<?php

namespace App\Http\Controllers;

use App\Helpers\CurrencyHelper;
use App\Helpers\CalendarHelper;
use App\Helpers\NumberHelper;
use App\Models\Project;
use App\Models\Task;
use App\Models\Employee;
use App\Models\Expense;
use App\Models\AuditLog;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\DB;

class DashboardController extends Controller
{
    /**
     * Display the dashboard with KPIs, recent activities, and project progress.
     * All data is tenant-scoped via global scope.
     */
    public function index()
    {
        $user = Auth::user();
        $tenantId = $this->getTenantId();
        $baseCurrency = CurrencyHelper::getBaseCurrency();
        $currencyCode = $baseCurrency?->code ?? config('projectra.defaults.currency', 'IRR');

        // --- KPIs ---
        $activeProjectsCount = Project::whereIn('status', ['planning', 'active'])->count();
        $totalBudget = Project::whereIn('status', ['planning', 'active'])
            ->sum('budget');
        $pendingTasksCount = Task::where('status', 'pending')->count();
         $activeEmployeesCount = Employee::where('status', 'active')->count();

        // Budget in base currency
        $totalBudgetFormatted = CurrencyHelper::formatWithSymbol((float) $totalBudget, $currencyCode);

        // --- Trends (compare with previous month) ---
        $lastMonthStart = now()->subMonth()->startOfMonth();
        $lastMonthEnd = now()->subMonth()->endOfMonth();

        $lastMonthProjects = Project::whereBetween('created_at', [$lastMonthStart, $lastMonthEnd])->count();
        $thisMonthProjects = Project::whereBetween('created_at', [now()->startOfMonth(), now()->endOfMonth()])->count();
        $projectTrend = $lastMonthProjects > 0
            ? round((($thisMonthProjects - $lastMonthProjects) / $lastMonthProjects) * 100, 1)
            : ($thisMonthProjects > 0 ? 100 : 0);

        $lastMonthTasks = Task::whereBetween('created_at', [$lastMonthStart, $lastMonthEnd])->count();
        $thisMonthTasks = Task::whereBetween('created_at', [now()->startOfMonth(), now()->endOfMonth()])->count();
        $taskTrend = $lastMonthTasks > 0
            ? round((($thisMonthTasks - $lastMonthTasks) / $lastMonthTasks) * 100, 1)
            : ($thisMonthTasks > 0 ? 100 : 0);

        $lastMonthExpenses = Expense::whereBetween('expense_date', [$lastMonthStart, $lastMonthEnd])
            ->where('status', 'approved')->sum('amount');
        $thisMonthExpenses = Expense::whereBetween('expense_date', [now()->startOfMonth(), now()->endOfMonth()])
            ->where('status', 'approved')->sum('amount');
        $expenseTrend = $lastMonthExpenses > 0
            ? round((($thisMonthExpenses - $lastMonthExpenses) / $lastMonthExpenses) * 100, 1)
            : ($thisMonthExpenses > 0 ? 100 : 0);

        $lastMonthEmployees = Employee::whereBetween('hire_date', [$lastMonthStart, $lastMonthEnd])->count();
        $thisMonthEmployees = Employee::whereBetween('hire_date', [now()->startOfMonth(), now()->endOfMonth()])->count();
        $employeeTrend = $lastMonthEmployees > 0
            ? round((($thisMonthEmployees - $lastMonthEmployees) / $lastMonthEmployees) * 100, 1)
            : ($thisMonthEmployees > 0 ? 100 : 0);

        // --- Project Progress ---
        $projectsInProgress = Project::whereIn('status', ['active', 'planning'])
            ->with(['manager', 'tasks'])
            ->orderBy('progress', 'desc')
            ->limit(5)
            ->get();

        // --- Recent Activities ---
        $recentActivities = AuditLog::where('tenant_id', $tenantId)
            ->with('user')
            ->orderBy('created_at', 'desc')
            ->limit(8)
            ->get();

        // --- Tasks by status for current user ---
        $myTasks = Task::where('assignee_id', $user->id)
            ->whereNotIn('status', ['done', 'cancelled'])
            ->with('project')
            ->orderBy('due_date', 'asc')
            ->limit(5)
            ->get();

        // --- Calendar & i18n info ---
        $currentCalendar = session('calendar', config('projectra.default_calendar', 'jalali'));
        $currentLocale = app()->getLocale();
        $todayDisplay = CalendarHelper::getCurrentDate($currentCalendar);
        if ($currentLocale === 'fa') {
            $todayDisplay = persian_num($todayDisplay);
        }

        return view('dashboard.index', compact(
            'activeProjectsCount',
            'totalBudget',
            'totalBudgetFormatted',
            'pendingTasksCount',
            'activeEmployeesCount',
            'projectTrend',
            'taskTrend',
            'expenseTrend',
            'employeeTrend',
            'projectsInProgress',
            'recentActivities',
            'myTasks',
            'currentCalendar',
            'currentLocale',
            'todayDisplay',
            'currencyCode'
        ));
    }
}