# A Document to add in a VSMIndex
class Document

	# Document title
	var title: String

	# Document URI
	var uri: String

	# Count of all terms found in the document
	#
	# Used to compute the document `terms_frequency`.
	var terms_count: Vector

	# Frequency of each term found in the document
	#
	# Used to match the document against the `VSMIndex::inverse_doc_frequency`.
	var terms_frequency: Vector is lazy do
		var all_terms = 0.0
		for t, c in terms_count do all_terms += c

		var vector = new Vector
		for t, c in terms_count do
			vector[t] = c / all_terms
		end
		return vector
	end

	# Term frequency–Inverse document frequency for each term
	#
	# A high weight in tf–idf is reached by a high term frequency
	# (in the given document) and a low document frequency of the term in the
	# whole collection of documents
	var tfidf: Vector = terms_count is lazy

	redef fun to_s do return "{title}"
end