#!/bin/bash

set -euxo pipefail

PG_BIN=$1
WAL_PATH=$2
DATA_DIR=$3
PORT=$4
SYSID=$(od -A n -j 24 -N 8 -t d8 "$WAL_PATH"/000000010000000000000002* | cut -c 3-)
rm -fr "$DATA_DIR"
env -i LD_LIBRARY_PATH="$PG_BIN"/../lib "$PG_BIN"/initdb -E utf8 -U cloud_admin -D "$DATA_DIR" --sysid="$SYSID"
echo port="$PORT" >> "$DATA_DIR"/postgresql.conf
REDO_POS=0x$("$PG_BIN"/pg_controldata -D "$DATA_DIR" | grep -F "REDO location"| cut -c 42-)
declare -i WAL_SIZE=$REDO_POS+114
"$PG_BIN"/pg_ctl -D "$DATA_DIR" -l logfile start
"$PG_BIN"/pg_ctl -D "$DATA_DIR" -l logfile stop -m immediate
cp "$DATA_DIR"/pg_wal/000000010000000000000001 .
cp "$WAL_PATH"/* "$DATA_DIR"/pg_wal/
for partial in "$DATA_DIR"/pg_wal/*.partial ; do mv "$partial" "${partial%.partial}" ; done
dd if=000000010000000000000001 of="$DATA_DIR"/pg_wal/000000010000000000000001 bs=$WAL_SIZE count=1 conv=notrunc
rm -f 000000010000000000000001