package wing_test

import (
	"os"
	"path/filepath"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/mathiasbq/hyperguild/ingestion/internal/wing"
)

func writePage(t *testing.T, dir, rel, body string) {
	t.Helper()
	full := filepath.Join(dir, rel)
	require.NoError(t, os.MkdirAll(filepath.Dir(full), 0o755))
	require.NoError(t, os.WriteFile(full, []byte(body), 0o644))
}

func scorerBrain(t *testing.T) string {
	dir := t.TempDir()
	writePage(t, dir, "wiki/infra/facts/k3s.md", "---\ntitle: K3s cluster\n---\nkubernetes cluster nodes scheduling pods deployment\n")
	writePage(t, dir, "wiki/finance/facts/invoice.md", "---\ntitle: Invoices\n---\ninvoice payment bookkeeping ledger reconciliation\n")
	return dir
}

func TestBM25Scorer_RanksTheWingWhosePagesMatch(t *testing.T) {
	s := wing.NewBM25Scorer(scorerBrain(t), []string{"infra", "finance"}, "")
	got := s.Score("notes about kubernetes cluster scheduling and pods")
	assert.Greater(t, got["infra"], got["finance"])
	assert.Greater(t, got["infra"], 0.0)
}

func TestBM25Scorer_ExcludesThePageBeingClassified(t *testing.T) {
	// A page must not vouch for its own wing when it is the backtest sample.
	s := wing.NewBM25Scorer(scorerBrain(t), []string{"infra", "finance"}, "wiki/infra/facts/k3s.md")
	got := s.Score("kubernetes cluster nodes scheduling pods deployment")
	assert.Zero(t, got["infra"], "the excluded page is the only infra match")
}

func TestBM25Scorer_NoUsableTermsScoresNothing(t *testing.T) {
	s := wing.NewBM25Scorer(scorerBrain(t), []string{"infra", "finance"}, "")
	assert.Empty(t, s.Score("a an to of"))
}