#!/usr/bin/env bash
set -euo pipefail
cd "$(dirname "$0")/.."

if [[ "${1:-}" != "--inside" ]]; then
	exec timeout --signal=TERM --kill-after=5s 150s unshare --mount --fork --kill-child=TERM "$0" --inside
fi

name="mysql-pool-idle-test-$$"
root="/tmp/$name"
site="$root/site"
work="$root/work"
settings="$root/settings.cfg"
log="$root/service.log"
socket="$root/run/cli.sock"
test_user="uce_pool_idle_$$"
test_database="uce_pool_idle_$$"
test_password=$(printf '%s' "$name-$(date +%s%N)" | sha256sum | cut -c1-32)
server_pid=""

cleanup() {
	status=$?
	if [[ -n "$server_pid" ]] && kill -0 "$server_pid" 2>/dev/null; then
		kill -TERM "$server_pid" 2>/dev/null || true
		deadline=$((SECONDS + 10))
		while kill -0 "$server_pid" 2>/dev/null && (( SECONDS < deadline )); do sleep 0.05; done
		if kill -0 "$server_pid" 2>/dev/null; then kill -KILL "$server_pid" 2>/dev/null || true; fi
		wait "$server_pid" 2>/dev/null || true
	fi
	mariadb -e "DROP DATABASE IF EXISTS \`$test_database\`; DROP USER IF EXISTS '$test_user'@'127.0.0.1'" >/dev/null 2>&1 || true
	if (( status != 0 )) && [[ -r "$log" ]]; then cat "$log" >&2; fi
	rm -rf "$root"
	return "$status"
}
trap cleanup EXIT

mkdir -p "$site" "$work" "$root/run" "$root/session" "$root/upload"
cp /etc/uce/settings.cfg "$settings"
cat >>"$settings" <<CFG
BIN_DIRECTORY=$work
PRECOMPILE_FILES_IN=$site
SITE_DIRECTORY=$site
FCGI_SOCKET_PATH=$root/run/fastcgi.sock
FCGI_PORT=
CLI_SOCKET_PATH=$socket
WS_BROKER_SOCKET_PATH=$root/run/ws.sock
HTTP_PORT=
HTTP_DOCUMENT_ROOT=$site
SESSION_PATH=$root/session
TMP_UPLOAD_PATH=$root/upload
WASM_CORE_PATH=$(pwd)/bin/wasm/core.wasm
WORKER_COUNT=1
PROACTIVE_COMPILE_ENABLED=0
MYSQL_PERSISTENT_POOL_SIZE=8
MYSQL_PERSISTENT_POOL_IDLE_TIMEOUT_SECONDS=2
CFG
mount --bind "$settings" /etc/uce/settings.cfg

mariadb -e "DROP DATABASE IF EXISTS \`$test_database\`; DROP USER IF EXISTS '$test_user'@'127.0.0.1'; CREATE DATABASE \`$test_database\`; CREATE USER '$test_user'@'127.0.0.1' IDENTIFIED BY '$test_password'; GRANT ALL ON \`$test_database\`.* TO '$test_user'@'127.0.0.1'"

cat >"$site/database.uce" <<UCE
CLI(Request& context)
{
	MySQL* db = mysql_connect("127.0.0.1", "$test_user", "$test_password", "$test_database");
	if(!mysql_connected(db)) { print("connect-failed"); return; }
	String connection_id;
	mysql_query(db, "SELECT CONNECTION_ID() AS id").each([&](DValue row, String key) { connection_id = row["id"].to_string(); });
	String source;
	DValue perf = request_perf();
	perf["mysql_operations"].each([&](DValue operation, String key) {
		if(operation["op"].to_string() == "connect") source = operation["source"].to_string();
	});
	print(perf["worker_pid"].to_string(), "|", connection_id, "|", source);
	mysql_disconnect(db);
}
UCE
printf '%s\n' 'CLI(Request& context) { print(request_perf()["worker_pid"].to_string(), "|plain"); }' >"$site/plain.uce"

timeout --signal=TERM --kill-after=5s 120s bin/uce_fastcgi.linux.bin >"$log" 2>&1 &
server_pid=$!
deadline=$((SECONDS + 20))
while [[ ! -S "$socket" ]] && (( SECONDS < deadline )); do sleep 0.05; done
[[ -S "$socket" ]] || { echo "private UCE CLI socket was not ready" >&2; exit 1; }

request() {
	timeout --signal=TERM --kill-after=1s 30s scripts/uce-cli --socket "$socket" "$1"
}

first=$(request /database.uce)
second=$(request /database.uce)
IFS='|' read -r first_pid first_id first_source <<<"$first"
IFS='|' read -r second_pid second_id second_source <<<"$second"
[[ "$first_source" == "new" && "$second_source" == "worker" ]]
[[ "$first_pid" == "$second_pid" && "$first_id" == "$second_id" ]]

sleep 3
plain=$(request /plain.uce)
[[ "$plain" == "$first_pid|plain" ]]
deadline=$((SECONDS + 5))
while (( SECONDS < deadline )); do
	connections=$(mariadb --batch --skip-column-names -e "SELECT COUNT(*) FROM information_schema.PROCESSLIST WHERE USER='$test_user'")
	[[ "$connections" == "0" ]] && break
	sleep 0.05
done
[[ "$connections" == "0" ]] || { echo "expired pooled connection remained after a request boundary" >&2; exit 1; }

third=$(request /database.uce)
IFS='|' read -r third_pid third_id third_source <<<"$third"
[[ "$third_pid" == "$first_pid" && "$third_source" == "new" && "$third_id" != "$first_id" ]]

echo "Persistent MySQL idle eviction preserved hot reuse and retired the expired connection"