#!/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
  mkdir $TARGET && cd $TARGET

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

  #---------------------
  # The BLFS sources directory.
  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 -en "\tGenerating $TARGET dependencies tree ..."

  #---------------------
  # Create target package dependencies list
  case $TARGET in
    # Meta-packages at target level
    # KDE and Gnome-{core,full} could be made via packages.sh, but not sure yet how.
    alsa ) # When target "alsa", use all alsa-* packages
      echo -e "alsa-oss\nalsa-firmware\nalsa-tools\nalsa-utils\n \
               alsa-plugins\nalsa-lib" > dependencies/$TARGET.dep
      ;;
    * ) # Default
      xsltproc --stringparam dependencies $DEP_LEVEL \
               -o dependencies/$TARGET.dep \
               ../dependencies.xsl ../$PKGXML
      ;;
  esac

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

  #---------------------
  # Write the XInclude
  echo -e "    $ENTRY_START$PKGXML$ENTRY_END" >> $TARGET-index.xml.tmp

  #------------------P---
  # Start with a clean depure.txt file
  > depure.txt

  #---------------------
  # If have dependencies, write its XInclude and find sub-dependencies
  if [[ -f dependencies/$TARGET.dep ]]; then
    echo -e "Start loop for PKG $TARGET\n" >> depure.txt
    mkdir xincludes && do_dependencies $TARGET
  fi

  echo "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
  echo -e "\tPKG is $PKG" >> depure.txt
  echo -e "\tDEP_LEVEL for $PKG is $DEP_LV\n" >> depure.txt

  #------------------
  #  If a premade xinclude file exists, use it. If not, create one
  if [[ -f xincludes/$PKG.xinc ]] ; then
    echo -e "\tReusing xinclude file for PKG $PKG" >> depure.txt
    IFS=$'\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 ) # The proper version of DB is installed in LFS
        continue ;;        
      hal-requirements ) # ID value don't have their own XML package file
        continue ;;
      perl-* | tk-perl )  DEP=perl-modules ;;

        # Orphan links (proper link must be created when generating the book)
      arts )              DEP=aRts ;; # That should be fixed in the BLFS book
        # 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=$GHOSTSCRIPT ;;
      MTA )               DEP=$MAIL_SERVER ;; # The BLFS book need be fixed yet for that
    esac

    #------------------
    echo -e "\tDEP for $PKG is $DEP" >> depure.txt
    case $DEP in
      # Circular dependencies at level 3
      cracklib | docbook-utils | libxml2 | cyrus-sasl | alsa-lib | \
      unixodbc | cups | libexif | esound | gimp )
        [[ "$DEP_LV" = "3" ]] && DEP_LV=2
        ;;
      * ) DEP_LV=$DEP_LEVEL ;;
    esac

    #------------------
    echo -e "\tDEP_LEVEL for $DEP is $DEP_LV" >> depure.txt
    # XML file of dependency package
    DEP_XML=`grep "^$DEP[[:space:]]" ../packages | cut -f2`
    echo -e "\t\tDEP_XML is $DEP_XML\n" >> depure.txt
    case $DEP in
      x-window-system ) ;; # No page for that (proper link must be created when generating the book)
      xorg7 ) ;; # This page will be dump in the xorg7.xinc file
      * )
        # Remove the Xinclude entry if found
        sed -e "s,^[[:space:]]*$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 $DEP in
        # Meta-packages at dependency level (ugly *.dep files, but work for now)
        alsa ) # When dependency "alsa", use all alsa-* packages
          echo -e "alsa-oss\nalsa-firmware\nalsa-tools\nalsa-utils\n \
                   alsa-plugins\nalsa-lib" > dependencies/$DEP.dep
          ;;
        x-window-system ) # X11 alternatives
          echo -e "x-config\nx-setup\n$X11" > dependencies/$DEP.dep
          ;;
        xorg7 ) # All Xorg7 packages except Xterm (circular dependency)
          echo -e "rman\nxorg7-driver\nxorg7-server\nluit\nxorg7-font\n \
                   xorg7-data\nxorg7-app\nxbitmaps\nmesalib\nlibdrm\n \
                   xorg7-lib\nxorg7-util\nxorg7-proto" > dependencies/$DEP.dep
          ;;
        * ) xsltproc --stringparam dependencies $DEP_LV \
               -o dependencies/$DEP.dep ../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
        echo -e "\tReusing xinclude file for PKG $DEP (to solve $PKG)\n" >> depure.txt
        IFS=$'\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
        echo -e "\nStart new loop for PKG $DEP (to solve $PKG)\n" >> depure.txt
	#
	# >>>>>> THIS IS A RECURSIVE FUNCTION CALL.. BEWARE OF GREMLINS. <<<<<<
	#
	# If the recursion depth is not too great this is an acceptable methodology for a script language
	# However, uncontrolled recursion will cause a seg-fault due to stack issues with local variables.
	# 
        set +e
         [[ "${VERBOSITY}" > 0 ]] && echo -ne "\nrecursive call: $((++cntr)) ${spaceSTR:0:$cntr} ${RED}$DEP${OFF}"
            do_dependencies $DEP
         [[ "${VERBOSITY}" > 0 ]] && echo -ne  "\nrecursive ret:  $cntr ${spaceSTR:0:$((cntr--))} ${GREEN}$DEP${OFF}\tUsing the new xinclude file for PKG $DEP (to solve $PKG)"
        set -e
	
        # Include it when done
        echo -e "\tUsing the new xinclude file for PKG $DEP (to solve $PKG)\n" >> depure.txt
        IFS=$'\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 [[ "$PKG" = "xorg7" ]] ; then
    # Add their XInclude
    PKG_XML=`grep "^$PKG[[:space:]]" ../packages | cut -f2`
    echo -e "    $ENTRY_START$PKG_XML$ENTRY_END" >> xincludes/$PKG.xinc.tmp
  fi

  #------------------
  mv xincludes/$PKG.xinc.tmp xincludes/$PKG.xinc
  echo -e "Using the new xinclude file for PKG $PKG" >> depure.txt
  IFS=$'\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

  echo -e "\nEnd loop for PKG $PKG\n" >> depure.txt
}