#!/bin/sh

set -e

INI="/etc/hhvm/server.ini"

usage() {
  echo "Usage: $0 enable root-dir"
  echo "       $0 disable"
  echo
  echo "Enables HHVM's \"repo authoritative\" mode. In this mode, HHVM"
  echo "uses a pre-built and pre-optimized version of your PHP or Hack"
  echo "source code. These ahead-of-time optimizations mean that code run"
  echo "in repo mode can be significantly faster. Keep in mind that after"
  echo "this mode is enabled, source code is no longer consulted, so"
  echo "changes there will not be reflected unless this command is re-run"
  echo "to either rebuild the repo or disable repo authoritative mode."
  echo
  echo "This command changes HHVM configuration; you will probably need"
  echo "to be root."
  echo
  echo
  echo "$0 enable root-dir"
  echo
  echo "Enables repo authoritative mode. Finds PHP or Hack source code"
  echo "under \"root-dir\" and computes an optimized repo where that code"
  echo "(and only that code) is available. If repo mode is already"
  echo "enabled, the repo will be recomputed and replaced."
  echo
  echo
  echo "$0 disable"
  echo
  echo "Disables repo authoritative mode. HHVM will return to its default"
  echo "configuration of reading and executing code directly from disk."
  exit 1
}

set_hhbc() {
  HHBC=`grep hhvm.repo.central.path "$INI" | sed 's/[^=]*=\s*\(.*\)/\1/'`
  if [ "x$HHBC" = "x" ]; then
    mkdir -p /var/cache/hhvm
    USER=`stat -c "%U" "/var/run/hhvm"`
    chown -R "$USER" "/var/cache/hhvm"
    echo "hhvm.repo.central.path = /var/cache/hhvm/hhvm.hhbc" >> "$INI"
    HHBC="/var/cache/hhvm/hhvm.hhbc"
  fi
}

repo_enable() {
  FILE_LIST=`mktemp`
  find "$1" -type f > "$FILE_LIST"

  OUT_DIR=`dirname "$HHBC"`
  hhvm --hphp --target hhbc --output-dir "$OUT_DIR" --input-list "$FILE_LIST" -l3 -v AllVolatile=true

  OUT_DIR_USER=`stat -c "%U" "$OUT_DIR"`
  HHBC_USER=`stat -c "%U" "$HHBC"`
  if [ "$OUT_DIR_USER" != "$HHBC_USER" ]; then
    chown "$OUT_DIR_USER" "$HHBC"
  fi

  echo "hhvm.repo.authoritative = true" >> "$INI"
}

repo_disable() {
  rm -f "$HHBC"
  sed -i '/hhvm.repo.authoritative/d' "$INI"
}

case "$1" in
  enable)
    if [ "$#" -ne 2 ] || ! [ -d "$2" ]; then
      echo "Invalid root-dir"
      usage
    fi
    service hhvm stop
    set_hhbc
    repo_disable
    repo_enable "$2"
    service hhvm start
    ;;
  disable)
    service hhvm stop
    set_hhbc
    repo_disable
    service hhvm start
    ;;
  *)
    usage
    ;;
esac

echo
echo "Success!"