#!/bin/bash

shellfu import jat
shellfu import pretty

#
# upgrade path utilities
#

preupg_upath__find() {
    #
    # Find module according to criteria
    #
    # Look into installed upgrade path modules and print all ids or ids
    # selected by a condition.
    #
    #     preupg_upath__find [-FIELD RE].. [-print FIELD[:FIELD]..]
    #
    # Where FIELD is one of supported fields and RE is basic regular expression
    # to be matched against that field.  List of all modules found on the
    # system is collected; then each module is checked against all conditions.
    # If it matches all conditions, its short id is printed, unless `-print`
    # is provided, in which case the argument that follows is interpreted as
    # colon-separated list of fields that should be printed.  Multiple fields
    # on output are separated by colon.
    #
    # List of supported conditions:
    #
    #  *  `id` - short id,
    #  *  `xid` - long "xccdf_preupg_rule_" id,
    #  *  `relpath` - relative path from upgrade path root
    #  *  `path` - absolute path
    #  *  `name` - only the name part (directory name)
    #  *  `group` - "group" part of the id,
    #  *  `upath` - upgrade path names.
    #
    local Conds=()
    local cond_name
    local cond_arg
    local dir
    local usage="usage: preupg_upath__find [-FIELD RE].."
    while true; do case $1 in
        -*)
            cond_name=${1:1}
            cond_arg=$2
            shift 2 || {
                jat__log_error "$usage"
                return 2
            }
            Conds+=("$cond_name:$cond_arg")
            ;;
        "")
            break
            ;;
        *)
            shift 2 || {
                jat__log_error "$usage"
                return 2
            }
    esac done
    __preupg_upath__find_dirs \
      | while read -r dir;
        do
            __preupg_upath__find_ckconds "$dir"
        done
}


#          #                                     your brain upgrade path #
# INTERNAL # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #
#          #                                    does not cross this line #

__preupg_upath__find_dirs() {
    #
    # List all paths to module directories
    #
    local path
    rpm -qal "preupgrade-assistant-el6toel*" \
      | grep -v '/usr/share/preupgrade/[[:alnum:]]\+/common' \
      | while read -r path;
        do
            test -d "$path"             || continue
            test -f "$path/group.xml"   || continue
            test -f "$path/check"       || continue
            echo "$path"
        done
}

__preupg_upath__find_ckconds() {
    #
    # Check all condition pairs
    #
    local mpath=$1
    local cond
    local cond_name
    local cond_arg
    local ok=true
    local fields=upath:id
    local field
    for cond in "${Conds[@]}";
    do
        cond_name=${cond%%:*}
        cond_arg=${cond#*:}
        case $cond_name in
            id|xid|group|name|path|relpath|upath)
                __preupg_upath__find_getfield "$cond_name" "$mpath" \
                  | grep -q "$cond_arg" \
                 || ok=false
                ;;
            print)
                fields=$cond_arg
                ;;
            *)
                jat__log_error "unknown condition: $cond"
                return 2
                ;;
        esac
    done
    $ok || return 1
    __preupg_upath__find_fmt "$fields" "$mpath"
}

__preupg_upath__find_fmt() {
    #
    # Format meta data of module $2 according to field list $1
    #
    local fields=$1
    local mpath=$2
    local field
    for field in ${fields//:/ };
    do
        __preupg_upath__find_getfield "$field" "$mpath"
    done \
      | paste -sd:
}

__preupg_upath__find_getfield() {
    #
    # Get field $1 from module at path $1
    #
    local field=$1
    local mpath=$2
    local getfield=__preupg_upath__find_getfield
    case $field in
        id)
            $getfield relpath "$mpath" \
              | sed 's:/:_:g'
            ;;
        xid)
            echo -n "xccdf_preupg_rule_"
            echo -n "$($getfield id "$mpath")"
            echo -n "_check"
            ;;
        name)
            echo "${mpath##*/}"
            ;;
        group)
            $getfield relpath "$mpath" \
              | sed 's:/[^/]*$::; s:/:_:g'
            ;;
        upath)
            cut -d/ -f5 <<<"${mpath}" \
              | __preupg_upath__find_upath_old2new
            ;;
        relpath)
            cut -d/ -f6- <<<"${mpath}"
            ;;
        path)
            echo "$mpath"
            ;;
        *)
            jat__log_error "unknown field: $field"
            return 2
            ;;
    esac
}

__preupg_upath__find_upath_old2new() {
    #
    # Convert from old style upgrade path name to new
    #
    # Usage: echo el6toel7 | __preupg_upath__find_upath_old2new
    #
    local oupath
    while read -r oupath;
    do
        case $oupath in
            RHEL?_?) echo "el${oupath:4:1}toel${oupath:6}" ;;
            *) jat__log_error "unknown old-style upgrade path name: $oupath" ;;
        esac
    done
}

#shellfu module-version=__MKIT_PROJ_VERSION__