#============================================================================
# Helper rules
#============================================================================

CP ?= "cp" ;
MV ?= "mv" ;

##  Wildcard [ dir : ] patterns
##    Create a list of files in a directory which match the pattern. You can
##    optionally specify a subdirectory. The files will be returned with
##    stripped pathnames. The difference from GLOB is that this rule respects
##    subdirectories which may have been entered with the SubDir rule.
rule Wildcard
{
  local files dir sdir wildcards ;
  
  # Is a directory given?
  if $(>) {
    dir = $(<)/ ;
    sdir = $(<) ;
    wildcards = $(>) ;
  } else {
    dir = "" ;
    sdir = "" ;
    wildcards = $(<) ;
  }

  files = [ GLOB [ ConcatDirs $(SUBDIR) $(dir) ] : $(wildcards) ] ;

  return $(files:BSR=$(sdir)) ;
}

##  Prefix list : prefix
##    Adds a prefix to a all elements in list.
rule Prefix
{
  return $(>)$(<) ;
}

if $(JAMVERSION) >= 2.5
{

##  IsElem element : list
##    Returns "true" if the elemnt is in the list. Otherwise nothing is
##    returned.
rule IsElem
{
  local i ;

  for i in $(>)
  {
    if $(i) = $(<)
    {
      return "true" ;
    }
  }

  return ;
}

}
else
{

# jam<2.4's return statement doesn't exit the function
rule IsElem
{
  local i result ;

  for i in $(>)
  {
    if $(i) = $(<)
    {
      result = "true" ;
      $(>) = ;
    }
  }

  return $(result) ;
}

}

##  Filter list : filter
##    Returns the list without the words contained in filter.
rule Filter
{
  local i result ;

  for i in $(<)
  {
    if ! [ IsElem $(i) : $(>) ]
    {
      result += $(i) ;
    }
  }

  return $(result) ;
}

##  RemoveDups list
##    Removes duplicates in the list (this function tries to preserve the list
##    order)
rule RemoveDups
{
  local i result ;

  for i in $(<)
  {
    if ! [ IsElem $(i) : $(result) ]
    {
      result += $(i) ;
    }  
  }

  return $(result) ;
} 

rule Reverse
{
  local result ;
  
  for i in $(<)
  {
    result = $(i) $(result) ;
  }
  return $(result) ;
}

##  GetVar argument
##    Simply returns the value of the variable with name argument.
##    This is useful to query on target variables:
##       bla = [ on TARGET GetVar CFlags ] ;
rule GetVar
{
  return $($(<)) ;
}

##  ConcatDirs dirs
##    Concatenates a set of directories. This is a substitute for FDirName in
##    Jambase. It works also correctly for several rooted paths, where FDirName
##    fails.
##    The advantage over $(dir1)/$(dir2) is that this also works correctly if
##    $(dir1) or $(dir2) is not set.
rule ConcatDirs
{
  local i ;
  local result = $(<[1]) ;
  if ! $(result) { $result = "" ; }
  local dir1 dir2 ;

  for i in $(<[2-])
  {
    # eleminate multiple slashes because jam is somewhat buggy here
    dir1 = [ MATCH (.*[^/]?) : $(result) ] ;
    dir2 = [ MATCH ([^/].*) : $(i) ] ;
    if ! $(dir1) { dir1 = "" ; }
    if $(dir1) != "" { dir1 = $(dir1)/ ; }
    if ! $(dir2) { dir2 = "" ; }
    result = $(dir1)$(dir2) ;
  }

  return $(result) ;
}

##  Copy target : source
##    Copy source file to target.
actions Copy
{
  $(CP) "$(>)" "$(<)"
}

actions ignore Move
{
  $(MV) $(>) $(<)
}