#!/bin/bash

assert_is_app() {
  local check_link=yes
  local version=

  while getopts "Cv:" opt
  do
    case $opt in
      C)
        check_link=no
        ;;
      v)
        version=$OPTARG
        ;;
    esac
  done

  if [ ! -d .app ]
  then
    echo "This is not an app, missing directory: '.app'"  >&2
    exit 1
  fi

  if [[ $check_link == yes ]]
  then
    if [ ! -e current ]
    then
      fatal "Missing 'current' link." >&2
    fi
  fi

  if [[ $version != "" ]]
  then
    if [[ ! -d versions/$version ]]
    then
      fatal "No such version: $version"
    fi
  fi
}

debug() {
  [[ $echo_debug == no ]] || echo "D: $usage_app: $@" 2>&1
}

info() {
  echo "I: $usage_app: $@" 2>&1
}

fatal() {
  echo "$usage_app: fatal: $@" 2>&1
  exit 1
}

list_apps() {
  local filter_name=$1; shift
  local filter_instnace=$1; shift
  local vars="$@"

  sort $apps/.app/var/list | while read line
  do
    echo $line | (IFS=:; while read name instance version junk
    do
      if [ -n "$filter_name" -a "$filter_name" != "$name" ]
      then
        continue
      fi

      if [ -n "$filter_instance" -a "$filter_instance" != "$instance" ]
      then
        continue
      fi

      local line=""
      IFS=" "; for var in $vars
      do
        case $var in
          name) x=$name;;
          instance) x=$instance;;
          version) x=$version;;
          current_version) x=`find_current_version $name $instance`;;
          *) x="";;
        esac

        if [ -z "$line" ]
        then
          line="$line$x"
        else
          line="$line:$x"
        fi
      done
      echo $line
    done)
  done
}

find_current_version() {
  local name=$1
  local instance=$2

  if [ ! -L $apps/$name/$instance/current ]
  then
    return 0
  fi

  (
    cd $apps/$name/$instance
    ls -l current | sed -n "s,.* current -> versions/\(.*\)/root,\1,p"
  )
}

find_versions() {
  local name="$1"
  local instance="$2"

  if [ ! -d $apps/$name/$instance/versions ]
  then
    return 0
  fi

  (
    cd $apps/$name/$instance/versions
    ls -1d *
  )
}

grep_path() {
  local regex="$1"; shift
  local path="$1"; shift

  find `echo $path | tr : " "` -type f -executable 2>/dev/null | (egrep "$regex" || exit 0)
#  IFS=:
#  for x in $path
#  do
#    ls $x/* 2>/dev/null | while read f
#    do
#      if [[ $f =~ $regex ]]
#      then
#        echo $f
#      fi
#    done
#  done
}

# TODO: set ulimit
# TODO: set umask
# TODO: change group newgrp/sg
# usage: run_app [-v version] [bin to execute]
run_app() {
  version=
  while getopts "v:" opt
  do
    case $opt in
      v)
        version=$OPTARG
		shift 2
		OPTIND=1
        ;;
    esac
  done

  local bin=$1; shift
  local e=`app-cat-conf -f .app/config -n "env\..*" | cut -f 2- -d .`

  (
	if [[ $version == "" ]]
	then
	  assert_is_app
	  cd current
	else
	  assert_is_app -v "$version"
	  cd "versions/$version"
	fi

    # This magically get the expansion of $u correct.
    IFS="
"

    # Set a default PATH which can be overridden by the application's settings
    set +e
    env -i \
      PATH=/bin:/usr/bin \
      $e \
      PWD="$PWD" \
      APPSH_HOME=$APPSH_HOME \
      $bin "$@"
    local ret=$?
    set +x
    set -e

    exit $ret
  )
}

#####################################################################
# Common init

# Add the app-* apps to PATH. They're added last to allow the user to
# overload their implementations.
PATH=$PATH:$APPSH_HOME/bin:$APPSH_HOME/libexec

# Save for later
usage_app=${0##*/}
echo_debug=${echo_debug-no}