package server

import (
	"sync/atomic"
	"time"
)

type ReadWriteHandler interface {
	GetMaxMessageSize() int64
	GetReadBufferSize() int
	GetWriteBufferSize() int
	GetReadTimeout() time.Duration
	GetWriteTimeout() time.Duration
}

type ReadWriteHandlers struct {
	MaxMessageSize int64 `json:"maxMessageSize,omitempty"`
	// Per-connection buffer size for requests' reading.
	// This also limits the maximum header size.
	//
	// Increase this buffer if your clients send multi-KB RequestURIs
	// and/or multi-KB headers (for example, BIG cookies).
	//
	// Default buffer size is used if not set.
	ReadBufferSize int `json:"readBufferSize,omitempty"`
	// Per-connection buffer size for responses' writing.
	//
	// Default buffer size is used if not set.
	WriteBufferSize int `json:"writeBufferSize,omitempty"`
	// Maximum duration for reading the full request (including body).
	//
	// This also limits the maximum duration for idle keep-alive
	// connections.
	//
	// By default request read timeout is unlimited.
	ReadTimeout time.Duration `json:"readTimeout,omitempty"`

	// Maximum duration for writing the full response (including body).
	//
	// By default response write timeout is unlimited.
	WriteTimeout time.Duration `json:"writeTimeout,omitempty"`

	validated atomic.Value
}

func (rwh *ReadWriteHandlers) GetMaxMessageSize() int64 {
	return rwh.MaxMessageSize
}
func (rwh *ReadWriteHandlers) GetReadBufferSize() int {
	return rwh.ReadBufferSize
}
func (rwh *ReadWriteHandlers) GetWriteBufferSize() int {
	return rwh.WriteBufferSize
}
func (rwh *ReadWriteHandlers) GetReadTimeout() time.Duration {
	return rwh.ReadTimeout
}
func (rwh *ReadWriteHandlers) GetWriteTimeout() time.Duration {
	return rwh.WriteTimeout
}

func (rwh *ReadWriteHandlers) Clone() *ReadWriteHandlers {
	return &ReadWriteHandlers{
		MaxMessageSize:  rwh.MaxMessageSize,
		ReadBufferSize:  rwh.ReadBufferSize,
		WriteBufferSize: rwh.WriteBufferSize,
		ReadTimeout:     rwh.ReadTimeout,
		WriteTimeout:    rwh.WriteTimeout,
		validated:       rwh.validated,
	}
}

func (rwh *ReadWriteHandlers) Validate() error {
	if nil != rwh.validated.Load() {
		return nil
	}
	rwh.validated.Store(true)

	if rwh.MaxMessageSize <= 0 {
		rwh.MaxMessageSize = DefaultMaxMessageSize
	}
	if rwh.ReadBufferSize <= 0 {
		rwh.ReadBufferSize = DefaultReadBufferSize
	}
	if rwh.WriteBufferSize <= 0 {
		rwh.WriteBufferSize = DefaultWriteBufferSize
	}
	if rwh.ReadTimeout <= 0 {
		rwh.ReadTimeout = DefaultReadTimeout
	} else {
		rwh.ReadTimeout = rwh.ReadTimeout * time.Second
	}

	if rwh.WriteTimeout <= 0 {
		rwh.WriteTimeout = DefaultWriteTimeout
	} else {
		rwh.WriteTimeout = rwh.WriteTimeout * time.Second
	}

	return nil
}