block-accounting/backend/internal/pkg/logger/builder.go

package logger

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

type LoggerBuilder struct {
	local     bool
	addSource bool
	lvl       slog.Level
	writers   []io.Writer
}

func (b *LoggerBuilder) WithWriter(w io.Writer) *LoggerBuilder {
	b.writers = append(b.writers, w)

	return b
}

func (b *LoggerBuilder) WithLevel(l slog.Level) *LoggerBuilder {
	b.lvl = l

	return b
}

func (b *LoggerBuilder) Local() *LoggerBuilder {
	b.local = true

	return b
}

func (b *LoggerBuilder) WithSource() *LoggerBuilder {
	b.addSource = true

	return b
}

func (b *LoggerBuilder) Build() *slog.Logger {
	if len(b.writers) == 0 {
		b.writers = append(b.writers, os.Stdout)
	}

	w := io.MultiWriter(b.writers...)

	if b.local {
		opts := PrettyHandlerOptions{
			SlogOpts: &slog.HandlerOptions{
				Level:     b.lvl,
				AddSource: b.addSource,
			},
		}

		handler := opts.NewPrettyHandler(w)

		return slog.New(handler)
	}

	return newLogger(b.lvl, w)
}