MTWorkHR/MTWorkHR.Application/Services/Payment/AmazonPayService.cs

using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Extensions.Configuration;
using MTWorkHR.Application.Services.Interfaces;
using Newtonsoft.Json;

public class AmazonPayService: IAmazonPayService
{
    private readonly HttpClient _httpClient;
    private readonly string _merchantId;
    private readonly string _accessKey;
    private readonly string _secretKey;
    private readonly string _region;
    private readonly bool _sandbox;

    public AmazonPayService(IConfiguration configuration, HttpClient httpClient)
    {
        _httpClient = httpClient;
        _merchantId = configuration["AmazonPay:MerchantId"];
        _accessKey = configuration["AmazonPay:AccessKey"];
        _secretKey = configuration["AmazonPay:SecretKey"];
        _region = configuration["AmazonPay:Region"];
        _sandbox = configuration.GetValue<bool>("AmazonPay:Sandbox");
    }

    public async Task<string> CreateCheckoutSessionAsync(decimal amount, string currencyCode)
    {
        var baseUrl = _sandbox ? "https://pay-api.amazon.com/sandbox" : "https://pay-api.amazon.com";
        var endpoint = $"{baseUrl}/{_region}/checkout-sessions";

        var payload = new
        {
            checkoutReviewReturnUrl = "https://yourwebsite.com/review",
            checkoutResultReturnUrl = "https://yourwebsite.com/result",
            chargeAmount = new
            {
                amount = amount.ToString("F2"),
                currencyCode = currencyCode
            },
            merchantMetadata = new
            {
                merchantReferenceId = Guid.NewGuid().ToString(),
                merchantStoreName = "Your Store Name"
            }
        };

        var content = new StringContent(JsonConvert.SerializeObject(payload), Encoding.UTF8, "application/json");

        // Add required headers
        _httpClient.DefaultRequestHeaders.Clear();
        _httpClient.DefaultRequestHeaders.Add("x-amz-pay-idempotency-key", Guid.NewGuid().ToString());
        _httpClient.DefaultRequestHeaders.Add("x-amz-pay-authtoken", GenerateAuthToken());

        var response = await _httpClient.PostAsync(endpoint, content);
        response.EnsureSuccessStatusCode();

        var responseBody = await response.Content.ReadAsStringAsync();
        return responseBody;
    }

    private string GenerateAuthToken()
    {
        // Implement Amazon Pay's signature calculation logic here.
        // Refer to Amazon Pay's documentation for details: https://developer.amazon.com/docs/amazon-pay-api/signature.html
        return "YOUR_AUTH_TOKEN";
    }
}