#!/bin/bash

log()
{
	echo "$myname: $*" >&2
}

fatal()
{
	echo "$myname: Fatal: $*" >&2
	exit 1
}

usage()
{
	cat <<-EOT

	   usage $myname [-e sed-extract-command] [-m module] file.py ...

	EOT
	[ "$1" ] && exit $1
}

module_path()
{
	if [ "$module" = "." ]; then
		echo .$1
	elif [ "$module" ]; then
		echo $module.$1
	else
		echo $1
	fi
}

cmd_create_init()
{
	__add_seen() {
		local type="$1"
		[[ -n "${seen[$type]+x}" ]] && fatal "Duplicate symbol: $type"
		seen["$type"]=1
	}

	local import_submodules=0
	local files="$*"
	local del="-------------------------- generated by $myname"
	echo "# >> $del >>"
	echo "# ruff: noqa: E501"
	echo "from pkgutil import extend_path"
	echo ""
	echo "__path__ = extend_path(__path__, __name__)"
	echo
	local f
	local -A seen=()
	local dst_type
	for f in $files; do
		test -d $f && continue
		local base=${f##*/}
		base=${base%.py}
		if [ "$sed_extract_cmd" ]; then
			local src_type types=$(sed "$sed_extract_cmd" $f)
			for src_type in $types; do
				if [ -z "$sed_symbol_filter_cmd" ]; then
					dst_type="$src_type"
				else
					dst_type=$(echo $base $src_type | sed "$sed_symbol_filter_cmd")
				fi
				[ "$sed_symbol_filter_cmd" ] && dst_type=$(echo $base $src_type | sed "$sed_symbol_filter_cmd")
				echo "from `module_path $base` import $src_type as $dst_type"
				__add_seen $dst_type
			done
		fi
	done
	if [ "$import_submodules" = 1 ]; then
		for f in $files; do
			[ -f $f/__init__.py ] || continue
			echo "import `module_path $f` as $f"
			__add_seen $f
		done
	fi

	echo
	echo "__all__ = ["
	for dst_type in ${!seen[@]}; do
		echo "    \"$dst_type\","
	done
	echo "]"

	echo "# << $del <<"
}

# --------------------- here we go

myname=`basename $0`

eval set -- `getopt -l 'symbol-filter:' -o 'he:m:' "$@"`
while [ "$1" != -- ]; do
case $1 in
	-e)
		sed_extract_cmd="$2"
		shift
		;;
	--symbol-filter)
		sed_symbol_filter_cmd="$2"
		shift
		;;
	-m)
		module=$2
		shift
		;;
	-h)
		usage 0;;
	*)
		echo unknown argument $1
		usage 1;;
esac
shift
done
shift

cmd=cmd_${1//-/_}
shift

eval $cmd $*