using System.Net.Http;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace JobTrackerApi.Services;

public sealed record CvNormalizationResult(
    double? Confidence,
    string? Reason,
    [property: JsonPropertyName("normalized_text")] string? NormalizedText);

public interface ICvAiNormalizer
{
    Task<CvNormalizationResult?> NormalizeAsync(string text, CancellationToken cancellationToken = default);
}

public sealed class CvAiNormalizer : ICvAiNormalizer
{
    private readonly IHttpClientFactory _httpClientFactory;

    public CvAiNormalizer(IHttpClientFactory httpClientFactory)
    {
        _httpClientFactory = httpClientFactory;
    }

    public async Task<CvNormalizationResult?> NormalizeAsync(string text, CancellationToken cancellationToken = default)
    {
        if (string.IsNullOrWhiteSpace(text)) return null;

        try
        {
            var client = _httpClientFactory.CreateClient("ai-service");
            var payload = JsonSerializer.Serialize(new { text });
            using var content = new StringContent(payload, Encoding.UTF8, "application/json");
            using var response = await client.PostAsync("/cv/normalize", content, cancellationToken);
            if (!response.IsSuccessStatusCode) return null;

            await using var stream = await response.Content.ReadAsStreamAsync(cancellationToken);
            return await JsonSerializer.DeserializeAsync<CvNormalizationResult>(stream, new JsonSerializerOptions(JsonSerializerDefaults.Web)
            {
                PropertyNameCaseInsensitive = true
            }, cancellationToken);
        }
        catch
        {
            return null;
        }
    }
}

public sealed class NoOpCvAiNormalizer : ICvAiNormalizer
{
    public static NoOpCvAiNormalizer Instance { get; } = new();
    private NoOpCvAiNormalizer() { }
    public Task<CvNormalizationResult?> NormalizeAsync(string text, CancellationToken cancellationToken = default)
        => Task.FromResult<CvNormalizationResult?>(null);
}