<?php

namespace App\Policies;

use App\Models\ClassProgressReport;
use App\Models\TeacherClass;
use App\Models\User;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;

class ClassProgressReportPolicy
{
    public function viewAny(User $user): bool
    {
        return $user !== null;
    }

    public function view(User $user, ClassProgressReport $report): bool
    {
        if ($this->isAdmin($user)) {
            return true;
        }

        return $this->isAuthor($user, $report)
            || $this->teachesSection($user, $report)
            || $this->parentHasEnrolledSection($user, $report);
    }

    public function create(User $user): bool
    {
        return $user !== null;
    }

    public function update(User $user, ClassProgressReport $report): bool
    {
        return $this->isAdmin($user) || $this->isAuthor($user, $report);
    }

    public function delete(User $user, ClassProgressReport $report): bool
    {
        return $this->isAdmin($user) || $this->isAuthor($user, $report);
    }

    private function isAuthor(User $user, ClassProgressReport $report): bool
    {
        return (int) $report->teacher_id === (int) $user->id;
    }

    /** Same relaxed section membership used by `ClassProgressQueryService::listReports`. */
    private function teachesSection(User $user, ClassProgressReport $report): bool
    {
        return in_array(
            (int) $report->class_section_id,
            TeacherClass::distinctAccessibleSectionIdsForTeacher((int) $user->id),
            true
        );
    }

    private function isAdmin(User $user): bool
    {
        $roles = $user->roles()
            ->pluck('roles.name')
            ->map(fn ($name) => strtolower((string) $name))
            ->toArray();

        foreach (['administrator', 'admin', 'principal', 'vice_principal', 'vice-principal'] as $role) {
            if (in_array($role, $roles, true)) {
                return true;
            }
        }

        return false;
    }

    private function parentHasEnrolledSection(User $user, ClassProgressReport $report): bool
    {
        if (! Schema::hasTable('enrollments')) {
            return false;
        }

        $parentId = (int) (request()?->attributes?->get('primary_parent_id') ?? 0);
        if ($parentId <= 0) {
            if (! $this->isParent($user)) {
                return false;
            }

            $parentId = (int) $user->id;
        }

        return DB::table('enrollments')
            ->where('parent_id', $parentId)
            ->where('class_section_id', (int) $report->class_section_id)
            ->where('is_withdrawn', 0)
            ->exists();
    }

    private function isParent(User $user): bool
    {
        return $user->roles()
            ->pluck('roles.name')
            ->map(fn ($name) => strtolower((string) $name))
            ->contains('parent');
    }
}