package traceimpact

import (
	"context"
	"time"

	"github.com/jackc/pgx/v5/pgxpool"
)

// Open uses the record tables when migration 00059 is present.
// Before that migration, it keeps an in-memory ledger so the process can still boot.
func Open(pool *pgxpool.Pool) *Service {
	if pool == nil {
		return NewMemoryService()
	}
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	defer cancel()
	var exists bool
	err := pool.QueryRow(ctx, `
		SELECT EXISTS (
			SELECT 1 FROM information_schema.tables
			WHERE table_schema = 'public' AND table_name = 'project_trace_items'
		)`).Scan(&exists)
	if err != nil || !exists {
		return NewMemoryService()
	}
	return NewService(newPGStore(pool))
}