<?php

namespace App\Services;

use App\Models\User;

/**
 * Profile Completion Service
 * 
 * Handles user profile completion calculations and analytics.
 * 
 * @author David Valera Melendez <david@valera-melendez.de>
 * @since February  2025
 */
class ProfileCompletionService
{
    /**
     * Required fields for profile completion
     */
    private const REQUIRED_FIELDS = [
        'first_name' => 10,
        'last_name' => 10,
        'email' => 15,
        'phone' => 10,
        'bio' => 20,
        'website' => 10,
        'linkedin' => 15,
        'github' => 10,
    ];

    /**
     * Calculate profile completion percentage
     */
    public function calculateCompletion(User $user): int
    {
        $totalWeight = array_sum(self::REQUIRED_FIELDS);
        $completedWeight = 0;

        foreach (self::REQUIRED_FIELDS as $field => $weight) {
            if (!empty($user->$field)) {
                $completedWeight += $weight;
            }
        }

        return (int) (($completedWeight / $totalWeight) * 100);
    }

    /**
     * Get missing profile fields
     */
    public function getMissingFields(User $user): array
    {
        $missing = [];

        foreach (self::REQUIRED_FIELDS as $field => $weight) {
            if (empty($user->$field)) {
                $missing[] = [
                    'field' => $field,
                    'label' => $this->getFieldLabel($field),
                    'weight' => $weight,
                ];
            }
        }

        return $missing;
    }

    /**
     * Get user-friendly field labels
     */
    private function getFieldLabel(string $field): string
    {
        $labels = [
            'first_name' => 'First Name',
            'last_name' => 'Last Name',
            'email' => 'Email Address',
            'phone' => 'Phone Number',
            'bio' => 'Professional Bio',
            'website' => 'Website',
            'linkedin' => 'LinkedIn Profile',
            'github' => 'GitHub Profile',
        ];

        return $labels[$field] ?? ucfirst(str_replace('_', ' ', $field));
    }

    /**
     * Check if profile is considered complete
     */
    public function isProfileComplete(User $user): bool
    {
        return $this->calculateCompletion($user) >= 80;
    }

    /**
     * Get profile completion statistics
     */
    public function getCompletionStats(User $user): array
    {
        $completion = $this->calculateCompletion($user);
        $missingFields = $this->getMissingFields($user);

        return [
            'completion_percentage' => $completion,
            'is_complete' => $this->isProfileComplete($user),
            'missing_fields' => $missingFields,
            'missing_count' => count($missingFields),
            'status' => $this->getCompletionStatus($completion),
        ];
    }

    /**
     * Get completion status message
     */
    private function getCompletionStatus(int $completion): string
    {
        if ($completion >= 90) {
            return 'excellent';
        } elseif ($completion >= 70) {
            return 'good';
        } elseif ($completion >= 50) {
            return 'fair';
        } else {
            return 'incomplete';
        }
    }
}