#!/bin/bash "Do not execute. Shebang line exists for syntax highlighting."


# A file containing simple functions used in determining version numbers of 
# installed programs, based on ctime.
#
# Author:: Dan
# Date::   10 June 2006

Import GoboLinux
Import File
Import String

# Gets the currently-installed version of the given program by reading the
# 'Current' link. If the Current link doesn't exist, or if the program isn't
# installed, this function returns no text and a nonzero result.
# Usage Example:
#     Current_Version Scripts
function Current_Version() {
   Parameters "$@" programName
   local basedir="$goboPrograms/$programName"
   Is_Directory "$basedir" || return 1
   Is_Link "$basedir/Current" || return 1
   basename "$(readlink -f "$basedir/Current")"
   return 0
}


# Determines the second-most-recently installed version of a program. By default
# it does this based on mtime, but you can pass atime or ctime as a second 
# argument to use that timestamp instead of the creation one. You can also pass
# GuessLatest as the second argument if you'd like to 
# Returns 1 if
# the program doesn't exist at all, or 2 if the Current version is installed.
# Usage Examples:
#     Previous_Version Scripts
#     Previous_Version Scripts ctime
#     Previous_Version Scripts GuessLatest
function Previous_Version() {
   local programName sortType version versions
   Parameters "$@" programName sortType
   [ "$sortType" ] || sortType=mtime
   
   useGuessLatest=''
   if [ "$sortType" = "GuessLatest" ]; then
      useGuessLatest='yes'
      sortType=mtime
   fi
   
   if [ "$sortType" = mtime ]; then
      sortType="--sort=time"
   else
      sortType="--time=$sortType"
   fi
   
   curVersion="`Current_Version $programName`" || return 1
   
   Quiet pushd "$goboPrograms/$programName"  
   versions=(
      `Chop "$( ls -1p $sortType --color=never | grep /$ )"       \
         | grep -vF Settings                                      \
         | grep -vF "$curVersion"`
   )
   Quiet popd


   [ "${versions}" ] || return 2   


   if [ "$useGuessLatest" ]; then
      GuessLatest -- "${versions[@]}"
   else
      echo "${versions[0]}"
   fi
}

# Gets all available versions of the given program by listing the
# contents in the program directory.
# Usage Example:
#     All_Versions Scripts
function All_Versions() {
   Parameters "$@" program
   program=$(GuessProgramCase "$program")
   if Is_Directory "$program" && [ -n "$(echo $program | grep \/)" ]
   then local basedir="$program"
   else local basedir="$goboPrograms/$program"
   fi
   Is_Directory "$basedir" || return 1
   versions=$(ls -I Settings -I Variable -I Current ${basedir})
   [ -z "${versions}" ] && return 1
   echo "${versions}"
   return 0
}