package logger

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

	"go.uber.org/fx"
	"sneak.berlin/go/webhooker/internal/globals"
)

// nolint:revive // LoggerParams is a standard fx naming convention
type LoggerParams struct {
	fx.In
	Globals *globals.Globals
}

type Logger struct {
	logger *slog.Logger
	params LoggerParams
}

// nolint:revive // lc parameter is required by fx even if unused
func New(lc fx.Lifecycle, params LoggerParams) (*Logger, error) {
	l := new(Logger)
	l.params = params

	// Determine if we're running in a terminal
	tty := false
	if fileInfo, _ := os.Stdout.Stat(); (fileInfo.Mode() & os.ModeCharDevice) != 0 {
		tty = true
	}

	var handler slog.Handler
	opts := &slog.HandlerOptions{
		Level: slog.LevelInfo,
		ReplaceAttr: func(_ []string, a slog.Attr) slog.Attr { // nolint:revive // groups unused
			// Always use UTC for timestamps
			if a.Key == slog.TimeKey {
				if t, ok := a.Value.Any().(time.Time); ok {
					return slog.Time(slog.TimeKey, t.UTC())
				}
			}
			return a
		},
	}

	if tty {
		// Use text handler for terminal output (human-readable)
		handler = slog.NewTextHandler(os.Stdout, opts)
	} else {
		// Use JSON handler for production (machine-readable)
		handler = slog.NewJSONHandler(os.Stdout, opts)
	}

	l.logger = slog.New(handler)

	// Set as default logger
	slog.SetDefault(l.logger)

	return l, nil
}

func (l *Logger) EnableDebugLogging() {
	// Recreate logger with debug level
	tty := false
	if fileInfo, _ := os.Stdout.Stat(); (fileInfo.Mode() & os.ModeCharDevice) != 0 {
		tty = true
	}

	var handler slog.Handler
	opts := &slog.HandlerOptions{
		Level: slog.LevelDebug,
		ReplaceAttr: func(_ []string, a slog.Attr) slog.Attr { // nolint:revive // groups unused
			// Always use UTC for timestamps
			if a.Key == slog.TimeKey {
				if t, ok := a.Value.Any().(time.Time); ok {
					return slog.Time(slog.TimeKey, t.UTC())
				}
			}
			return a
		},
	}

	if tty {
		handler = slog.NewTextHandler(os.Stdout, opts)
	} else {
		handler = slog.NewJSONHandler(os.Stdout, opts)
	}

	l.logger = slog.New(handler)
	slog.SetDefault(l.logger)
	l.logger.Debug("debug logging enabled", "debug", true)
}

func (l *Logger) Get() *slog.Logger {
	return l.logger
}

func (l *Logger) Identify() {
	l.logger.Info("starting",
		"appname", l.params.Globals.Appname,
		"version", l.params.Globals.Version,
		"buildarch", l.params.Globals.Buildarch,
	)
}

// Helper methods to maintain compatibility with existing code
func (l *Logger) Writer() io.Writer {
	return os.Stdout
}