package netsync

import (
	"errors"
	"math/rand"
	"net"

	wire "github.com/tendermint/go-wire"

	"github.com/bytom/consensus"
	"github.com/bytom/protocol/bc/types"
	"github.com/bytom/test/mock"
)

type P2PPeer struct {
	id   string
	ip   *net.IPAddr
	flag consensus.ServiceFlag

	srcPeer    *P2PPeer
	remoteNode *SyncManager
	msgCh      chan []byte
	async      bool
}

func NewP2PPeer(addr, id string, flag consensus.ServiceFlag) *P2PPeer {
	return &P2PPeer{
		id:    id,
		ip:    &net.IPAddr{IP: net.ParseIP(addr)},
		flag:  flag,
		msgCh: make(chan []byte),
		async: false,
	}
}

func (p *P2PPeer) Addr() net.Addr {
	return p.ip
}

func (p *P2PPeer) ID() string {
	return p.id
}

func (p *P2PPeer) ServiceFlag() consensus.ServiceFlag {
	return p.flag
}

func (p *P2PPeer) SetConnection(srcPeer *P2PPeer, node *SyncManager) {
	p.srcPeer = srcPeer
	p.remoteNode = node
}

func (p *P2PPeer) TrySend(b byte, msg interface{}) bool {
	msgBytes := wire.BinaryBytes(msg)
	if p.async {
		p.msgCh <- msgBytes
	} else {
		msgType, msg, _ := DecodeMessage(msgBytes)
		p.remoteNode.processMsg(p.srcPeer, msgType, msg)
	}
	return true
}

func (p *P2PPeer) setAsync(b bool) {
	p.async = b
}

func (p *P2PPeer) postMan() {
	for msgBytes := range p.msgCh {
		msgType, msg, _ := DecodeMessage(msgBytes)
		p.remoteNode.processMsg(p.srcPeer, msgType, msg)
	}
}

type PeerSet struct{}

func NewPeerSet() *PeerSet {
	return &PeerSet{}
}

func (ps *PeerSet) AddBannedPeer(string) error { return nil }
func (ps *PeerSet) StopPeerGracefully(string)  {}

type NetWork struct {
	nodes map[*SyncManager]P2PPeer
}

func NewNetWork() *NetWork {
	return &NetWork{map[*SyncManager]P2PPeer{}}
}

func (nw *NetWork) Register(node *SyncManager, addr, id string, flag consensus.ServiceFlag) {
	peer := NewP2PPeer(addr, id, flag)
	nw.nodes[node] = *peer
}

func (nw *NetWork) HandsShake(nodeA, nodeB *SyncManager) error {
	B2A, ok := nw.nodes[nodeA]
	if !ok {
		return errors.New("can't find nodeA's p2p peer on network")
	}
	A2B, ok := nw.nodes[nodeB]
	if !ok {
		return errors.New("can't find nodeB's p2p peer on network")
	}

	A2B.SetConnection(&B2A, nodeB)
	B2A.SetConnection(&A2B, nodeA)
	go A2B.postMan()
	go B2A.postMan()

	nodeA.handleStatusRequestMsg(&A2B)
	nodeB.handleStatusRequestMsg(&B2A)

	A2B.setAsync(true)
	B2A.setAsync(true)
	return nil
}

func mockBlocks(startBlock *types.Block, height uint64) []*types.Block {
	blocks := []*types.Block{}
	indexBlock := &types.Block{}
	if startBlock == nil {
		indexBlock = &types.Block{BlockHeader: types.BlockHeader{Nonce: uint64(rand.Uint32())}}
		blocks = append(blocks, indexBlock)
	} else {
		indexBlock = startBlock
	}

	for indexBlock.Height < height {
		block := &types.Block{
			BlockHeader: types.BlockHeader{
				Height:            indexBlock.Height + 1,
				PreviousBlockHash: indexBlock.Hash(),
				Nonce:             uint64(rand.Uint32()),
			},
		}
		blocks = append(blocks, block)
		indexBlock = block
	}
	return blocks
}

func mockSync(blocks []*types.Block) *SyncManager {
	chain := mock.NewChain()
	peers := newPeerSet(NewPeerSet())
	chain.SetBestBlockHeader(&blocks[len(blocks)-1].BlockHeader)
	for _, block := range blocks {
		chain.SetBlockByHeight(block.Height, block)
	}

	genesis, _ := chain.GetHeaderByHeight(0)
	return &SyncManager{
		genesisHash: genesis.Hash(),
		chain:       chain,
		blockKeeper: newBlockKeeper(chain, peers),
		peers:       peers,
	}
}