package logging

import (
	"log/slog"
	"os"

	"github.com/lmittmann/tint"
)

// ---------- Standard log handling (terminal or file based) ----------

var logLevel slog.LevelVar
var fileLogger *os.File

// Set the logging to a particular level, quietly
func SetLevel(level slog.Level) {
	logLevel.Set(level)
}

// Enable debug level logging
func EnableDebug() {
	if logLevel.Level() > slog.LevelDebug {
		logLevel.Set(slog.LevelDebug)
		slog.Debug("Debug logging enabled")
	}
}

func LogToFile(logfile string) error {
	if fileLogger != nil {
		(*fileLogger).Close()
	}

	// Open the log file
	var err error
	fileLogger, err = os.OpenFile(logfile, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o600)
	if err != nil {
		return err
	}

	opts := &slog.HandlerOptions{
		Level: &logLevel,
	}
	handler := slog.NewJSONHandler(fileLogger, opts)
	logger := slog.New(handler)
	slog.SetDefault(logger)

	return nil
}

func Shutdown() error {
	var err error = nil
	if fileLogger != nil {
		err = (*fileLogger).Close()
		fileLogger = nil
	}
	return err
}

func LogToTerminal() {
	opts := &tint.Options{
		Level:      &logLevel,
		TimeFormat: "*",
	}
	handler := tint.NewTextHandler(os.Stdout, opts)
	logger := slog.New(handler)
	slog.SetDefault(logger)
}

// IsJSONHandler reports whether h writes JSON, as the file logger does.
func IsJSONHandler(h slog.Handler) bool {
	_, ok := h.(*slog.JSONHandler)
	return ok
}

func IsFileLogger() bool {
	return fileLogger != nil
}

func IsDebugEnabled() bool {
	return logLevel.Level() <= slog.LevelDebug
}