#!@BASH_PATH@
#
# Copyright 2014-2024 the Pacemaker project contributors
#
# The version control history for this file may have further details.
#
# This source code is licensed under the GNU General Public License version 2
# or later (GPLv2+) WITHOUT ANY WARRANTY.
#

list_candidates() {
    ls -1 "${1}.rng" "${1}"-[0-9]*.rng 2>/dev/null
}

version_from_filename() {
    vff_filename="$1"

    case "$vff_filename" in
        *-*.rng)
            echo "$vff_filename" | sed -e 's/.*-\(.*\).rng/\1/'
            ;;
        *)
            # special case for bare ${base}.rng, no -0.1's around anyway
            echo 0.1
            ;;
    esac
}

filename_from_version() {
    ffv_version="$1"
    ffv_base="$2"

    if [ "$ffv_version" = "0.1" ]; then
        echo "${ffv_base}.rng"
    else
        echo "${ffv_base}-${ffv_version}.rng"
    fi
}

# Convert version string (e.g. 2.10) into integer (e.g. 2010) for comparisons
int_version() {
    echo "$1" | awk -F. '{ printf("%d%03d\n", $1,$2); }';
}

# Find the (sub-)schema that best matches a desired version.
#
# Version numbers are assumed to be in the format X.Y,
# where X and Y are integers, and Y is no more than 3 digits.
best_match() {
    # (Sub-)schema name (for example, "resources")
    local base="$1"

    # Desired version (for example, "1.0")
    local target="$2"

    # If not empty, append the best match as an XML externalRef to this file
    # (otherwise, just echo the best match).
    local destination="$3"

    # Arbitrary text to print before XML (generally spaces to indent)
    local prefix="$4"

    best="0.0"
    for rng in $(list_candidates "${base}"); do
        case ${rng} in
            ${base}-${target}.rng)
                # We found exactly what was requested
                best=${target}
                break
                ;;
            *)
                v=$(version_from_filename "${rng}")
	        if [ $(int_version "${v}") -gt $(int_version "${best}") ]; then
                    # This version beats the previous best match

                    if [ $(int_version "${v}") -lt $(int_version "${target}") ]; then
                        # This value is best only if it's still less than the target
                        best=${v}
                    fi
                fi
                ;;
        esac
    done

    if [ "$best" != "0.0" ]; then
        found=$(filename_from_version "$best" "$base")
        if [ -z "$destination" ]; then
            echo "$(basename $found)"
        else
            echo "${prefix}<externalRef href=\"$(basename $found)\"/>" >> "$destination"
        fi
        return 0
    fi
    return 1
}

version_diff() {
    # diff fails with ec=2 if no predecessor is found;
    # this uses '=' GNU extension to sed, if that's not available,
    # one can use: hline=`echo "$${p}" | grep -Fn "$${hunk}" | cut -d: -f1`;
    # XXX: use line information from hunk to avoid "not detected" for ambiguity
    for p in $*; do
        set $(echo "$p" | tr '-' ' ')
        echo "### *-$2.rng vs. predecessor"

        for v in *-"$2".rng; do
            echo "#### $v vs. predecessor"

            b=$(echo "$v" | cut -d- -f1)
            old=$(best_match "$b" "$1")
            p=$(diff -u "$old" "$v" 2>/dev/null)

            case $? in
                1)
                    echo "$p" | sed -n -e '/^@@ /!d;=;p' -e ':l;n;/^\([- ]\|+.*<[^ />]\+\([^/>]\+="ID\|>$$\)\)/bl;s/^[+ ]\(.*\)/\1/p' |
                    while read -r hline; do
                        if read -r h; then
                            read -r i
                        else
                            break
                        fi

                        iline=$(grep -Fn "$i" "$v" | cut -d: -f1)

                        if [ "$(echo "$iline" | wc -l)" = "1" ]; then
                            ctxt=$({ sed -n -e "1,$((iline - 1))p" "$v"
                                     echo "<inject id=\"GOAL\"/>$i"
                                     sed -n -e "$((iline + 1)),$ p" "$v"
                                   } | xsltproc --param skip 1 context-of.xsl -)
                        else
                            ctxt="(not detected)"
                        fi

                        echo "$p" | sed -n -e "$((hline - 2)),$hline!d" -e '/^\(+++\|---\)/p'
                        echo "$h context: $ctxt"
                        echo "$p" | sed -n -e "1,${hline}d" -e '/^\(---\|@@ \)/be;p;d;:e;n;be'
                    done

                    ;;

                2)
                    echo "##### $v has no predecessor"
                    ;;

            esac
        done
    done
}

build_api_rng() {
    local FILENAME="$1"
    local VERSION="$2"

    shift 2

    cat <<EOF >"$FILENAME"
<?xml version="1.0" encoding="UTF-8"?>
<grammar xmlns="http://relaxng.org/ns/structure/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
  <start>
    <element name="pacemaker-result">
      <attribute name="api-version"> <text /> </attribute>
      <attribute name="request"> <text /> </attribute>
      <optional>
        <choice>
EOF
    for RNG in "$@"; do
        best_match "api/$RNG" "$VERSION" "$FILENAME" "          "
    done
    cat <<EOF >>"$FILENAME"
        </choice>
      </optional>
EOF
    best_match api/status "$VERSION" "$FILENAME" "      "
    cat <<EOF >>"$FILENAME"
    </element>
  </start>
</grammar>
EOF
}

build_cib_rng() {
    local FILENAME="$1"
    local VERSION="$2"

    shift 2
    cat <<EOF >"$FILENAME"
<?xml version="1.0" encoding="UTF-8"?>
<grammar xmlns="http://relaxng.org/ns/structure/1.0" datatypeLibrary="http://www.w3.org/2001/XMLSchema-datatypes">
  <start>
    <element name="cib">
EOF
    best_match cib "$VERSION" "$FILENAME" "      "
    cat <<EOF >>"$FILENAME"
      <element name="configuration">
        <interleave>
EOF
    for RNG in "$@"; do
        best_match "$RNG" "$VERSION" "$FILENAME" "          "
    done
    cat <<EOF >>"$FILENAME"
        </interleave>
      </element>
      <optional>
        <element name="status">
EOF
    best_match status "$VERSION" "$FILENAME" "          "
    cat <<EOF >>"$FILENAME"
        </element>
      </optional>
    </element>
  </start>
</grammar>
EOF
}

# Allow building RNGs from a different directory
cd "$(dirname $0)"

case "$1" in
    match)
        # Using readlink allows building from a different directory
        best_match "$2" "$3" "$(readlink -f "$4")" "$5"
        ;;

    diff)
        shift
        version_diff "$@"
        ;;

    build_api_rng)
        build_api_rng "$2" "$3" "${@:4}"
        ;;

    build_cib_rng)
        build_cib_rng "$2" "$3" "${@:4}"
        ;;

    *)
        echo "Invalid command: $1"
        exit 1
        ;;
esac