package anx

import (
	"bytes"
	"errors"
	"fmt"
	"net/http"
	"strconv"
	"time"

	"github.com/thrasher-corp/gocryptotrader/common"
	"github.com/thrasher-corp/gocryptotrader/common/crypto"
	"github.com/thrasher-corp/gocryptotrader/currency"
	exchange "github.com/thrasher-corp/gocryptotrader/exchanges"
	log "github.com/thrasher-corp/gocryptotrader/logger"
)

const (
	anxAPIURL          = "https://anxpro.com/"
	anxAPIVersion      = "3"
	anxAPIKey          = "apiKey"
	anxCurrencies      = "currencyStatic"
	anxDataToken       = "dataToken"
	anxOrderNew        = "order/new"
	anxOrderCancel     = "order/cancel"
	anxOrderList       = "order/list"
	anxOrderInfo       = "order/info"
	anxSend            = "send"
	anxSubaccountNew   = "subaccount/new"
	anxReceieveAddress = "receive"
	anxCreateAddress   = "receive/create"
	anxTicker          = "money/ticker"
	anxDepth           = "money/depth/full"
	anxAccount         = "account"

	// ANX rate limites for authenticated and unauthenticated requests
	anxAuthRate   = 0
	anxUnauthRate = 0
)

// ANX is the overarching type across the alphapoint package
type ANX struct {
	exchange.Base
}

// GetCurrencies returns a list of supported currencies (both fiat
// and cryptocurrencies)
func (a *ANX) GetCurrencies() (CurrenciesStore, error) {
	var result CurrenciesStaticResponse
	path := fmt.Sprintf("%sapi/3/%s", a.API.Endpoints.URL, anxCurrencies)

	err := a.SendHTTPRequest(path, &result)
	if err != nil {
		return CurrenciesStore{}, err
	}

	return result.CurrenciesResponse, nil
}

// GetTicker returns the current ticker
func (a *ANX) GetTicker(currency string) (Ticker, error) {
	var t Ticker
	path := fmt.Sprintf("%sapi/2/%s/%s", a.API.Endpoints.URL, currency, anxTicker)
	return t, a.SendHTTPRequest(path, &t)
}

// GetDepth returns current orderbook depth.
func (a *ANX) GetDepth(currency string) (Depth, error) {
	var depth Depth
	path := fmt.Sprintf("%sapi/2/%s/%s", a.API.Endpoints.URL, currency, anxDepth)
	return depth, a.SendHTTPRequest(path, &depth)
}

// GetAPIKey returns a new generated API key set.
func (a *ANX) GetAPIKey(username, password, otp, deviceID string) (apiKey, apiSecret string, err error) {
	req := make(map[string]interface{})
	req["nonce"] = strconv.FormatInt(time.Now().UnixNano(), 10)[0:13]
	req["username"] = username
	req["password"] = password

	if otp != "" {
		req["otp"] = otp
	}

	req["deviceId"] = deviceID

	type APIKeyResponse struct {
		APIKey     string `json:"apiKey"`
		APISecret  string `json:"apiSecret"`
		ResultCode string `json:"resultCode"`
		Timestamp  int64  `json:"timestamp"`
	}
	var response APIKeyResponse

	err = a.SendAuthenticatedHTTPRequest(anxAPIKey, req, &response)
	if err != nil {
		return apiKey, apiSecret, err
	}

	if response.ResultCode != "OK" {
		return apiKey, apiSecret, errors.New("Response code is not OK: " + response.ResultCode)
	}

	apiKey = response.APIKey
	apiSecret = response.APISecret
	return apiKey, apiSecret, err
}

// GetDataToken returns token data
func (a *ANX) GetDataToken() (string, error) {
	req := make(map[string]interface{})

	type DataTokenResponse struct {
		ResultCode string `json:"resultCode"`
		Timestamp  int64  `json:"timestamp"`
		Token      string `json:"token"`
		UUID       string `json:"uuid"`
	}
	var response DataTokenResponse

	err := a.SendAuthenticatedHTTPRequest(anxDataToken, req, &response)
	if err != nil {
		return "", err
	}

	if response.ResultCode != "OK" {
		return "", errors.New("Response code is not OK: %s" + response.ResultCode)
	}
	return response.Token, nil
}

// NewOrder sends a new order request to the exchange.
func (a *ANX) NewOrder(orderType string, buy bool, tradedCurrency string, tradedCurrencyAmount float64, settlementCurrency string, settlementCurrencyAmount, limitPriceSettlement float64,
	replace bool, replaceUUID string, replaceIfActive bool) (string, error) {

	req := make(map[string]interface{})
	var order Order
	order.OrderType = orderType
	order.BuyTradedCurrency = buy

	if buy {
		order.TradedCurrencyAmount = tradedCurrencyAmount
	} else {
		order.SettlementCurrencyAmount = settlementCurrencyAmount
	}

	order.TradedCurrency = tradedCurrency
	order.SettlementCurrency = settlementCurrency
	order.LimitPriceInSettlementCurrency = limitPriceSettlement

	if replace {
		order.ReplaceExistingOrderUUID = replaceUUID
		order.ReplaceOnlyIfActive = replaceIfActive
	}

	req["order"] = order

	type OrderResponse struct {
		OrderID    string `json:"orderId"`
		Timestamp  int64  `json:"timestamp,string"`
		ResultCode string `json:"resultCode"`
	}
	var response OrderResponse

	err := a.SendAuthenticatedHTTPRequest(anxOrderNew, req, &response)
	if err != nil {
		return "", err
	}

	if response.ResultCode != "OK" {
		return "", errors.New("Response code is not OK: " + response.ResultCode)
	}
	return response.OrderID, nil
}

// CancelOrderByIDs cancels orders, requires already knowing order IDs
// There is no existing API call to retrieve orderIds
func (a *ANX) CancelOrderByIDs(orderIds []string) (OrderCancelResponse, error) {
	var response OrderCancelResponse
	if len(orderIds) == 0 {
		return response, errors.New("no order ids provided")
	}

	req := make(map[string]interface{})
	req["orderIds"] = orderIds

	err := a.SendAuthenticatedHTTPRequest(anxOrderCancel, req, &response)
	if response.ResultCode != "OK" {
		return response, errors.New(response.ResultCode)
	}

	return response, err
}

// GetOrderList retrieves orders from the exchange
func (a *ANX) GetOrderList(isActiveOrdersOnly bool) ([]OrderResponse, error) {
	req := make(map[string]interface{})
	req["activeOnly"] = isActiveOrdersOnly

	type OrderListResponse struct {
		Timestamp      int64           `json:"timestamp,string"`
		ResultCode     string          `json:"resultCode"`
		Count          int64           `json:"count"`
		OrderResponses []OrderResponse `json:"orders"`
	}
	var response OrderListResponse
	err := a.SendAuthenticatedHTTPRequest(anxOrderList, req, &response)
	if err != nil {
		return nil, err
	}

	if response.ResultCode != "OK" {
		return nil, errors.New(response.ResultCode)
	}

	return response.OrderResponses, err
}

// OrderInfo returns information about a specific order
func (a *ANX) OrderInfo(orderID string) (OrderResponse, error) {
	req := make(map[string]interface{})
	req["orderId"] = orderID

	type OrderInfoResponse struct {
		Order      OrderResponse `json:"order"`
		ResultCode string        `json:"resultCode"`
		Timestamp  int64         `json:"timestamp"`
	}
	var response OrderInfoResponse

	err := a.SendAuthenticatedHTTPRequest(anxOrderInfo, req, &response)

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

	if response.ResultCode != "OK" {
		return OrderResponse{}, errors.New(response.ResultCode)
	}
	return response.Order, nil
}

// Send withdraws a currency to an address
func (a *ANX) Send(currency, address, otp, amount string) (string, error) {
	req := make(map[string]interface{})
	req["ccy"] = currency
	req["amount"] = amount
	req["address"] = address

	if otp != "" {
		req["otp"] = otp
	}

	type SendResponse struct {
		TransactionID string `json:"transactionId"`
		ResultCode    string `json:"resultCode"`
		Timestamp     int64  `json:"timestamp,string"`
	}
	var response SendResponse

	err := a.SendAuthenticatedHTTPRequest(anxSend, req, &response)

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

	if response.ResultCode != "OK" {
		return "", errors.New(response.ResultCode)
	}
	return response.TransactionID, nil
}

// CreateNewSubAccount generates a new sub account
func (a *ANX) CreateNewSubAccount(currency, name string) (string, error) {
	req := make(map[string]interface{})
	req["ccy"] = currency
	req["customRef"] = name

	type SubaccountResponse struct {
		SubAccount string `json:"subAccount"`
		ResultCode string `json:"resultCode"`
		Timestamp  int64  `json:"timestamp"`
	}
	var response SubaccountResponse

	err := a.SendAuthenticatedHTTPRequest(anxSubaccountNew, req, &response)

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

	if response.ResultCode != "OK" {
		return "", errors.New(response.ResultCode)
	}
	return response.SubAccount, nil
}

// GetDepositAddressByCurrency returns a deposit address for a specific currency
func (a *ANX) GetDepositAddressByCurrency(currency, name string, newAddr bool) (string, error) {
	req := make(map[string]interface{})
	req["ccy"] = currency

	if name != "" {
		req["subAccount"] = name
	}

	type AddressResponse struct {
		Address    string `json:"address"`
		SubAccount string `json:"subAccount"`
		ResultCode string `json:"resultCode"`
		Timestamp  int64  `json:"timestamp,string"`
	}
	var response AddressResponse

	path := anxReceieveAddress
	if newAddr {
		path = anxCreateAddress
	}

	err := a.SendAuthenticatedHTTPRequest(path, req, &response)
	if err != nil {
		return "", err
	}

	if response.ResultCode != "OK" {
		return "", errors.New(response.ResultCode)
	}

	return response.Address, nil
}

// SendHTTPRequest sends an unauthenticated HTTP request
func (a *ANX) SendHTTPRequest(path string, result interface{}) error {
	return a.SendPayload(http.MethodGet,
		path,
		nil,
		nil,
		result,
		false,
		false,
		a.Verbose,
		a.HTTPDebugging,
		a.HTTPRecording)
}

// SendAuthenticatedHTTPRequest sends a authenticated HTTP request
func (a *ANX) SendAuthenticatedHTTPRequest(path string, params map[string]interface{}, result interface{}) error {
	if !a.AllowAuthenticatedRequest() {
		return fmt.Errorf(exchange.WarningAuthenticatedRequestWithoutCredentialsSet, a.Name)
	}

	n := a.Requester.GetNonce(true)
	req := make(map[string]interface{})
	req["nonce"] = n.String()[0:13]
	path = fmt.Sprintf("api/%s/%s", anxAPIVersion, path)

	for key, value := range params {
		req[key] = value
	}

	PayloadJSON, err := common.JSONEncode(req)
	if err != nil {
		return errors.New("unable to JSON request")
	}

	if a.Verbose {
		log.Debugf(log.ExchangeSys, "Request JSON: %s\n", PayloadJSON)
	}

	hmac := crypto.GetHMAC(crypto.HashSHA512, []byte(path+string("\x00")+string(PayloadJSON)), []byte(a.API.Credentials.Secret))
	headers := make(map[string]string)
	headers["Rest-Key"] = a.API.Credentials.Key
	headers["Rest-Sign"] = crypto.Base64Encode(hmac)
	headers["Content-Type"] = "application/json"

	return a.SendPayload(http.MethodPost,
		a.API.Endpoints.URL+path,
		headers,
		bytes.NewBuffer(PayloadJSON),
		result,
		true,
		true,
		a.Verbose,
		a.HTTPDebugging,
		a.HTTPRecording)
}

// GetFee returns an estimate of fee based on type of transaction
func (a *ANX) GetFee(feeBuilder *exchange.FeeBuilder) (float64, error) {
	var fee float64

	switch feeBuilder.FeeType {
	case exchange.CryptocurrencyTradeFee:
		fee = a.calculateTradingFee(feeBuilder.PurchasePrice, feeBuilder.Amount, feeBuilder.IsMaker)
	case exchange.CryptocurrencyWithdrawalFee:
		fee = getCryptocurrencyWithdrawalFee(feeBuilder.Pair.Base)
	case exchange.InternationalBankWithdrawalFee:
		fee = getInternationalBankWithdrawalFee(feeBuilder.FiatCurrency, feeBuilder.Amount)
	case exchange.OfflineTradeFee:
		fee = getOfflineTradeFee(feeBuilder.PurchasePrice, feeBuilder.Amount)
	}
	if fee < 0 {
		fee = 0
	}
	return fee, nil
}

// getOfflineTradeFee calculates the worst case-scenario trading fee
func getOfflineTradeFee(price, amount float64) float64 {
	return 0.002 * price * amount
}

func (a *ANX) calculateTradingFee(purchasePrice, amount float64, isMaker bool) float64 {
	var fee float64

	if isMaker {
		fee = 0.01 * amount * purchasePrice
	} else {
		fee = 0.02 * amount * purchasePrice
	}

	return fee
}

func getCryptocurrencyWithdrawalFee(c currency.Code) float64 {
	return WithdrawalFees[c]
}

func getInternationalBankWithdrawalFee(c currency.Code, amount float64) float64 {
	var fee float64

	if c == currency.HKD {
		fee = 250 + (WithdrawalFees[c] * amount)
	}
	// TODO, other fiat currencies require consultation with ANXPRO
	return fee
}

// GetAccountInformation retrieves details including API permissions
func (a *ANX) GetAccountInformation() (AccountInformation, error) {
	var response AccountInformation
	err := a.SendAuthenticatedHTTPRequest(anxAccount, nil, &response)
	if err != nil {
		return response, err
	}

	if response.ResultCode != "OK" {
		log.Errorf(log.ExchangeSys, "Response code is not OK: %s\n", response.ResultCode)
		return response, errors.New(response.ResultCode)
	}
	return response, nil
}

// CheckAPIWithdrawPermission checks if the API key is allowed to withdraw
func (a *ANX) CheckAPIWithdrawPermission() (bool, error) {
	accountInfo, err := a.GetAccountInformation()

	if err != nil {
		return false, err
	}

	var apiAllowsWithdraw bool

	for _, a := range accountInfo.Rights {
		if a == "withdraw" {
			apiAllowsWithdraw = true
		}
	}

	if !apiAllowsWithdraw {
		log.Warn(log.ExchangeSys, "API key is missing withdrawal permissions")
	}

	return apiAllowsWithdraw, nil
}