#!/bin/sh

# https://gist.github.com/smoser/2d4100a6a5d230ca937f

CR='

'

error() { echo "$@" 1>&2; }

fail() { [ $# -eq 0 ] || error "$@"; exit 1; }

get_env_dirs() {

    # read 'tox --showconfig'. return list of

    #  envname:dir

    local key="" equal="" val="" curenv="" out=""

    while read key equal val; do

        case "$key" in

           "[testenv:"*)

                curenv=${key#*:};

                curenv=${curenv%%"]"*};

                continue;;

        esac

        if [ "${key#*=}" != "$key" ]; then

            # older tox shows key=value or key=   value

            # newer tox shows: key =    value

            key=${key%%=*}

            val=${equal}

        fi

        [ "$key" = "envdir" ] || continue

        out="${out:+${out}${CR}}${curenv}:$val"

    done

    echo "$out"

}

load_config() {

    local tox_ini="$1" out="" envs=""

    if [ "$tox_ini" = "${CACHED_ENVS_INI}" ]; then

        _RET="$CACHED_ENVS"

        return

    fi

    out=$(tox -c "$tox_ini" --showconfig) || return 1

    envs=$(echo "$out" | get_env_dirs) || return 1

    CACHED_ENVS="$envs"

    CACHED_ENVS_INI="$tox_ini"

    _RET="$envs"

}

list_environments() {

    local tox_ini="$1" prefix="  " out="" envs="" oifs="$IFS"

    load_config "$tox_ini" || return 1

    envs="${_RET}"

    IFS="$CR"

    for d in ${envs}; do

        env=${d%%:*}

        dir=${d#*:}

        [ -f "$dir/bin/activate" ] && s="*" || s=""

        echo "${prefix}$env$s";

    done

    IFS="$oifs"

}

get_command() {

    local tox_ini="$1" env="$2" out=""

    shift 2

    out=$(

        sed -e ':x; /\\$/ { N; s/\\\n[ ]*//; tx };' "${tox_ini}" |

        gawk '

        $1 ~ /^\[testenv.*\]/ {

            name=$1;

            sub("\\[", "", name); sub(".*:", "", name);

            sub("].*", "", name);

            curenv=name; };

        $1 == "basepython" && (name == "testenv" || name == n) { python=$3 }

        $1 == "commands" && (name == "testenv" || name == n) {

            sub("commands = ", ""); cmd = $0; };

        END {

            sub("{envpython}", python, cmd);

            sub("{toxinidir}", toxinidir, cmd);

            if (inargs == "") replacement = "\\1"

            else replacement = inargs

            cmd = gensub(/{posargs:?([^}]*)}/, replacement, "global", cmd)

            print(cmd);

            }' n="$env" toxinidir="$(dirname $tox_ini)" inargs="$*")

    if [ -z "$out" ]; then

        error "Failed to find command for $env in $tox_ini"

        return 1

    fi

    echo "$out"

}

get_env_dir() {

    local tox_ini="$1" env="$2" oifs="$IFS" t="" d="" envs=""

    if [ "${TOX_VENV_SHORTCUT:-1}" != "0" ]; then

        local stox_d="${tox_ini%/*}/.tox/${env}"

        if [ -e "${stox_d}/bin/activate" ]; then

            _RET="${stox_d}"

            return

        fi

    fi

    load_config "$tox_ini" && envs="$_RET" || return 1

    IFS="$CR"

    for t in $envs; do

        [ "$env" = "${t%%:*}" ] && d="${t#*:}" && break

    done

    IFS=${oifs}

    [ -n "$d" ] || return 1

    _RET="$d"

}

Usage() {

    local tox_ini="$1"

    cat <

Usage: ${0##*/} [--no-create] tox-environment [command [args]]

   run command with provided arguments in the provided tox environment

   command defaults to 'cmd' (see below).

   run with '--list' to show available environments

   if 'command' above is literal 'cmd' or '-', then the 'command' will

   be read from tox.ini.  This allows you to do:

      tox-venv py27 - tests/some/sub/dir

   and have the 'command' read correctly and have that execute:

      python -m pytest tests/some/sub/dir

EOF

    if [ -f "$tox_ini" ]; then

        local oini=${tox_ini}

        [ "${tox_ini}" -ef "$PWD/tox.ini" ] && oini="./tox.ini"

        echo

        echo "environments in $oini"

        list_environments "$tox_ini"

    fi

}

if [ -f tox.ini ]; then

    tox_ini="$PWD/tox.ini"

else

    tox_ini="${0%/*}/../tox.ini"

fi

[ $# -eq 0 ] && { Usage "$tox_ini" 1>&2; exit 1; }

[ "$1" = "-h" -o "$1" = "--help" ] && { Usage "$tox_ini"; exit 0; }

[ -f "$tox_ini" ] || fail "$tox_ini: did not find tox.ini"

if [ "$1" = "-l" -o "$1" = "--list" ]; then

    list_environments "$tox_ini"

    exit

fi

nocreate="false"

if [ "$1" = "--no-create" ]; then

    nocreate="true"

    shift

fi

env="$1"

shift

[ "$1" = "--" ] && shift

get_env_dir "$tox_ini" "$env" && activate="$_RET/bin/activate" || activate=""

if [ -z "$activate" -o ! -f "$activate" ]; then

    if $nocreate; then

        fail "tox env '$env' did not exist, and no-create specified"

    elif [ -n "$activate" ]; then

        error "attempting to create $env:"

        error "    tox -c $tox_ini --recreate --notest -e $env"

        tox -c "$tox_ini" --recreate --notest -e "$env" ||

            fail "failed creation of env $env"

    else

        error "$env: not a valid tox environment?"

        error "found tox_ini=$tox_ini"

        error "try one of:"

        list_environments "$tox_ini" 1>&2

        fail

    fi

fi

. "$activate"

[ $# -eq 0 ] && set -- cmd

if [ "$1" = "cmd" -o "$1" = "-" ]; then

   shift

   out=$(get_command "$tox_ini" "$env" "$@") || exit

   eval set -- "$out"

fi

echo "inside tox:$env running: $*" 1>&2

debian_chroot="tox:$env" exec "$@"

# vi: ts=4 expandtab