<?php

namespace App\Http\Controllers;

use App\Models\Announcement;
use App\Models\AnnouncementView;
use App\Models\Branch;
use App\Models\Department;
use App\Models\User;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Facades\Validator;
use Inertia\Inertia;

class AnnouncementController extends Controller
{
    /**
     * Display a listing of the resource.
     */
    public function index(Request $request)
    {
        if (Auth::user()->can('manage-announcements')) {
            $query = Announcement::with(['departments', 'branches'])->where(function ($q) {
                if (Auth::user()->can('manage-any-announcements')) {
                    $q->whereIn('created_by',  getCompanyAndUsersId());
                } elseif (Auth::user()->can('manage-own-announcements')) {
                    $q->where('created_by', Auth::id());
                } else {
                    $q->whereRaw('1 = 0');
                }
            });

            // Handle search
            if ($request->has('search') && !empty($request->search)) {
                $query->where(function ($q) use ($request) {
                    $q->where('title', 'like', '%' . $request->search . '%')
                        ->orWhere('description', 'like', '%' . $request->search . '%')
                        ->orWhere('content', 'like', '%' . $request->search . '%');
                });
            }

            // Handle category filter
            if ($request->has('category') && !empty($request->category)) {
                $query->where('category', $request->category);
            }

            // Handle department filter
            if ($request->has('department_id') && !empty($request->department_id)) {
                $query->where(function ($q) use ($request) {
                    $q->where('is_company_wide', true)
                        ->orWhereHas('departments', function ($q) use ($request) {
                            $q->where('departments.id', $request->department_id);
                        });
                });
            }

            // Handle branch filter
            if ($request->has('branch_id') && !empty($request->branch_id)) {
                $query->where(function ($q) use ($request) {
                    $q->where('is_company_wide', true)
                        ->orWhereHas('branches', function ($q) use ($request) {
                            $q->where('branches.id', $request->branch_id);
                        });
                });
            }

            // Handle status filter
            if ($request->has('status') && !empty($request->status)) {
                $today = now()->format('Y-m-d');

                if ($request->status === 'active') {
                    $query->where('start_date', '<=', $today)
                        ->where(function ($q) use ($today) {
                            $q->whereNull('end_date')
                                ->orWhere('end_date', '>=', $today);
                        });
                } elseif ($request->status === 'upcoming') {
                    $query->where('start_date', '>', $today);
                } elseif ($request->status === 'expired') {
                    $query->whereNotNull('end_date')
                        ->where('end_date', '<', $today);
                }
            }

            // Handle priority filter
            if ($request->has('priority') && !empty($request->priority)) {
                if ($request->priority === 'high') {
                    $query->where('is_high_priority', true);
                } elseif ($request->priority === 'normal') {
                    $query->where('is_high_priority', false);
                }
            }

            // Handle featured filter
            if ($request->has('featured') && $request->featured === 'true') {
                $query->where('is_featured', true);
            }

            // Handle date range filter
            if ($request->has('date_from') && !empty($request->date_from)) {
                $query->where(function ($q) use ($request) {
                    $q->where('start_date', '>=', $request->date_from)
                        ->orWhere('end_date', '>=', $request->date_from);
                });
            }
            if ($request->has('date_to') && !empty($request->date_to)) {
                $query->where(function ($q) use ($request) {
                    $q->where('start_date', '<=', $request->date_to)
                        ->orWhere('end_date', '<=', $request->date_to);
                });
            }

            // Handle sorting
            $allowedSortFields = ['id', 'title', 'category', 'start_date', 'end_date', 'is_featured', 'is_high_priority', 'created_at'];
            if ($request->has('sort_field') && !empty($request->sort_field)) {
                $sortField = $request->sort_field === 'date_range' ? 'start_date' : $request->sort_field;
                if (in_array($sortField, $allowedSortFields)) {
                    $sortDirection = in_array($request->sort_direction, ['asc', 'desc']) ? $request->sort_direction : 'asc';
                    $query->orderBy($sortField, $sortDirection);
                } else {
                    $query->orderBy('created_at', 'desc');
                }
            } else {
                $query->orderBy('created_at', 'desc');
            }

            $announcements = $query->paginate($request->per_page ?? 10);

            // Get departments for filter dropdown
            $departments = Department::whereIn('created_by', getCompanyAndUsersId())
                ->select('id', 'name')
                ->get();

            // Get branches for filter dropdown
            $branches = Branch::whereIn('created_by', getCompanyAndUsersId())
                ->select('id', 'name')
                ->get();

            // Get categories for filter dropdown
            $categories = Announcement::whereIn('created_by', getCompanyAndUsersId())
                ->select('category')
                ->distinct()
                ->pluck('category')
                ->toArray();

            return Inertia::render('hr/announcements/index', [
                'announcements' => $announcements,
                'departments' => $departments,
                'branches' => $branches,
                'categories' => $categories,
                'filters' => $request->all(['search', 'category', 'department_id', 'branch_id', 'status', 'priority', 'featured', 'date_from', 'date_to', 'sort_field', 'sort_direction', 'per_page']),
            ]);
        } else {
            return redirect()->back()->with('error', __('Permission Denied.'));
        }
    }

    /**
     * Display the dashboard view.
     */
    public function dashboard(Request $request)
    {
        $today = now()->format('Y-m-d');

        // Get all announcements (active, expired, upcoming)
        $allAnnouncements = Announcement::with(['departments', 'branches'])
            ->whereIn('created_by', getCompanyAndUsersId())
            ->orderBy('is_high_priority', 'desc')
            ->orderBy('is_featured', 'desc')
            ->orderBy('created_at', 'desc')
            ->get();

        // Get featured announcements (from all announcements)
        $featuredAnnouncements = Announcement::with(['departments', 'branches'])
            ->whereIn('created_by', getCompanyAndUsersId())
            ->where('is_featured', true)
            ->orderBy('created_at', 'desc')
            ->get();

        // Get high priority announcements (from all announcements)
        $highPriorityAnnouncements = Announcement::with(['departments', 'branches'])
            ->whereIn('created_by', getCompanyAndUsersId())
            ->where('is_high_priority', true)
            ->orderBy('created_at', 'desc')
            ->get();

        // Get upcoming announcements
        $upcomingAnnouncements = Announcement::with(['departments', 'branches'])
            ->whereIn('created_by', getCompanyAndUsersId())
            ->where('start_date', '>', $today)
            ->orderBy('start_date', 'asc')
            ->take(5)
            ->get();

        // Get categories for filter
        $categories = Announcement::whereIn('created_by', getCompanyAndUsersId())
            ->select('category')
            ->distinct()
            ->pluck('category')
            ->toArray();

        // Get departments for filter
        $departments = Department::whereIn('created_by', getCompanyAndUsersId())
            ->select('id', 'name')
            ->get();

        // Get branches for filter
        $branches = Branch::whereIn('created_by', getCompanyAndUsersId())
            ->select('id', 'name')
            ->get();

        // Get employee for marking announcements as read
        $employee = null;
        if (Auth::user()->type !== 'company' && Auth::user()->type !== 'superadmin') {
            $employee = User::where('id', Auth::id())->first();
        }

        return Inertia::render('hr/announcements/dashboard', [
            'allAnnouncements' => $allAnnouncements,
            'featuredAnnouncements' => $featuredAnnouncements,
            'highPriorityAnnouncements' => $highPriorityAnnouncements,
            'upcomingAnnouncements' => $upcomingAnnouncements,
            'categories' => $categories,
            'departments' => $departments,
            'branches' => $branches,
            'employee' => $employee,
            'filters' => $request->all(['category', 'department_id', 'branch_id']),
        ]);
    }

    /**
     * Store a newly created resource in storage.
     */
    public function store(Request $request)
    {
        $validator = Validator::make($request->all(), [
            'title' => 'required|string|max:255',
            'category' => 'required|string|max:255',
            'description' => 'nullable|string',
            'content' => 'required|string',
            'start_date' => 'required|date',
            'end_date' => 'nullable|date|after_or_equal:start_date',
            'attachments' => 'nullable|string',
            'is_featured' => 'nullable|boolean',
            'is_high_priority' => 'nullable|boolean',
            'is_company_wide' => 'nullable|boolean',
            'department_ids' => 'nullable|string|required_if:is_company_wide,false',
            'branch_ids' => 'nullable|string|required_if:is_company_wide,false',
        ]);

        if ($validator->fails()) {
            return redirect()->back()->withErrors($validator)->withInput();
        }

        // Check if departments and branches belong to current company
        if (
            !$request->is_company_wide &&
            (empty($request->department_ids) && empty($request->branch_ids))
        ) {
            return redirect()->back()->with('error', 'You must select at least one department or branch if the announcement is not company-wide');
        }

        if (!empty($request->department_ids)) {
            $validDepartment = Department::where('created_by', createdBy())
                ->where('id', $request->department_ids)
                ->exists();

            if (!$validDepartment) {
                return redirect()->back()->with('error', 'Invalid department selection');
            }
        }

        if (!empty($request->branch_ids)) {
            $validBranch = Branch::where('created_by', createdBy())
                ->where('id', $request->branch_ids)
                ->exists();

            if (!$validBranch) {
                return redirect()->back()->with('error', 'Invalid branch selection');
            }
        }

        $announcementData = [
            'title' => $request->title,
            'category' => $request->category,
            'description' => $request->description,
            'content' => $request->content,
            'start_date' => $request->start_date,
            'end_date' => $request->end_date,
            'is_featured' => $request->is_featured ?? false,
            'is_high_priority' => $request->is_high_priority ?? false,
            'is_company_wide' => $request->is_company_wide ?? true,
            'created_by' => creatorId(),
        ];

        // Handle attachment from media library
        if ($request->has('attachments')) {
            $announcementData['attachments'] = $request->attachments;
        }

        $announcement = Announcement::create($announcementData);

        // Attach departments and branches if not company-wide
        if (!$request->is_company_wide) {
            if (!empty($request->department_ids)) {
                $announcement->departments()->attach([$request->department_ids]);
            }

            if (!empty($request->branch_ids)) {
                $announcement->branches()->attach([$request->branch_ids]);
            }
        }

        return redirect()->back()->with('success', __('Announcement created successfully'));
    }

    /**
     * Display the specified resource.
     */
    public function show(Announcement $announcement)
    {
        // Check if announcement belongs to current company
        if (!in_array($announcement->created_by, getCompanyAndUsersId())) {
            return redirect()->back()->with('error', __('You do not have permission to view this announcement'));
        }

        // Load relationships
        $announcement->load(['departments', 'branches']);

        // Get view statistics
        $viewCount = $announcement->viewedBy()->count();
        $totalEmployees = User::where('type', 'employee')
            ->whereIn('created_by', getCompanyAndUsersId())
            ->count();
        $viewPercentage = $totalEmployees > 0 ? round(($viewCount / $totalEmployees) * 100) : 0;

        // Mark as viewed if current user is an employee
        if (Auth::user()->type !== 'company' && Auth::user()->type !== 'superadmin') {
            $employee = User::where('id', Auth::id())->first();

            if ($employee) {
                // Check if already viewed
                $existingView = AnnouncementView::where('announcement_id', $announcement->id)
                    ->where('employee_id', $employee->id)
                    ->first();

                if (!$existingView) {
                    // Mark as viewed
                    $announcement->viewedBy()->attach($employee->id, [
                        'viewed_at' => now()
                    ]);
                }
            }
        }

        return Inertia::render('hr/announcements/show', [
            'announcement' => $announcement,
            'viewCount' => $viewCount,
            'totalEmployees' => $totalEmployees,
            'viewPercentage' => $viewPercentage,
        ]);
    }

    /**
     * Update the specified resource in storage.
     */
    public function update(Request $request, Announcement $announcement)
    {
        // Check if announcement belongs to current company
        if (!in_array($announcement->created_by, getCompanyAndUsersId())) {
            return redirect()->back()->with('error', 'You do not have permission to update this announcement');
        }

        $validator = Validator::make($request->all(), [
            'title' => 'required|string|max:255',
            'category' => 'required|string|max:255',
            'description' => 'nullable|string',
            'content' => 'required|string',
            'start_date' => 'required|date',
            'end_date' => 'nullable|date|after_or_equal:start_date',
            'attachments' => 'nullable|string',
            'is_featured' => 'nullable|boolean',
            'is_high_priority' => 'nullable|boolean',
            'is_company_wide' => 'nullable|boolean',
            'department_ids' => 'nullable|string|required_if:is_company_wide,false',
            'branch_ids' => 'nullable|string|required_if:is_company_wide,false',
        ]);

        if ($validator->fails()) {
            return redirect()->back()->withErrors($validator)->withInput();
        }

        // Check if departments and branches belong to current company
        if (
            !$request->is_company_wide &&
            (empty($request->department_ids) && empty($request->branch_ids))
        ) {
            return redirect()->back()->with('error', 'You must select at least one department or branch if the announcement is not company-wide');
        }

        if (!empty($request->department_ids)) {
            $departmentId = $request->department_ids;
            $validDepartment = Department::where('created_by', createdBy())
                ->where('id', $departmentId)
                ->exists();

            if (!$validDepartment) {
                return redirect()->back()->with('error', 'Invalid department selection');
            }
        }

        if (!empty($request->branch_ids)) {
            $branchId = $request->branch_ids;
            $validBranch = Branch::where('created_by', createdBy())
                ->where('id', $branchId)
                ->exists();

            if (!$validBranch) {
                return redirect()->back()->with('error', 'Invalid branch selection');
            }
        }

        $announcementData = [
            'title' => $request->title,
            'category' => $request->category,
            'description' => $request->description,
            'content' => $request->content,
            'start_date' => $request->start_date,
            'end_date' => $request->end_date,
            'is_featured' => $request->is_featured ?? false,
            'is_high_priority' => $request->is_high_priority ?? false,
            'is_company_wide' => $request->is_company_wide ?? true,
        ];

        // Handle attachment from media library
        if ($request->has('attachments')) {
            $announcementData['attachments'] = $request->attachments;
        }

        $announcement->update($announcementData);

        // Sync departments and branches
        if ($request->is_company_wide) {
            $announcement->departments()->detach();
            $announcement->branches()->detach();
        } else {
            if (!empty($request->department_ids)) {
                $announcement->departments()->sync([$request->department_ids]);
            } else {
                $announcement->departments()->detach();
            }

            if (!empty($request->branch_ids)) {
                $announcement->branches()->sync([$request->branch_ids]);
            } else {
                $announcement->branches()->detach();
            }
        }

        return redirect()->back()->with('success', __('Announcement updated successfully'));
    }

    /**
     * Remove the specified resource from storage.
     */
    public function destroy(Announcement $announcement)
    {
        // Check if announcement belongs to current company
        if (!in_array($announcement->created_by, getCompanyAndUsersId())) {
            return redirect()->back()->with('error', 'You do not have permission to delete this announcement');
        }

        // Detach all departments and branches
        $announcement->departments()->detach();
        $announcement->branches()->detach();

        // Delete all views
        $announcement->viewedBy()->detach();

        // Delete the announcement
        $announcement->delete();

        return redirect()->back()->with('success', __('Announcement deleted successfully'));
    }

    /**
     * Download attachment file.
     */
    public function downloadAttachment(Announcement $announcement)
    {
        // Check if announcement belongs to current company
        if (!in_array($announcement->created_by, getCompanyAndUsersId())) {
            return redirect()->back()->with('error', __('You do not have permission to access this attachment'));
        }

        if (!$announcement->attachments) {
            return redirect()->back()->with('error', __('Attachment file not found'));
        }

        $filePath = getStorageFilePath($announcement->attachments);

        if (!file_exists($filePath)) {
            return redirect()->back()->with('error', __('Attachment file not found'));
        }

        return response()->download($filePath);
    }

    /**
     * Mark announcement as read for current employee.
     */
    public function markAsRead(Request $request, Announcement $announcement)
    {
        $employee = User::where('id', Auth::id())->first();

        if (!$employee) {
            return response()->json(['error' => 'Employee not found'], 404);
        }

        // Check if already viewed
        $existingView = AnnouncementView::where('announcement_id', $announcement->id)
            ->where('employee_id', $employee->id)
            ->first();

        if (!$existingView) {
            // Mark as viewed
            $announcement->viewedBy()->attach($employee->id, [
                'viewed_at' => now()
            ]);
        }

        return response()->json(['success' => true]);
    }

    /**
     * Get announcement view statistics.
     */
    public function viewStatistics(Announcement $announcement)
    {
        // Check if announcement belongs to current company
        if (!in_array($announcement->created_by, getCompanyAndUsersId())) {
            return redirect()->back()->with('error', __('You do not have permission to view these statistics'));
        }

        // Load viewed by (employees)
        $views = $announcement->viewedBy()->get();

        // Get total employees
        $totalEmployees = User::where('type', 'employee')->whereIn('created_by', getCompanyAndUsersId())->count();

        // Get statistics only for announcement's target branch and department
        $departmentStats = [];
        $branchStats = [];

        if (!$announcement->is_company_wide) {
            // Get target branch and department
            $targetBranch = $announcement->branches->first();
            $targetDepartment = $announcement->departments->first();

            if ($targetBranch) {
                $branchEmployees = User::where('type', 'employee')->whereIn('created_by', getCompanyAndUsersId())->whereHas('employee', function ($q) use ($targetBranch) {
                    $q->where('branch_id', $targetBranch->id);
                })->count();
                $branchViews = $announcement->viewedBy()
                    ->whereHas('employee', function ($q) use ($targetBranch) {
                        $q->where('branch_id', $targetBranch->id);
                    })
                    ->count();

                $branchStats[] = [
                    'branch' => $targetBranch->name,
                    'total' => $branchEmployees,
                    'viewed' => $branchViews,
                    'percentage' => $branchEmployees > 0 ? round(($branchViews / $branchEmployees) * 100) : 0
                ];
            }

            if ($targetDepartment) {
                $departmentEmployees = User::where('type', 'employee')->whereIn('created_by', getCompanyAndUsersId())->whereHas('employee', function ($q) use ($targetDepartment) {
                    $q->where('department_id', $targetDepartment->id);
                })->count();

                $departmentViews = $announcement->viewedBy()
                    ->whereHas('employee', function ($q) use ($targetDepartment) {
                        $q->where('department_id', $targetDepartment->id);
                    })
                    ->count();

                $departmentStats[] = [
                    'branch_name' => $targetBranch ? $targetBranch->name : 'Unknown',
                    'departments' => [[
                        'department' => $targetDepartment->name,
                        'total' => $departmentEmployees,
                        'viewed' => $departmentViews,
                        'percentage' => $departmentEmployees > 0 ? round(($departmentViews / $departmentEmployees) * 100) : 0
                    ]]
                ];
            }
        }

        return Inertia::render('hr/announcements/statistics', [
            'announcement' => $announcement,
            'totalEmployees' => $totalEmployees,
            'viewedCount' => $views->count(),
            'viewPercentage' => $totalEmployees > 0 ? round(($views->count() / $totalEmployees) * 100) : 0,
            'departmentStats' => $departmentStats,
            'branchStats' => $branchStats,
        ]);
    }

    /**
     * Get departments based on selected branches.
     */
    public function getDepartments($branchIds)
    {
        $branchIdArray = explode(',', $branchIds);

        $departments = Department::whereIn('branch_id', $branchIdArray)
            ->whereIn('created_by', getCompanyAndUsersId())
            ->select('id', 'name')
            ->get()
            ->map(function ($dept) {
                return [
                    'value' => $dept->id,
                    'label' => $dept->name
                ];
            });
        return response()->json($departments);
    }
}