using Marco.Pms.DataAccess.Data;
using Marco.Pms.Model.Dtos.Project;
using Marco.Pms.Model.Employees;
using Marco.Pms.Model.Mapper;
using Marco.Pms.Model.Projects;
using Marco.Pms.Model.Utilities;
using Marco.Pms.Model.ViewModels.Projects;
using Marco.Pms.Services.Helpers;
using Marco.Pms.Services.Service;
using Marco.Pms.Services.Service.ServiceInterfaces;
using MarcoBMS.Services.Helpers;
using MarcoBMS.Services.Service;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.CodeAnalysis;
using Microsoft.EntityFrameworkCore;
using MongoDB.Driver;

namespace MarcoBMS.Services.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    [Authorize]
    public class ProjectController : ControllerBase
    {
        private readonly IProjectServices _projectServices;
        private readonly ApplicationDbContext _context;
        private readonly UserHelper _userHelper;
        private readonly ILoggingService _logger;
        private readonly ISignalRService _signalR;
        private readonly PermissionServices _permission;
        private readonly CacheUpdateHelper _cache;
        private readonly Guid tenantId;


        public ProjectController(
            ApplicationDbContext context,
            UserHelper userHelper,
            ILoggingService logger,
            ISignalRService signalR,
            CacheUpdateHelper cache,
            PermissionServices permission,
            IProjectServices projectServices)
        {
            _context = context;
            _userHelper = userHelper;
            _logger = logger;
            _signalR = signalR;
            _cache = cache;
            _permission = permission;
            _projectServices = projectServices;
            tenantId = userHelper.GetTenantId();
        }

        #region =================================================================== Project Get APIs ===================================================================

        [HttpGet("list/basic")]
        public async Task<IActionResult> GetAllProjectsBasic()
        {
            // Get the current user
            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetAllProjectsBasicAsync(tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }

        /// <summary>
        /// Retrieves a list of projects accessible to the current user, including aggregated details.
        /// This method is optimized to use a cache-first approach. If data is not in the cache,
        /// it fetches and aggregates data efficiently from the database in parallel.
        /// </summary>
        /// <returns>An ApiResponse containing a list of projects or an error.</returns>

        [HttpGet("list")]
        public async Task<IActionResult> GetAllProjects()
        {
            // --- Input Validation and Initial Setup ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values
                    .SelectMany(v => v.Errors)
                    .Select(e => e.ErrorMessage)
                    .ToList();
                _logger.LogWarning("GetAllProjects called with invalid model state. Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }
            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetAllProjectsAsync(tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }

        /// <summary>
        /// Retrieves details for a specific project by its ID.
        /// This endpoint is optimized with a cache-first strategy and parallel permission checks.
        /// </summary>
        /// <param name="id">The unique identifier of the project.</param>
        /// <returns>An ApiResponse containing the project details or an appropriate error.</returns>

        [HttpGet("get/{id}")]
        public async Task<IActionResult> GetProject([FromRoute] Guid id)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("Get project called with invalid model state for ID {ProjectId}. Errors: {Errors}", id, string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetProjectAsync(id, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }


        [HttpGet("details/{id}")]
        public async Task<IActionResult> GetProjectDetails([FromRoute] Guid id)
        {
            // Step 1: Validate model state
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values
                    .SelectMany(v => v.Errors)
                    .Select(e => e.ErrorMessage)
                    .ToList();

                _logger.LogWarning("Invalid model state in Details endpoint. Errors: {@Errors}", errors);
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid data", errors, 400));
            }

            // Step 2: Get logged-in employee
            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

            var response = await _projectServices.GetProjectDetailsAsync(id, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }

        [HttpGet("details-old/{id}")]
        public async Task<IActionResult> GetProjectDetailsOld([FromRoute] Guid id)
        {
            // ProjectDetailsVM vm = new ProjectDetailsVM();

            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values
                    .SelectMany(v => v.Errors)
                    .Select(e => e.ErrorMessage)
                    .ToList();
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid data", errors, 400));

            }

            var loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

            var response = await _projectServices.GetProjectDetailsAsync(id, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);

        }

        #endregion

        #region =================================================================== Project Manage APIs ===================================================================

        [HttpPost]
        public async Task<IActionResult> CreateProject([FromBody] CreateProjectDto projectDto)
        {
            // 1. Validate input first (early exit)
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid data", errors, 400));
            }

            // 2. Prepare data without I/O
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.CreateProjectAsync(projectDto, tenantId, loggedInEmployee);
            if (response.Success)
            {
                var notification = new { LoggedInUserId = loggedInEmployee.Id, Keyword = "Create_Project", Response = response.Data };
                await _signalR.SendNotificationAsync(notification);
            }
            return StatusCode(response.StatusCode, response);
        }

        /// <summary>
        /// Updates an existing project's details.
        /// This endpoint is secure, handles concurrency, and performs non-essential tasks in the background.
        /// </summary>
        /// <param name="id">The ID of the project to update.</param>
        /// <param name="updateProjectDto">The data to update the project with.</param>
        /// <returns>An ApiResponse confirming the update or an appropriate error.</returns>

        [HttpPut("update/{id}")]
        public async Task<IActionResult> UpdateProject([FromRoute] Guid id, [FromBody] UpdateProjectDto updateProjectDto)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("Update project called with invalid model state for ID {ProjectId}. Errors: {Errors}", id, string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.UpdateProjectAsync(id, updateProjectDto, tenantId, loggedInEmployee);
            if (response.Success)
            {
                var notification = new { LoggedInUserId = loggedInEmployee.Id, Keyword = "Update_Project", Response = response.Data };
                await _signalR.SendNotificationAsync(notification);
            }
            return StatusCode(response.StatusCode, response);
        }

        #endregion

        #region =================================================================== Project Allocation APIs ===================================================================

        [HttpGet("employees/get/{projectid?}/{includeInactive?}")]
        public async Task<IActionResult> GetEmployeeByProjectId(Guid? projectId, bool includeInactive = false)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("Get employee list by ProjectId called with invalid model state \n Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetEmployeeByProjectIdAsync(projectId, includeInactive, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }

        [HttpGet("allocation/{projectId}")]
        public async Task<IActionResult> GetProjectAllocation(Guid? projectId)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("Get employee list by ProjectId called with invalid model state \n Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetProjectAllocationAsync(projectId, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }

        [HttpPost("allocation")]
        public async Task<IActionResult> ManageAllocation([FromBody] List<ProjectAllocationDot> projectAllocationDot)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("project Alocation called with invalid model state for list of projects. Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.ManageAllocationAsync(projectAllocationDot, tenantId, loggedInEmployee);
            if (response.Success)
            {
                List<Guid> employeeIds = response.Data.Select(pa => pa.EmployeeId).ToList();
                List<Guid> projectIds = response.Data.Select(pa => pa.ProjectId).ToList();

                var notification = new { LoggedInUserId = loggedInEmployee.Id, Keyword = "Assign_Project", ProjectIds = projectIds, EmployeeList = employeeIds };
                await _signalR.SendNotificationAsync(notification);
            }
            return StatusCode(response.StatusCode, response);

        }

        [HttpGet("assigned-projects/{employeeId}")]
        public async Task<IActionResult> GetProjectsByEmployee([FromRoute] Guid employeeId)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("Get project list by employee Id called with invalid model state \n Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetProjectsByEmployeeAsync(employeeId, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }

        [HttpPost("assign-projects/{employeeId}")]
        public async Task<IActionResult> AssigneProjectsToEmployee([FromBody] List<ProjectsAllocationDto> projectAllocationDtos, [FromRoute] Guid employeeId)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("project Alocation called with invalid model state for list of projects. Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.AssigneProjectsToEmployeeAsync(projectAllocationDtos, employeeId, tenantId, loggedInEmployee);
            if (response.Success)
            {
                List<Guid> projectIds = response.Data.Select(pa => pa.ProjectId).ToList();

                var notification = new { LoggedInUserId = loggedInEmployee.Id, Keyword = "Assign_Project", ProjectIds = projectIds, EmployeeId = employeeId };
                await _signalR.SendNotificationAsync(notification);
            }
            return StatusCode(response.StatusCode, response);
        }

        #endregion

        #region =================================================================== Project InfraStructure Get APIs ===================================================================

        [HttpGet("infra-details/{projectId}")]
        public async Task<IActionResult> GetInfraDetails(Guid projectId)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("Get Project Infrastructure by ProjectId called with invalid model state \n Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetInfraDetailsAsync(projectId, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);

        }

        [HttpGet("tasks/{workAreaId}")]
        public async Task<IActionResult> GetWorkItems(Guid workAreaId)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("Get Work Items by WorkAreaId called with invalid model state \n Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.GetWorkItemsAsync(workAreaId, tenantId, loggedInEmployee);
            return StatusCode(response.StatusCode, response);
        }

        #endregion

        #region =================================================================== Project Infrastructre Manage APIs ===================================================================

        [HttpPost("task")]
        public async Task<IActionResult> CreateProjectTask([FromBody] List<WorkItemDto> workItemDtos)
        {
            // --- Step 1: Input Validation ---
            if (!ModelState.IsValid)
            {
                var errors = ModelState.Values.SelectMany(v => v.Errors).Select(e => e.ErrorMessage).ToList();
                _logger.LogWarning("project Alocation called with invalid model state for list of projects. Errors: {Errors}", string.Join(", ", errors));
                return BadRequest(ApiResponse<object>.ErrorResponse("Invalid request data provided.", errors, 400));
            }

            // --- Step 2: Prepare data without I/O ---
            Employee loggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            var response = await _projectServices.CreateProjectTaskAsync(workItemDtos, tenantId, loggedInEmployee);
            if (response.Success)
            {
                List<Guid> workAreaIds = response.Data.Select(pa => pa.WorkItem?.WorkAreaId ?? Guid.Empty).ToList();
                string message = response.Message;

                var notification = new { LoggedInUserId = loggedInEmployee.Id, Keyword = "WorkItem", WorkAreaIds = workAreaIds, Message = message };
                await _signalR.SendNotificationAsync(notification);
            }
            return StatusCode(response.StatusCode, response);

        }

        [HttpDelete("task/{id}")]
        public async Task<IActionResult> DeleteProjectTask(Guid id)
        {
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();
            List<Guid> workAreaIds = new List<Guid>();
            WorkItem? task = await _context.WorkItems.AsNoTracking().Include(t => t.WorkArea).FirstOrDefaultAsync(t => t.Id == id && t.TenantId == tenantId);
            if (task != null)
            {
                if (task.CompletedWork == 0)
                {
                    var assignedTask = await _context.TaskAllocations.Where(t => t.WorkItemId == id).ToListAsync();
                    if (assignedTask.Count == 0)
                    {
                        _context.WorkItems.Remove(task);
                        await _context.SaveChangesAsync();
                        _logger.LogInfo("Task with ID {WorkItemId} has been successfully deleted.", task.Id);

                        var floorId = task.WorkArea?.FloorId;
                        var floor = await _context.Floor.Include(f => f.Building).FirstOrDefaultAsync(f => f.Id == floorId);


                        workAreaIds.Add(task.WorkAreaId);
                        var projectId = floor?.Building?.ProjectId;

                        var notification = new { LoggedInUserId = LoggedInEmployee.Id, Keyword = "WorkItem", WorkAreaIds = workAreaIds, Message = $"Task Deleted in Building: {floor?.Building?.Name}, on Floor: {floor?.FloorName}, in Area: {task.WorkArea?.AreaName} by {LoggedInEmployee.FirstName} {LoggedInEmployee.LastName}" };
                        await _signalR.SendNotificationAsync(notification);
                        await _cache.DeleteWorkItemByIdAsync(task.Id);
                        if (projectId != null)
                        {
                            await _cache.DeleteProjectByIdAsync(projectId.Value);
                        }
                    }
                    else
                    {
                        _logger.LogWarning("Task with ID {WorkItemId} is currently assigned and cannot be deleted.", task.Id);
                        return BadRequest(ApiResponse<object>.ErrorResponse("Task is currently assigned and cannot be deleted.", "Task is currently assigned and cannot be deleted.", 400));
                    }
                }
                else
                {
                    double percentage = (task.CompletedWork / task.PlannedWork) * 100;
                    percentage = Math.Round(percentage, 2);
                    _logger.LogWarning("Task with ID {WorkItemId} is {CompletionPercentage}% complete and cannot be deleted", task.Id, percentage);
                    return BadRequest(ApiResponse<object>.ErrorResponse(System.String.Format("Task is {0}% complete and cannot be deleted", percentage), System.String.Format("Task is {0}% complete and cannot be deleted", percentage), 400));

                }
            }
            else
            {
                _logger.LogWarning("Task with ID {WorkItemId} not found ID database", id);
            }
            return Ok(ApiResponse<object>.SuccessResponse(new { }, "Task deleted successfully", 200));
        }

        [HttpPost("manage-infra")]
        public async Task<IActionResult> ManageProjectInfra(List<InfraDot> infraDots)
        {
            var LoggedInEmployee = await _userHelper.GetCurrentEmployeeAsync();

            var responseData = new InfraVM { };
            string responseMessage = "";
            string message = "";
            List<Guid> projectIds = new List<Guid>();
            if (infraDots != null)
            {
                foreach (var item in infraDots)
                {
                    if (item.Building != null)
                    {

                        Building building = item.Building.ToBuildingFromBuildingDto(tenantId);
                        building.TenantId = tenantId;

                        if (item.Building.Id == null)
                        {
                            //create
                            _context.Buildings.Add(building);
                            await _context.SaveChangesAsync();
                            responseData.building = building;
                            responseMessage = "Buliding Added Successfully";
                            message = "Building Added";
                            await _cache.AddBuildngInfra(building.ProjectId, building);
                        }
                        else
                        {
                            //update
                            _context.Buildings.Update(building);
                            await _context.SaveChangesAsync();
                            responseData.building = building;
                            responseMessage = "Buliding Updated Successfully";
                            message = "Building Updated";
                            await _cache.UpdateBuildngInfra(building.ProjectId, building);
                        }
                        projectIds.Add(building.ProjectId);
                    }
                    if (item.Floor != null)
                    {
                        Floor floor = item.Floor.ToFloorFromFloorDto(tenantId);
                        floor.TenantId = tenantId;
                        bool isCreated = false;

                        if (item.Floor.Id == null)
                        {
                            //create
                            _context.Floor.Add(floor);
                            await _context.SaveChangesAsync();
                            responseData.floor = floor;
                            responseMessage = "Floor Added Successfully";
                            message = "Floor Added";
                            isCreated = true;
                        }
                        else
                        {
                            //update
                            _context.Floor.Update(floor);
                            await _context.SaveChangesAsync();
                            responseData.floor = floor;
                            responseMessage = "Floor Updated Successfully";
                            message = "Floor Updated";
                        }
                        Building? building = await _context.Buildings.FirstOrDefaultAsync(b => b.Id == floor.BuildingId);
                        var projectId = building?.ProjectId ?? Guid.Empty;
                        projectIds.Add(projectId);
                        message = $"{message} in Building: {building?.Name}";
                        if (isCreated)
                        {
                            await _cache.AddBuildngInfra(projectId, floor: floor);
                        }
                        else
                        {
                            await _cache.UpdateBuildngInfra(projectId, floor: floor);
                        }
                    }
                    if (item.WorkArea != null)
                    {
                        WorkArea workArea = item.WorkArea.ToWorkAreaFromWorkAreaDto(tenantId);
                        workArea.TenantId = tenantId;
                        bool isCreated = false;

                        if (item.WorkArea.Id == null)
                        {
                            //create
                            _context.WorkAreas.Add(workArea);
                            await _context.SaveChangesAsync();
                            responseData.workArea = workArea;
                            responseMessage = "Work Area Added Successfully";
                            message = "Work Area Added";
                            isCreated = true;
                        }
                        else
                        {
                            //update
                            _context.WorkAreas.Update(workArea);
                            await _context.SaveChangesAsync();
                            responseData.workArea = workArea;
                            responseMessage = "Work Area Updated Successfully";
                            message = "Work Area Updated";
                        }
                        Floor? floor = await _context.Floor.Include(f => f.Building).FirstOrDefaultAsync(f => f.Id == workArea.FloorId);
                        var projectId = floor?.Building?.ProjectId ?? Guid.Empty;
                        projectIds.Add(projectId);
                        message = $"{message} in Building: {floor?.Building?.Name}, on Floor: {floor?.FloorName}";
                        if (isCreated)
                        {
                            await _cache.AddBuildngInfra(projectId, workArea: workArea, buildingId: floor?.BuildingId);
                        }
                        else
                        {
                            await _cache.UpdateBuildngInfra(projectId, workArea: workArea, buildingId: floor?.BuildingId);
                        }
                    }
                }
                message = $"{message} by {LoggedInEmployee.FirstName} {LoggedInEmployee.LastName}";
                var notification = new { LoggedInUserId = LoggedInEmployee.Id, Keyword = "Infra", ProjectIds = projectIds, Message = message };

                await _signalR.SendNotificationAsync(notification);
                return Ok(ApiResponse<object>.SuccessResponse(responseData, responseMessage, 200));
            }
            return BadRequest(ApiResponse<object>.ErrorResponse("Invalid details.", "Infra Details are not valid.", 400));

        }

        #endregion

    }
}