#!/bin/bash
#
# texinfo_updateSectionMenu.sh -- This function updates the section's
# menu definition file of a chapter.  If this function is called with
# the '--delete-entry' string as first argument, the menu line related
# to the entry being processed is removed. Otherwise, if this function
# is called with the '--add-entry' string as first argument, the menu
# line related to the entry being processed is added to menu's bottom.
# If no argument is passed to this function, the '--add-entry' action
# is assumed.
#
# Copyright (C) 2009-2013 The CentOS Project
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or (at
# your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
# ----------------------------------------------------------------------
# $Id$
# ----------------------------------------------------------------------

function texinfo_updateSectionMenu {

    # Specify which action to do with documentation entry inside the
    # chapter menu.
    local ACTION="$1"

    # Define section order. Through this property you can customize
    # the section order inside the manual.  Possible arguments to this
    # option are `ordered', `reversed', `created'.  From these three
    # values `created' is used by default (i.e., new menu entries are
    # added to menu's bottom as last entry.).  Notice that, once
    # you've sorted the menu using `ordered' or `reversed' values, it
    # is hard to sort the list back to former creation orders. Go
    # sorted or not sorted at all.
    local MANUAL_SECTION_ORDER=$(cli_getConfigValue "${MANUAL_CONFIG_FILE}" "main" "manual_section_order")
    if [[ ! $MANUAL_SECTION_ORDER =~ '^(created|ordered|reversed)$' ]];then
        MANUAL_SECTION_ORDER='created'
    fi

    # Build node information used inside chapter menu.
    local MENUNODE=$(texinfo_getEntryNode "$MANUAL_ENTRY")

    # Define menu entry using texinfo style and node information as
    # reference.
    local MENULINE="* ${MENUNODE}::" 

    # Retrieve list of menu entries from chapter menu and exclude
    # `@menu', `@end menu' and empty lines from output.
    local MENU=$(cat  ${MENUFILE} \
        | egrep -v '^[[:space:]]*$' | egrep -v '^@(end )?menu')

    # Re-defined chapter menu entries based on action provided to this
    # function as first positional parameter.
    case $ACTION in

        --delete-entry )
            # Remove menu entry from chapter menu.
            MENU="$(echo "$MENU" | egrep -v "$MENULINE")"
            ;;

        --add-entry | * )
            # Add menu entry to chapter menu list as last entry.
            MENU="$(echo "$MENU" | egrep -v "$MENULINE" )
                ${MENULINE}"
            ;;

    esac

    # Remove opening spaces/tabs and empty lines from final menu
    # entries.
    MENU=$(echo "$MENU" | sed -r 's!^[[:space:]]+!!g' \
        | egrep -v '^[[:space:]]*$')

    # Sort menu entries based on section order property.
    case $MANUAL_SECTION_ORDER in

        'ordered' )
            MENU="$(echo "$MENU" | sort )"
            ;;

        'reversed' )
            MENU="$(echo "$MENU" | sort -r )"
            ;;

    esac

    # Rebuild list of chapter menu entries including '@menu' and '@end
    # menu' lines back into chapter menu.
    MENU="@menu
    $MENU
    @end menu"

    # Remove opening spaces/tabs and empty lines from final menu
    # structure.
    MENU=$(echo "$MENU" | sed -r 's!^[[:space:]]+!!g' \
        | egrep -v '^[[:space:]]*$')

    # Dump chapter menu entries back into chapter's menu definition
    # file.
    echo "$MENU" > ${MENUFILE}

}