#!/bin/bash

set -e

HEALTHCHECK_MARKER=/tmp/skip_healthcheck
touch $HEALTHCHECK_MARKER
MIGRATION_MARKER=$PGDATA/migration_in_progress
OLDDATA=$PGDATA/old_data
NEWDATA=$PGDATA/new_data

install_old_postgres_debian() {
  ## TODO: Replace with script from outline entrypoint
  apt-get update
  apt-get install -y git
  git clone https://github.com/theory/pgenv.git /tmp/pgenv
  cd /tmp/pgenv
  export PATH="/tmp/pgenv/bin:/tmp/pgenv/pgsql/bin:$PATH"

  # Install missing packages
  apt-get install -y make curl patch gcc sudo libreadline-dev zlib1g-dev build-essential
  pgenv check
  LATEST_OLD_VERSION=$(pgenv available $DATA_VERSION | grep -oE "$DATA_VERSION\.[0-9]+" | tail -n 1)
  pgenv build $LATEST_OLD_VERSION
}

install_old_postgres_alpine() {
  apk add git
  git clone https://github.com/theory/pgenv.git /tmp/pgenv
  cd /tmp/pgenv
  export PATH="/tmp/pgenv/bin:/tmp/pgenv/pgsql/bin:$PATH"

  #Install Missing pagckages:
  apk add make curl make patch gcc alpine-sdk sudo readline-dev build-base zlib-dev linux-headers
  pgenv check
  LATEST_OLD_VERSION=$(pgenv available $DATA_VERSION | grep -oE "$DATA_VERSION\.[0-9]+" | tail -n 1)
  pgenv build $LATEST_OLD_VERSION
}

if [ -e $MIGRATION_MARKER ]; then
  echo "FATAL: migration was started but did not complete in a previous run. manual recovery necessary"
  exit 1
fi

if [ -f $PGDATA/PG_VERSION ]; then
  DATA_VERSION=$(cat $PGDATA/PG_VERSION)

  if [ -n "$DATA_VERSION" -a "$PG_MAJOR" != "$DATA_VERSION" ]; then
    echo "postgres data version $DATA_VERSION found, but need $PG_MAJOR. Starting migration"
    echo "Installing postgres $DATA_VERSION"
    if [ -f /etc/alpine-release ]; then
      install_old_postgres_alpine
    else
      install_old_postgres_debian
    fi
    echo "shuffling around"
    gosu postgres mkdir $OLDDATA $NEWDATA
    chmod 700 $OLDDATA $NEWDATA
    mv $PGDATA/* $OLDDATA/ || true
    touch $MIGRATION_MARKER
    echo "running initdb"
    # abuse entrypoint script for initdb by making server error out
    gosu postgres bash -c "export PGDATA=$NEWDATA ; /usr/local/bin/docker-entrypoint.sh --invalid-arg || true"
    echo "running pg_upgrade"
    cd /tmp
    gosu postgres pg_upgrade --link -b /tmp/pgenv/pgsql-$LATEST_OLD_VERSION/bin -d $OLDDATA -D $NEWDATA -U $POSTGRES_USER
    cp $OLDDATA/pg_hba.conf $NEWDATA/
    mv $NEWDATA/* $PGDATA
    rm -rf $OLDDATA
    rmdir $NEWDATA
    rm $MIGRATION_MARKER
    echo "migration complete"
  fi
fi

rm $HEALTHCHECK_MARKER

/usr/local/bin/docker-entrypoint.sh postgres