import { fetchAsync, logUtils } from '@0x/utils';

const PARADEX_BASE_URL = 'https://api.paradex.io/consumer/v0';
const ACTIVE_MARKETS_URL = PARADEX_BASE_URL + '/markets';
const ORDERBOOK_ENDPOINT = PARADEX_BASE_URL + '/orderbook';
const TOKEN_INFO_ENDPOINT = PARADEX_BASE_URL + '/tokens';
export const PARADEX_SOURCE = 'paradex';

export type ParadexActiveMarketsResponse = ParadexMarket[];

export interface ParadexMarket {
    id: string;
    symbol: string;
    baseToken: string;
    quoteToken: string;
    minOrderSize: string;
    maxOrderSize: string;
    priceMaxDecimals: number;
    amountMaxDecimals: number;
    // These are not native to the Paradex API response. We tag them on later
    // by calling the token endpoint and joining on symbol.
    baseTokenAddress?: string;
    quoteTokenAddress?: string;
}

export interface ParadexOrderbookResponse {
    marketId: number;
    marketSymbol: string;
    bids: ParadexOrder[];
    asks: ParadexOrder[];
}

export interface ParadexOrder {
    amount: string;
    price: string;
}

export type ParadexTokenInfoResponse = ParadexTokenInfo[];

export interface ParadexTokenInfo {
    name: string;
    symbol: string;
    address: string;
}

export class ParadexSource {
    private readonly _apiKey: string;

    constructor(apiKey: string) {
        this._apiKey = apiKey;
    }

    /**
     * Call Paradex API to find out which markets they are maintaining orderbooks for.
     */
    public async getActiveMarketsAsync(): Promise<ParadexActiveMarketsResponse> {
        logUtils.log('Getting all active Paradex markets.');
        const resp = await fetchAsync(ACTIVE_MARKETS_URL, {
            headers: { 'API-KEY': this._apiKey },
        });
        const markets: ParadexActiveMarketsResponse = await resp.json();
        logUtils.log(`Got ${markets.length} markets.`);
        return markets;
    }

    /**
     * Call Paradex API to find out their token information.
     */
    public async getTokenInfoAsync(): Promise<ParadexTokenInfoResponse> {
        logUtils.log('Getting token information from Paradex.');
        const resp = await fetchAsync(TOKEN_INFO_ENDPOINT, {
            headers: { 'API-KEY': this._apiKey },
        });
        const tokens: ParadexTokenInfoResponse = await resp.json();
        logUtils.log(`Got information for ${tokens.length} tokens.`);
        return tokens;
    }

    /**
     * Retrieve orderbook from Paradex API for a given market.
     * @param marketSymbol String representing the market we want data for.
     */
    public async getMarketOrderbookAsync(marketSymbol: string): Promise<ParadexOrderbookResponse> {
        logUtils.log(`${marketSymbol}: Retrieving orderbook.`);
        const marketOrderbookUrl = `${ORDERBOOK_ENDPOINT}?market=${marketSymbol}`;
        const resp = await fetchAsync(marketOrderbookUrl, {
            headers: { 'API-KEY': this._apiKey },
        });
        const orderbookResponse: ParadexOrderbookResponse = await resp.json();
        return orderbookResponse;
    }
}