#!/bin/bash
#
# **inc/python** - Python-related functions
#
# Support for pip/setuptools interfaces and virtual environments
#
# External functions used:
# - GetOSVersion
# - is_fedora
# - is_suse
# - safe_chown

# Save trace setting
INC_PY_TRACE=$(set +o | grep xtrace)
set +o xtrace


# Global Config Variables

# PROJECT_VENV contains the name of the virtual environment for each
# project.  A null value installs to the system Python directories.
declare -A PROJECT_VENV


# Python Functions
# ================

# Get the path to the pip command.
# get_pip_command
function get_pip_command {
    local version="$1"
    # NOTE(dhellmann): I don't know if we actually get a pip3.4-python
    # under any circumstances.
    which pip${version} || which pip${version}-python

    if [ $? -ne 0 ]; then
        die $LINENO "Unable to find pip${version}; cannot continue"
    fi
}

# Get the path to the directory where python executables are installed.
# get_python_exec_prefix
function get_python_exec_prefix {
    local xtrace
    xtrace=$(set +o | grep xtrace)
    set +o xtrace
    if [[ -z "$os_PACKAGE" ]]; then
        GetOSVersion
    fi
    $xtrace

    if is_fedora || is_suse; then
        echo "/usr/bin"
    else
        echo "/usr/local/bin"
    fi
}

# Wrapper for ``pip install`` that only installs versions of libraries
# from the global-requirements specification.
#
# Uses globals ``REQUIREMENTS_DIR``
#
# pip_install_gr packagename
function pip_install_gr {
    local name=$1
    local clean_name
    clean_name=$(get_from_global_requirements $name)
    pip_install $clean_name
}

# Determine the python versions supported by a package
function get_python_versions_for_package {
    local name=$1
    cd $name && python setup.py --classifiers \
        | grep 'Language' | cut -f5 -d: | grep '\.' | tr '\n' ' '
}

# Wrapper for ``pip install`` to set cache and proxy environment variables
# Uses globals ``OFFLINE``, ``PIP_VIRTUAL_ENV``,
# ``PIP_UPGRADE``, ``TRACK_DEPENDS``, ``*_proxy``,
# pip_install package [package ...]
function pip_install {
    local xtrace result
    xtrace=$(set +o | grep xtrace)
    set +o xtrace
    local upgrade=""
    local offline=${OFFLINE:-False}
    if [[ "$offline" == "True" || -z "$@" ]]; then
        $xtrace
        return
    fi

    time_start "pip_install"

    PIP_UPGRADE=$(trueorfalse False PIP_UPGRADE)
    if [[ "$PIP_UPGRADE" = "True" ]] ; then
        upgrade="--upgrade"
    fi

    if [[ -z "$os_PACKAGE" ]]; then
        GetOSVersion
    fi
    if [[ $TRACK_DEPENDS = True && ! "$@" =~ virtualenv ]]; then
        # TRACK_DEPENDS=True installation creates a circular dependency when
        # we attempt to install virtualenv into a virtualenv, so we must global
        # that installation.
        source $DEST/.venv/bin/activate
        local cmd_pip=$DEST/.venv/bin/pip
        local sudo_pip="env"
    else
        if [[ -n ${PIP_VIRTUAL_ENV:=} && -d ${PIP_VIRTUAL_ENV} ]]; then
            local cmd_pip=$PIP_VIRTUAL_ENV/bin/pip
            local sudo_pip="env"
        else
            local cmd_pip
            cmd_pip=$(get_pip_command $PYTHON2_VERSION)
            local sudo_pip="sudo -H"
            if python3_enabled; then
                # Look at the package classifiers to find the python
                # versions supported, and if we find the version of
                # python3 we've been told to use, use that instead of the
                # default pip
                local package_dir=${!#}
                local python_versions
                if [[ -d "$package_dir" ]]; then
                    python_versions=$(get_python_versions_for_package $package_dir)
                    if [[ $python_versions =~ $PYTHON3_VERSION ]]; then
                        cmd_pip=$(get_pip_command $PYTHON3_VERSION)
                    fi
                fi
            fi
        fi
    fi

    cmd_pip="$cmd_pip install"
    # Always apply constraints
    cmd_pip="$cmd_pip -c $REQUIREMENTS_DIR/upper-constraints.txt"

    # FIXME(dhellmann): Need to force multiple versions of pip for
    # packages like setuptools?
    local pip_version
    pip_version=$(python -c "import pip; \
                        print(pip.__version__.strip('.')[0])")
    if (( pip_version<6 )); then
        die $LINENO "Currently installed pip version ${pip_version} does not" \
            "meet minimum requirements (>=6)."
    fi

    $xtrace
    $sudo_pip \
        http_proxy="${http_proxy:-}" \
        https_proxy="${https_proxy:-}" \
        no_proxy="${no_proxy:-}" \
        PIP_FIND_LINKS=$PIP_FIND_LINKS \
        $cmd_pip $upgrade \
        $@
    result=$?

    # Also install test requirements
    local test_req="${!#}/test-requirements.txt"
    if [[ $result == 0 ]] && [[ -e "$test_req" ]]; then
        echo "Installing test-requirements for $test_req"
        $sudo_pip \
            http_proxy=${http_proxy:-} \
            https_proxy=${https_proxy:-} \
            no_proxy=${no_proxy:-} \
            PIP_FIND_LINKS=$PIP_FIND_LINKS \
            $cmd_pip $upgrade \
            -r $test_req
        result=$?
    fi

    time_stop "pip_install"
    return $result
}

# get version of a package from global requirements file
# get_from_global_requirements <package>
function get_from_global_requirements {
    local package=$1
    local required_pkg
    required_pkg=$(grep -i -h ^${package} $REQUIREMENTS_DIR/global-requirements.txt | cut -d\# -f1)
    if [[ $required_pkg == ""  ]]; then
        die $LINENO "Can't find package $package in requirements"
    fi
    echo $required_pkg
}

# should we use this library from their git repo, or should we let it
# get pulled in via pip dependencies.
function use_library_from_git {
    local name=$1
    local enabled=1
    [[ ,${LIBS_FROM_GIT}, =~ ,${name}, ]] && enabled=0
    return $enabled
}

# determine if a package was installed from git
function lib_installed_from_git {
    local name=$1
    pip freeze 2>/dev/null | grep -- "$name" | grep -q -- '-e git'
}

# check that everything that's in LIBS_FROM_GIT was actually installed
# correctly, this helps double check issues with library fat fingering.
function check_libs_from_git {
    local lib=""
    local not_installed=""
    for lib in $(echo ${LIBS_FROM_GIT} | tr "," " "); do
        if ! lib_installed_from_git "$lib"; then
            not_installed+=" $lib"
        fi
    done
    # if anything is not installed, say what it is.
    if [[ -n "$not_installed" ]]; then
        die $LINENO "The following LIBS_FROM_GIT were not installed correct: $not_installed"
    fi
}

# setup a library by name. If we are trying to use the library from
# git, we'll do a git based install, otherwise we'll punt and the
# library should be installed by a requirements pull from another
# project.
function setup_lib {
    local name=$1
    local dir=${GITDIR[$name]}
    setup_install $dir
}

# setup a library by name in editable mode. If we are trying to use
# the library from git, we'll do a git based install, otherwise we'll
# punt and the library should be installed by a requirements pull from
# another project.
#
# use this for non namespaced libraries
function setup_dev_lib {
    local name=$1
    local dir=${GITDIR[$name]}
    setup_develop $dir
}

# this should be used if you want to install globally, all libraries should
# use this, especially *oslo* ones
function setup_install {
    local project_dir=$1
    setup_package_with_constraints_edit $project_dir
}

# this should be used for projects which run services, like all services
function setup_develop {
    local project_dir=$1
    setup_package_with_constraints_edit $project_dir -e
}

# determine if a project as specified by directory is in
# projects.txt. This will not be an exact match because we throw away
# the namespacing when we clone, but it should be good enough in all
# practical ways.
function is_in_projects_txt {
    local project_dir=$1
    local project_name
    project_name=$(basename $project_dir)
    grep -q "/$project_name\$" $REQUIREMENTS_DIR/projects.txt
}

# ``pip install -e`` the package, which processes the dependencies
# using pip before running `setup.py develop`
#
# Updates the constraints from REQUIREMENTS_DIR to reflect the
# future installed state of this package. This ensures when we
# install this package we get the from source version.
#
# Uses globals ``REQUIREMENTS_DIR``
# setup_develop directory
function setup_package_with_constraints_edit {
    local project_dir=$1
    local flags=$2

    if [ -n "$REQUIREMENTS_DIR" ]; then
        # Constrain this package to this project directory from here on out.
        local name
        name=$(awk '/^name.*=/ {print $3}' $project_dir/setup.cfg)
        $REQUIREMENTS_DIR/.venv/bin/edit-constraints \
            $REQUIREMENTS_DIR/upper-constraints.txt -- $name \
            "$flags file://$project_dir#egg=$name"
    fi

    setup_package $project_dir $flags

}

# ``pip install -e`` the package, which processes the dependencies
# using pip before running `setup.py develop`
# Uses globals ``STACK_USER``
# setup_develop_no_requirements_update directory
function setup_package {
    local project_dir=$1
    local flags=$2

    pip_install $flags $project_dir
    # ensure that further actions can do things like setup.py sdist
    if [[ "$flags" == "-e" ]]; then
        safe_chown -R $STACK_USER $1/*.egg-info
    fi
}

# Report whether python 3 should be used
function python3_enabled {
    if [[ $USE_PYTHON3 == "True" ]]; then
        return 0
    else
        return 1
    fi
}

# Install python3 packages
function install_python3 {
    if is_ubuntu; then
        apt_get install python3.4 python3.4-dev
    fi
}

# Restore xtrace
$INC_PY_TRACE

# Local variables:
# mode: shell-script
# End: