# set python command if 'py' not installed
builtin which py > /dev/null || alias py='python3'

# Find python file
alias pyfind='find . -name "*.py"'

# Remove python compiled byte-code and mypy/pytest cache in either the current
# directory or in a list of specified directories (including sub directories).
function pyclean() {
  find "${@:-.}" -type f -name "*.py[co]" -delete
  find "${@:-.}" -type d -name "__pycache__" -delete
  find "${@:-.}" -depth -type d -name ".mypy_cache" -exec rm -r "{}" +
  find "${@:-.}" -depth -type d -name ".pytest_cache" -exec rm -r "{}" +
}

# Add the user installed site-packages paths to PYTHONPATH, only if the
#   directory exists. Also preserve the current PYTHONPATH value.
# Feel free to autorun this when .zshrc loads.
function pyuserpaths() {
  setopt localoptions extendedglob

  # Check for a non-standard install directory.
  local user_base="${PYTHONUSERBASE:-"${HOME}/.local"}"

  local python version site_pkgs
  for python in python2 python3; do
    # Check if command exists
    (( ${+commands[$python]} )) || continue

    # Get minor release version.
    # The patch version is variable length, truncate it.
    version=${(M)${"$($python -V 2>&1)":7}#[^.]##.[^.]##}

    # Add version specific path, if:
    # - it exists in the filesystem
    # - it isn't in $PYTHONPATH already.
    site_pkgs="${user_base}/lib/python${version}/site-packages"
    [[ -d "$site_pkgs" && ! "$PYTHONPATH" =~ (^|:)"$site_pkgs"(:|$) ]] || continue
    export PYTHONPATH="${site_pkgs}${PYTHONPATH+":${PYTHONPATH}"}"
  done
}

# Grep among .py files
alias pygrep='grep -nr --include="*.py"'

# Run proper IPython regarding current virtualenv (if any)
alias ipython='python3 -c "import IPython, sys; sys.exit(IPython.start_ipython())"'

# Share local directory as a HTTP server
alias pyserver="python3 -m http.server"


## venv utilities

# Activate a the python virtual environment specified.
# If none specified, use 'venv'.
function vrun() {
  local name="${1:-venv}"
  local venvpath="${name:P}"

  if [[ ! -d "$venvpath" ]]; then
    echo >&2 "Error: no such venv in current directory: $name"
    return 1
  fi

  if [[ ! -f "${venvpath}/bin/activate" ]]; then
    echo >&2 "Error: '${name}' is not a proper virtual environment"
    return 1
  fi

  . "${venvpath}/bin/activate" || return $?
  echo "Activated virtual environment ${name}"
}

# Create a new virtual environment, with default name 'venv'.
function mkv() {
  local name="${1:-venv}"
  local venvpath="${name:P}"

  python3 -m venv "${name}" || return
  echo >&2 "Created venv in '${venvpath}'"
  vrun "${name}"
}

# Virtual environment is assumed to be named "venv".
# Set VENV_NAME to another name if you use a different name, maybe ".venv".
# To disable, set DISABLE_AUTO_VRUN to anything. Unset to re-enable.
auto_vrun() {
    [ $DISABLE_AUTO_VRUN ] && return 0
    local venvpath=${VENV_NAME:-'venv'}
    if [ -e "${venvpath}/bin/activate" ]; then
        source "${venvpath}/bin/activate" > /dev/null 2>&1
    else
        [ -n "$(command -v deactivate)" ] && deactivate > /dev/null 2>&1
    fi
}
add-zsh-hook chpwd auto_vrun
auto_vrun