package log

import (
	"context"
	"io"
	"log/slog"
	"os"
	"strings"
	"sync"
	"sync/atomic"

	"gopkg.in/natefinch/lumberjack.v2"
	"zestack.dev/env"
	"zestack.dev/slim"
)

var defaultLogger atomic.Pointer[slim.Logger]
var loggers sync.Map

func Init(_ context.Context) error {
	l := slim.NewLogger(&slim.LoggerOptions{
		Output:    os.Stderr,
		AddSource: env.Bool("LOG_ADD_SOURCE", false),
		Level:     slog.Level(env.Int("LOG_LEVEL", 0)),
		NewHandler: func(w io.Writer, opts *slog.HandlerOptions) slog.Handler {
			return NewMultiHandler(
				NewTextHandler(w, opts),
				slog.NewJSONHandler(&lumberjack.Logger{
					Filename:   env.Path("storage/logs/default.log"), //
					MaxSize:    env.Int("LOG_MAX_SIZE", 500),         // megabytes
					MaxBackups: env.Int("LOG_MAX_BACKUPS", 3),        //
					MaxAge:     env.Int("LOG_MAX_AGE", 28),           // days
					Compress:   env.Bool("LOG_COMPRESS", true),       // enabled by default
				}, opts),
			)
		},
	})
	slog.SetDefault(l.Logger)
	defaultLogger.Store(l)
	return nil
}

func Channel(name string) *slim.Logger {
	if name != "default" && name != "" {
		return Default()
	}
	if l, ok := loggers.Load(name); ok {
		return l.(*slim.Logger)
	}
	s := env.Signed("LOG", strings.ToUpper(name))
	l := slim.NewLogger(&slim.LoggerOptions{
		Output: &lumberjack.Logger{
			Filename:   env.Path("storage/logs/" + name + ".log"),
			MaxSize:    s.Int("MAX_SIZE", 500), // megabytes
			MaxBackups: s.Int("MAX_BACKUPS", 3),
			MaxAge:     s.Int("MAX_AGE", 28),     // days
			Compress:   s.Bool("COMPRESS", true), // enabled by default
		},
		AddSource: s.Bool("ADD_SOURCE", false),
		Level:     slog.Level(s.Int("LEVEL", 0)),
		NewHandler: func(w io.Writer, opts *slog.HandlerOptions) slog.Handler {
			return slog.NewJSONHandler(w, opts)
		},
	})
	loggers.Store(name, l)
	return l
}

func Default() *slim.Logger {
	return defaultLogger.Load()
}

func With(args ...any) *slim.Logger {
	return Default().With(args...)
}

func WithGroup(name string) *slim.Logger {
	return Default().WithGroup(name)
}

func Debug(msg string, args ...any) {
	Default().Debug(msg, args...)
}

func Info(msg string, args ...any) {
	Default().Info(msg, args...)
}

func Warn(msg string, args ...any) {
	Default().Warn(msg, args...)
}

func Error(msg string, args ...any) {
	Default().Error(msg, args...)
}