AssetManager.API/AssetManager.Infrastructure/Services/OkxMarketService.cs

using System.Net.Http.Json;
using AssetManager.Models.DTOs;
using Microsoft.Extensions.Logging;

namespace AssetManager.Infrastructure.Services;

/// <summary>
/// OKX 加密货币市场数据服务接口
/// </summary>
public interface IOkxMarketService
{
    /// <summary>
    /// 获取加密货币实时价格
    /// </summary>
    Task<MarketPriceResponse> GetCryptoPriceAsync(string symbol);
    
    /// <summary>
    /// 获取加密货币历史K线数据
    /// </summary>
    Task<List<MarketDataResponse>> GetCryptoHistoricalDataAsync(string symbol, string timeframe, int limit);
}

/// <summary>
/// OKX 加密货币市场数据服务实现
/// </summary>
public class OkxMarketService : IOkxMarketService
{
    private readonly ILogger<OkxMarketService> _logger;
    private readonly HttpClient _httpClient;

    public OkxMarketService(ILogger<OkxMarketService> logger, IHttpClientFactory httpClientFactory)
    {
        _logger = logger;
        _httpClient = httpClientFactory.CreateClient();
    }

    public async Task<MarketPriceResponse> GetCryptoPriceAsync(string symbol)
    {
        _logger.LogInformation("OKX 获取加密货币价格: {Symbol}", symbol);

        // OKX 实时 ticker 接口，symbol 格式如 BTC-USDT
        var url = $"https://www.okx.com/api/v5/market/ticker?instId={symbol}";
        var response = await _httpClient.GetFromJsonAsync<OkxTickerResponse>(url);

        if (response == null || response.code != "0" || response.data == null || response.data.Count == 0)
        {
            throw new Exception($"No data found for {symbol}, code: {response?.code}, msg: {response?.msg}");
        }

        var latest = response.data[0];
        return new MarketPriceResponse
        {
            Symbol = symbol,
            Price = decimal.TryParse(latest.last, out var price) ? price : 0,
            PreviousClose = decimal.TryParse(latest.sodUtc0, out var prevClose) ? prevClose : 0,
            Timestamp = DateTime.UtcNow,
            AssetType = "Crypto"
        };
    }

    public async Task<List<MarketDataResponse>> GetCryptoHistoricalDataAsync(string symbol, string timeframe, int limit)
    {
        _logger.LogInformation("OKX 获取历史数据: {Symbol}, 周期: {Timeframe}, 数量: {Limit}", symbol, timeframe, limit);

        // 转换 timeframe 为 OKX 支持的粒度
        var bar = ConvertToOkxBar(timeframe);
        
        // OKX K线接口
        var url = $"https://www.okx.com/api/v5/market/candles?instId={symbol}&bar={bar}&limit={limit}";
        var response = await _httpClient.GetFromJsonAsync<OkxCandlesResponse>(url);

        if (response == null || response.code != "0" || response.data == null)
        {
            throw new Exception($"No data found for {symbol}, code: {response?.code}, msg: {response?.msg}");
        }

        var result = new List<MarketDataResponse>();
        foreach (var item in response.data)
        {
            if (item.Length < 6) continue;

            if (long.TryParse(item[0], out var ts) &&
                decimal.TryParse(item[1], out var open) &&
                decimal.TryParse(item[2], out var high) &&
                decimal.TryParse(item[3], out var low) &&
                decimal.TryParse(item[4], out var close) &&
                decimal.TryParse(item[5], out var volume))
            {
                result.Add(new MarketDataResponse
                {
                    Symbol = symbol,
                    Open = open,
                    High = high,
                    Low = low,
                    Close = close,
                    Volume = volume,
                    Timestamp = DateTimeOffset.FromUnixTimeMilliseconds(ts).UtcDateTime,
                    AssetType = "Crypto"
                });
            }
        }

        // 按时间升序排列
        return result.OrderBy(x => x.Timestamp).ToList();
    }

    private string ConvertToOkxBar(string timeframe)
    {
        return timeframe.ToLower() switch
        {
            "1min" => "1m",
            "5min" => "5m",
            "15min" => "15m",
            "1h" => "1H",
            "4h" => "4H",
            "1d" => "1D",
            "1w" => "1W",
            "1m" => "1M",
            _ => "1D"
        };
    }
}

// OKX 响应模型
internal class OkxTickerResponse
{
    public string code { get; set; }
    public string msg { get; set; }
    public List<OkxTickerData> data { get; set; }
}

internal class OkxTickerData
{
    public string instId { get; set; }
    public string last { get; set; }
    public string sodUtc0 { get; set; }
}

internal class OkxCandlesResponse
{
    public string code { get; set; }
    public string msg { get; set; }
    public List<string[]> data { get; set; }
}