x

#!/bin/sh

# Modern Linux and macOS systems commonly only have a thing called `python3` and
# not `python`, while Windows commonly does not have `python3`, so we cannot
# directly use python in the x.py shebang and have it consistently work. Instead we
# have a shell script to look for a python to run x.py.

set -eu

# syntax check
sh -n "$0"

realpath() {
 local path="$1"
 if [ -L "$path" ]; then
 readlink -f "$path"
 elif [ -d "$path" ]; then
 # "cd" is not always silent (e.g. when CDPATH is set), so discard its output.
 (cd -P "$path" >/dev/null && pwd)
 else
 echo "$(realpath "$(dirname "$path")")/$(basename "$path")"
 fi
}

xpy=$(dirname "$(realpath "$0")")/x.py

# On Windows, `py -3` sometimes works. We need to try it first because `python3`
# sometimes tries to launch the app store on Windows.
# On MacOS, `py` tries to install "Developer command line tools". Try `python3` first.
# NOTE: running `bash -c ./x` from Windows doesn't set OSTYPE.
case ${OSTYPE:-} in
 cygwin*|msys*) SEARCH="py python3 python python2 uv";;
 *) SEARCH="python3 python py python2 uv";;
esac
for SEARCH_PYTHON in $SEARCH; do
 if python=$(command -v $SEARCH_PYTHON) && [ -x "$python" ]; then
 case $SEARCH_PYTHON in
 py)
 extra_arg="-3";;
 uv)
 extra_arg="run";;
 *)
 extra_arg="";;
 esac
 exec "$python" $extra_arg "$xpy" "$@"
 fi
done

python=$(bash -c "compgen -c python" | grep -E '^python[2-3](\.[0-9]+)?$' | head -n1)
if ! [ "$python" = "" ]; then
 exec "$python" "$xpy" "$@"
fi

echo "$0: error: did not find python installed" >&2
exit 1