//
// logging.go
// Copyright (C) 2023 tiglog <me@tiglog.com>
//
// Distributed under terms of the MIT license.
//

package sqldb

import "fmt"

// SqldbLogger is a deprecated alias of Logger.
type SqldbLogger = Logger

// Logger is the type that sqldb uses to log SQL statements.
// See DbMap.TraceOn.
type Logger interface {
	Printf(format string, v ...interface{})
}

// TraceOn turns on SQL statement logging for this DbMap.  After this is
// called, all SQL statements will be sent to the logger.  If prefix is
// a non-empty string, it will be written to the front of all logged
// strings, which can aid in filtering log lines.
//
// Use TraceOn if you want to spy on the SQL statements that sqldb
// generates.
//
// Note that the base log.Logger type satisfies Logger, but adapters can
// easily be written for other logging packages (e.g., the golang-sanctioned
// glog framework).
func (m *DbMap) TraceOn(prefix string, logger Logger) {
	m.logger = logger
	if prefix == "" {
		m.logPrefix = prefix
	} else {
		m.logPrefix = fmt.Sprintf("%s ", prefix)
	}
}

// TraceOff turns off tracing. It is idempotent.
func (m *DbMap) TraceOff() {
	m.logger = nil
	m.logPrefix = ""
}