# A VSMIndex to index files
class FileIndex
	super StringIndex

	# Index a file from its `path`.
	#
	# Return the created document or null if `path` is not accepted by `accept_file`.
	#
	# See `index_document`.
	fun index_file(path: String, auto_update: nullable Bool): nullable DOC do
		if not accept_file(path) then return null
		var vector = parse_file(path)
		var doc = new Document(path, path, vector)
		index_document(doc, auto_update)
		return doc
	end

	# Index multiple files
	#
	# The recursive method `index_dir` will be called for each directory found
	# in `paths`.
	#
	# See `index_file`
	fun index_files(paths: Collection[String], auto_update: nullable Bool) do
		for path in paths do
			if path.to_path.is_dir then
				index_dir(path, false)
			else
				index_file(path, false)
			end
		end
		if auto_update != null and auto_update then update_index
	end

	# Index all files in `dir` recursively
	#
	# See `index_file`.
	fun index_dir(dir: String, auto_update: nullable Bool) do
		if not dir.to_path.is_dir then return
		for file in dir.files do
			var path = dir / file
			if path.to_path.is_dir then
				index_dir(path, false)
			else
				index_file(path, false)
			end
		end
		if auto_update != null and auto_update then update_index
	end

	# Is `path` accepted depending on `whitelist_exts` and `blacklist_exts`?
	fun accept_file(path: String): Bool do
		var ext = path.file_extension
		if ext != null then
			ext = ext.to_lower
			if blacklist_exts.has(ext) then return false
			if whitelist_exts.not_empty and not whitelist_exts.has(ext) then return false
		end
		return whitelist_exts.is_empty
	end

	# Parse the `file` content as a Vector
	#
	# See `parse_string`.
	fun parse_file(file: String): Vector do
		return parse_string(file.to_path.read_all)
	end

	# File extensions white list
	#
	# If not empty, only files with these extensions will be indexed.
	#
	# If an extension is in both `whitelist_exts` and `blacklist_exts`, the
	# blacklist will prevail and the file will be ignored.
	var whitelist_exts = new Array[String] is writable

	# File extensions black list
	#
	# Files with these extensions will not be indexed.
	var blacklist_exts = new Array[String] is writable
end