#!/bin/bash
#
# $Id$
#
set -e

declare -i cntr=0
declare -a spaceSTR="                                                                   "

#----------------------------#
generate_dependency_tree() { #
#----------------------------#
: <<inline_doc
    function:   Create a dependency tree for the TARGET
    input vars: none
    externals:  vars: TARGET
                      PKGXML
		      DEP_LEVEL
                func: do_dependencies
    modifies:   vars: PKGXML
                      BLFS_XML
    returns:    nothing
    output:     files: $TARGET.dep
                       $TARGET-index.xml.tmp
                       depure.txt
    on error:   nothing
    on success: nothing
inline_doc

  local ENTRY_START
  local ENTRY_END

  #---------------------
  # Create the working directory and cd into it
  if [[ -d $TARGET ]] ; then
    echo -e "\tERROR: Looks like $TARGET has been already processed."
    echo -e "\tPlease delete or rename the $TARGET directory.\n"
    exit 1
  else
    mkdir $TARGET && cd $TARGET
  fi

  #---------------------
  # XML file of the target package
  PKGXML=`grep "^$TARGET[[:space:]]" ../packages | cut -f2`

  #---------------------
  # The BLFS sources directory.
  # Note: for book.xsl this value must be set via a sed in ./blfs.
  # For consistency, we should to do the same here.
  BLFS_XML=`echo $PKGXML | sed -e 's,/.*,,'`

  if [[ ! -d ../$BLFS_XML ]] ; then
    echo -e "\tThe BLFS book sources directory is missing.\n"
    echo -e "\tExecution aborted.\n"
    cd .. && rmdir $TARGET
    exit 1
  fi

  #---------------------
  # XInclude stuff
  ENTRY_START="<xi:include xmlns:xi=\"http://www.w3.org/2003/XInclude\" href=\"../"
  ENTRY_END="\"/>"

  echo -e "\tGenerating $TARGET dependencies tree ..."

  mkdir dependencies

  #---------------------
  # Create target package dependencies list
  case $TARGET in
    # Skip the creation when all dependencies are circular.
    alsa-lib | cracklib | libexif | unixodbc ) ;;

    # Meta-packages at target level
    alsa )
      cp ../libs/alsa.dep dependencies/
      ;;
    gnome-core )
      cp ../libs/gnome-core.dep dependencies/
      ;;
    gnome-full )
      cp ../libs/gnome-{core,full}.dep dependencies/
      ;;
    kde-core )
      cp ../libs/kde-core.dep dependencies/
      ;;
    kde-full )
      cp ../libs/kde-{core,full}.dep dependencies/
      ;;
    kde-koffice )
      cp ../libs/kde-{core,full,koffice}.dep dependencies/
      ;;
    xorg7 )
      cp ../libs/xorg7.dep dependencies/
      ;;
    * ) # Default
      xsltproc --stringparam dependencies $DEP_LEVEL \
               -o dependencies/$TARGET.dep \
               ../libs/dependencies.xsl ../$PKGXML
      ;;
  esac

  #---------------------
  # Start with a clean $TARGET-index.xml.tmp file
  > $TARGET-index.xml.tmp

  #---------------------
  # Write the XInclude
  case $TARGET in
    # If there is no usefull XML page, skip it.
    alsa | gnome-core | gnome-full | kde-core | kde-full | kde-koffice ) ;;
    * )
      echo -e "    $ENTRY_START$PKGXML$ENTRY_END" >> $TARGET-index.xml.tmp
      ;;
  esac

  #---------------------
  # If have dependencies, write its XInclude and find sub-dependencies
  if [[ -f dependencies/$TARGET.dep ]]; then
    mkdir xincludes && do_dependencies $TARGET
  fi

  echo -e "\n\t... done"
}



#-----------------------#
do_dependencies()  {    #  Loop to find sub-dependencies  :::WARNING::: THIS IS A RECURVISE FUNCTION
#-----------------------#
: <<inline_doc
    function:   Loop through all the packages and create a sub-dependency tree
    input vars: $1, package name
    externals:  vars:  $DEP_LEVEL
                       $TARGET
                       $PRINT_SERVER
                       $KBR5
                       $GHOSTSCRIPT
                       $MAILSERVER
                file:  depure.txt
                       $TARGET-index.xml.tmp
                       $PKG.dep
                       $PKG.inc
    modifies:   files
    returns:    nothing
    output:     file:  $PKG-xinc.tmp
                       depure.txt
                       $TARGET-index.xml.tmp
    on error:   exit
    on success:
inline_doc

  set -e
  local PKG=$1
  local saveIFS=$IFS
  local DEP_LV=$DEP_LEVEL
  local line line2 DEP

  #------------------
  #  If a premade xinclude file exists, use it. If not, create one
  if [[ -f xincludes/$PKG.xinc ]] ; then
    IFS=$'\x0A'
    for line in `cat xincludes/$PKG.xinc` ; do
      IFS=$saveIFS
      # Remove the Xinclude entry if found. We want the most newer one.
      # Using double quotes to let bash expand variables.
      # Remove also the empty line created. Can not be done in one step
      # due that d requires the pattner between /, but we have a lot of /
      # inside the pattner.
      sed -e "s,^[[:space:]]*$line,," -e '/./!d' -i $TARGET-index.xml.tmp
      # Write the XInclude
      echo -e "$line" >> $TARGET-index.xml.tmp
    done
    return
  fi

  #------------------
  # Start with a clean $PKG.xinc.tmp file
  > xincludes/$PKG.xinc.tmp
  for DEP in `cat dependencies/$PKG.dep`; do
    # Special packages (a lot of hacks)
    case $DEP in

      db ) continue ;; # The proper version of DB is installed in LFS

        # Don't have their own XML file
      hal-requirements | hal-runtime-dependencies ) continue ;;
      perl-* | tk-perl )         DEP=perl-modules ;;

        # Orphan links (proper link must be created when generating the book)
      arts )                     DEP=aRts ;;
      kde )                      DEP=kde-core ;;

       # Dummy gnome-core pages
      GNOME-desktop-file-utils ) DEP=desktop-file-utils ;;
      GNOME-shared-mime-info )   DEP=shared-mime-info ;;

        # Set values for alternative packages
        # X is a meta-package, thus handled in another way.
      LPRng | cups )             DEP=$PRINT_SERVER ;;
      mitkrb | heimdal )         DEP=$KBR5 ;;
      gs | espgs )               DEP=$GHOSTSCRIPT ;;
      server-mail )              DEP=$MAIL_SERVER ;;
    esac

    #------------------
    # Prevent circular dependencies
    # If all dependencies are circular, the creation of the *.dep file
    # must be skipped, not placed here, to avoid that the script will bomb
    # due empty *.xinc files
    case $DEP in
      jadetex | perl-* | lynx | Links | w3m )
        # Optional dependencies are runtime only
        [[ "$PKG" = "docbook-utils" ]] && continue
        ;;
      libxslt )
        # libxml2-->libxslt-->libxml2
        [[ "$PKG" = "libxml2" ]] && continue
        ;;
      openldap | postgresql | $KBR5 )
        # cyrus-sasl-->several-->cyrus-sasl
        [[ "$PKG" = "cyrus-sasl" ]] && continue
        ;;
      espgs )
        # sendmail-->espgs-->cups-->php-->sendmail
        [[ "$PKG" = "$MAIL_SERVER" ]] && continue
        ;;
      aRts )
        # esound-->aRts-->esound
        [[ "$PKG" = "esound" ]] && continue
        ;;
      gimp | sane )
        # imagemagick-->{sane}-->gimp-->imagemagick
        [[ "$PKG" = "imagemagick" ]] && continue
        ;;
      ffmpeg )
        # alsa-plugins-->ffmpeg-->several-->alsa-plugins
        [[ "$PKG" = "alsa-plugins" ]] && continue
        ;;
      akode )
        # Both are in the same page
        [[ "$PKG" = "kdemultimedia" ]] && continue
        ;;
    esac

    #------------------
    # XML file of dependency package
    DEP_XML=`grep "^$DEP[[:space:]]" ../packages | cut -f2`
    case $DEP in
      x-window-system | alsa ) ;; # No page for that (proper link must be created when generating the book)
      xorg7 ) ;; # This page will be dump in the xorg7.xinc file
      gnome-core | kde-core | kde-full ) ;; # Invented packages
      * )
        # Remove the Xinclude entry if found
        sed -e "s,^[[:space:]]*$ENTRY_START$DEP_XML$ENTRY_END,," \
            -e '/./!d' -i xincludes/$PKG.xinc.tmp
        # Write the XInclude
        echo -e "    $ENTRY_START$DEP_XML$ENTRY_END" >> xincludes/$PKG.xinc.tmp
        ;;
    esac

    #------------------
    # If not already created, create its dependencies list
    if [[ ! -f dependencies/$DEP.dep ]] ; then
      case $DEP in
        # Skip the creation when all dependencies are circular.
        alsa-lib | cracklib | libexif | unixodbc ) ;;
        # Meta-packages at dependency level
        alsa )
          cp ../libs/alsa.dep dependencies/
          ;;
        kde-core )
          cp ../libs/kde-core.dep dependencies/
          ;;
        x-window-system ) # X11 alternatives
          echo -e "x-config\nx-setup\n$X11" > dependencies/x-window-system.dep
          ;;
        xorg7 ) # At dependencies level, remove x-config and x-setup
          cp ../libs/xorg7.dep dependencies/
          sed -i '/x-config/d;/x-setup/d' dependencies/xorg7.dep
          ;;
        * ) xsltproc --stringparam dependencies $DEP_LV \
               -o dependencies/$DEP.dep ../libs/dependencies.xsl ../$DEP_XML
          ;;
      esac
    fi

    #------------------
    # If needed, process its dependencies
    if [[ -f dependencies/$DEP.dep ]] ; then
      # If a premade xinclude file esist, include it
      if [[ -f xincludes/$DEP.xinc ]] ; then
        IFS=$'\x0A'
        for line2 in `cat xincludes/$DEP.xinc` ; do
          IFS=$saveIFS
          # Remove the Xinclude entry if found
          sed -e "s,^[[:space:]]*$line2,," -e '/./!d' -i xincludes/$PKG.xinc.tmp
          # Write the XInclude
          echo -e "$line2" >> xincludes/$PKG.xinc.tmp
        done
      #------------------
      # Create the xinclude file
      else
	#
	# >>>>>> THIS IS A RECURSIVE FUNCTION CALL.. BEWARE OF GREMLINS. <<<<<<
	#
	# If the recursion depth is not too great this is an acceptable methodology for a script language
	# However, uncontrolled recursion will cause a seg-fault due to stack issues with local variables.
	#
        set +e
         [[ "${VERBOSITY}" > 0 ]] && echo -ne "\ncall: $((++cntr))${spaceSTR:0:$cntr}${RED}$DEP${OFF}"
            do_dependencies $DEP
         [[ "${VERBOSITY}" > 0 ]] && echo -ne "\n ret: $cntr${spaceSTR:0:$((cntr--))}${GREEN}$DEP${OFF}  Using $DEP Xinc to solve $PKG"
        set -e

        # Include it when done
        IFS=$'\x0A'
        for line2 in `cat xincludes/$DEP.xinc` ; do
          IFS=$saveIFS
          # Remove the Xinclude entry if found
          sed -e "s,^[[:space:]]*$line2,," -e '/./!d' -i xincludes/$PKG.xinc.tmp
          # Write the XInclude
          echo -e "$line2" >> xincludes/$PKG.xinc.tmp
        done
      fi
    fi
  done

  #------------------
  if [[ "$PKG" = "xorg7" ]] ; then
    # Add their XInclude
    PKG_XML=${BLFS_XML}/x/installing/xorg7.xml
    echo -e "    $ENTRY_START$PKG_XML$ENTRY_END" >> xincludes/$PKG.xinc.tmp
  fi

  #------------------
  mv xincludes/$PKG.xinc.tmp xincludes/$PKG.xinc
  IFS=$'\x0A'
  for line in `cat xincludes/$PKG.xinc` ; do
    IFS=$saveIFS
    # Remove the Xinclude entry if found.
    sed -e "s,^[[:space:]]*$line,," -e '/./!d' -i $TARGET-index.xml.tmp
    # Write the XInclude
    echo -e "$line" >> $TARGET-index.xml.tmp
  done
}