using System.Linq;
using AccountsBLL.AccountReports.AccountBudgetVsComparison;
using AccountsDAL.DTO.AccountsReports;
using FastEndpoints;
using GB5Shared.DTO.Framework.Criteria;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.DTO.Report;
using GB5Shared.FastEndPoint;

namespace AccountsSL.EndPoints.AccountReports
{
    // Budget vs Actual Comparison (Finance Dashboard Migration Phase 2) -- BudgetId/ComparisonType
    // read directly from CriteriaDTO, same "dedicated criteria field, not a bespoke request shape"
    // convention as AccountProfitLossDashboardReport's own DashboardPeriodType field. Small, bounded
    // result set (one row per budget line, or per OU for the rollup) -- ExecutePagedAsync overridden
    // to return the full list directly, same pattern as every other dashboard this session.
    public class AccountBudgetVsComparisonReport
        : BaseReportEndpoint<AccountBudgetVsComparisonReport.AccountBudgetVsComparisonReportParameter, BudgetVsComparisonDTO>
    {
        private readonly IAccountBudgetVsComparisonReportBLL _bll;

        public AccountBudgetVsComparisonReport(IAccountBudgetVsComparisonReportBLL bll)
        {
            _bll = bll;
        }

        public override void Configure()
        {
            Post("/AccountReports/AccountBudgetVsComparisonReport");
            AllowAnonymous();
        }

        public record AccountBudgetVsComparisonReportParameter(
            [property: FromHeader] string Login,
            [property: FromBody] ReportCallingDTO ReportCallingDTO
        );

        // ViewLevel/OuAxis/AccountNature only matter for ComparisonType=1 (the pivot) -- see
        // AccountBudgetVsComparisonReportDAL's OuAxisMap/ViewLevelMap for what each value selects.
        // ViewLevel: 0=Account,2=AccountGroup,3=AccountScheduleNature,4=AccountGroupNature,9=Overall.
        // OuAxis (legacy "SubType"/"outype"): 0=OU,1=Company,2=Branch,3=Division,9=Overall.
        // AccountNature: 0=All,1=P&L (schedule nature not in Asset/Liability),2=BS (Asset/Liability only).
        private static (int BudgetId, byte ComparisonType, byte ViewLevel, byte OuAxis, byte AccountNature, List<int>? OuIds, int OuGroupId) ParseParams(CriteriaDTO? criteriaDTO)
        {
            int budgetId = 0;
            byte comparisonType = 0;
            byte viewLevel = 0;
            byte ouAxis = 0;
            byte accountNature = 0;
            List<int>? ouIds = null;
            int ouGroupId = -1;
            if (criteriaDTO?.SectionCriteriaList == null) return (budgetId, comparisonType, viewLevel, ouAxis, accountNature, ouIds, ouGroupId);

            foreach (var section in criteriaDTO.SectionCriteriaList)
            {
                if (section.AttributesCriteriaList == null) continue;
                foreach (var attr in section.AttributesCriteriaList)
                {
                    var field = attr.FieldName?.ToLowerInvariant();
                    if (field == "budgetid" && int.TryParse(attr.FieldValue?.ToString(), out var bId))
                        budgetId = bId;
                    else if (field == "comparisontype" && byte.TryParse(attr.FieldValue?.ToString(), out var cType))
                        comparisonType = cType;
                    else if (field == "viewlevel" && byte.TryParse(attr.FieldValue?.ToString(), out var vLevel))
                        viewLevel = vLevel;
                    else if (field == "ouaxis" && byte.TryParse(attr.FieldValue?.ToString(), out var oAxis))
                        ouAxis = oAxis;
                    else if (field == "accountnature" && byte.TryParse(attr.FieldValue?.ToString(), out var aNature))
                        accountNature = aNature;
                    else if (field == "ouid" && attr.FieldValue != null)
                        ouIds = attr.FieldValue.ToString()?.Split(',', StringSplitOptions.RemoveEmptyEntries)
                            .Select(s => int.TryParse(s.Trim(), out var v) ? v : 0).Where(v => v != 0).ToList();
                    else if (field == "ougroupid" && int.TryParse(attr.FieldValue?.ToString(), out var gId))
                        ouGroupId = gId;
                }
            }
            return (budgetId, comparisonType, viewLevel, ouAxis, accountNature, ouIds, ouGroupId);
        }

        protected override async IAsyncEnumerable<BudgetVsComparisonDTO> ExecuteReportAsync(
            AccountBudgetVsComparisonReportParameter req, LoginDTO login,
            [System.Runtime.CompilerServices.EnumeratorCancellation] CancellationToken ct)
        {
            var (budgetId, comparisonType, viewLevel, ouAxis, accountNature, ouIds, ouGroupId) = ParseParams(req.ReportCallingDTO.CriteriaDTO);
            var result = await _bll.GetBudgetVsComparisonReport(budgetId, comparisonType, viewLevel, ouAxis, accountNature, ouIds, ouGroupId, login, ct).ConfigureAwait(false);
            foreach (var row in result)
            {
                ct.ThrowIfCancellationRequested();
                yield return row;
            }
        }

        protected override async Task<GB5Shared.DTO.Framework.ResponseStandard.ResponseStandardDTO<object>> ExecutePagedAsync(
            AccountBudgetVsComparisonReportParameter req, LoginDTO login, CancellationToken ct)
        {
            try
            {
                var (budgetId, comparisonType, viewLevel, ouAxis, accountNature, ouIds, ouGroupId) = ParseParams(req.ReportCallingDTO.CriteriaDTO);
                var result = await _bll.GetBudgetVsComparisonReport(budgetId, comparisonType, viewLevel, ouAxis, accountNature, ouIds, ouGroupId, login, ct).ConfigureAwait(false);
                return await GB5Shared.ResponseStandard.Response.CreateSuccessResponse(
                    result, GB5Shared.GB5Constant.Constant.CacheKeyLevel.NOT_REQUIRED, login);
            }
            catch (Exception ex)
            {
                return await GB5Shared.ResponseStandard.Response.CreateExceptionError<string>(
                    ex, GB5Shared.GB5Constant.Constant.CacheKeyLevel.NOT_REQUIRED, login, ex.Message, 500);
            }
        }
    }
}