#!/usr/bin/env bash

shopt -s extglob

PYTHONS="/usr/bin/python /usr/bin/python2 `command -v python`"
CURL=`command -v curl`

trim()
{
    trimmed=$1
    trimmed="${trimmed#"${trimmed%%[![:space:]]*}"}"   # remove leading whitespace characters
    trimmed="${trimmed%"${trimmed##*[![:space:]]}"}"   # remove trailing whitespace characters
    echo $trimmed
}

usage()
{
    printf "
  Usage:

    ${0} [options]

    options:

      --python    : Python interpreter.

"
}

parse_arguments()
{
    for arg do
        val=`echo "$arg" | sed -e "s;--[^=]*=;;"`
        case "$arg" in
            --python=*) PYTHONS="$val $PYTHONS" ;;
            --help) usage ;;
            *) echo "Can't find the option. :$arg";;
        esac
    done
}

parse_arguments $@

if [[ ! -x $CURL ]] ; then
    echo "pythonbrew required curl. curl was not found in your path."
    exit
fi

for PYTHON in $PYTHONS ; do
    if [[ ! -x $PYTHON ]] ; then
        continue
    fi

    PYTHON_VERSION=`$PYTHON -V 2>&1`
    PYTHON_VERSION=${PYTHON_VERSION/"Python "/""}
    PYTHON_VERSION_S=`echo $PYTHON_VERSION | sed -e "s/\(^[[:digit:]]\{1,\}.[[:digit:]]\{1,\}\).*/\1/"`

    if [[ $PYTHON_VERSION_S = "2.4" ]] || [[ $PYTHON_VERSION_S = "2.5" ]] || [[ $PYTHON_VERSION_S = "2.6" ]] || [[ $PYTHON_VERSION_S = "2.7" ]] || [[ ${PYTHON_VERSION_S:0:1} = "3" ]] ; then
        PYTHON_FOUND='1'
        break
    fi
done
if [[ $PYTHON_FOUND != '1' ]] ; then
    echo "pythonbrew required Python (2.4, 2.5, 2.6 or 2.7)."
    #TODO Installing python.
    exit
fi

systemwide_install=0
if [[ -n "$PYTHONBREW_ROOT" ]] ; then
    ROOT="$PYTHONBREW_ROOT"
else
    if (( UID == 0 )) ; then
        systemwide_install=1
        ROOT="/usr/local/pythonbrew"
    else
        ROOT="$HOME/.pythonbrew"
    fi
fi
PATH_DISTS="$ROOT/dists"

STABLE_VERSION=`curl -skL https://github.com/utahta/pythonbrew/raw/master/stable-version.txt`
STABLE_VERSION=`trim $STABLE_VERSION`
if [[ -z "$STABLE_VERSION" ]] ; then
    echo 'Can not get stable-version of pythonbrew.'
    exit 1
fi
TEMP_FILE="pythonbrew-$STABLE_VERSION"
TEMP_TARBALL="$TEMP_FILE.tar.gz"
DOWNLOAD_URL="http://pypi.python.org/packages/source/p/pythonbrew/$TEMP_TARBALL"

mkdir -p "$PATH_DISTS"
rm -rf "$PATH_DISTS/$TEMP_TARBALL"
rm -rf "$PATH_DISTS/$TEMP_FILE"

echo "Downloading $DOWNLOAD_URL"
builtin cd $PATH_DISTS ; curl --progress-bar -kL $DOWNLOAD_URL -o "$TEMP_TARBALL"

echo "Extracting $PATH_DISTS/$TEMP_TARBALL"
builtin cd $PATH_DISTS ; tar zxf $TEMP_TARBALL

echo "Installing pythonbrew into $ROOT"
if (( systemwide_install == 1 )) ; then
    PYTHONBREW_ROOT="$ROOT" $PYTHON $PATH_DISTS/$TEMP_FILE/pythonbrew_install.py --systemwide
else
    $PYTHON $PATH_DISTS/$TEMP_FILE/pythonbrew_install.py
fi
if [[ $? == 1 ]] ; then
    echo "Failed to install pythonbrew."
    exit
fi