package server

import (
	"time"
)

// Defines default config settings (excluding limits, see below)
const (
	DefaultListenHTTP                = ":80"
	DefaultCacheDuration             = 12 * time.Hour
	DefaultKeepaliveInterval         = 55 * time.Second // Not too frequently to save battery (Android read timeout is 77s!)
	DefaultManagerInterval           = time.Minute
	DefaultAtSenderInterval          = 10 * time.Second
	DefaultMinDelay                  = 10 * time.Second
	DefaultMaxDelay                  = 3 * 24 * time.Hour
	DefaultFirebaseKeepaliveInterval = 3 * time.Hour // Not too frequently to save battery
)

// Defines all global and per-visitor limits
// - message size limit: the max number of bytes for a message
// - total topic limit: max number of topics overall
// - various attachment limits
const (
	DefaultMessageLengthLimit       = 4096 // Bytes
	DefaultTotalTopicLimit          = 15000
	DefaultAttachmentTotalSizeLimit = int64(10 * 1024 * 1024 * 1024) // 10 GB
	DefaultAttachmentFileSizeLimit  = int64(15 * 1024 * 1024)        // 15 MB
	DefaultAttachmentExpiryDuration = 3 * time.Hour
)

// Defines all per-visitor limits
// - per visitor subscription limit: max number of subscriptions (active HTTP connections) per per-visitor/IP
// - per visitor request limit: max number of PUT/GET/.. requests (here: 60 requests bucket, replenished at a rate of one per 10 seconds)
// - per visitor email limit: max number of emails (here: 16 email bucket, replenished at a rate of one per hour)
// - per visitor attachment size limit: total per-visitor attachment size in bytes to be stored on the server
// - per visitor attachment daily traffic limit: number of bytes that can be transferred to/from the server
const (
	DefaultVisitorSubscriptionLimit           = 30
	DefaultVisitorRequestLimitBurst           = 60
	DefaultVisitorRequestLimitReplenish       = 10 * time.Second
	DefaultVisitorEmailLimitBurst             = 16
	DefaultVisitorEmailLimitReplenish         = time.Hour
	DefaultVisitorAttachmentTotalSizeLimit    = 100 * 1024 * 1024 // 100 MB
	DefaultVisitorAttachmentDailyTrafficLimit = 500 * 1024 * 1024 // 500 MB
)

// Config is the main config struct for the application. Use New to instantiate a default config struct.
type Config struct {
	BaseURL                            string
	ListenHTTP                         string
	ListenHTTPS                        string
	KeyFile                            string
	CertFile                           string
	FirebaseKeyFile                    string
	CacheFile                          string
	CacheDuration                      time.Duration
	AttachmentCacheDir                 string
	AttachmentTotalSizeLimit           int64
	AttachmentFileSizeLimit            int64
	AttachmentExpiryDuration           time.Duration
	KeepaliveInterval                  time.Duration
	ManagerInterval                    time.Duration
	AtSenderInterval                   time.Duration
	FirebaseKeepaliveInterval          time.Duration
	SMTPSenderAddr                     string
	SMTPSenderUser                     string
	SMTPSenderPass                     string
	SMTPSenderFrom                     string
	SMTPServerListen                   string
	SMTPServerDomain                   string
	SMTPServerAddrPrefix               string
	MessageLimit                       int
	MinDelay                           time.Duration
	MaxDelay                           time.Duration
	TotalTopicLimit                    int
	TotalAttachmentSizeLimit           int64
	VisitorSubscriptionLimit           int
	VisitorAttachmentTotalSizeLimit    int64
	VisitorAttachmentDailyTrafficLimit int
	VisitorRequestLimitBurst           int
	VisitorRequestLimitReplenish       time.Duration
	VisitorEmailLimitBurst             int
	VisitorEmailLimitReplenish         time.Duration
	BehindProxy                        bool
}

// NewConfig instantiates a default new server config
func NewConfig() *Config {
	return &Config{
		BaseURL:                            "",
		ListenHTTP:                         DefaultListenHTTP,
		ListenHTTPS:                        "",
		KeyFile:                            "",
		CertFile:                           "",
		FirebaseKeyFile:                    "",
		CacheFile:                          "",
		CacheDuration:                      DefaultCacheDuration,
		AttachmentCacheDir:                 "",
		AttachmentTotalSizeLimit:           DefaultAttachmentTotalSizeLimit,
		AttachmentFileSizeLimit:            DefaultAttachmentFileSizeLimit,
		AttachmentExpiryDuration:           DefaultAttachmentExpiryDuration,
		KeepaliveInterval:                  DefaultKeepaliveInterval,
		ManagerInterval:                    DefaultManagerInterval,
		MessageLimit:                       DefaultMessageLengthLimit,
		MinDelay:                           DefaultMinDelay,
		MaxDelay:                           DefaultMaxDelay,
		AtSenderInterval:                   DefaultAtSenderInterval,
		FirebaseKeepaliveInterval:          DefaultFirebaseKeepaliveInterval,
		TotalTopicLimit:                    DefaultTotalTopicLimit,
		VisitorSubscriptionLimit:           DefaultVisitorSubscriptionLimit,
		VisitorAttachmentTotalSizeLimit:    DefaultVisitorAttachmentTotalSizeLimit,
		VisitorAttachmentDailyTrafficLimit: DefaultVisitorAttachmentDailyTrafficLimit,
		VisitorRequestLimitBurst:           DefaultVisitorRequestLimitBurst,
		VisitorRequestLimitReplenish:       DefaultVisitorRequestLimitReplenish,
		VisitorEmailLimitBurst:             DefaultVisitorEmailLimitBurst,
		VisitorEmailLimitReplenish:         DefaultVisitorEmailLimitReplenish,
		BehindProxy:                        false,
	}
}