using System.Net.Http.Json;
using System.Text.Json;
using GB5Shared.DTO.Framework.Login;
using Microsoft.Extensions.Logging;

namespace DXPBLL.VendorPo;

public class MmIntegrationService : IMmIntegrationService
{
    private readonly IHttpClientFactory _HttpClientFactory;
    private readonly ILogger<MmIntegrationService> _Logger;

    public MmIntegrationService(IHttpClientFactory httpClientFactory, ILogger<MmIntegrationService> logger)
    {
        _HttpClientFactory = httpClientFactory;
        _Logger            = logger;
    }

    public async Task<StockReservationOutcome> TriggerAutoReservationAsync(
        StockReservationRequestDTO request, LoginDTO tenantLogin, CancellationToken ct)
    {
        try
        {
            var client = _HttpClientFactory.CreateClient("MMModule");
            client.DefaultRequestHeaders.Remove("Login");
            client.DefaultRequestHeaders.Add("Login", JsonSerializer.Serialize(tenantLogin));

            var response = await client.PostAsJsonAsync("StockReservation/SaveStockReservation", request, ct)
                .ConfigureAwait(false);

            if (!response.IsSuccessStatusCode)
            {
                var body = await response.Content.ReadAsStringAsync(ct).ConfigureAwait(false);
                _Logger.LogWarning(
                    "MM SaveStockReservation returned {StatusCode} for LinkedPoId {LinkedPoId}: {Body}",
                    response.StatusCode, request.LinkedPoId, body);
                return new StockReservationOutcome { Success = false, Error = $"MM returned {(int)response.StatusCode}" };
            }

            // MM's own ResponseStandardDTO wraps the actual reservation id in .Body — read it
            // permissively (a reservation succeeding is what matters for Phase 1.3; a follow-up
            // phase should parse MM's exact Body shape once its ExecuteSaveAsync return
            // convention is confirmed against a live MM instance, see Part 4/1.7 of the plan).
            var raw = await response.Content.ReadAsStringAsync(ct).ConfigureAwait(false);
            return new StockReservationOutcome { Success = true, Error = null, ReservationId = TryExtractId(raw) };
        }
        catch (Exception ex)
        {
            _Logger.LogError(ex, "MM SaveStockReservation call failed for LinkedPoId {LinkedPoId}", request.LinkedPoId);
            return new StockReservationOutcome { Success = false, Error = ex.Message };
        }
    }

    private static int? TryExtractId(string rawJson)
    {
        try
        {
            using var doc = JsonDocument.Parse(rawJson);
            if (doc.RootElement.TryGetProperty("Body", out var body) && body.ValueKind == JsonValueKind.Number)
                return body.GetInt32();
        }
        catch { /* best effort — reservation still succeeded even if we can't parse the id */ }
        return null;
    }

    public async Task<MmDocumentSaveOutcome> SaveMmDocumentAsync(
        MmDocumentSaveRequestDTO request, LoginDTO tenantLogin, CancellationToken ct)
    {
        try
        {
            var client = _HttpClientFactory.CreateClient("MMModule");
            client.DefaultRequestHeaders.Remove("Login");
            client.DefaultRequestHeaders.Add("Login", JsonSerializer.Serialize(tenantLogin));

            var response = await client.PostAsJsonAsync("MMHead/SaveMMHead", request, ct)
                .ConfigureAwait(false);

            if (!response.IsSuccessStatusCode)
            {
                var body = await response.Content.ReadAsStringAsync(ct).ConfigureAwait(false);
                _Logger.LogWarning(
                    "MM SaveMMHead returned {StatusCode} for BizTransactionTypeId {BizTransactionTypeId}: {Body}",
                    response.StatusCode, request.BizTransactionTypeId, body);
                return new MmDocumentSaveOutcome { Success = false, Error = $"MM returned {(int)response.StatusCode}: {body}" };
            }

            return new MmDocumentSaveOutcome { Success = true };
        }
        catch (Exception ex)
        {
            _Logger.LogError(ex, "MM SaveMMHead call failed for BizTransactionTypeId {BizTransactionTypeId}", request.BizTransactionTypeId);
            return new MmDocumentSaveOutcome { Success = false, Error = ex.Message };
        }
    }
}