_STORE")"
	{
		echo "<?php"
		echo "// Generated by the Sirius Press container on first start."
		echo "// Edit freely — this file is kept in a volume and never rewritten."
		echo
		echo "define( 'DB_NAME', '${WORDPRESS_DB_NAME}' );"
		echo "define( 'DB_USER', '${WORDPRESS_DB_USER}' );"
		echo "define( 'DB_PASSWORD', '${WORDPRESS_DB_PASSWORD}' );"
		echo "define( 'DB_HOST', '${WORDPRESS_DB_HOST}' );"
		echo "define( 'DB_CHARSET', 'utf8mb4' );"
		echo "define( 'DB_COLLATE', '' );"
		echo
		for k in AUTH_KEY SECURE_AUTH_KEY LOGGED_IN_KEY NONCE_KEY \
			AUTH_SALT SECURE_AUTH_SALT LOGGED_IN_SALT NONCE_SALT; do
			echo "define( '${k}', '$(random_key)' );"
		done
		echo
		echo "// The key the publishing phrase is encrypted with. Separate from"
		echo "// the auth salts so rotating sessions does not orphan the stored"
		echo "// key. Lose this and the phrase must be entered again."
		echo "define( 'SIRIUS_PRESS_KEY', '${SIRIUS_PRESS_KEY}' );"
		echo
		echo "// nginx terminates TLS in front of this container, so PHP has to"
		echo "// be told. Without it WordPress builds http:// URLs and a"
		echo "// redirect loop follows."
		echo "if ( isset( \$_SERVER['HTTP_X_FORWARDED_PROTO'] ) && 'https' === \$_SERVER['HTTP_X_FORWARDED_PROTO'] ) {"
		echo "	\$_SERVER['HTTPS'] = 'on';"
		echo "}"
		echo "define( 'SIRIUS_PRESS_TRUST_PROXY', true );"
		echo
		if [ -n "${WORDPRESS_SITE_URL:-}" ]; then
			echo "define( 'WP_HOME', '${WORDPRESS_SITE_URL}' );"
			echo "define( 'WP_SITEURL', '${WORDPRESS_SITE_URL}' );"
		fi
		echo "define( 'FS_METHOD', 'direct' );"
		echo "define( 'WP_DEBUG', ${WORDPRESS_DEBUG:-false} );"
		echo
		echo "\$table_prefix = '${WORDPRESS_TABLE_PREFIX}';"
		echo
		echo "if ( ! defined( 'ABSPATH' ) ) {"
		echo "	define( 'ABSPATH', __DIR__ . '/' );"
		echo "}"
		echo "require_once ABSPATH . 'wp-settings.php';"
	} > "$CONFIG_STORE"
	chmod 640 "$CONFIG_STORE"
fi

cp "$CONFIG_STORE" "$CONFIG"
chown www-data:www-data "$CONFIG"
chmod 640 "$CONFIG"


if [ "${1:-}" = "php-fpm" ]; then
	wait_for_db || true
fi

exec "$@"