package logger

import (
	"io"
	"log/slog"

	"github.com/ThreeDotsLabs/watermill"
)

const (
	LevelTrace = slog.Level(-5)
)

func LogFieldsToSlogAttrs(in watermill.LogFields) []slog.Attr {
	attrs := make([]slog.Attr, 0)
	for k, v := range in {
		attrs = append(attrs, slog.Attr{
			Key:   k,
			Value: slog.AnyValue(v),
		})
	}
	return attrs
}

type WrappedSlogger struct {
	loggers []*slog.Logger
}

type LogConfig struct {
	Format string
	Writer io.Writer
	Level  int
}

func NewWrappedSlogger(configs ...LogConfig) *WrappedSlogger {

	loggers := make([]*slog.Logger, 0)
	for _, config := range configs {

		opts := &slog.HandlerOptions{
			Level: slog.Level(config.Level),
		}

		var handler slog.Handler

		switch config.Format {
		case "json":
			handler = slog.NewJSONHandler(config.Writer, opts)
		case "text":
			handler = slog.NewTextHandler(config.Writer, opts)

		}

		loggers = append(loggers, slog.New(handler))
	}

	return &WrappedSlogger{
		loggers: loggers,
	}
}

func (wl *WrappedSlogger) Error(msg string, err error, fields watermill.LogFields) {
	attrs := LogFieldsToSlogAttrs(fields)
	for _, l := range wl.loggers {
		l.LogAttrs(nil, slog.LevelError, msg, attrs...)
	}
}

func (wl *WrappedSlogger) Info(msg string, fields watermill.LogFields) {
	attrs := LogFieldsToSlogAttrs(fields)
	for _, l := range wl.loggers {
		l.LogAttrs(nil, slog.LevelInfo, msg, attrs...)
	}
}

func (wl *WrappedSlogger) Debug(msg string, fields watermill.LogFields) {
	attrs := LogFieldsToSlogAttrs(fields)
	for _, l := range wl.loggers {
		l.LogAttrs(nil, slog.LevelDebug, msg, attrs...)
	}
}

func (wl *WrappedSlogger) Trace(msg string, fields watermill.LogFields) {
	attrs := LogFieldsToSlogAttrs(fields)
	for _, l := range wl.loggers {
		l.LogAttrs(nil, LevelTrace, msg, attrs...)
	}
}

func (wl *WrappedSlogger) With(fields watermill.LogFields) watermill.LoggerAdapter {
	attrs := LogFieldsToSlogAttrs(fields)
	loggerArgs := make([]any, len(attrs))
	for idx, attr := range attrs {
		loggerArgs[idx] = attr
	}
	newLoggers := make([]*slog.Logger, 0)
	for _, l := range wl.loggers {
		newLoggers = append(newLoggers, l.With(loggerArgs...))
	}
	return &WrappedSlogger{loggers: newLoggers}

}