#pragma warning disable OPENAI001
using OpenAI.Responses;
using System.ClientModel;

namespace Intendant.Shared.Services;

public sealed class OpenAiResponsesService : IOpenAiResponsesService
{
    private readonly IOpenAiSettingsService _settingsService;

    public OpenAiResponsesService(IOpenAiSettingsService settingsService)
    {
        _settingsService = settingsService;
    }

    public async Task<string> GenerateTextAsync(string prompt, CancellationToken cancellationToken = default)
    {
        if (string.IsNullOrWhiteSpace(prompt))
        {
            throw new ArgumentException("Le prompt ne peut pas être vide.", nameof(prompt));
        }

        OpenAiResponsesOptions settings = await _settingsService.GetAsync(cancellationToken);

        string apiKey = settings.ApiKey?.Trim() ?? string.Empty;
        if (string.IsNullOrWhiteSpace(apiKey))
        {
            throw new InvalidOperationException("La clé API OpenAI est requise pour appeler la Responses API.");
        }

        string model = string.IsNullOrWhiteSpace(settings.Model)
            ? "gpt-5-mini"
            : settings.Model;

        ResponsesClient client = CreateClient(apiKey, settings.Endpoint);

        CreateResponseOptions options = new()
        {
            Model = model,
        };

        options.InputItems.Add(ResponseItem.CreateUserMessageItem(prompt));

        ResponseResult response = await client.CreateResponseAsync(options, cancellationToken);

        string text = string.Join(
            Environment.NewLine,
            response.OutputItems
                .OfType<MessageResponseItem>()
                .SelectMany(message => message.Content)
                .Select(content => content.Text)
                .Where(value => !string.IsNullOrWhiteSpace(value)));

        return text;
    }

    private static ResponsesClient CreateClient(string apiKey, string endpoint)
    {
        if (string.IsNullOrWhiteSpace(endpoint))
        {
            return new ResponsesClient(apiKey);
        }

        if (!Uri.TryCreate(endpoint, UriKind.Absolute, out Uri? endpointUri))
        {
            throw new InvalidOperationException("L'endpoint OpenAI configuré est invalide.");
        }

        ResponsesClientOptions clientOptions = new()
        {
            Endpoint = endpointUri,
        };

        return new ResponsesClient(new ApiKeyCredential(apiKey), clientOptions);
    }
}
#pragma warning restore OPENAI001