package main

import (
	"bytes"
	"errors"
	"fmt"
	"log"
	"net/url"
	"strconv"
	"time"
)

const (
	POLONIEX_API_URL                = "https://poloniex.com"
	POLONIEX_API_TRADING_ENDPOINT   = "tradingApi"
	POLONIEX_API_VERSION            = "1"
	POLONIEX_BALANCES               = "returnBalances"
	POLONIEX_BALANCES_COMPLETE      = "returnCompleteBalances"
	POLONIEX_DEPOSIT_ADDRESSES      = "returnDepositAddresses"
	POLONIEX_GENERATE_NEW_ADDRESS   = "generateNewAddress"
	POLONIEX_DEPOSITS_WITHDRAWALS   = "returnDepositsWithdrawals"
	POLONIEX_ORDERS                 = "returnOpenOrders"
	POLONIEX_TRADE_HISTORY          = "returnTradeHistory"
	POLONIEX_ORDER_BUY              = "buy"
	POLONIEX_ORDER_SELL             = "sell"
	POLONIEX_ORDER_ORDER            = "cancelOrder"
	POLONIEX_WITHDRAW               = "withdraw"
	POLONIEX_AVAILABLE_BALANCES     = "returnAvailableAccountBalances"
	POLONIEX_TRADABLE_BALANCES      = "returnTradableBalances"
	POLONIEX_TRANSFER_BALANCE       = "transferBalance"
	POLONIEX_MARGIN_ACCOUNT_SUMMARY = "returnMarginAccountSummary"
	POLONIEX_MARGIN_BUY             = "marginBuy"
	POLONIEX_MARGIN_SELL            = "marginSell"
	POLONIEX_MARGIN_POSITION        = "getMarginPosition"
	POLONIEX_MARGIN_POSITION_CLOSE  = "closeMarginPosition"
	POLONIEX_CREATE_LOAN_OFFER      = "createLoanOffer"
	POLONIEX_CANCEL_LOAN_OFFER      = "cancelLoanOffer"
	POLONIEX_OPEN_LOAN_OFFERS       = "returnOpenLoanOffers"
	POLONIEX_ACTIVE_LOANS           = "returnActiveLoans"
	POLONIEX_AUTO_RENEW             = "toggleAutoRenew"
)

type Poloniex struct {
	Name                    string
	Enabled                 bool
	Verbose                 bool
	Websocket               bool
	RESTPollingDelay        time.Duration
	AuthenticatedAPISupport bool
	AccessKey, SecretKey    string
	Fee                     float64
	BaseCurrencies          []string
	AvailablePairs          []string
	EnabledPairs            []string
}

type PoloniexTicker struct {
	Last          float64 `json:"last,string"`
	LowestAsk     float64 `json:"lowestAsk,string"`
	HighestBid    float64 `json:"highestBid,string"`
	PercentChange float64 `json:"percentChange,string"`
	BaseVolume    float64 `json:"baseVolume,string"`
	QuoteVolume   float64 `json:"quoteVolume,string"`
	IsFrozen      int     `json:"isFrozen,string"`
	High24Hr      float64 `json:"high24hr,string"`
	Low24Hr       float64 `json:"low24hr,string"`
}

func (p *Poloniex) SetDefaults() {
	p.Name = "Poloniex"
	p.Enabled = true
	p.Fee = 0
	p.Verbose = false
	p.Websocket = false
	p.RESTPollingDelay = 10
}

func (p *Poloniex) GetName() string {
	return p.Name
}

func (p *Poloniex) SetEnabled(enabled bool) {
	p.Enabled = enabled
}

func (p *Poloniex) IsEnabled() bool {
	return p.Enabled
}

func (p *Poloniex) SetAPIKeys(apiKey, apiSecret string) {
	p.AccessKey = apiKey
	p.SecretKey = apiSecret
}

func (p *Poloniex) GetFee() float64 {
	return p.Fee
}

func (p *Poloniex) Run() {
	if p.Verbose {
		log.Printf("%s Websocket: %s (url: %s).\n", p.GetName(), IsEnabled(p.Websocket), POLONIEX_WEBSOCKET_ADDRESS)
		log.Printf("%s polling delay: %ds.\n", p.GetName(), p.RESTPollingDelay)
		log.Printf("%s %d currencies enabled: %s.\n", p.GetName(), len(p.EnabledPairs), p.EnabledPairs)
	}

	if p.Websocket {
		go p.WebsocketClient()
	}

	for p.Enabled {
		for _, x := range p.EnabledPairs {
			currency := x
			go func() {
				ticker, err := p.GetTicker()
				if err != nil {
					log.Println(err)
					return
				}
				log.Printf("Poloniex %s Last %f High %f Low %f Volume %f\n", currency, ticker[currency].Last, ticker[currency].High24Hr, ticker[currency].Low24Hr, ticker[currency].QuoteVolume)
				//AddExchangeInfo(p.GetName(), currency[0:3], currency[3:], ticker.Last, ticker.Volume)
			}()
		}
		time.Sleep(time.Second * p.RESTPollingDelay)
	}
}

func (p *Poloniex) GetTicker() (map[string]PoloniexTicker, error) {
	type response struct {
		Data map[string]PoloniexTicker
	}

	resp := response{}
	path := fmt.Sprintf("%s/public?command=returnTicker", POLONIEX_API_URL)
	err := SendHTTPGetRequest(path, true, &resp.Data)

	if err != nil {
		return resp.Data, err
	}
	return resp.Data, nil
}

func (p *Poloniex) GetVolume() (interface{}, error) {
	var resp interface{}
	path := fmt.Sprintf("%s/public?command=return24hVolume", POLONIEX_API_URL)
	err := SendHTTPGetRequest(path, true, &resp)

	if err != nil {
		return resp, err
	}
	return resp, nil
}

type PoloniexOrderbook struct {
	Asks     [][]interface{} `json:"asks"`
	Bids     [][]interface{} `json:"bids"`
	IsFrozen string          `json:"isFrozen"`
}

//TO-DO: add support for individual pair depth fetching
func (p *Poloniex) GetOrderbook(currencyPair string, depth int) (map[string]PoloniexOrderbook, error) {
	type Response struct {
		Data map[string]PoloniexOrderbook
	}

	vals := url.Values{}
	vals.Set("currencyPair", currencyPair)

	if depth != 0 {
		vals.Set("depth", strconv.Itoa(depth))
	}

	resp := Response{}
	path := fmt.Sprintf("%s/public?command=returnOrderBook&%s", POLONIEX_API_URL, vals.Encode())
	err := SendHTTPGetRequest(path, true, &resp.Data)

	if err != nil {
		return resp.Data, err
	}
	return resp.Data, nil
}

type PoloniexTradeHistory struct {
	GlobalTradeID int64   `json:"globalTradeID"`
	TradeID       int64   `json:"tradeID"`
	Date          string  `json:"date"`
	Type          string  `json:"type"`
	Rate          float64 `json:"rate,string"`
	Amount        float64 `json:"amount,string"`
	Total         float64 `json:"total,string"`
}

func (p *Poloniex) GetTradeHistory(currencyPair, start, end string) ([]PoloniexTradeHistory, error) {
	vals := url.Values{}
	vals.Set("currencyPair", currencyPair)

	if start != "" {
		vals.Set("start", start)
	}

	if end != "" {
		vals.Set("end", end)
	}

	resp := []PoloniexTradeHistory{}
	path := fmt.Sprintf("%s/public?command=returnTradeHistory&%s", POLONIEX_API_URL, vals.Encode())
	err := SendHTTPGetRequest(path, true, &resp)

	if err != nil {
		return nil, err
	}
	return resp, nil
}

type PoloniexChartData struct {
	Date            int     `json:"date"`
	High            float64 `json:"high"`
	Low             float64 `json:"low"`
	Open            float64 `json:"open"`
	Close           float64 `json:"close"`
	Volume          float64 `json:"volume"`
	QuoteVolume     float64 `json:"quoteVolume"`
	WeightedAverage float64 `json:"weightedAverage"`
}

func (p *Poloniex) GetChartData(currencyPair, start, end, period string) ([]PoloniexChartData, error) {
	vals := url.Values{}
	vals.Set("currencyPair", currencyPair)

	if start != "" {
		vals.Set("start", start)
	}

	if end != "" {
		vals.Set("end", end)
	}

	if period != "" {
		vals.Set("period", period)
	}

	resp := []PoloniexChartData{}
	path := fmt.Sprintf("%s/public?command=returnChartData&%s", POLONIEX_API_URL, vals.Encode())
	err := SendHTTPGetRequest(path, true, &resp)

	if err != nil {
		return nil, err
	}
	return resp, nil
}

type PoloniexCurrencies struct {
	Name               string      `json:"name"`
	MaxDailyWithdrawal string      `json:"maxDailyWithdrawal"`
	TxFee              float64     `json:"txFee,string"`
	MinConfirmations   int         `json:"minConf"`
	DepositAddresses   interface{} `json:"depositAddress"`
	Disabled           int         `json:"disabled"`
	Delisted           int         `json:"delisted"`
	Frozen             int         `json:"frozen"`
}

func (p *Poloniex) GetCurrencies() (map[string]PoloniexCurrencies, error) {
	type Response struct {
		Data map[string]PoloniexCurrencies
	}
	resp := Response{}
	path := fmt.Sprintf("%s/public?command=returnCurrencies", POLONIEX_API_URL)
	err := SendHTTPGetRequest(path, true, &resp.Data)

	if err != nil {
		return resp.Data, err
	}
	return resp.Data, nil
}

type PoloniexLoanOrder struct {
	Rate     float64 `json:"rate,string"`
	Amount   float64 `json:"amount,string"`
	RangeMin int     `json:"rangeMin"`
	RangeMax int     `json:"rangeMax"`
}

type PoloniexLoanOrders struct {
	Offers  []PoloniexLoanOrder `json:"offers"`
	Demands []PoloniexLoanOrder `json:"demands"`
}

func (p *Poloniex) GetLoanOrders(currency string) (PoloniexLoanOrders, error) {
	resp := PoloniexLoanOrders{}
	path := fmt.Sprintf("%s/public?command=returnLoanOrders&currency=%s", POLONIEX_API_URL, currency)
	err := SendHTTPGetRequest(path, true, &resp)

	if err != nil {
		return resp, err
	}
	return resp, nil
}

type PoloniexBalance struct {
	Currency map[string]float64
}

func (p *Poloniex) GetBalances() (PoloniexBalance, error) {
	var result interface{}
	err := p.SendAuthenticatedHTTPRequest("POST", POLONIEX_BALANCES, url.Values{}, &result)

	if err != nil {
		return PoloniexBalance{}, err
	}

	data := result.(map[string]interface{})
	balance := PoloniexBalance{}
	balance.Currency = make(map[string]float64)

	for x, y := range data {
		balance.Currency[x], _ = strconv.ParseFloat(y.(string), 64)
	}

	return balance, nil
}

type PoloniexCompleteBalance struct {
	Available float64
	OnOrders  float64
	BTCValue  float64
}

type PoloniexCompleteBalances struct {
	Currency map[string]PoloniexCompleteBalance
}

func (p *Poloniex) GetCompleteBalances() (PoloniexCompleteBalances, error) {
	var result interface{}
	err := p.SendAuthenticatedHTTPRequest("POST", POLONIEX_BALANCES_COMPLETE, url.Values{}, &result)

	if err != nil {
		return PoloniexCompleteBalances{}, err
	}

	data := result.(map[string]interface{})
	balance := PoloniexCompleteBalances{}
	balance.Currency = make(map[string]PoloniexCompleteBalance)

	for x, y := range data {
		dataVals := y.(map[string]interface{})
		balancesData := PoloniexCompleteBalance{}
		balancesData.Available, _ = strconv.ParseFloat(dataVals["available"].(string), 64)
		balancesData.OnOrders, _ = strconv.ParseFloat(dataVals["onOrders"].(string), 64)
		balancesData.BTCValue, _ = strconv.ParseFloat(dataVals["btcValue"].(string), 64)
		balance.Currency[x] = balancesData
	}

	return balance, nil
}

type PoloniexDepositAddresses struct {
	Addresses map[string]string
}

func (p *Poloniex) GetDepositAddresses() (PoloniexDepositAddresses, error) {
	var result interface{}
	addresses := PoloniexDepositAddresses{}
	err := p.SendAuthenticatedHTTPRequest("POST", POLONIEX_DEPOSIT_ADDRESSES, url.Values{}, &result)

	if err != nil {
		return addresses, err
	}

	addresses.Addresses = make(map[string]string)
	data := result.(map[string]interface{})
	for x, y := range data {
		addresses.Addresses[x] = y.(string)
	}

	return addresses, nil
}

func (p *Poloniex) GenerateNewAddress(currency string) (string, error) {
	type Response struct {
		Success  int
		Error    string
		Response string
	}
	resp := Response{}
	values := url.Values{}
	values.Set("currency", currency)

	err := p.SendAuthenticatedHTTPRequest("POST", POLONIEX_GENERATE_NEW_ADDRESS, values, &resp)

	if err != nil {
		return "", err
	}

	if resp.Error != "" {
		return "", errors.New(resp.Error)
	}

	return resp.Response, nil
}

type PoloniexDepositsWithdrawals struct {
	Deposits []struct {
		Currency      string    `json:"currency"`
		Address       string    `json:"address"`
		Amount        float64   `json:"amount,string"`
		Confirmations int       `json:"confirmations"`
		TransactionID string    `json:"txid"`
		Timestamp     time.Time `json:"timestamp"`
		Status        string    `json:"string"`
	} `json:"deposits"`
	Withdrawals []struct {
		WithdrawalNumber int64     `json:"withdrawalNumber"`
		Currency         string    `json:"currency"`
		Address          string    `json:"address"`
		Amount           float64   `json:"amount,string"`
		Confirmations    int       `json:"confirmations"`
		TransactionID    string    `json:"txid"`
		Timestamp        time.Time `json:"timestamp"`
		Status           string    `json:"string"`
		IPAddress        string    `json:"ipAddress"`
	} `json:"withdrawals"`
}

func (p *Poloniex) GetDepositsWithdrawals(start, end string) (PoloniexDepositsWithdrawals, error) {
	resp := PoloniexDepositsWithdrawals{}
	values := url.Values{}

	if start != "" {
		values.Set("start", start)
	} else {
		values.Set("start", "0")
	}

	if end != "" {
		values.Set("end", end)
	} else {
		values.Set("end", strconv.FormatInt(time.Now().Unix(), 10))
	}

	err := p.SendAuthenticatedHTTPRequest("POST", POLONIEX_DEPOSITS_WITHDRAWALS, values, &resp)

	if err != nil {
		return resp, err
	}

	return resp, nil
}

func (p *Poloniex) SendAuthenticatedHTTPRequest(method, endpoint string, values url.Values, result interface{}) error {
	headers := make(map[string]string)
	headers["Content-Type"] = "application/x-www-form-urlencoded"
	headers["Key"] = p.AccessKey

	nonce := time.Now().UnixNano()
	nonceStr := strconv.FormatInt(nonce, 10)

	values.Set("nonce", nonceStr)
	values.Set("command", endpoint)

	hmac := GetHMAC(HASH_SHA512, []byte(values.Encode()), []byte(p.SecretKey))
	headers["Sign"] = HexEncodeToString(hmac)

	path := fmt.Sprintf("%s/%s", POLONIEX_API_URL, POLONIEX_API_TRADING_ENDPOINT)
	resp, err := SendHTTPRequest(method, path, headers, bytes.NewBufferString(values.Encode()))

	if err != nil {
		return err
	}

	err = JSONDecode([]byte(resp), &result)

	if err != nil {
		return errors.New("Unable to JSON Unmarshal response.")
	}
	return nil
}