#!/bin/sh
#
# This is an example of using HGEDITOR to automate the signing of
# commits and so on.

T1=""; T2=""
cleanup_exit() {
    rm -f "$T1" "$T2"
    exit $1
}

# If you want to pass your favourite editor some other parameters
# only for Mercurial, modify this:
case "${EDITOR:=vi}" in
    emacs)
        EDITOR="$EDITOR -nw"
        ;;
    gvim|vim)
        EDITOR="$EDITOR -f -o"
        ;;
esac

if grep -q "^HG: merge resolve" "$1" ; then
    # we don't sign merges
    exec $EDITOR "$1"
else
    # Remove temporary files even if we get interrupted
    trap "cleanup_exit 255" TERM KILL INT QUIT ABRT
    T1=`mktemp`; T2=`mktemp`

    # Add manifest hash in order to sign whole repository state.
    # Remove HG: prefix, as we want that to be stored.
    grep '^HG: manifest hash' "$1" | cut -b 5- >> "$T1"
    # Add all other state information
    grep -v '^HG: manifest hash' "$1" >> "$T1"
    (
        cd "`hg root`"
        grep '^HG: changed' "$1" | cut -b 13- | while read changed; do
            hg diff "$changed" >> "$T2"
        done
    )

    CHECKSUM=`md5sum "$T1"`
    $EDITOR "$T1" "$T2" || cleanup_exit $?
    echo "$CHECKSUM" | md5sum -c 2>/dev/null && cleanup_exit 13
    {
        head -n 1 "$T1"
        echo
        grep -v "^HG:" "$T1" | gpg -t -a -u "${HGUSER}" --clearsign
    } > "$T2" && mv "$T2" "$1"
    cleanup_exit $?
fi