using Marco.Pms.DataAccess.Data;
using Marco.Pms.Model.Directory;
using Marco.Pms.Model.Dtos.Master;
using Marco.Pms.Model.Employees;
using Marco.Pms.Model.Entitlements;
using Marco.Pms.Model.Mapper;
using Marco.Pms.Model.Master;
using Marco.Pms.Model.Utilities;
using Marco.Pms.Model.ViewModels.Master;
using Marco.Pms.Services.Service;
using MarcoBMS.Services.Helpers;
using MarcoBMS.Services.Service;
using Microsoft.EntityFrameworkCore;

namespace Marco.Pms.Services.Helpers
{
    public class MasterHelper
    {
        private readonly ApplicationDbContext _context;
        private readonly ILoggingService _logger;
        private readonly UserHelper _userHelper;
        private readonly PermissionServices _permissionService;


        public MasterHelper(ApplicationDbContext context, ILoggingService logger, UserHelper userHelper, PermissionServices permissionServices)
        {
            _context = context;
            _logger = logger;
            _userHelper = userHelper;
            _permissionService = permissionServices;
        }
        // -------------------------------- Contact Category  --------------------------------
        public async Task<ApiResponse<object>> CreateContactCategory(CreateContactCategoryDto contactCategoryDto)
        {
            Guid tenantId = _userHelper.GetTenantId();
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            if (contactCategoryDto != null)
            {
                ContactCategoryMaster? existingContactCategory = await _context.ContactCategoryMasters.FirstOrDefaultAsync(c => c.TenantId == tenantId && c.Name.ToLower() == (contactCategoryDto.Name != null ? contactCategoryDto.Name.ToLower() : ""));
                if (existingContactCategory == null)
                {
                    ContactCategoryMaster contactCategory = contactCategoryDto.ToContactCategoryMasterFromCreateContactCategoryDto(tenantId);
                    _context.ContactCategoryMasters.Add(contactCategory);
                    await _context.SaveChangesAsync();
                    ContactCategoryVM categoryVM = contactCategory.ToContactCategoryVMFromContactCategoryMaster();

                    _logger.LogInfo("Employee ID {LoggedInEmployeeId} created a contact category {ContactCategoryId}.", LoggedInEmployee.Id, contactCategory.Id);
                    return ApiResponse<object>.SuccessResponse(categoryVM, "Category Created Successfully", 200);
                }
                _logger.LogWarning("Employee ID {LoggedInEmployeeId} attempted to create an existing contact category.", LoggedInEmployee.Id);
                return ApiResponse<object>.ErrorResponse("Category already existed", "Category already existed", 409);
            }
            _logger.LogWarning("Employee with ID {LoggedInEmployeeId} sended empty payload", LoggedInEmployee.Id);
            return ApiResponse<object>.ErrorResponse("User Send empty Payload", "User Send empty Payload", 400);
        }
        public async Task<ApiResponse<object>> UpdateContactCategory(Guid id, UpdateContactCategoryDto contactCategoryDto)
        {
            Guid tenantId = _userHelper.GetTenantId();
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            if (contactCategoryDto != null && id == contactCategoryDto.Id)
            {
                ContactCategoryMaster? contactCategory = await _context.ContactCategoryMasters.FirstOrDefaultAsync(c => c.TenantId == tenantId && c.Id == id);
                if (contactCategory != null)
                {
                    contactCategory.Name = contactCategoryDto.Name ?? "";
                    contactCategory.Description = contactCategoryDto.Description ?? "";

                    _context.DirectoryUpdateLogs.Add(new DirectoryUpdateLog
                    {
                        RefereanceId = contactCategory.Id,
                        UpdatedById = LoggedInEmployee.Id,
                        UpdateAt = DateTime.UtcNow
                    });

                    await _context.SaveChangesAsync();
                    ContactCategoryVM categoryVM = contactCategory.ToContactCategoryVMFromContactCategoryMaster();

                    _logger.LogInfo("Employee ID {LoggedInEmployeeId} created a contact category {ContactCategoryId}.", LoggedInEmployee.Id, contactCategory.Id);
                    return ApiResponse<object>.SuccessResponse(categoryVM, "Category Created Successfully", 200);
                }
                _logger.LogWarning("Employee ID {LoggedInEmployeeId} attempted to update a contact category but not found in database.", LoggedInEmployee.Id);
                return ApiResponse<object>.ErrorResponse("Category not found", "Category not found", 404);
            }
            _logger.LogWarning("Employee with ID {LoggedInEmployeeId} sended empty payload", LoggedInEmployee.Id);
            return ApiResponse<object>.ErrorResponse("User Send empty Payload", "User Send empty Payload", 400);
        }
        public async Task<ApiResponse<object>> GetContactCategoriesList()
        {
            Guid tenantId = _userHelper.GetTenantId();
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

            var categoryList = await _context.ContactCategoryMasters.Where(c => c.TenantId == tenantId).ToListAsync();
            List<ContactCategoryVM> contactCategories = new List<ContactCategoryVM>();
            foreach (var category in categoryList)
            {
                ContactCategoryVM categoryVM = category.ToContactCategoryVMFromContactCategoryMaster();
                contactCategories.Add(categoryVM);
            }
            _logger.LogInfo("{count} contact categoires are fetched by Employee with ID {LoggedInEmployeeId}", contactCategories.Count, LoggedInEmployee.Id);
            return ApiResponse<object>.SuccessResponse(contactCategories, System.String.Format("{0} contact categories fetched successfully", contactCategories.Count), 200);
        }
        public async Task<ApiResponse<object>> GetContactCategoryById(Guid id)
        {
            Guid tenantId = _userHelper.GetTenantId();
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

            var category = await _context.ContactCategoryMasters.FirstOrDefaultAsync(c => c.Id == id && c.TenantId == tenantId);
            if (category != null)
            {
                ContactCategoryVM categoryVM = category.ToContactCategoryVMFromContactCategoryMaster();
                _logger.LogInfo("Employee {EmployeeId} fetched contact category {ContactCategoryID}", LoggedInEmployee.Id, category.Id);
                return ApiResponse<object>.SuccessResponse(categoryVM, "Category fetched successfully", 200);
            }

            _logger.LogWarning("Employee {EmployeeId} attempted to fetch contact category {ContactCategoryID} but not found in database", LoggedInEmployee.Id, id);
            return ApiResponse<object>.ErrorResponse("Category not found", "Category not found", 404);
        }
        public async Task<ApiResponse<object>> DeleteContactCategory(Guid id)
        {
            Guid tenantId = _userHelper.GetTenantId();
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            ContactCategoryMaster? contactCategory = await _context.ContactCategoryMasters.FirstOrDefaultAsync(c => c.Id == id && c.TenantId == tenantId);
            if (contactCategory != null)
            {
                List<Contact>? existingContacts = await _context.Contacts.AsNoTracking().Where(c => c.ContactCategoryId == contactCategory.Id).ToListAsync();
                if (existingContacts.Count > 0)
                {
                    List<Contact>? contacts = new List<Contact>();
                    foreach (var contact in existingContacts)
                    {
                        contact.ContactCategoryId = null;
                        contacts.Add(contact);
                    }
                    _context.Contacts.UpdateRange(contacts);
                }
                _context.ContactCategoryMasters.Remove(contactCategory);

                _context.DirectoryUpdateLogs.Add(new DirectoryUpdateLog
                {
                    RefereanceId = id,
                    UpdatedById = LoggedInEmployee.Id,
                    UpdateAt = DateTime.UtcNow
                });
                await _context.SaveChangesAsync();
                _logger.LogInfo("Employee {EmployeeId} deleted contact category {ContactCategoryId}", LoggedInEmployee.Id, id);
            }

            _logger.LogWarning("Employee {EmployeeId} tries to delete Category {CategoryId} but not found in database", LoggedInEmployee.Id, id);
            return ApiResponse<object>.SuccessResponse(new { }, "Category deleted successfully", 200);
        }

        // -------------------------------- Contact Tag  --------------------------------


        public async Task<ApiResponse<Object>> GetContactTags()
        {
            Guid tenantId = _userHelper.GetTenantId();

            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

            var taglist = await _context.ContactTagMasters.Where(t => t.TenantId == tenantId).ToListAsync();
            List<ContactTagVM> contactTags = new List<ContactTagVM>();
            foreach (var tag in taglist)
            {
                ContactTagVM tagVm = tag.ToContactTagVMFromContactTagMaster();
                contactTags.Add(tagVm);
            }
            _logger.LogInfo("{count} contact Tags are fetched by Employee with ID {LoggedInEmployeeId}", contactTags.Count, LoggedInEmployee.Id);
            return ApiResponse<object>.SuccessResponse(contactTags, System.String.Format("{0} contact tags fetched successfully", contactTags.Count), 200);
        }
        public async Task<ApiResponse<object>> CreateContactTag(CreateContactTagDto contactTagDto)
        {
            Guid tenantId = _userHelper.GetTenantId();
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            if (contactTagDto != null)
            {
                ContactTagMaster? existingContactTag = await _context.ContactTagMasters.FirstOrDefaultAsync(c => c.TenantId == tenantId && c.Name.ToLower() == (contactTagDto.Name != null ? contactTagDto.Name.ToLower() : ""));
                if (existingContactTag == null)
                {
                    ContactTagMaster contactTag = contactTagDto.ToContactTagMasterFromCreateContactTagDto(tenantId);
                    _context.ContactTagMasters.Add(contactTag);
                    await _context.SaveChangesAsync();
                    ContactTagVM tagVM = contactTag.ToContactTagVMFromContactTagMaster();

                    _logger.LogInfo("Employee ID {LoggedInEmployeeId} created a contact tag {ContactTagId}.", LoggedInEmployee.Id, contactTag.Id);
                    return ApiResponse<object>.SuccessResponse(tagVM, "Tag Created Successfully", 200);
                }
                _logger.LogWarning("Employee ID {LoggedInEmployeeId} attempted to create an existing contact tag.", LoggedInEmployee.Id);
                return ApiResponse<object>.ErrorResponse("Tag already existed", "Tag already existed", 409);
            }
            _logger.LogWarning("Employee with ID {LoggedInEmployeeId} sended empty payload", LoggedInEmployee.Id);
            return ApiResponse<object>.ErrorResponse("User Send empty Payload", "User Send empty Payload", 400);
        }
        public async Task<ApiResponse<object>> UpdateContactTag(Guid id, UpdateContactTagDto contactTagDto)
        {
            var tenantId = _userHelper.GetTenantId();
            Employee LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            if (contactTagDto != null && contactTagDto.Id == id)
            {
                ContactTagMaster? contactTag = await _context.ContactTagMasters.AsNoTracking().FirstOrDefaultAsync(t => t.TenantId == tenantId && t.Id == contactTagDto.Id);
                if (contactTag != null)
                {
                    contactTag = contactTagDto.ToContactTagMasterFromUpdateContactTagDto(tenantId);
                    _context.ContactTagMasters.Update(contactTag);

                    _context.DirectoryUpdateLogs.Add(new DirectoryUpdateLog
                    {
                        RefereanceId = contactTag.Id,
                        UpdatedById = LoggedInEmployee.Id,
                        UpdateAt = DateTime.UtcNow
                    });
                    await _context.SaveChangesAsync();

                    ContactTagVM contactTagVm = contactTag.ToContactTagVMFromContactTagMaster();



                    _logger.LogInfo("Contact tag master {ConatctTagId} updated successfully by employee {EmployeeId}", contactTagVm.Id, LoggedInEmployee.Id);
                    return ApiResponse<object>.SuccessResponse(contactTagVm, "Contact Tag master updated successfully", 200);
                }
                _logger.LogWarning("Contact Tag master {ContactTagId} not found in database", id);
                return ApiResponse<object>.ErrorResponse("Contact Tag master not found", "Contact tag master not found", 404);
            }
            _logger.LogWarning("Employee with ID {LoggedInEmployeeId} sended empty payload", LoggedInEmployee.Id);
            return ApiResponse<object>.ErrorResponse("User Send empty Payload", "User Send empty Payload", 400);
        }
        public async Task<ApiResponse<object>> DeleteContactTag(Guid id)
        {
            Guid tenantId = _userHelper.GetTenantId();
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            ContactTagMaster? contactTag = await _context.ContactTagMasters.FirstOrDefaultAsync(c => c.Id == id && c.TenantId == tenantId);
            if (contactTag != null)
            {
                List<ContactTagMapping>? tagMappings = await _context.ContactTagMappings.Where(t => t.ContactTagId == contactTag.Id).ToListAsync();

                _context.ContactTagMasters.Remove(contactTag);
                if (tagMappings.Any())
                {
                    _context.ContactTagMappings.RemoveRange(tagMappings);
                }
                _context.DirectoryUpdateLogs.Add(new DirectoryUpdateLog
                {
                    RefereanceId = id,
                    UpdatedById = LoggedInEmployee.Id,
                    UpdateAt = DateTime.UtcNow
                });
                await _context.SaveChangesAsync();
                _logger.LogInfo("Employee {EmployeeId} deleted contact tag {ContactTagId}", LoggedInEmployee.Id, id);
            }

            _logger.LogWarning("Employee {EmployeeId} tries to delete Tag {ContactTagId} but not found in database", LoggedInEmployee.Id, id);
            return ApiResponse<object>.SuccessResponse(new { }, "Tag deleted successfully", 200);
        }

        // -------------------------------- Work Status  --------------------------------
        public async Task<ApiResponse<object>> GetWorkStatusList()
        {
            _logger.LogInfo("GetWorkStatusList called.");

            try
            {
                // Step 1: Get tenant and logged-in employee info
                Guid tenantId = _userHelper.GetTenantId();
                var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

                // Step 2: Check permission to view master data
                bool hasViewPermission = await _permissionService.HasPermission(PermissionsMaster.ViewMasters, loggedInEmployee.Id);
                if (!hasViewPermission)
                {
                    _logger.LogWarning("Access denied for employeeId: {EmployeeId}", loggedInEmployee.Id);
                    return ApiResponse<object>.ErrorResponse("You don't have access", "Don't have access to take action", 403);
                }

                // Step 3: Fetch work statuses for the tenant
                var workStatusList = await _context.WorkStatusMasters
                    .Where(ws => ws.TenantId == tenantId)
                    .Select(ws => new
                    {
                        ws.Id,
                        ws.Name,
                        ws.Description,
                        ws.IsSystem
                    })
                    .ToListAsync();

                _logger.LogInfo("{Count} work statuses fetched for tenantId: {TenantId}", workStatusList.Count, tenantId);

                // Step 4: Return successful response
                return ApiResponse<object>.SuccessResponse(
                    workStatusList,
                    $"{workStatusList.Count} work status records fetched successfully",
                    200
                );
            }
            catch (Exception ex)
            {
                _logger.LogWarning("Error occurred while fetching work status list : {Error}", ex.Message);
                return ApiResponse<object>.ErrorResponse("An error occurred", "Unable to fetch work status list", 500);
            }
        }
        public async Task<ApiResponse<object>> CreateWorkStatus(CreateWorkStatusMasterDto createWorkStatusDto)
        {
            _logger.LogInfo("CreateWorkStatus called with Name: {Name}", createWorkStatusDto.Name ?? "");

            try
            {
                // Step 1: Get tenant and logged-in employee
                Guid tenantId = _userHelper.GetTenantId();
                var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

                // Step 2: Check if user has permission to manage master data
                var hasManageMasterPermission = await _permissionService.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
                if (!hasManageMasterPermission)
                {
                    _logger.LogWarning("Access denied for employeeId: {EmployeeId}", loggedInEmployee.Id);
                    return ApiResponse<object>.ErrorResponse("You don't have access", "Don't have access to take action", 403);
                }

                // Step 3: Check if work status with the same name already exists
                var existingWorkStatus = await _context.WorkStatusMasters
                    .FirstOrDefaultAsync(ws => ws.Name == createWorkStatusDto.Name && ws.TenantId == tenantId);

                if (existingWorkStatus != null)
                {
                    _logger.LogWarning("Work status already exists: {Name}", createWorkStatusDto.Name ?? "");
                    return ApiResponse<object>.ErrorResponse("Work status already exists", "Work status already exists", 400);
                }

                // Step 4: Create new WorkStatusMaster entry
                var workStatus = new WorkStatusMaster
                {
                    Name = createWorkStatusDto.Name?.Trim() ?? "",
                    Description = createWorkStatusDto.Description?.Trim() ?? "",
                    IsSystem = false,
                    TenantId = tenantId
                };

                _context.WorkStatusMasters.Add(workStatus);
                await _context.SaveChangesAsync();

                _logger.LogInfo("Work status created successfully: {Id}, Name: {Name}", workStatus.Id, workStatus.Name);
                return ApiResponse<object>.SuccessResponse(workStatus, "Work status created successfully", 200);
            }
            catch (Exception ex)
            {
                _logger.LogWarning("Error occurred while creating work status : {Error}", ex.Message);
                return ApiResponse<object>.ErrorResponse("An error occurred", "Unable to create work status", 500);
            }
        }
        public async Task<ApiResponse<object>> UpdateWorkStatus(Guid id, UpdateWorkStatusMasterDto updateWorkStatusDto)
        {
            _logger.LogInfo("UpdateWorkStatus called for WorkStatus ID: {Id}, New Name: {Name}", id, updateWorkStatusDto.Name ?? "");

            try
            {
                // Step 1: Validate input
                if (id == Guid.Empty || id != updateWorkStatusDto.Id)
                {
                    _logger.LogWarning("Invalid ID provided for update. Route ID: {RouteId}, DTO ID: {DtoId}", id, updateWorkStatusDto.Id);
                    return ApiResponse<object>.ErrorResponse("Invalid data provided", "The provided work status ID is invalid", 400);
                }

                // Step 2: Get tenant and logged-in employee
                Guid tenantId = _userHelper.GetTenantId();
                var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

                // Step 3: Check permissions
                var hasManageMasterPermission = await _permissionService.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
                if (!hasManageMasterPermission)
                {
                    _logger.LogWarning("Access denied. EmployeeId: {EmployeeId} does not have Manage Master permission.", loggedInEmployee.Id);
                    return ApiResponse<object>.ErrorResponse("Access denied", "You do not have permission to update this work status", 403);
                }

                // Step 4: Retrieve the work status record
                var workStatus = await _context.WorkStatusMasters
                    .FirstOrDefaultAsync(ws => ws.Id == id && ws.TenantId == tenantId);

                if (workStatus == null)
                {
                    _logger.LogWarning("Work status not found for ID: {Id}", id);
                    return ApiResponse<object>.ErrorResponse("Work status not found", "No work status found with the provided ID", 404);
                }

                // Step 5: Check for duplicate name (optional)
                var isDuplicate = await _context.WorkStatusMasters
                    .AnyAsync(ws => ws.Name == updateWorkStatusDto.Name && ws.Id != id && ws.TenantId == tenantId);

                if (isDuplicate)
                {
                    _logger.LogWarning("Duplicate work status name '{Name}' detected during update. ID: {Id}", updateWorkStatusDto.Name ?? "", id);
                    return ApiResponse<object>.ErrorResponse("Work status with the same name already exists", "Duplicate name", 400);
                }

                // Step 6: Update fields
                workStatus.Name = updateWorkStatusDto.Name?.Trim() ?? "";
                workStatus.Description = updateWorkStatusDto.Description?.Trim() ?? "";

                await _context.SaveChangesAsync();

                _logger.LogInfo("Work status updated successfully. ID: {Id}", id);
                return ApiResponse<object>.SuccessResponse(workStatus, "Work status updated successfully", 200);
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error occurred while updating work status ID: {Id}", id);
                return ApiResponse<object>.ErrorResponse("An error occurred", "Unable to update the work status at this time", 500);
            }
        }
        public async Task<ApiResponse<object>> DeleteWorkStatus(Guid id)
        {
            _logger.LogInfo("DeleteWorkStatus called for Id: {Id}", id);

            try
            {
                // Step 1: Get current tenant and logged-in employee
                Guid tenantId = _userHelper.GetTenantId();
                var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

                // Step 2: Check permission to manage master data
                var hasManageMasterPermission = await _permissionService.HasPermission(PermissionsMaster.ManageMasters, loggedInEmployee.Id);
                if (!hasManageMasterPermission)
                {
                    _logger.LogWarning("Delete denied. EmployeeId: {EmployeeId} lacks Manage_Master permission.", loggedInEmployee.Id);
                    return ApiResponse<object>.ErrorResponse("You don't have access", "Access denied for deleting work status", 403);
                }

                // Step 3: Find the work status
                var workStatus = await _context.WorkStatusMasters
                    .FirstOrDefaultAsync(ws => ws.Id == id && ws.TenantId == tenantId);

                if (workStatus == null)
                {
                    _logger.LogWarning("Work status not found for Id: {Id}", id);
                    return ApiResponse<object>.ErrorResponse("Work status not found", "Work status not found", 404);
                }

                // Step 4: Check for dependencies in TaskAllocations
                bool hasDependency = await _context.TaskAllocations
                    .AnyAsync(ta => ta.TenantId == tenantId && ta.WorkStatusId == id);

                if (hasDependency)
                {
                    _logger.LogWarning("Cannot delete WorkStatus Id: {Id} due to existing task dependency", id);
                    return ApiResponse<object>.ErrorResponse(
                        "Work status has a dependency in assigned tasks and cannot be deleted",
                        "Deletion failed due to associated tasks",
                        400
                    );
                }

                // Step 5: Delete and persist
                _context.WorkStatusMasters.Remove(workStatus);
                await _context.SaveChangesAsync();

                _logger.LogInfo("Work status deleted successfully. Id: {Id}", id);
                return ApiResponse<object>.SuccessResponse(new { }, "Work status deleted successfully", 200);
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error occurred while deleting WorkStatus Id: {Id}", id);
                return ApiResponse<object>.ErrorResponse("An error occurred", "Unable to delete work status", 500);
            }
        }
    }
}