#!/usr/bin/env bash
#
# Summary: Create an installable binary package from a Python version
#
# Usage: pyenv binary package <version>:<entry> --archive-base-url <url>
#
#   Installs <version> from source under the separate name <entry>, saves it as
#   a binary package, then emits a python-build definition for that package.
#   The archive, metadata and definition are written to the current directory
#   as <entry>.tar.gz, <entry>.meta and <entry>.
#
#   <version>             A version `pyenv install' knows how to build.
#   <entry>               The name to build under and to install the binary
#                         as, e.g. `3.13.14-debian-12'. Keeping it distinct
#                         from <version> lets the binary sit alongside a
#                         normal source install of the same version.
#   --archive-base-url <url>
#                         Where the archive will be hosted; the definition
#                         downloads it from <url>/<entry>.tar.gz.
#
set -e
[ -n "$PYENV_DEBUG" ] && set -x

# Provide pyenv completions
if [ "$1" = "--complete" ]; then
  echo --archive-base-url
  exec pyenv-install --list --bare
fi

spec=""
archive_base_url=""

while [ $# -gt 0 ]; do
  case "$1" in
  --archive-base-url )
    [ $# -ge 2 ] || { echo "pyenv-binary: --archive-base-url needs a value" >&2; exit 1; }
    archive_base_url="$2"; shift 2 ;;
  -* )
    echo "pyenv-binary: unknown option \`$1'" >&2; exit 1 ;;
  * )
    [ -z "$spec" ] || { echo "pyenv-binary: unexpected argument \`$1'" >&2; exit 1; }
    spec="$1"; shift ;;
  esac
done

if [ -z "$spec" ] || [ -z "$archive_base_url" ]; then
  pyenv-help --usage binary-package >&2
  exit 1
fi

case "$spec" in
*?:?* ) ;;
* )
  echo "pyenv-binary: expected <version>:<entry>, e.g. \`3.13.14:3.13.14-debian-12'" >&2
  exit 1
  ;;
esac
entry="${spec##*:}"

case "$entry" in
# `pyenv install' reads a trailing `:latest' as part of the version rather than
# as an alias, so nothing would end up installed under that name.
latest )
  echo "pyenv-binary: \`latest' cannot be used as an entry name" >&2
  exit 1
  ;;
# The entry becomes a directory name under versions/. `pyenv install' does not
# validate the alias, and `save' only checks once the build is done, so refuse
# a name that could point elsewhere before compiling anything.
*/* | .. | . )
  echo "pyenv-binary: invalid entry name \`${entry}'" >&2
  exit 1
  ;;
esac

os="$(uname -s)"

# `generate-installer' refuses a macOS archive, so the last step here cannot
# succeed on one. Give up before compiling rather than after it.
if [ "$os" = "Darwin" ]; then
  echo "pyenv-binary: macOS archives are not supported yet" >&2
  exit 1
fi

# `pyenv install' puts a `<version>:<alias>' build under versions/<alias>.
pyenv-install "$spec"
pyenv-binary-save "$entry" "$PWD" --name "$entry"

pyenv-binary-generate-installer "${entry}.meta" \
  --archive-url "${archive_base_url%/}/${entry}.tar.gz" -o "$entry"