#!/bin/bash

# metascript to include
#
# usual way if no parameters used by outer script :
#
# source $(dirname "$0")/metascript.sh
#
# defaultmetainit $@
#

metascript_included=yes

# assume all tools are in lib/
toolsdir=$(dirname $(readlink -f $0))/lib
# all tools resources are relative to this directory

# project directory
# relative
# toolsparentdir=$(realpath --relative-to "$(pwd)" $(readlink -f $0))/
# absolute
toolsparentdir=$(realpath $(readlink -f $0))/

if [[ -z $log_functions ]]
then
    log_functions=$toolsdir/log_functions.sh
    [[ -f $log_functions ]] || { echo "[FATAL] Missing $log_functions" >&2 ; exit 1 ;}
    source $log_functions
fi

metascript_usage()
{
    cat <<EOF >&2
metascript commands :

help|usage             help or usage of this {$0} tool
dryrun|show|showdoc    display what should/will be done

defersource=           script file defining defer() non sandard function
defer=                 defer function to use, default is showdoc
toolsresourcesdir=     where to pick resource
                       default to parent of script $toolsresourcesdir
                       mostly used with dryrun
apply                  default : will actual do work without defer
EOF
}

usage()
{
    echo "[WARNING} no specific usage function for {$0}, to improve by developer" >&2
    echo >&2
    metascript_usage
}

showinfo()
{
    echo $@
}

showdoc()
{
    if [[ $1 =~ ^tools/ ]]
    then
        # assumes it handles ENV_METASCRIPT_DEFER
        $@
    else
        echo '```'
        autoquoteargs $@
        echo
        echo '```'
    fi
}

redirectto()
{
    tofile=$1
    if [[ -n $defer ]]
    then
        echo "Copy to $tofile"
        echo '```'
        cat
        echo '```'
    else
        cat > $tofile
    fi
}

execredirectfrom()
{
    tofile=$1
    shift
    if [[ -n $defer ]]
    then
        echo '```'
        autoquoteargs $@
        echo ' < '"$tofile"
        echo '```'
    else
        $@ < $tofile
    fi
}

execredirectto()
{
    tofile=$1
    shift
    if [[ -n $defer ]]
    then
        echo '```'
        autoquoteargs $@
        echo ' > '"$tofile"
        echo '```'
    else
        $@ > $tofile
    fi
}

pipeto()
{
    if [[ -n $defer ]]
    then
        echo '```'
        echo -n 'cat << EOF| '
        autoquoteargs $@
        echo
        cat
        echo "EOF"
        echo '```'
    else
        cat | $@
    fi
}


query_ext()
{
    local prompt="$1"
    local var=$2

    if [[ -n $defer ]]
    then
        # uppercase it
        eval $var=${var^^}
        $defer query $prompt "$(eval echo \$$var)"
    else
        echo -ne $prompt
        read $var
    fi
}

# two arguments first prompt, second name of var
query_password()
{
    local prompt="$1"
    local var=$2

    if [[ -n $defer ]]
    then
        # uppercase it
        eval $var=${var^^}
        $defer query_password "\"$prompt\"" "$(eval echo \$$var)"
    else
        read -sp "$prompt" $var
        echo
    fi
}

# echo yes if reply match  ^[Yy]([eE][sS]|)$ or no if does not match.
query_yesno()
{
    local prompt="$1"
    local yesno=no

    read -p "$prompt (Yes/No) " yesno

    if [[ $yesno =~ ^[Yy]([eE][sS]|)$ ]]
    then
        echo yes
    else
        echo no
    fi
}


# through hardcoded 'secret' variable
create_secret()
{
    # global secret
    # declare -g secret
    # export -n secret

    local -i length=$1

    [[ -z $length ]] && length = 32

    if (( length < 8 ))
    then
        log_warn "secret length $length < 8. very small"
    fi
    # secret=$(echo $RANDOM | md5sum | head -c $length)
    secret=$(tr -dc A-Za-z0-9 </dev/urandom | head -c $length)
}

check_missing_dest_dir()
{
    local dir=$1
    if [[ -n $defer  ]]
    then
        $defer "create $dir if it does not exist"
    else

        if [[ ! -d $dir ]]
        then
            echo "[ERROR] '$dir' does not exist please create it."
            exit 1
        fi
     fi
}

sed_substitute_expr()
{
    local from="$1"
    shift
    local to="$1"
    shift
    local s='/'
    if  [[ $from =~ [\\] ]]
    then
# escape char \ should be doubled
        from=${from//\\/\\\\}
    fi
    if [[ $from =~ $s ]]
    then
# echo "[ERROR] character $s is prohibited due to sed usage" >&2
        from=${from//$s/\\$s}
    fi
    if [[ $from =~ \[ ]]
    then
        from=${from//\[/\\\[}
    fi
    if [[ $from =~ \* ]]
    then
        from=${from//\*/\\\*}
    fi
    if [[ $from =~ ^(.*)\$$ ]]
    then
        from=${BASH_REMATCH[1]}'\$'
    fi
    if [[ $from =~ ^\^(.*)$ ]]
    then
        from='\^'${BASH_REMATCH[1]}
    fi

    if  [[ $to =~ [\\] ]]
    then
# escape char \ should be doubled
        to=${to//\\/\\\\}
    fi
    if  [[ $to =~ $s ]]
    then
# echo "[ERROR] character $s is prohibited due to sed usage" >&2
# echo "This is a limitation of metascript.sh script, replaced by \$s" >&2
        to=${to//$s/\\$s}
    fi
    if  [[ $to =~ [\&] ]]
    then
# echo "[ERROR] character & is prohibited due to sed usage" >&2
        to=${to//\&/\\\&}
    fi

    # replace it globaly
    echo "s$s$from$s$to${s}g"

}

sedreplacefromto()
{
    local from="$1"
    local to="$2"
    shift 2
    local sedexpr="$1"
    execredirectto $to sed "$sedexpr" $from
    shift
    while [[ $# > 0 ]]
    do
        sedexpr="$1"
        $defer sed -i "$sedexpr" $to
        shift
    done

}

replacefromto()
{
    local from="$1"
    local to="$2"
    shift 2
    if [[ -n $defer ]]
    then
        $defer "replace $@  from '$from' into '$to'"
    else
        local sedexpr=$(sed_substitute_expr "$1" "$2")
        execredirectto $to sed "$sedexpr" $from
        shift 2
        while [[ $# > 0 ]]
        do
            sedexpr=$(sed_substitute_expr "$1" "$2")
            $defer sed -i "$sedexpr" $to
            shift 2
        done
    fi

}

sedreplacein()
{
    local file=$1
    shift
    while [[ $# > 0 ]]
    do
        $defer sed -i "$1" $file
        shift
    done
}

replacein()
{
    local infile=$1
    shift
    if [[ -n $defer ]]
    then
        $defer "replace $@ into '$infile'"
    else
        while [[ $# > 0 ]]
        do
            sedexpr=$(sed_substitute_expr "$1" "$2")
            $defer sed -i "$sedexpr" $infile
            shift 2
        done
    fi
}

parsemetaarg()
{
    case $1 in
        apply)
            defer=
            ;;
        defersource=*)
            defersource=${1/defersource=/}
            ;;
        defer=*)
            defer=${1/defer=/}
            ;;
        dryrun|show|showdoc)
            defer=showdoc
            ;;
        help|usage)
            usage
            ;;
        toolsresourcesdir=*)
            toolsresourcesdir=${1/toolsresourcesdir=/}
            ;;
        scl_enable=*)
            scl_args=(scl enable ${1/scl_enable=/} --)
            ;;
        *)
            log_error "unrecognized argument '$1'"
            usage
            exit 1
            ;;
    esac
}

enforcearg()
{
    local var="$1"
    local default="$2"
    eval value='$'"$var"

    if [[ -z $value ]]
    then
        log_error "{0} expect '$var' to be set ex $var=$default"
        usage
        exit 1
    fi
}

enforcefile()
{
    file="$1"
    constraint="$2"

    if [[ ! -f "$file" ]]
    then
        if [[ $constraint = exists ]]
        then
            log_error "[ERROR] Missing expected $file"
            [[ -n $defer ]] || exit 1
        fi
    else
        if [[ $constraint = does_not_exists ]]
        then
            log_error "[ERROR] '$file' already exists. Move it away"
            [[ -n $defer ]] || exit 1
        fi
    fi
}

enforcedir()
{
    dir="$1"
    constraint="$2"

    if [[ $constraint = does_not_exist ]]
    then
        if [[ -e $dir ]]
        then
            log_error "'$dir' already exists. Move it away"
            [[ -n $defer ]] || exit 1
        fi
    fi

    if [[ $constraint = exists ]]
    then
        if [[ ! -d "$dir" ]]
        then
            if [[ -e "$dir" ]]
            then
                log_error "'$dir' already exists but is not a directory as expected"
                [[ -n $defer ]] || exit 1
            fi
            log_error "[ERROR] Missing expected directory '$dir'"
            [[ -n $defer ]] || exit 1
        fi

    fi

}

applymetaargs()
{
    if [[ -n $defer ]]
    then
        if [[ -n $defersource ]]
        then
            if [[ -f $defersource ]]
            then
                log_any "source $defersource"
                source $defersource
            else
                exit_fatal "defersource $defersource provided but not a file"
            fi
        fi
        # $showinfo "generated with $0 $allparms"
        export ENV_METASCRIPT_DEFER="$defer"
        export ENV_METASCRIPT_RESOURCESDIR="$toolsresourcesdir"
    fi
}

defaultmetainit()
{
    while [[ $# > 0 ]]
    do
        parsemetaarg "$1"
        shift
    done

    applymetaargs
}

read_organisation()
{
    organisation_file=$(find organisation -name '*.conf')
    if [[ -f $organisation_file ]]
    then
        while read line
        do
            case $line in
                name=*)
                    organisation_name=${line/name=/}
                    ;;
                domain=*)
                    organisation_domain=${line/domain=/}
                    ;;
                ldap_base=*)
                    organisation_ldap_base=${line/ldap_base=/}
                    ;;
                image_keyword=*)
                    organisation_image_keyword=${line/image_keyword=/}
                    ;;
                *)
                    log_warn "'$line' not recognized as an organisation parameter"
                    ;;
            esac
        done < $organisation_file
    fi
}

check_variable_match()
{
    local var="$1"
    local match="$2"
    local default="$3"
    local value=""

    eval value='$'"$var"

    if [[ -z "$value" ]]
    then
        echo "set $var to default value $default"
        eval "$var=$default"
        eval value='$'"$var"
    fi

    if [[ ! $value =~ $match ]]
    then
        log_error "$var $value should match $match"
        exit 1
    fi

}

check_variable_in()
{
    local var="$1"
    local default="$2"
    shift 2

    local value=""
    local values=$@

    eval value='$'"$var"

    if [[ -z "$value" ]]
    then
        echo "set $var to default value $default"
        eval "$var=$default"
        eval value='$'"$var"
    fi

    while [[ $# > 0 ]]
    do
        if [[ "$value" = "$1" ]]
        then
            return
        fi
        shift
    done

    log_error "'$var' should be within $values it is '$value'"
    exit 1
}

check_root()
{
    if [[ -n $defer ]]
    then
        $defer "{$0} script to run run as root or with sudo"
    else
        [[ $EUID -eq 0 ]] || {
            log_error "{$0}  You have to be root or use sudo to run this script"
            exit 1;
        }
    fi
}

get_timestamp_second()
{
    echo "$(date +"%Y%m%d%H%M%S")"
}

if [[ -z $ENV_METASCRIPT_RESOURCESDIR ]]
then
    toolsresourcesdir=$toolsparentdir
else
    toolsresourcesdir=$ENV_METASCRIPT_RESOURCESDIR
fi

# quick way to give scl patches to fill scl_arg array
if [[ -f $toolsparentdir/.scl_env ]]
then
    source $toolsparentdir/.scl_env
fi

# empty defer means doit
defer=$ENV_METASCRIPT_DEFER

showinfo=showinfo

allparms=$@

applymetaargs=applymetaargs