using System.Net.Http.Json;
using System.Text.Json;
using Gateway.Models;

namespace Gateway.ProviderClients;

public sealed class GoogleProviderClient
{
    private readonly HttpClient _http;
    private readonly IConfiguration _config;
    private readonly ILogger<GoogleProviderClient> _logger;

    public GoogleProviderClient(HttpClient http, IConfiguration config, ILogger<GoogleProviderClient> logger)
    {
        _http = http;
        _config = config;
        _logger = logger;
    }

    private string GetInternalKey()
        => _config["Provider:Google:InternalKey"] 
           ?? Environment.GetEnvironmentVariable("GOOGLE_INTERNAL_KEY") 
           ?? "";

    public async Task<(int status, ProviderResponse body)> ExecuteAsync(ProviderRequest req, CancellationToken ct)
    {
        var key = GetInternalKey();
        if (string.IsNullOrWhiteSpace(key))
            return (500, new ProviderResponse { Ok = false, RequestId = req.RequestId, Error = new ProviderError { Code = "CONFIG", Message = "Missing Google internal key" } });

        using var msg = new HttpRequestMessage(HttpMethod.Post, "internal/execute");
        msg.Headers.Add("X-Internal-Key", key);
        msg.Content = JsonContent.Create(req, options: new JsonSerializerOptions(JsonSerializerDefaults.Web));

        var res = await _http.SendAsync(msg, ct);

        ProviderResponse? body = null;
        try
        {
            body = await res.Content.ReadFromJsonAsync<ProviderResponse>(cancellationToken: ct);
        }
        catch (Exception ex)
        {
            _logger.LogWarning(ex, "Failed to parse provider response as JSON");
        }

        body ??= new ProviderResponse
        {
            Ok = res.IsSuccessStatusCode,
            RequestId = req.RequestId,
            Error = res.IsSuccessStatusCode ? null : new ProviderError { Code = "PROVIDER", Message = "Non-JSON error from provider" }
        };

        // If provider returned a 4xx/5xx but body says Ok=true, normalize
        if (!res.IsSuccessStatusCode && body.Ok)
            body.Ok = false;

        return ((int)res.StatusCode, body);
    }
}