<?php

namespace App\Services;

use App\Models\Project;
use App\Models\Task;
use App\Models\Meeting;
use App\Models\ActivityLog;
use App\Models\Sprint;
use Carbon\Carbon;

class DashboardService
{
    public function getSummary($user = null)
    {
        $activeProjects = Project::where('status', '!=', 'done')->where('is_archived', false)->count();
        $completedProjects = Project::where('status', 'done')->count();
        $today = Carbon::today();
        $delayedProjects = Project::whereDate('end_date', '<', $today)->where('status', '!=', 'done')->where('is_archived', false)->count();

        $openTasks = Task::whereNotIn('status', ['done', 'canceled'])->count();
        $completedTasks = Task::where('status', 'done')->count();
        $delayedTasks = Task::whereDate('due_date', '<', $today)->where('status', '!=', 'done')->count();

        $teamPerformance = [];
        $workload = [];

        $riskyProjects = Project::whereIn('risk_level', ['high', 'critical'])->where('is_archived', false)->limit(5)->get();

        $upcomingDeadlines = Task::with('project')
            ->whereDate('due_date', '>=', $today)
            ->whereDate('due_date', '<=', $today->copy()->addDays(7))
            ->where('status', '!=', 'done')
            ->orderBy('due_date')
            ->limit(10)
            ->get()
            ->map(fn($t) => [
                'id' => $t->id,
                'title' => $t->title,
                'project' => $t->project?->title,
                'due_date' => $t->due_date?->format('Y-m-d'),
                'days_left' => $today->diffInDays($t->due_date, false),
            ]);

        $recentActivities = ActivityLog::with('user')
            ->orderBy('created_at', 'desc')
            ->limit(10)
            ->get()
            ->map(fn($log) => [
                'id' => $log->id,
                'description' => $log->description,
                'user' => $log->user?->name ?? '?',
                'created_at' => $log->created_at?->toDateTimeString(),
                'time_ago' => $log->created_at?->diffForHumans(),
            ]);

        $myTasks = collect();
        if ($user) {
            $myTasks = Task::where('assignee_id', $user->id)
                ->where('status', '!=', 'done')
                ->orderBy('due_date')
                ->limit(10)
                ->get();
        }

        $activeSprint = null;
        if ($user) {
            $sprint = Sprint::with(['project', 'tasks.assignee'])
                ->where('status', 'active')
                ->whereHas('members', fn($query) => $query->where('users.id', $user->id))
                ->orderBy('end_date')
                ->first();

            if ($sprint) {
                $totalTasks = $sprint->tasks->count();
                $completedTasks = $sprint->tasks->where('status', 'done')->count();
                $activeSprint = [
                    'id' => $sprint->id,
                    'title' => $sprint->title,
                    'project' => $sprint->project?->title,
                    'end_date' => $sprint->end_date?->format('Y-m-d'),
                    'remaining_days' => max(Carbon::today()->diffInDays($sprint->end_date, false), 0),
                    'progress' => $totalTasks > 0 ? round(($completedTasks / $totalTasks) * 100, 2) : 0,
                    'my_tasks' => $sprint->tasks
                        ->where('assignee_id', $user->id)
                        ->values()
                        ->map(fn($task) => [
                            'id' => $task->id,
                            'title' => $task->title,
                            'status' => $task->status,
                        ]),
                ];
            }
        }

        $todayMeetings = Meeting::whereDate('date', Carbon::today())->count();
        $teamMembers = \App\Models\User::count();

        $projectProgresses = Project::where('is_archived', false)
            ->select(['id', 'title', 'progress', 'status'])
            ->limit(10)
            ->get();

        return [
            'activeProjects' => $activeProjects,
            'completedProjects' => $completedProjects,
            'delayedProjects' => $delayedProjects,
            'openTasks' => $openTasks,
            'completedTasks' => $completedTasks,
            'delayedTasks' => $delayedTasks,
            'teamPerformance' => $teamPerformance,
            'workload' => $workload,
            'riskyProjects' => $riskyProjects,
            'upcomingDeadlines' => $upcomingDeadlines,
            'recentActivities' => $recentActivities,
            'myTasks' => $myTasks,
            'todayMeetings' => $todayMeetings,
            'teamMembers' => $teamMembers,
            'projectProgresses' => $projectProgresses,
            'activeSprint' => $activeSprint,
        ];
    }

    public function getChartData()
    {
        $months = collect();
        $taskCreationData = [];
        $taskCompletionData = [];

        for ($i = 5; $i >= 0; $i--) {
            $month = Carbon::now()->subMonths($i);
            $monthName = $month->format('Y-m');
            $months->push($monthName);

            $taskCreationData[] = Task::whereYear('created_at', $month->year)
                ->whereMonth('created_at', $month->month)
                ->count();

            $taskCompletionData[] = Task::where('status', 'done')
                ->whereYear('updated_at', $month->year)
                ->whereMonth('updated_at', $month->month)
                ->count();
        }

        $monthlyTasks = [];
        foreach ($months as $i => $month) {
            $monthlyTasks[] = [
                'month' => $month,
                'created' => $taskCreationData[$i],
                'completed' => $taskCompletionData[$i],
            ];
        }

        return [
            'labels' => $months->values(),
            'taskCreation' => $taskCreationData,
            'taskCompletion' => $taskCompletionData,
            'monthlyTasks' => $monthlyTasks,
            'monthly_tasks' => $monthlyTasks,
        ];
    }
}