package client

import (
	"sync"
	"time"

	"git.loafle.net/commons_go/logging"

	"git.loafle.net/commons_go/rpc/protocol"
	crr "git.loafle.net/commons_go/rpc/registry"
	cuc "git.loafle.net/commons_go/util/context"
)

type ClientHandlers struct {
	Codec      protocol.ClientCodec
	RPCInvoker crr.RPCInvoker

	// Maximum request time.
	// Default value is DefaultRequestTimeout.
	RequestTimeout time.Duration
	// The maximum number of pending requests in the queue.
	//
	// The number of pending requsts should exceed the expected number
	// of concurrent goroutines calling client's methods.
	// Otherwise a lot of ClientError.Overflow errors may appear.
	//
	// Default is DefaultPendingMessages.
	PendingRequests int

	requestID    uint64
	requestIDMtx sync.Mutex
}

func (ch *ClientHandlers) ClientContext(parent cuc.Context) ClientContext {
	return newClientContext(parent)
}

func (ch *ClientHandlers) Init(clientCTX ClientContext) error {
	return nil
}

func (ch *ClientHandlers) Destroy(clientCTX ClientContext) {
	// no op
}

func (ch *ClientHandlers) GetCodec() protocol.ClientCodec {
	return ch.Codec
}

func (ch *ClientHandlers) GetRPCInvoker() crr.RPCInvoker {
	return ch.RPCInvoker
}

func (ch *ClientHandlers) GetRequestTimeout() time.Duration {
	return ch.RequestTimeout
}

func (ch *ClientHandlers) GetPendingRequests() int {
	return ch.PendingRequests
}

func (ch *ClientHandlers) GetRequestID() uint64 {
	var id uint64
	ch.requestIDMtx.Lock()
	ch.requestID++
	id = ch.requestID
	ch.requestIDMtx.Unlock()

	return id
}

func (ch *ClientHandlers) Validate() {
	if nil == ch.Codec {
		logging.Logger().Panic("RPC Client Handler: Codec must be specified")
	}

	if ch.RequestTimeout <= 0 {
		ch.RequestTimeout = DefaultRequestTimeout
	}
	if ch.PendingRequests <= 0 {
		ch.PendingRequests = DefaultPendingMessages
	}
}