using FastEndpoints;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.DTO.Framework.ResponseStandard;
using GB5Shared.FastEndPoint;
using PayRollBLL.SAP;
using System;
using System.Text.Json;
using System.Threading;
using System.Threading.Tasks;
using static GB5Shared.GB5Constant.Constant;

namespace PayRollSL.EndPoints.SAP
{
    /// <summary>
    /// GET /SAP/GetITDeclarationJson
    /// Returns SAP infotype JSON payloads as a dictionary (infotype → JSON string).
    /// Supports single-declaration or bulk (by EmployeeId / PeriodId) modes.
    /// Pass Infotype=0 to generate all infotypes 580–586.
    /// </summary>
    public class GetITDeclarationJson
        : BaseEndpoint<GetITDeclarationJson.GetITDeclarationJsonParameters, ResponseStandardDTO<object>>
    {
        private readonly IITDeclarationSapBLL _bll;

        public GetITDeclarationJson(IITDeclarationSapBLL bll) => _bll = bll;

        public override void Configure()
        {
            Get("/SAP/GetITDeclarationJson");
            AllowAnonymous();
        }

        public record GetITDeclarationJsonParameters(
            [property: FromHeader] string Login,
            [property: QueryParam] int DeclarationId,
            [property: QueryParam] int EmployeeId,
            [property: QueryParam] int PeriodId,
            [property: QueryParam] int Infotype,       // 0 = all 580–586
            [property: QueryParam] string? Date,       // dd.MM.yyyy; defaults to today
            [property: QueryParam] string? Remarks
        );

        // No cache — SAP payloads should always reflect the latest approved data
        protected override string? GetCacheKey(GetITDeclarationJsonParameters req, LoginDTO login) => null;

        protected override async Task<ResponseStandardDTO<object>> ExecuteAsync(
            GetITDeclarationJsonParameters req,
            LoginDTO login,
            CancellationToken ct)
        {
            string date = string.IsNullOrWhiteSpace(req.Date)
                ? DateTime.Today.ToString("dd.MM.yyyy")
                : req.Date;

            var payloads = await _bll.GenerateSapPayloadsAsync(
                req.DeclarationId,
                req.EmployeeId,
                req.PeriodId,
                req.Infotype,
                date,
                req.Remarks ?? string.Empty,
                login,
                ct);

            // Parse each JSON string to JsonElement so the response contains
            // proper nested JSON objects, not escaped string values.
            var result = payloads.ToDictionary(
                kvp => kvp.Key,
                kvp => JsonDocument.Parse(kvp.Value).RootElement.Clone());

            return await GB5Shared.ResponseStandard.Response
                .CreateSuccessResponse(result, CacheKeyLevel.NOT_REQUIRED, login);
        }
    }
}