package logger

import (
	"bytes"
	"log"
	"strings"
	"testing"
)

func captureLogs(t *testing.T) *bytes.Buffer {
	t.Helper()
	var buf bytes.Buffer
	oldWriter := log.Writer()
	oldFlags := log.Flags()
	log.SetOutput(&buf)
	log.SetFlags(0)
	t.Cleanup(func() {
		log.SetOutput(oldWriter)
		log.SetFlags(oldFlags)
		SetVerbose(false)
	})
	return &buf
}

func TestVerboseFlag(t *testing.T) {
	SetVerbose(true)
	if !IsVerbose() {
		t.Fatal("IsVerbose() = false, want true")
	}
	SetVerbose(false)
	if IsVerbose() {
		t.Fatal("IsVerbose() = true, want false")
	}
}

func TestLoggingFunctions(t *testing.T) {
	buf := captureLogs(t)

	Info("info")
	Infof("%s", "infof")
	Warn("warn")
	Warnf("%s", "warnf")
	Error("error")
	Errorf("%s", "errorf")

	got := buf.String()
	for _, want := range []string{"info", "infof", "warn", "warnf", "error", "errorf"} {
		if !strings.Contains(got, want) {
			t.Fatalf("log output %q does not contain %q", got, want)
		}
	}
}

func TestVerboseAndDebugLogging(t *testing.T) {
	buf := captureLogs(t)

	Verbosef("%s", "hidden")
	Debugf("%s", "hidden-debug")
	if got := buf.String(); got != "" {
		t.Fatalf("unexpected log output when verbose disabled: %q", got)
	}

	SetVerbose(true)
	Verbosef("%s", "visible")
	Debugf("%s", "visible-debug")
	got := buf.String()
	for _, want := range []string{"visible", "visible-debug"} {
		if !strings.Contains(got, want) {
			t.Fatalf("log output %q does not contain %q", got, want)
		}
	}
}