package db

import (
	"context"
	"io"
	"log/slog"
	"os"
	"testing"
)

// TestMigrateAgainstPostgres runs the embedded migrations against a real
// Postgres indicated by MINSTREL_TEST_DATABASE_URL. Intended flow for local
// development: `docker compose up -d postgres` then
// `MINSTREL_TEST_DATABASE_URL=postgres://minstrel:minstrel@localhost:5432/minstrel?sslmode=disable go test ./...`.
// Skipped in `-short` mode (which is what CI runs) and when the env var is unset.
func TestMigrateAgainstPostgres(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping migration test in -short mode")
	}
	dsn := os.Getenv("MINSTREL_TEST_DATABASE_URL")
	if dsn == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set; skipping")
	}

	logger := slog.New(slog.NewTextHandler(io.Discard, nil))

	if err := Migrate(dsn, logger); err != nil {
		t.Fatalf("first Migrate: %v", err)
	}
	if err := Migrate(dsn, logger); err != nil {
		t.Fatalf("second Migrate (idempotency): %v", err)
	}

	pool, err := Open(context.Background(), dsn)
	if err != nil {
		t.Fatalf("Open: %v", err)
	}
	defer pool.Close()

	var count int
	if err := pool.QueryRow(context.Background(),
		`SELECT count(*) FROM schema_migrations`).Scan(&count); err != nil {
		t.Fatalf("query schema_migrations: %v", err)
	}
	if count == 0 {
		t.Fatal("schema_migrations empty after Migrate")
	}
}

func TestMigrationsFSListsFiles(t *testing.T) {
	entries, err := migrationsFS.ReadDir("migrations")
	if err != nil {
		t.Fatalf("read embedded dir: %v", err)
	}
	if len(entries) == 0 {
		t.Fatal("no migration files embedded")
	}
}