package config

import (
	"errors"
	"fmt"
	"strings"
)

type LogLevel string

const (
	LogLevelDebug LogLevel = "DEBUG"
	LogLevelInfo  LogLevel = "INFO"
	LogLevelWarn  LogLevel = "WARN"
	LogLevelError LogLevel = "ERROR"
)

func (l *LogLevel) UnmarshalText(data []byte) error {
	raw := strings.ToUpper(string(data))

	switch LogLevel(raw) {
	case LogLevelDebug, LogLevelInfo, LogLevelWarn, LogLevelError:
		*l = LogLevel(raw)
		return nil
	default:
		return fmt.Errorf("invalid log level: %q", data)
	}
}

type NodeConfig struct {
	Hostname          string   `toml:"hostname"`
	Endpoint          string   `toml:"endpoint"`
	KeepaliveInterval int      `toml:"keepalive_interval"`
	LogLevel          LogLevel `toml:"log_level"`

	BootstrapMaster string `toml:"bootstrap_master"`
	ListenOn        string `toml:"listen_on"`
	Port            int    `toml:"port"`
}

func (c NodeConfig) Validate() error {
	if c.Hostname == "" {
		return errors.New("missing hostname")
	}

	if c.Endpoint == "" {
		return errors.New("missing endpoint")
	}

	if c.KeepaliveInterval < 1 && c.KeepaliveInterval != -1 {
		return errors.New("invalid keepalive_interval")
	}

	return nil
}

func (c *NodeConfig) Merge(other NodeConfig) {
	if other.Hostname != "" {
		c.Hostname = other.Hostname
	}

	if other.Endpoint != "" {
		c.Endpoint = other.Endpoint
	}

	if other.BootstrapMaster != "" {
		c.BootstrapMaster = other.BootstrapMaster
	}

	if other.ListenOn != "" {
		c.ListenOn = other.ListenOn
	}

	if other.Port != 0 {
		c.Port = other.Port
	}

	if other.KeepaliveInterval != 0 {
		c.KeepaliveInterval = other.KeepaliveInterval
	}

	if other.LogLevel != "" {
		c.LogLevel = other.LogLevel
	}
}