package database

import (
	"context"
	"log/slog"

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

	"git.unkin.net/unkin/golib/pg"

	"git.unkin.net/unkin/forgebot/migrations"
)

// migrationLockName names the cluster-wide advisory lock the migration run
// contends for. golib derives the key as FNV-1a/64 of this name, so every
// replica must pass the same string to stay mutually exclusive.
const migrationLockName = "forgebot-migrations"

type DB struct {
	Pool *pgxpool.Pool
}

// New opens the pool and brings the schema up to date before returning, so the
// API never serves against a half-migrated database. log may be nil.
func New(ctx context.Context, dsn string, log *slog.Logger) (*DB, error) {
	pool, err := pg.NewMigrated(ctx, dsn, migrations.FS, pg.MigrateOptions{
		LockName: migrationLockName,
		Logger:   log,
	})
	if err != nil {
		return nil, err
	}
	return &DB{Pool: pool}, nil
}

func (db *DB) Close() {
	db.Pool.Close()
}

func (db *DB) Healthy(ctx context.Context) bool {
	return db.Pool.Ping(ctx) == nil
}