// Package store persists the master's state in Postgres.
package store

import (
	"context"
	"fmt"

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

// Store is the Postgres-backed storage for the master.
type Store struct {
	pool *pgxpool.Pool
}

// Open connects to Postgres and applies pending migrations.
func Open(ctx context.Context, url string) (*Store, error) {
	cfg, err := pgxpool.ParseConfig(url)
	if err != nil {
		return nil, fmt.Errorf("parse DATABASE_URL: %w", err)
	}
	return openWithConfig(ctx, cfg)
}

func openWithConfig(ctx context.Context, cfg *pgxpool.Config) (*Store, error) {
	pool, err := pgxpool.NewWithConfig(ctx, cfg)
	if err != nil {
		return nil, fmt.Errorf("connect postgres: %w", err)
	}
	if err := migrate(ctx, pool); err != nil {
		pool.Close()
		return nil, err
	}
	return &Store{pool: pool}, nil
}

// Close releases the connection pool.
func (s *Store) Close() { s.pool.Close() }

// Ping checks that Postgres answers. Used by /healthz.
func (s *Store) Ping(ctx context.Context) error { return s.pool.Ping(ctx) }