/*
 * Copyright (c) 2021 The Clymene Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package flags

import (
	"flag"
	"github.com/spf13/viper"
	"go.uber.org/zap"
	"go.uber.org/zap/zapcore"
)

const (
	logLevel = "log-level"
)

// SharedFlags holds flags configuration
type SharedFlags struct {
	// Logging holds logging configuration
	Logging logging
}

type logging struct {
	Level string
}

// AddLoggingFlag adds logging flag for SharedFlags
func AddLoggingFlag(flagSet *flag.FlagSet) {
	flagSet.String(logLevel, "info", "Minimal allowed log Level. For more levels see https://github.com/uber-go/zap")
}

// InitFromViper initializes SharedFlags with properties from viper
func (flags *SharedFlags) InitFromViper(v *viper.Viper) *SharedFlags {
	flags.Logging.Level = v.GetString(logLevel)
	return flags
}

// NewLogger returns logger based on configuration in SharedFlags
func (flags *SharedFlags) NewLogger(conf zap.Config, options ...zap.Option) (*zap.Logger, error) {
	var level zapcore.Level
	err := (&level).UnmarshalText([]byte(flags.Logging.Level))
	if err != nil {
		return nil, err
	}
	conf.Level = zap.NewAtomicLevelAt(level)
	return conf.Build(options...)
}
