package vectorstore_test

import (
	"context"
	"os"
	"testing"
	"time"

	"github.com/mathiasbq/hyperguild/ingestion/internal/vectorstore"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

// integration tests run against a real postgres18 + pgvector. Gated by
// BRAIN_PG_TEST_DSN so `task check` stays hermetic on hosts without a
// reachable database.
//
// To run:
//   BRAIN_PG_TEST_DSN='postgres://brain_app:pwd@127.0.0.1:5432/brain' \
//   go test ./internal/vectorstore/... -run Integration
func dsn(t *testing.T) string {
	t.Helper()
	v := os.Getenv("BRAIN_PG_TEST_DSN")
	if v == "" {
		t.Skip("BRAIN_PG_TEST_DSN not set; skipping pgvector integration tests")
	}
	return v
}

func freshStore(t *testing.T) (*vectorstore.PGStore, context.Context) {
	t.Helper()
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	t.Cleanup(cancel)
	s, err := vectorstore.New(ctx, dsn(t))
	require.NoError(t, err)
	t.Cleanup(s.Close)
	require.NoError(t, s.Init(ctx))
	// Clean slate per test.
	_, _ = s.KnownPathsWithTime(ctx)
	require.NoError(t, s.Delete(ctx, "%test-fixture%"))
	return s, ctx
}

func vec(dim int, fill float32) []float32 {
	v := make([]float32, dim)
	for i := range v {
		v[i] = fill
	}
	return v
}

func TestIntegration_UpsertAndSearch(t *testing.T) {
	s, ctx := freshStore(t)

	require.NoError(t, s.Upsert(ctx, "wiki/a.md", vec(768, 1.0)))
	require.NoError(t, s.Upsert(ctx, "wiki/b.md", vec(768, -1.0)))

	hits, err := s.Search(ctx, vec(768, 1.0), 2)
	require.NoError(t, err)
	require.GreaterOrEqual(t, len(hits), 1)
	assert.Equal(t, "wiki/a.md", hits[0].Path)
	assert.InDelta(t, 0.0, hits[0].Distance, 1e-5)

	t.Cleanup(func() {
		_ = s.Delete(ctx, "wiki/a.md")
		_ = s.Delete(ctx, "wiki/b.md")
	})
}

func TestIntegration_KnownPathsWithTime(t *testing.T) {
	s, ctx := freshStore(t)
	before := time.Now()
	require.NoError(t, s.Upsert(ctx, "wiki/k.md", vec(768, 0.5)))
	t.Cleanup(func() { _ = s.Delete(ctx, "wiki/k.md") })

	paths, err := s.KnownPathsWithTime(ctx)
	require.NoError(t, err)
	at, ok := paths["wiki/k.md"]
	require.True(t, ok)
	assert.False(t, at.IsZero(), "updated_at must not be zero")
	assert.WithinDuration(t, before, at, 5*time.Second, "updated_at must be recent")
}

func TestUpsert_RejectsWrongDimension(t *testing.T) {
	s := &vectorstore.PGStore{}
	err := s.Upsert(context.Background(), "x", vec(100, 0))
	require.Error(t, err)
}

func TestSearch_RejectsWrongDimension(t *testing.T) {
	s := &vectorstore.PGStore{}
	_, err := s.Search(context.Background(), vec(100, 0), 5)
	require.Error(t, err)
}