// import { BadRequestException, Injectable, NotFoundException } from "@nestjs/common";
// import { LeaveApprovalStatus, LeaveTypes } from "@prisma/client";
// import { roundToQuarterHour } from "src/common/utils/date-utils";
// import { UpsertLeaveRequestDto, UpsertResult } from "../dtos/upsert-leave-request.dto";
// import { LeaveRequestViewDto } from "../dtos/leave-request-view.dto";
// import { mapRowToView } from "../mappers/leave-requests.mapper";
// import { leaveRequestsSelect } from "../utils/leave-requests.select";
// import { HolidayLeaveRequestsService } from "./holiday-leave-requests.service";
// import { SickLeaveRequestsService } from "./sick-leave-requests.service";
// import { VacationLeaveRequestsService } from "./vacation-leave-requests.service";
// import { HolidayService } from "src/modules/business-logics/services/holiday.service";
// import { SickLeaveService } from "src/modules/business-logics/services/sick-leave.service";
// import { VacationService } from "src/modules/business-logics/services/vacation.service";
// import { PrismaService } from "src/prisma/prisma.service";
// import { LeaveRequestsUtils } from "../utils/leave-request.util";
// import { normalizeDates, toDateOnly, toISODateKey } from "src/modules/shared/helpers/date-time.helpers";
// import { EmailToIdResolver } from "src/modules/shared/utils/resolve-email-id.utils";
// import { BankCodesResolver } from "src/modules/shared/utils/resolve-bank-type-id.utils";

// @Injectable()
// export class LeaveRequestsService {
//     constructor(
//         private readonly prisma:               PrismaService,
//         private readonly holidayLeaveService:  HolidayLeaveRequestsService,
//         private readonly holidayService:       HolidayService,
//         private readonly sickLogic:            SickLeaveService,
//         private readonly sickLeaveService:     SickLeaveRequestsService,
//         private readonly vacationLeaveService: VacationLeaveRequestsService,
//         private readonly vacationLogic:        VacationService,
//         private readonly leaveUtils:           LeaveRequestsUtils,
//         private readonly emailResolver:        EmailToIdResolver,
//         private readonly typeResolver:         BankCodesResolver,
//     ) {}

//     //handle distribution to the right service according to the selected type and action
//     async handle(dto: UpsertLeaveRequestDto): Promise<UpsertResult> {
//         switch (dto.type) {
//             case LeaveTypes.HOLIDAY:
//                 if( dto.action === 'create'){
//                     return this.holidayLeaveService.create(dto);
//                 } else if (dto.action === 'update') {
//                     return this.update(dto, LeaveTypes.HOLIDAY);
//                 } else if (dto.action === 'delete'){
//                     return this.delete(dto, LeaveTypes.HOLIDAY);
//                 }
//             case LeaveTypes.VACATION:
//                 if( dto.action === 'create'){
//                     return this.vacationLeaveService.create(dto);
//                 } else if (dto.action === 'update') {
//                     return this.update(dto, LeaveTypes.VACATION);
//                 } else if (dto.action === 'delete'){
//                     return this.delete(dto, LeaveTypes.VACATION);
//                 }
//             case LeaveTypes.SICK:
//                 if( dto.action === 'create'){
//                     return this.sickLeaveService.create(dto);
//                 } else if (dto.action === 'update') {
//                     return this.update(dto, LeaveTypes.SICK);
//                 } else if (dto.action === 'delete'){
//                     return this.delete(dto, LeaveTypes.SICK);
//                 }
//             default:
//                 throw new BadRequestException(`Unsupported leave type: ${dto.type} or action: ${dto.action}`);
//         }
//     }

//     async delete(dto: UpsertLeaveRequestDto, type: LeaveTypes): Promise<UpsertResult> {
//         const email       = dto.email.trim();
//         const dates       = normalizeDates(dto.dates);
//         const employee_id = await this.emailResolver.findIdByEmail(email);
//         if (!dates.length) throw new BadRequestException("Dates array must not be empty");

//         const rows = await this.prisma.leaveRequests.findMany({
//             where: {
//                 employee_id: employee_id,
//                 leave_type: type,
//                 date: { in: dates.map((d) => toDateOnly(d)) },
//             },
//             select: leaveRequestsSelect,
//         });

//         if (rows.length !== dates.length) {
//             const missing = dates.filter((isoDate) => !rows.some((row) => toISODateKey(row.date) === isoDate));
//             throw new NotFoundException(`No Leave request found for: ${missing.join(", ")}`);
//         }

//         for (const row of rows) {
//             if (row.approval_status === LeaveApprovalStatus.APPROVED) {
//                 const iso = toISODateKey(row.date);
//                 await this.leaveUtils.removeShift(email, employee_id, iso, type);
//             }
//         }

//         await this.prisma.leaveRequests.deleteMany({
//             where: { id: { in: rows.map((row) => row.id) } },
//         });

//         const deleted = rows.map((row) => ({ ...mapRowToView(row), action: "delete" as const }));
//         return { action: "delete", leave_requests: deleted };
//     }

//     async update(dto: UpsertLeaveRequestDto, type: LeaveTypes): Promise<UpsertResult> {
//         const email       = dto.email.trim();
//         const employee_id = await this.emailResolver.findIdByEmail(email);
//         const bank_code   = await this.typeResolver.findByType(type);
//         if(!bank_code) throw new NotFoundException(`bank_code not found`);
//         const modifier    = Number(bank_code.modifier ?? 1);
//         const dates       = normalizeDates(dto.dates);
//         if (!dates.length) {
//             throw new BadRequestException("Dates array must not be empty");
//         }

//         const entries = await Promise.all(
//             dates.map(async (iso_date) => {
//                 const date     = toDateOnly(iso_date);
//                 const existing = await this.prisma.leaveRequests.findUnique({
//                     where: {
//                         leave_per_employee_date: {
//                             employee_id: employee_id,
//                             leave_type:  type,
//                             date,
//                         },
//                     },
//                     select: leaveRequestsSelect,
//                 });
//                 if (!existing) throw new NotFoundException(`No Leave request found for ${iso_date}`);
//                 return { iso_date, date, existing };
//             }),
//         );

//         const updated: LeaveRequestViewDto[] = [];

//         if (type === LeaveTypes.SICK) {
//             const firstExisting = entries[0].existing;
//             const fallbackRequested =
//                 firstExisting.requested_hours !== null && firstExisting.requested_hours !== undefined
//                     ? Number(firstExisting.requested_hours)
//                     : 8;
//             const requested_hours_per_day = dto.requested_hours ?? fallbackRequested;
//             const reference_date          = entries.reduce(
//                 (latest, entry) => (entry.date > latest ? entry.date : latest),
//                 entries[0].date,
//             );
//             const total_payable_hours = await this.sickLogic.calculateSickLeavePay(
//                 employee_id,
//                 reference_date,
//                 entries.length,
//                 requested_hours_per_day,
//                 modifier,
//             );
//             let remaining_payable_hours = roundToQuarterHour(Math.max(0, total_payable_hours));
//             const daily_payable_cap = roundToQuarterHour(requested_hours_per_day * modifier);

//             for (const { iso_date, existing } of entries) {
//                 const previous_status   = existing.approval_status;
//                 const payable           = Math.min(remaining_payable_hours, daily_payable_cap);
//                 const payable_rounded   = roundToQuarterHour(Math.max(0, payable));
//                 remaining_payable_hours = roundToQuarterHour(
//                     Math.max(0, remaining_payable_hours - payable_rounded),
//                 );

//                 const row = await this.prisma.leaveRequests.update({
//                     where: { id: existing.id },
//                     data: {
//                         comment:         dto.comment ?? existing.comment,
//                         requested_hours: requested_hours_per_day,
//                         payable_hours:   payable_rounded,
//                         bank_code_id:    bank_code.id,
//                         approval_status: dto.approval_status ?? existing.approval_status,
//                     },
//                     select: leaveRequestsSelect,
//                 });

//                 const was_approved = previous_status === LeaveApprovalStatus.APPROVED;
//                 const is_approved  = row.approval_status === LeaveApprovalStatus.APPROVED;
//                 const hours        = Number(row.payable_hours ?? row.requested_hours ?? 0);

//                 if (!was_approved && is_approved) {
//                     await this.leaveUtils.syncShift(email, employee_id, iso_date, hours, type, row.comment);
//                 } else if (was_approved && !is_approved) {
//                     await this.leaveUtils.removeShift(email, employee_id, iso_date, type);
//                 } else if (was_approved && is_approved) {
//                     await this.leaveUtils.syncShift(email, employee_id, iso_date, hours, type, row.comment);
//                 }
//                 updated.push({ ...mapRowToView(row), action: "update" });
//             }
//             return { action: "update", leave_requests: updated };
//         }

//         for (const { iso_date, date, existing } of entries) {
//             const previous_status = existing.approval_status;
//             const fallbackRequested =
//                 existing.requested_hours !== null && existing.requested_hours !== undefined
//                     ? Number(existing.requested_hours)
//                     : 8;
//             const requested_hours = dto.requested_hours ?? fallbackRequested;

//             let payable: number;
//             switch (type) {
//                 case LeaveTypes.HOLIDAY:
//                     payable = await this.holidayService.calculateHolidayPay(email, date, modifier);
//                     break;
//                 case LeaveTypes.VACATION: {
//                     const days_requested = requested_hours / 8;
//                     payable = await this.vacationLogic.calculateVacationPay(
//                         employee_id,
//                         date,
//                         Math.max(0, days_requested),
//                         modifier,
//                     );
//                     break;
//                 }
//                 default:
//                     payable = existing.payable_hours !== null && existing.payable_hours !== undefined
//                             ? Number(existing.payable_hours)
//                             : requested_hours;
//             }

//             const row = await this.prisma.leaveRequests.update({
//                 where: { id: existing.id },
//                 data: {
//                     requested_hours,
//                     comment:         dto.comment ?? existing.comment,
//                     payable_hours:   payable,
//                     bank_code_id:    bank_code.id,
//                     approval_status: dto.approval_status ?? existing.approval_status,
//                 },
//                 select: leaveRequestsSelect,
//             });

//             const was_approved = previous_status === LeaveApprovalStatus.APPROVED;
//             const is_approved  = row.approval_status === LeaveApprovalStatus.APPROVED;
//             const hours        = Number(row.payable_hours ?? row.requested_hours ?? 0);

//             if (!was_approved && is_approved) {
//                 await this.leaveUtils.syncShift(email, employee_id, iso_date, hours, type, row.comment);
//             } else if (was_approved && !is_approved) {
//                 await this.leaveUtils.removeShift(email, employee_id, iso_date, type);
//             } else if (was_approved && is_approved) {
//                 await this.leaveUtils.syncShift(email, employee_id, iso_date, hours, type, row.comment);
//             }
//             updated.push({ ...mapRowToView(row), action: "update" });
//         }
//         return { action: "update", leave_requests: updated };
//     }
// }