#!/bin/sh
set -e

if [ -z "$CODENAME" ]; then
    echo "update_tasks: codename not specified" >&2
    exit 1
fi

if [ "$MIRROR"x = ""x ] ; then
    echo "update_tasks: mirror dir not specified" >&2
    exit 1
fi

if [ "$BDIR"x = ""x ] ; then
    echo "update_tasks: temp dir not specified" >&2
    exit 1
fi
TDIR=$BDIR/update_tasks
mkdir -p $TDIR

# Sort primary and secondary tasks and add language tasks for both
# Secondary tasks are indicated by a "-" suffix in the task.list file
# When adding language tasks, 'desktop' is sorted before '*-desktop'
expand_task_list () {
    outbase=$1
    tasklist=$2
    langlist=$3

    # Filter out comments, empty lines and secondary tasks
    task_primary="$(grep -Ev "^(#.*)?(.*-)?[[:space:]]*$" $tasklist)"
    # Select only secondary tasks
    task_secondary="$(grep -Ev "^(#.*)?[[:space:]]*$" $tasklist | \
        grep -E "(.*-)[[:space:]]*$" | sed "s/[[:space:]]\+-.*$//")"

    echo "# Primary main tasks" >$outbase.primary
    echo "$task_primary" >>$outbase.primary

    echo >>$outbase.primary
    echo "# Primary language tasks" >>$outbase.primary
    for task in "" $(echo "$task_primary" | grep "^desktop" || true) \
                $(echo "$task_primary" | grep -- "-desktop" || true); do
        for language in $(cat $langlist); do
            echo $language${task:+-$task}
        done
    done >>$outbase.primary

    rm -f $outbase.secondary
    if [ "$task_secondary" ]; then
        echo "# Secondary main tasks" >$outbase.secondary
        echo "$task_secondary" >>$outbase.secondary

        echo >>$outbase.secondary
        echo "# Secondary language tasks" >>$outbase.secondary
        for task in $(echo "$task_secondary" | grep "^desktop" || true) \
                    $(echo "$task_secondary" | grep -- "-desktop" || true); do
            for language in $(cat $langlist); do
                echo $language-$task
            done
        done >>$outbase.secondary
    fi
}

update_full_list () {
    file=$1
    tasklist=$2
    pkgfile=$3

    (grep -Ev "^(#.*)?[[:space:]]*$" $tasklist ; echo DONE ; cat $pkgfile) | mawk '
    /DONE/ {
        in_packages = 1
        next
    }
    /.*/ {
        if (!in_packages) {
            tasklist[$1] = num_tasks
            num_tasks++
        }
    }
    /^Package: / {
        if (in_packages) {
            pkgname = $2
            next
        }
    }
    /^Task: / {
        if (in_packages) {
            # Parse the Tasks: line, splitting into array "these"
            gsub("Task: ", "", $0)
            gsub(",", "", $0)
            split($0, these)

            # And see if we have any matches
            for (task in these) {
                for (taskname in tasklist) {
                    if (these[task] == taskname) {
                        printf("%d:%s\n", tasklist[taskname], pkgname)
                        next
                    }
                }
            }
        }
        next
    }' | sort -n | cut -d: -f2 >> $file
}

update_essential_list () {
    file=$1
    tasklist=$2
    tasksel=$3

    file=$tasksel/usr/share/tasksel/descs/debian-tasks.desc
    if [ ! -e $file ]; then
	    file=$tasksel/usr/share/tasksel/debian-tasks.desc
    fi

    (grep -Ev "^(#.*)?[[:space:]]*$" $tasklist ;
		echo DONE ;
		cat $file) | mawk '

    /DONE/ {
        in_tasks = 1
        next
    }
    /^ / {
        if (in_key) {
            printf("%d:%s\n", tasklist[cur_task], $1)
            next
        }
    }
    /.*/ {
        if (!in_tasks) {
            tasklist[$1] = num_tasks
            num_tasks++
        }
        if (in_key) {
            in_key = 0
        }
    }
    /^Task: / {
        if (in_tasks) {
            cur_task = $2
            next
        }
    }
    /^Key: / {
        if (in_tasks) {
            for (taskname in tasklist) {
                if (taskname == cur_task) {
                    in_key = 1
                }
            }
        }
        next
    }' | sort -s -n -k1 | cut -d: -f2 >> $file
}

# Look for the coreutils package (which should exist in all archs, and is
# a non -all package) to determine a valid arch for the rest of this
# script
arch=$($BASEDIR/tools/which_deb $MIRROR $CODENAME coreutils binary | sed -e "s/\.deb//" -e "s/.*_//")
# We need to gunzip a copy of the appropriate Packages.gz file(s)
TMP_PKG=$TDIR/Packages
zcat $MIRROR/dists/$CODENAME/main/binary-$arch/Packages.gz > $TMP_PKG
if [ -n "$LOCAL" ] ; then
    if [ -n "$LOCALDEBS" ] ; then
        zcat $LOCALDEBS/dists/$CODENAME/local/binary-$arch/Packages.gz >> $TMP_PKG
    else
        zcat $MIRROR/dists/$CODENAME/local/binary-$arch/Packages.gz >> $TMP_PKG
    fi
fi

# Now grab the appropriate tasksel package
TASKSEL_DEB=$MIRROR/`mawk '
    /^Package: tasksel-data$/ { found=1 }
    /^Filename:/              { if (found==1) { print $2; exit } }' $TMP_PKG`

# For testing purposes - set up FORCE_SID_TASKSEL to force us to use
# sid's tasksel data even if we're using stable/testing.
if [ "$FORCE_SID_TASKSEL"x = "1"x ] ; then
    echo "update_tasks: forcing use of the sid tasksel-data tasks"
    TASKSEL_DEB=$MIRROR/$($BASEDIR/tools/which_deb $MIRROR sid tasksel-data binary)
fi

dpkg -x $TASKSEL_DEB $TDIR/tasksel

[ -e task.languages ] || exit 1
grep -Ev "^(#.*)?[[:space:]]*$" task.languages > $TDIR/languages

for tlist in task.list.*; do
    variant=${tlist##*.}

    expand_task_list task.gen.$variant $tlist $TDIR/languages

    # Create (empty) output files
    : >task-essential-$variant
    : >task-full-$variant

    update_essential_list \
        task-essential-$variant \
        task.gen.$variant.primary \
        $TDIR/tasksel

    update_full_list \
        task-full-$variant \
        task.gen.$variant.primary \
        $TMP_PKG

    # Now add packages for secondary tasks; start with Key packages again
    if [ -e task.gen.$variant.secondary ]; then
        update_essential_list \
            task-full-$variant \
            task.gen.$variant.secondary \
            $TDIR/tasksel

        update_full_list \
            task-full-$variant \
            task.gen.$variant.secondary \
            $TMP_PKG
    fi
done

rm -rf $TDIR